llvm-6502/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
Duncan Sands b0f1e1780c Add a new codegen pass that normalizes dwarf exception handling
code in preparation for code generation.  The main thing it does
is handle the case when eh.exception calls (and, in a future
patch, eh.selector calls) are far away from landing pads.  Right
now in practice you only find eh.exception calls close to landing
pads: either in a landing pad (the common case) or in a landing
pad successor, due to loop passes shifting them about.  However
future exception handling improvements will result in calls far
from landing pads:
(1) Inlining of rewinds.  Consider the following case:
In function @f:
...
  invoke @g to label %normal unwind label %unwinds
...
unwinds:
  %ex = call i8* @llvm.eh.exception()
...

In function @g:
...
  invoke @something to label %continue unwind label %handler
...
handler:
  %ex = call i8* @llvm.eh.exception()
... perform cleanups ...
  "rethrow exception"

Now inline @g into @f.  Currently this is turned into:
In function @f:
...
  invoke @something to label %continue unwind label %handler
...
handler:
  %ex = call i8* @llvm.eh.exception()
... perform cleanups ...
  invoke "rethrow exception" to label %normal unwind label %unwinds
unwinds:
  %ex = call i8* @llvm.eh.exception()
...

However we would like to simplify invoke of "rethrow exception" into
a branch to the %unwinds label.  Then %unwinds is no longer a landing
pad, and the eh.exception call there is then far away from any landing
pads.

(2) Using the unwind instruction for cleanups.
It would be nice to have codegen handle the following case:
  invoke @something to label %continue unwind label %run_cleanups
...
handler:
... perform cleanups ...
  unwind

This requires turning "unwind" into a library call, which
necessarily takes a pointer to the exception as an argument
(this patch also does this unwind lowering).  But that means
you are using eh.exception again far from a landing pad.

(3) Bugpoint simplifications.  When bugpoint is simplifying
exception handling code it often generates eh.exception calls
far from a landing pad, which then causes codegen to assert.
Bugpoint then latches on to this assertion and loses sight
of the original problem.

Note that it is currently rare for this pass to actually do
anything.  And in fact it normally shouldn't do anything at
all given the code coming out of llvm-gcc!  But it does fire
a few times in the testsuite.  As far as I can see this is
almost always due to the LoopStrengthReduce codegen pass
introducing pointless loop preheader blocks which are landing
pads and only contain a branch to another block.  This other
block contains an eh.exception call.  So probably by tweaking
LoopStrengthReduce a bit this can be avoided.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72276 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-22 20:36:31 +00:00

6053 lines
235 KiB
C++

//===-- SelectionDAGBuild.cpp - Selection-DAG building --------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This implements routines for translating from LLVM IR into SelectionDAG IR.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "isel"
#include "SelectionDAGBuild.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Constants.h"
#include "llvm/CallingConv.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/GlobalVariable.h"
#include "llvm/InlineAsm.h"
#include "llvm/Instructions.h"
#include "llvm/Intrinsics.h"
#include "llvm/IntrinsicInst.h"
#include "llvm/Module.h"
#include "llvm/CodeGen/FastISel.h"
#include "llvm/CodeGen/GCStrategy.h"
#include "llvm/CodeGen/GCMetadata.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/PseudoSourceValue.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/DwarfWriter.h"
#include "llvm/Analysis/DebugInfo.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetFrameInfo.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetIntrinsicInfo.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
using namespace llvm;
/// LimitFloatPrecision - Generate low-precision inline sequences for
/// some float libcalls (6, 8 or 12 bits).
static unsigned LimitFloatPrecision;
static cl::opt<unsigned, true>
LimitFPPrecision("limit-float-precision",
cl::desc("Generate low-precision inline sequences "
"for some float libcalls"),
cl::location(LimitFloatPrecision),
cl::init(0));
/// ComputeLinearIndex - Given an LLVM IR aggregate type and a sequence
/// of insertvalue or extractvalue indices that identify a member, return
/// the linearized index of the start of the member.
///
static unsigned ComputeLinearIndex(const TargetLowering &TLI, const Type *Ty,
const unsigned *Indices,
const unsigned *IndicesEnd,
unsigned CurIndex = 0) {
// Base case: We're done.
if (Indices && Indices == IndicesEnd)
return CurIndex;
// Given a struct type, recursively traverse the elements.
if (const StructType *STy = dyn_cast<StructType>(Ty)) {
for (StructType::element_iterator EB = STy->element_begin(),
EI = EB,
EE = STy->element_end();
EI != EE; ++EI) {
if (Indices && *Indices == unsigned(EI - EB))
return ComputeLinearIndex(TLI, *EI, Indices+1, IndicesEnd, CurIndex);
CurIndex = ComputeLinearIndex(TLI, *EI, 0, 0, CurIndex);
}
return CurIndex;
}
// Given an array type, recursively traverse the elements.
else if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
const Type *EltTy = ATy->getElementType();
for (unsigned i = 0, e = ATy->getNumElements(); i != e; ++i) {
if (Indices && *Indices == i)
return ComputeLinearIndex(TLI, EltTy, Indices+1, IndicesEnd, CurIndex);
CurIndex = ComputeLinearIndex(TLI, EltTy, 0, 0, CurIndex);
}
return CurIndex;
}
// We haven't found the type we're looking for, so keep searching.
return CurIndex + 1;
}
/// ComputeValueVTs - Given an LLVM IR type, compute a sequence of
/// MVTs that represent all the individual underlying
/// non-aggregate types that comprise it.
///
/// If Offsets is non-null, it points to a vector to be filled in
/// with the in-memory offsets of each of the individual values.
///
static void ComputeValueVTs(const TargetLowering &TLI, const Type *Ty,
SmallVectorImpl<MVT> &ValueVTs,
SmallVectorImpl<uint64_t> *Offsets = 0,
uint64_t StartingOffset = 0) {
// Given a struct type, recursively traverse the elements.
if (const StructType *STy = dyn_cast<StructType>(Ty)) {
const StructLayout *SL = TLI.getTargetData()->getStructLayout(STy);
for (StructType::element_iterator EB = STy->element_begin(),
EI = EB,
EE = STy->element_end();
EI != EE; ++EI)
ComputeValueVTs(TLI, *EI, ValueVTs, Offsets,
StartingOffset + SL->getElementOffset(EI - EB));
return;
}
// Given an array type, recursively traverse the elements.
if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
const Type *EltTy = ATy->getElementType();
uint64_t EltSize = TLI.getTargetData()->getTypeAllocSize(EltTy);
for (unsigned i = 0, e = ATy->getNumElements(); i != e; ++i)
ComputeValueVTs(TLI, EltTy, ValueVTs, Offsets,
StartingOffset + i * EltSize);
return;
}
// Interpret void as zero return values.
if (Ty == Type::VoidTy)
return;
// Base case: we can get an MVT for this LLVM IR type.
ValueVTs.push_back(TLI.getValueType(Ty));
if (Offsets)
Offsets->push_back(StartingOffset);
}
namespace llvm {
/// RegsForValue - This struct represents the registers (physical or virtual)
/// that a particular set of values is assigned, and the type information about
/// the value. The most common situation is to represent one value at a time,
/// but struct or array values are handled element-wise as multiple values.
/// The splitting of aggregates is performed recursively, so that we never
/// have aggregate-typed registers. The values at this point do not necessarily
/// have legal types, so each value may require one or more registers of some
/// legal type.
///
struct VISIBILITY_HIDDEN RegsForValue {
/// TLI - The TargetLowering object.
///
const TargetLowering *TLI;
/// ValueVTs - The value types of the values, which may not be legal, and
/// may need be promoted or synthesized from one or more registers.
///
SmallVector<MVT, 4> ValueVTs;
/// RegVTs - The value types of the registers. This is the same size as
/// ValueVTs and it records, for each value, what the type of the assigned
/// register or registers are. (Individual values are never synthesized
/// from more than one type of register.)
///
/// With virtual registers, the contents of RegVTs is redundant with TLI's
/// getRegisterType member function, however when with physical registers
/// it is necessary to have a separate record of the types.
///
SmallVector<MVT, 4> RegVTs;
/// Regs - This list holds the registers assigned to the values.
/// Each legal or promoted value requires one register, and each
/// expanded value requires multiple registers.
///
SmallVector<unsigned, 4> Regs;
RegsForValue() : TLI(0) {}
RegsForValue(const TargetLowering &tli,
const SmallVector<unsigned, 4> &regs,
MVT regvt, MVT valuevt)
: TLI(&tli), ValueVTs(1, valuevt), RegVTs(1, regvt), Regs(regs) {}
RegsForValue(const TargetLowering &tli,
const SmallVector<unsigned, 4> &regs,
const SmallVector<MVT, 4> &regvts,
const SmallVector<MVT, 4> &valuevts)
: TLI(&tli), ValueVTs(valuevts), RegVTs(regvts), Regs(regs) {}
RegsForValue(const TargetLowering &tli,
unsigned Reg, const Type *Ty) : TLI(&tli) {
ComputeValueVTs(tli, Ty, ValueVTs);
for (unsigned Value = 0, e = ValueVTs.size(); Value != e; ++Value) {
MVT ValueVT = ValueVTs[Value];
unsigned NumRegs = TLI->getNumRegisters(ValueVT);
MVT RegisterVT = TLI->getRegisterType(ValueVT);
for (unsigned i = 0; i != NumRegs; ++i)
Regs.push_back(Reg + i);
RegVTs.push_back(RegisterVT);
Reg += NumRegs;
}
}
/// append - Add the specified values to this one.
void append(const RegsForValue &RHS) {
TLI = RHS.TLI;
ValueVTs.append(RHS.ValueVTs.begin(), RHS.ValueVTs.end());
RegVTs.append(RHS.RegVTs.begin(), RHS.RegVTs.end());
Regs.append(RHS.Regs.begin(), RHS.Regs.end());
}
/// getCopyFromRegs - Emit a series of CopyFromReg nodes that copies from
/// this value and returns the result as a ValueVTs value. This uses
/// Chain/Flag as the input and updates them for the output Chain/Flag.
/// If the Flag pointer is NULL, no flag is used.
SDValue getCopyFromRegs(SelectionDAG &DAG, DebugLoc dl,
SDValue &Chain, SDValue *Flag) const;
/// getCopyToRegs - Emit a series of CopyToReg nodes that copies the
/// specified value into the registers specified by this object. This uses
/// Chain/Flag as the input and updates them for the output Chain/Flag.
/// If the Flag pointer is NULL, no flag is used.
void getCopyToRegs(SDValue Val, SelectionDAG &DAG, DebugLoc dl,
SDValue &Chain, SDValue *Flag) const;
/// AddInlineAsmOperands - Add this value to the specified inlineasm node
/// operand list. This adds the code marker, matching input operand index
/// (if applicable), and includes the number of values added into it.
void AddInlineAsmOperands(unsigned Code,
bool HasMatching, unsigned MatchingIdx,
SelectionDAG &DAG, std::vector<SDValue> &Ops) const;
};
}
/// isUsedOutsideOfDefiningBlock - Return true if this instruction is used by
/// PHI nodes or outside of the basic block that defines it, or used by a
/// switch or atomic instruction, which may expand to multiple basic blocks.
static bool isUsedOutsideOfDefiningBlock(Instruction *I) {
if (isa<PHINode>(I)) return true;
BasicBlock *BB = I->getParent();
for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI != E; ++UI)
if (cast<Instruction>(*UI)->getParent() != BB || isa<PHINode>(*UI))
return true;
return false;
}
/// isOnlyUsedInEntryBlock - If the specified argument is only used in the
/// entry block, return true. This includes arguments used by switches, since
/// the switch may expand into multiple basic blocks.
static bool isOnlyUsedInEntryBlock(Argument *A, bool EnableFastISel) {
// With FastISel active, we may be splitting blocks, so force creation
// of virtual registers for all non-dead arguments.
// Don't force virtual registers for byval arguments though, because
// fast-isel can't handle those in all cases.
if (EnableFastISel && !A->hasByValAttr())
return A->use_empty();
BasicBlock *Entry = A->getParent()->begin();
for (Value::use_iterator UI = A->use_begin(), E = A->use_end(); UI != E; ++UI)
if (cast<Instruction>(*UI)->getParent() != Entry || isa<SwitchInst>(*UI))
return false; // Use not in entry block.
return true;
}
FunctionLoweringInfo::FunctionLoweringInfo(TargetLowering &tli)
: TLI(tli) {
}
void FunctionLoweringInfo::set(Function &fn, MachineFunction &mf,
SelectionDAG &DAG,
bool EnableFastISel) {
Fn = &fn;
MF = &mf;
RegInfo = &MF->getRegInfo();
// Create a vreg for each argument register that is not dead and is used
// outside of the entry block for the function.
for (Function::arg_iterator AI = Fn->arg_begin(), E = Fn->arg_end();
AI != E; ++AI)
if (!isOnlyUsedInEntryBlock(AI, EnableFastISel))
InitializeRegForValue(AI);
// Initialize the mapping of values to registers. This is only set up for
// instruction values that are used outside of the block that defines
// them.
Function::iterator BB = Fn->begin(), EB = Fn->end();
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
if (AllocaInst *AI = dyn_cast<AllocaInst>(I))
if (ConstantInt *CUI = dyn_cast<ConstantInt>(AI->getArraySize())) {
const Type *Ty = AI->getAllocatedType();
uint64_t TySize = TLI.getTargetData()->getTypeAllocSize(Ty);
unsigned Align =
std::max((unsigned)TLI.getTargetData()->getPrefTypeAlignment(Ty),
AI->getAlignment());
TySize *= CUI->getZExtValue(); // Get total allocated size.
if (TySize == 0) TySize = 1; // Don't create zero-sized stack objects.
StaticAllocaMap[AI] =
MF->getFrameInfo()->CreateStackObject(TySize, Align);
}
for (; BB != EB; ++BB)
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
if (!I->use_empty() && isUsedOutsideOfDefiningBlock(I))
if (!isa<AllocaInst>(I) ||
!StaticAllocaMap.count(cast<AllocaInst>(I)))
InitializeRegForValue(I);
// Create an initial MachineBasicBlock for each LLVM BasicBlock in F. This
// also creates the initial PHI MachineInstrs, though none of the input
// operands are populated.
for (BB = Fn->begin(), EB = Fn->end(); BB != EB; ++BB) {
MachineBasicBlock *MBB = mf.CreateMachineBasicBlock(BB);
MBBMap[BB] = MBB;
MF->push_back(MBB);
// Create Machine PHI nodes for LLVM PHI nodes, lowering them as
// appropriate.
PHINode *PN;
DebugLoc DL;
for (BasicBlock::iterator
I = BB->begin(), E = BB->end(); I != E; ++I) {
if (CallInst *CI = dyn_cast<CallInst>(I)) {
if (Function *F = CI->getCalledFunction()) {
switch (F->getIntrinsicID()) {
default: break;
case Intrinsic::dbg_stoppoint: {
DbgStopPointInst *SPI = cast<DbgStopPointInst>(I);
if (DIDescriptor::ValidDebugInfo(SPI->getContext(),
CodeGenOpt::Default)) {
DICompileUnit CU(cast<GlobalVariable>(SPI->getContext()));
unsigned idx = MF->getOrCreateDebugLocID(CU.getGV(),
SPI->getLine(),
SPI->getColumn());
DL = DebugLoc::get(idx);
}
break;
}
case Intrinsic::dbg_func_start: {
DbgFuncStartInst *FSI = cast<DbgFuncStartInst>(I);
Value *SP = FSI->getSubprogram();
if (DIDescriptor::ValidDebugInfo(SP, CodeGenOpt::Default)) {
DISubprogram Subprogram(cast<GlobalVariable>(SP));
DICompileUnit CU(Subprogram.getCompileUnit());
unsigned Line = Subprogram.getLineNumber();
DL = DebugLoc::get(MF->getOrCreateDebugLocID(CU.getGV(),
Line, 0));
}
break;
}
}
}
}
PN = dyn_cast<PHINode>(I);
if (!PN || PN->use_empty()) continue;
unsigned PHIReg = ValueMap[PN];
assert(PHIReg && "PHI node does not have an assigned virtual register!");
SmallVector<MVT, 4> ValueVTs;
ComputeValueVTs(TLI, PN->getType(), ValueVTs);
for (unsigned vti = 0, vte = ValueVTs.size(); vti != vte; ++vti) {
MVT VT = ValueVTs[vti];
unsigned NumRegisters = TLI.getNumRegisters(VT);
const TargetInstrInfo *TII = MF->getTarget().getInstrInfo();
for (unsigned i = 0; i != NumRegisters; ++i)
BuildMI(MBB, DL, TII->get(TargetInstrInfo::PHI), PHIReg + i);
PHIReg += NumRegisters;
}
}
}
}
unsigned FunctionLoweringInfo::MakeReg(MVT VT) {
return RegInfo->createVirtualRegister(TLI.getRegClassFor(VT));
}
/// CreateRegForValue - Allocate the appropriate number of virtual registers of
/// the correctly promoted or expanded types. Assign these registers
/// consecutive vreg numbers and return the first assigned number.
///
/// In the case that the given value has struct or array type, this function
/// will assign registers for each member or element.
///
unsigned FunctionLoweringInfo::CreateRegForValue(const Value *V) {
SmallVector<MVT, 4> ValueVTs;
ComputeValueVTs(TLI, V->getType(), ValueVTs);
unsigned FirstReg = 0;
for (unsigned Value = 0, e = ValueVTs.size(); Value != e; ++Value) {
MVT ValueVT = ValueVTs[Value];
MVT RegisterVT = TLI.getRegisterType(ValueVT);
unsigned NumRegs = TLI.getNumRegisters(ValueVT);
for (unsigned i = 0; i != NumRegs; ++i) {
unsigned R = MakeReg(RegisterVT);
if (!FirstReg) FirstReg = R;
}
}
return FirstReg;
}
/// getCopyFromParts - Create a value that contains the specified legal parts
/// combined into the value they represent. If the parts combine to a type
/// larger then ValueVT then AssertOp can be used to specify whether the extra
/// bits are known to be zero (ISD::AssertZext) or sign extended from ValueVT
/// (ISD::AssertSext).
static SDValue getCopyFromParts(SelectionDAG &DAG, DebugLoc dl,
const SDValue *Parts,
unsigned NumParts, MVT PartVT, MVT ValueVT,
ISD::NodeType AssertOp = ISD::DELETED_NODE) {
assert(NumParts > 0 && "No parts to assemble!");
const TargetLowering &TLI = DAG.getTargetLoweringInfo();
SDValue Val = Parts[0];
if (NumParts > 1) {
// Assemble the value from multiple parts.
if (!ValueVT.isVector() && ValueVT.isInteger()) {
unsigned PartBits = PartVT.getSizeInBits();
unsigned ValueBits = ValueVT.getSizeInBits();
// Assemble the power of 2 part.
unsigned RoundParts = NumParts & (NumParts - 1) ?
1 << Log2_32(NumParts) : NumParts;
unsigned RoundBits = PartBits * RoundParts;
MVT RoundVT = RoundBits == ValueBits ?
ValueVT : MVT::getIntegerVT(RoundBits);
SDValue Lo, Hi;
MVT HalfVT = MVT::getIntegerVT(RoundBits/2);
if (RoundParts > 2) {
Lo = getCopyFromParts(DAG, dl, Parts, RoundParts/2, PartVT, HalfVT);
Hi = getCopyFromParts(DAG, dl, Parts+RoundParts/2, RoundParts/2,
PartVT, HalfVT);
} else {
Lo = DAG.getNode(ISD::BIT_CONVERT, dl, HalfVT, Parts[0]);
Hi = DAG.getNode(ISD::BIT_CONVERT, dl, HalfVT, Parts[1]);
}
if (TLI.isBigEndian())
std::swap(Lo, Hi);
Val = DAG.getNode(ISD::BUILD_PAIR, dl, RoundVT, Lo, Hi);
if (RoundParts < NumParts) {
// Assemble the trailing non-power-of-2 part.
unsigned OddParts = NumParts - RoundParts;
MVT OddVT = MVT::getIntegerVT(OddParts * PartBits);
Hi = getCopyFromParts(DAG, dl,
Parts+RoundParts, OddParts, PartVT, OddVT);
// Combine the round and odd parts.
Lo = Val;
if (TLI.isBigEndian())
std::swap(Lo, Hi);
MVT TotalVT = MVT::getIntegerVT(NumParts * PartBits);
Hi = DAG.getNode(ISD::ANY_EXTEND, dl, TotalVT, Hi);
Hi = DAG.getNode(ISD::SHL, dl, TotalVT, Hi,
DAG.getConstant(Lo.getValueType().getSizeInBits(),
TLI.getPointerTy()));
Lo = DAG.getNode(ISD::ZERO_EXTEND, dl, TotalVT, Lo);
Val = DAG.getNode(ISD::OR, dl, TotalVT, Lo, Hi);
}
} else if (ValueVT.isVector()) {
// Handle a multi-element vector.
MVT IntermediateVT, RegisterVT;
unsigned NumIntermediates;
unsigned NumRegs =
TLI.getVectorTypeBreakdown(ValueVT, IntermediateVT, NumIntermediates,
RegisterVT);
assert(NumRegs == NumParts && "Part count doesn't match vector breakdown!");
NumParts = NumRegs; // Silence a compiler warning.
assert(RegisterVT == PartVT && "Part type doesn't match vector breakdown!");
assert(RegisterVT == Parts[0].getValueType() &&
"Part type doesn't match part!");
// Assemble the parts into intermediate operands.
SmallVector<SDValue, 8> Ops(NumIntermediates);
if (NumIntermediates == NumParts) {
// If the register was not expanded, truncate or copy the value,
// as appropriate.
for (unsigned i = 0; i != NumParts; ++i)
Ops[i] = getCopyFromParts(DAG, dl, &Parts[i], 1,
PartVT, IntermediateVT);
} else if (NumParts > 0) {
// If the intermediate type was expanded, build the intermediate operands
// from the parts.
assert(NumParts % NumIntermediates == 0 &&
"Must expand into a divisible number of parts!");
unsigned Factor = NumParts / NumIntermediates;
for (unsigned i = 0; i != NumIntermediates; ++i)
Ops[i] = getCopyFromParts(DAG, dl, &Parts[i * Factor], Factor,
PartVT, IntermediateVT);
}
// Build a vector with BUILD_VECTOR or CONCAT_VECTORS from the intermediate
// operands.
Val = DAG.getNode(IntermediateVT.isVector() ?
ISD::CONCAT_VECTORS : ISD::BUILD_VECTOR, dl,
ValueVT, &Ops[0], NumIntermediates);
} else if (PartVT.isFloatingPoint()) {
// FP split into multiple FP parts (for ppcf128)
assert(ValueVT == MVT(MVT::ppcf128) && PartVT == MVT(MVT::f64) &&
"Unexpected split");
SDValue Lo, Hi;
Lo = DAG.getNode(ISD::BIT_CONVERT, dl, MVT(MVT::f64), Parts[0]);
Hi = DAG.getNode(ISD::BIT_CONVERT, dl, MVT(MVT::f64), Parts[1]);
if (TLI.isBigEndian())
std::swap(Lo, Hi);
Val = DAG.getNode(ISD::BUILD_PAIR, dl, ValueVT, Lo, Hi);
} else {
// FP split into integer parts (soft fp)
assert(ValueVT.isFloatingPoint() && PartVT.isInteger() &&
!PartVT.isVector() && "Unexpected split");
MVT IntVT = MVT::getIntegerVT(ValueVT.getSizeInBits());
Val = getCopyFromParts(DAG, dl, Parts, NumParts, PartVT, IntVT);
}
}
// There is now one part, held in Val. Correct it to match ValueVT.
PartVT = Val.getValueType();
if (PartVT == ValueVT)
return Val;
if (PartVT.isVector()) {
assert(ValueVT.isVector() && "Unknown vector conversion!");
return DAG.getNode(ISD::BIT_CONVERT, dl, ValueVT, Val);
}
if (ValueVT.isVector()) {
assert(ValueVT.getVectorElementType() == PartVT &&
ValueVT.getVectorNumElements() == 1 &&
"Only trivial scalar-to-vector conversions should get here!");
return DAG.getNode(ISD::BUILD_VECTOR, dl, ValueVT, Val);
}
if (PartVT.isInteger() &&
ValueVT.isInteger()) {
if (ValueVT.bitsLT(PartVT)) {
// For a truncate, see if we have any information to
// indicate whether the truncated bits will always be
// zero or sign-extension.
if (AssertOp != ISD::DELETED_NODE)
Val = DAG.getNode(AssertOp, dl, PartVT, Val,
DAG.getValueType(ValueVT));
return DAG.getNode(ISD::TRUNCATE, dl, ValueVT, Val);
} else {
return DAG.getNode(ISD::ANY_EXTEND, dl, ValueVT, Val);
}
}
if (PartVT.isFloatingPoint() && ValueVT.isFloatingPoint()) {
if (ValueVT.bitsLT(Val.getValueType()))
// FP_ROUND's are always exact here.
return DAG.getNode(ISD::FP_ROUND, dl, ValueVT, Val,
DAG.getIntPtrConstant(1));
return DAG.getNode(ISD::FP_EXTEND, dl, ValueVT, Val);
}
if (PartVT.getSizeInBits() == ValueVT.getSizeInBits())
return DAG.getNode(ISD::BIT_CONVERT, dl, ValueVT, Val);
assert(0 && "Unknown mismatch!");
return SDValue();
}
/// getCopyToParts - Create a series of nodes that contain the specified value
/// split into legal parts. If the parts contain more bits than Val, then, for
/// integers, ExtendKind can be used to specify how to generate the extra bits.
static void getCopyToParts(SelectionDAG &DAG, DebugLoc dl, SDValue Val,
SDValue *Parts, unsigned NumParts, MVT PartVT,
ISD::NodeType ExtendKind = ISD::ANY_EXTEND) {
const TargetLowering &TLI = DAG.getTargetLoweringInfo();
MVT PtrVT = TLI.getPointerTy();
MVT ValueVT = Val.getValueType();
unsigned PartBits = PartVT.getSizeInBits();
unsigned OrigNumParts = NumParts;
assert(TLI.isTypeLegal(PartVT) && "Copying to an illegal type!");
if (!NumParts)
return;
if (!ValueVT.isVector()) {
if (PartVT == ValueVT) {
assert(NumParts == 1 && "No-op copy with multiple parts!");
Parts[0] = Val;
return;
}
if (NumParts * PartBits > ValueVT.getSizeInBits()) {
// If the parts cover more bits than the value has, promote the value.
if (PartVT.isFloatingPoint() && ValueVT.isFloatingPoint()) {
assert(NumParts == 1 && "Do not know what to promote to!");
Val = DAG.getNode(ISD::FP_EXTEND, dl, PartVT, Val);
} else if (PartVT.isInteger() && ValueVT.isInteger()) {
ValueVT = MVT::getIntegerVT(NumParts * PartBits);
Val = DAG.getNode(ExtendKind, dl, ValueVT, Val);
} else {
assert(0 && "Unknown mismatch!");
}
} else if (PartBits == ValueVT.getSizeInBits()) {
// Different types of the same size.
assert(NumParts == 1 && PartVT != ValueVT);
Val = DAG.getNode(ISD::BIT_CONVERT, dl, PartVT, Val);
} else if (NumParts * PartBits < ValueVT.getSizeInBits()) {
// If the parts cover less bits than value has, truncate the value.
if (PartVT.isInteger() && ValueVT.isInteger()) {
ValueVT = MVT::getIntegerVT(NumParts * PartBits);
Val = DAG.getNode(ISD::TRUNCATE, dl, ValueVT, Val);
} else {
assert(0 && "Unknown mismatch!");
}
}
// The value may have changed - recompute ValueVT.
ValueVT = Val.getValueType();
assert(NumParts * PartBits == ValueVT.getSizeInBits() &&
"Failed to tile the value with PartVT!");
if (NumParts == 1) {
assert(PartVT == ValueVT && "Type conversion failed!");
Parts[0] = Val;
return;
}
// Expand the value into multiple parts.
if (NumParts & (NumParts - 1)) {
// The number of parts is not a power of 2. Split off and copy the tail.
assert(PartVT.isInteger() && ValueVT.isInteger() &&
"Do not know what to expand to!");
unsigned RoundParts = 1 << Log2_32(NumParts);
unsigned RoundBits = RoundParts * PartBits;
unsigned OddParts = NumParts - RoundParts;
SDValue OddVal = DAG.getNode(ISD::SRL, dl, ValueVT, Val,
DAG.getConstant(RoundBits,
TLI.getPointerTy()));
getCopyToParts(DAG, dl, OddVal, Parts + RoundParts, OddParts, PartVT);
if (TLI.isBigEndian())
// The odd parts were reversed by getCopyToParts - unreverse them.
std::reverse(Parts + RoundParts, Parts + NumParts);
NumParts = RoundParts;
ValueVT = MVT::getIntegerVT(NumParts * PartBits);
Val = DAG.getNode(ISD::TRUNCATE, dl, ValueVT, Val);
}
// The number of parts is a power of 2. Repeatedly bisect the value using
// EXTRACT_ELEMENT.
Parts[0] = DAG.getNode(ISD::BIT_CONVERT, dl,
MVT::getIntegerVT(ValueVT.getSizeInBits()),
Val);
for (unsigned StepSize = NumParts; StepSize > 1; StepSize /= 2) {
for (unsigned i = 0; i < NumParts; i += StepSize) {
unsigned ThisBits = StepSize * PartBits / 2;
MVT ThisVT = MVT::getIntegerVT (ThisBits);
SDValue &Part0 = Parts[i];
SDValue &Part1 = Parts[i+StepSize/2];
Part1 = DAG.getNode(ISD::EXTRACT_ELEMENT, dl,
ThisVT, Part0,
DAG.getConstant(1, PtrVT));
Part0 = DAG.getNode(ISD::EXTRACT_ELEMENT, dl,
ThisVT, Part0,
DAG.getConstant(0, PtrVT));
if (ThisBits == PartBits && ThisVT != PartVT) {
Part0 = DAG.getNode(ISD::BIT_CONVERT, dl,
PartVT, Part0);
Part1 = DAG.getNode(ISD::BIT_CONVERT, dl,
PartVT, Part1);
}
}
}
if (TLI.isBigEndian())
std::reverse(Parts, Parts + OrigNumParts);
return;
}
// Vector ValueVT.
if (NumParts == 1) {
if (PartVT != ValueVT) {
if (PartVT.isVector()) {
Val = DAG.getNode(ISD::BIT_CONVERT, dl, PartVT, Val);
} else {
assert(ValueVT.getVectorElementType() == PartVT &&
ValueVT.getVectorNumElements() == 1 &&
"Only trivial vector-to-scalar conversions should get here!");
Val = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl,
PartVT, Val,
DAG.getConstant(0, PtrVT));
}
}
Parts[0] = Val;
return;
}
// Handle a multi-element vector.
MVT IntermediateVT, RegisterVT;
unsigned NumIntermediates;
unsigned NumRegs = TLI
.getVectorTypeBreakdown(ValueVT, IntermediateVT, NumIntermediates,
RegisterVT);
unsigned NumElements = ValueVT.getVectorNumElements();
assert(NumRegs == NumParts && "Part count doesn't match vector breakdown!");
NumParts = NumRegs; // Silence a compiler warning.
assert(RegisterVT == PartVT && "Part type doesn't match vector breakdown!");
// Split the vector into intermediate operands.
SmallVector<SDValue, 8> Ops(NumIntermediates);
for (unsigned i = 0; i != NumIntermediates; ++i)
if (IntermediateVT.isVector())
Ops[i] = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl,
IntermediateVT, Val,
DAG.getConstant(i * (NumElements / NumIntermediates),
PtrVT));
else
Ops[i] = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl,
IntermediateVT, Val,
DAG.getConstant(i, PtrVT));
// Split the intermediate operands into legal parts.
if (NumParts == NumIntermediates) {
// If the register was not expanded, promote or copy the value,
// as appropriate.
for (unsigned i = 0; i != NumParts; ++i)
getCopyToParts(DAG, dl, Ops[i], &Parts[i], 1, PartVT);
} else if (NumParts > 0) {
// If the intermediate type was expanded, split each the value into
// legal parts.
assert(NumParts % NumIntermediates == 0 &&
"Must expand into a divisible number of parts!");
unsigned Factor = NumParts / NumIntermediates;
for (unsigned i = 0; i != NumIntermediates; ++i)
getCopyToParts(DAG, dl, Ops[i], &Parts[i * Factor], Factor, PartVT);
}
}
void SelectionDAGLowering::init(GCFunctionInfo *gfi, AliasAnalysis &aa) {
AA = &aa;
GFI = gfi;
TD = DAG.getTarget().getTargetData();
}
/// clear - Clear out the curret SelectionDAG and the associated
/// state and prepare this SelectionDAGLowering object to be used
/// for a new block. This doesn't clear out information about
/// additional blocks that are needed to complete switch lowering
/// or PHI node updating; that information is cleared out as it is
/// consumed.
void SelectionDAGLowering::clear() {
NodeMap.clear();
PendingLoads.clear();
PendingExports.clear();
DAG.clear();
CurDebugLoc = DebugLoc::getUnknownLoc();
}
/// getRoot - Return the current virtual root of the Selection DAG,
/// flushing any PendingLoad items. This must be done before emitting
/// a store or any other node that may need to be ordered after any
/// prior load instructions.
///
SDValue SelectionDAGLowering::getRoot() {
if (PendingLoads.empty())
return DAG.getRoot();
if (PendingLoads.size() == 1) {
SDValue Root = PendingLoads[0];
DAG.setRoot(Root);
PendingLoads.clear();
return Root;
}
// Otherwise, we have to make a token factor node.
SDValue Root = DAG.getNode(ISD::TokenFactor, getCurDebugLoc(), MVT::Other,
&PendingLoads[0], PendingLoads.size());
PendingLoads.clear();
DAG.setRoot(Root);
return Root;
}
/// getControlRoot - Similar to getRoot, but instead of flushing all the
/// PendingLoad items, flush all the PendingExports items. It is necessary
/// to do this before emitting a terminator instruction.
///
SDValue SelectionDAGLowering::getControlRoot() {
SDValue Root = DAG.getRoot();
if (PendingExports.empty())
return Root;
// Turn all of the CopyToReg chains into one factored node.
if (Root.getOpcode() != ISD::EntryToken) {
unsigned i = 0, e = PendingExports.size();
for (; i != e; ++i) {
assert(PendingExports[i].getNode()->getNumOperands() > 1);
if (PendingExports[i].getNode()->getOperand(0) == Root)
break; // Don't add the root if we already indirectly depend on it.
}
if (i == e)
PendingExports.push_back(Root);
}
Root = DAG.getNode(ISD::TokenFactor, getCurDebugLoc(), MVT::Other,
&PendingExports[0],
PendingExports.size());
PendingExports.clear();
DAG.setRoot(Root);
return Root;
}
void SelectionDAGLowering::visit(Instruction &I) {
visit(I.getOpcode(), I);
}
void SelectionDAGLowering::visit(unsigned Opcode, User &I) {
// Note: this doesn't use InstVisitor, because it has to work with
// ConstantExpr's in addition to instructions.
switch (Opcode) {
default: assert(0 && "Unknown instruction type encountered!");
abort();
// Build the switch statement using the Instruction.def file.
#define HANDLE_INST(NUM, OPCODE, CLASS) \
case Instruction::OPCODE:return visit##OPCODE((CLASS&)I);
#include "llvm/Instruction.def"
}
}
void SelectionDAGLowering::visitAdd(User &I) {
if (I.getType()->isFPOrFPVector())
visitBinary(I, ISD::FADD);
else
visitBinary(I, ISD::ADD);
}
void SelectionDAGLowering::visitMul(User &I) {
if (I.getType()->isFPOrFPVector())
visitBinary(I, ISD::FMUL);
else
visitBinary(I, ISD::MUL);
}
SDValue SelectionDAGLowering::getValue(const Value *V) {
SDValue &N = NodeMap[V];
if (N.getNode()) return N;
if (Constant *C = const_cast<Constant*>(dyn_cast<Constant>(V))) {
MVT VT = TLI.getValueType(V->getType(), true);
if (ConstantInt *CI = dyn_cast<ConstantInt>(C))
return N = DAG.getConstant(*CI, VT);
if (GlobalValue *GV = dyn_cast<GlobalValue>(C))
return N = DAG.getGlobalAddress(GV, VT);
if (isa<ConstantPointerNull>(C))
return N = DAG.getConstant(0, TLI.getPointerTy());
if (ConstantFP *CFP = dyn_cast<ConstantFP>(C))
return N = DAG.getConstantFP(*CFP, VT);
if (isa<UndefValue>(C) && !V->getType()->isAggregateType())
return N = DAG.getUNDEF(VT);
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
visit(CE->getOpcode(), *CE);
SDValue N1 = NodeMap[V];
assert(N1.getNode() && "visit didn't populate the ValueMap!");
return N1;
}
if (isa<ConstantStruct>(C) || isa<ConstantArray>(C)) {
SmallVector<SDValue, 4> Constants;
for (User::const_op_iterator OI = C->op_begin(), OE = C->op_end();
OI != OE; ++OI) {
SDNode *Val = getValue(*OI).getNode();
for (unsigned i = 0, e = Val->getNumValues(); i != e; ++i)
Constants.push_back(SDValue(Val, i));
}
return DAG.getMergeValues(&Constants[0], Constants.size(),
getCurDebugLoc());
}
if (isa<StructType>(C->getType()) || isa<ArrayType>(C->getType())) {
assert((isa<ConstantAggregateZero>(C) || isa<UndefValue>(C)) &&
"Unknown struct or array constant!");
SmallVector<MVT, 4> ValueVTs;
ComputeValueVTs(TLI, C->getType(), ValueVTs);
unsigned NumElts = ValueVTs.size();
if (NumElts == 0)
return SDValue(); // empty struct
SmallVector<SDValue, 4> Constants(NumElts);
for (unsigned i = 0; i != NumElts; ++i) {
MVT EltVT = ValueVTs[i];
if (isa<UndefValue>(C))
Constants[i] = DAG.getUNDEF(EltVT);
else if (EltVT.isFloatingPoint())
Constants[i] = DAG.getConstantFP(0, EltVT);
else
Constants[i] = DAG.getConstant(0, EltVT);
}
return DAG.getMergeValues(&Constants[0], NumElts, getCurDebugLoc());
}
const VectorType *VecTy = cast<VectorType>(V->getType());
unsigned NumElements = VecTy->getNumElements();
// Now that we know the number and type of the elements, get that number of
// elements into the Ops array based on what kind of constant it is.
SmallVector<SDValue, 16> Ops;
if (ConstantVector *CP = dyn_cast<ConstantVector>(C)) {
for (unsigned i = 0; i != NumElements; ++i)
Ops.push_back(getValue(CP->getOperand(i)));
} else {
assert(isa<ConstantAggregateZero>(C) && "Unknown vector constant!");
MVT EltVT = TLI.getValueType(VecTy->getElementType());
SDValue Op;
if (EltVT.isFloatingPoint())
Op = DAG.getConstantFP(0, EltVT);
else
Op = DAG.getConstant(0, EltVT);
Ops.assign(NumElements, Op);
}
// Create a BUILD_VECTOR node.
return NodeMap[V] = DAG.getNode(ISD::BUILD_VECTOR, getCurDebugLoc(),
VT, &Ops[0], Ops.size());
}
// If this is a static alloca, generate it as the frameindex instead of
// computation.
if (const AllocaInst *AI = dyn_cast<AllocaInst>(V)) {
DenseMap<const AllocaInst*, int>::iterator SI =
FuncInfo.StaticAllocaMap.find(AI);
if (SI != FuncInfo.StaticAllocaMap.end())
return DAG.getFrameIndex(SI->second, TLI.getPointerTy());
}
unsigned InReg = FuncInfo.ValueMap[V];
assert(InReg && "Value not in map!");
RegsForValue RFV(TLI, InReg, V->getType());
SDValue Chain = DAG.getEntryNode();
return RFV.getCopyFromRegs(DAG, getCurDebugLoc(), Chain, NULL);
}
void SelectionDAGLowering::visitRet(ReturnInst &I) {
if (I.getNumOperands() == 0) {
DAG.setRoot(DAG.getNode(ISD::RET, getCurDebugLoc(),
MVT::Other, getControlRoot()));
return;
}
SmallVector<SDValue, 8> NewValues;
NewValues.push_back(getControlRoot());
for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i) {
SmallVector<MVT, 4> ValueVTs;
ComputeValueVTs(TLI, I.getOperand(i)->getType(), ValueVTs);
unsigned NumValues = ValueVTs.size();
if (NumValues == 0) continue;
SDValue RetOp = getValue(I.getOperand(i));
for (unsigned j = 0, f = NumValues; j != f; ++j) {
MVT VT = ValueVTs[j];
ISD::NodeType ExtendKind = ISD::ANY_EXTEND;
const Function *F = I.getParent()->getParent();
if (F->paramHasAttr(0, Attribute::SExt))
ExtendKind = ISD::SIGN_EXTEND;
else if (F->paramHasAttr(0, Attribute::ZExt))
ExtendKind = ISD::ZERO_EXTEND;
// FIXME: C calling convention requires the return type to be promoted to
// at least 32-bit. But this is not necessary for non-C calling
// conventions. The frontend should mark functions whose return values
// require promoting with signext or zeroext attributes.
if (ExtendKind != ISD::ANY_EXTEND && VT.isInteger()) {
MVT MinVT = TLI.getRegisterType(MVT::i32);
if (VT.bitsLT(MinVT))
VT = MinVT;
}
unsigned NumParts = TLI.getNumRegisters(VT);
MVT PartVT = TLI.getRegisterType(VT);
SmallVector<SDValue, 4> Parts(NumParts);
getCopyToParts(DAG, getCurDebugLoc(),
SDValue(RetOp.getNode(), RetOp.getResNo() + j),
&Parts[0], NumParts, PartVT, ExtendKind);
// 'inreg' on function refers to return value
ISD::ArgFlagsTy Flags = ISD::ArgFlagsTy();
if (F->paramHasAttr(0, Attribute::InReg))
Flags.setInReg();
for (unsigned i = 0; i < NumParts; ++i) {
NewValues.push_back(Parts[i]);
NewValues.push_back(DAG.getArgFlags(Flags));
}
}
}
DAG.setRoot(DAG.getNode(ISD::RET, getCurDebugLoc(), MVT::Other,
&NewValues[0], NewValues.size()));
}
/// CopyToExportRegsIfNeeded - If the given value has virtual registers
/// created for it, emit nodes to copy the value into the virtual
/// registers.
void SelectionDAGLowering::CopyToExportRegsIfNeeded(Value *V) {
if (!V->use_empty()) {
DenseMap<const Value *, unsigned>::iterator VMI = FuncInfo.ValueMap.find(V);
if (VMI != FuncInfo.ValueMap.end())
CopyValueToVirtualRegister(V, VMI->second);
}
}
/// ExportFromCurrentBlock - If this condition isn't known to be exported from
/// the current basic block, add it to ValueMap now so that we'll get a
/// CopyTo/FromReg.
void SelectionDAGLowering::ExportFromCurrentBlock(Value *V) {
// No need to export constants.
if (!isa<Instruction>(V) && !isa<Argument>(V)) return;
// Already exported?
if (FuncInfo.isExportedInst(V)) return;
unsigned Reg = FuncInfo.InitializeRegForValue(V);
CopyValueToVirtualRegister(V, Reg);
}
bool SelectionDAGLowering::isExportableFromCurrentBlock(Value *V,
const BasicBlock *FromBB) {
// The operands of the setcc have to be in this block. We don't know
// how to export them from some other block.
if (Instruction *VI = dyn_cast<Instruction>(V)) {
// Can export from current BB.
if (VI->getParent() == FromBB)
return true;
// Is already exported, noop.
return FuncInfo.isExportedInst(V);
}
// If this is an argument, we can export it if the BB is the entry block or
// if it is already exported.
if (isa<Argument>(V)) {
if (FromBB == &FromBB->getParent()->getEntryBlock())
return true;
// Otherwise, can only export this if it is already exported.
return FuncInfo.isExportedInst(V);
}
// Otherwise, constants can always be exported.
return true;
}
static bool InBlock(const Value *V, const BasicBlock *BB) {
if (const Instruction *I = dyn_cast<Instruction>(V))
return I->getParent() == BB;
return true;
}
/// getFCmpCondCode - Return the ISD condition code corresponding to
/// the given LLVM IR floating-point condition code. This includes
/// consideration of global floating-point math flags.
///
static ISD::CondCode getFCmpCondCode(FCmpInst::Predicate Pred) {
ISD::CondCode FPC, FOC;
switch (Pred) {
case FCmpInst::FCMP_FALSE: FOC = FPC = ISD::SETFALSE; break;
case FCmpInst::FCMP_OEQ: FOC = ISD::SETEQ; FPC = ISD::SETOEQ; break;
case FCmpInst::FCMP_OGT: FOC = ISD::SETGT; FPC = ISD::SETOGT; break;
case FCmpInst::FCMP_OGE: FOC = ISD::SETGE; FPC = ISD::SETOGE; break;
case FCmpInst::FCMP_OLT: FOC = ISD::SETLT; FPC = ISD::SETOLT; break;
case FCmpInst::FCMP_OLE: FOC = ISD::SETLE; FPC = ISD::SETOLE; break;
case FCmpInst::FCMP_ONE: FOC = ISD::SETNE; FPC = ISD::SETONE; break;
case FCmpInst::FCMP_ORD: FOC = FPC = ISD::SETO; break;
case FCmpInst::FCMP_UNO: FOC = FPC = ISD::SETUO; break;
case FCmpInst::FCMP_UEQ: FOC = ISD::SETEQ; FPC = ISD::SETUEQ; break;
case FCmpInst::FCMP_UGT: FOC = ISD::SETGT; FPC = ISD::SETUGT; break;
case FCmpInst::FCMP_UGE: FOC = ISD::SETGE; FPC = ISD::SETUGE; break;
case FCmpInst::FCMP_ULT: FOC = ISD::SETLT; FPC = ISD::SETULT; break;
case FCmpInst::FCMP_ULE: FOC = ISD::SETLE; FPC = ISD::SETULE; break;
case FCmpInst::FCMP_UNE: FOC = ISD::SETNE; FPC = ISD::SETUNE; break;
case FCmpInst::FCMP_TRUE: FOC = FPC = ISD::SETTRUE; break;
default:
assert(0 && "Invalid FCmp predicate opcode!");
FOC = FPC = ISD::SETFALSE;
break;
}
if (FiniteOnlyFPMath())
return FOC;
else
return FPC;
}
/// getICmpCondCode - Return the ISD condition code corresponding to
/// the given LLVM IR integer condition code.
///
static ISD::CondCode getICmpCondCode(ICmpInst::Predicate Pred) {
switch (Pred) {
case ICmpInst::ICMP_EQ: return ISD::SETEQ;
case ICmpInst::ICMP_NE: return ISD::SETNE;
case ICmpInst::ICMP_SLE: return ISD::SETLE;
case ICmpInst::ICMP_ULE: return ISD::SETULE;
case ICmpInst::ICMP_SGE: return ISD::SETGE;
case ICmpInst::ICMP_UGE: return ISD::SETUGE;
case ICmpInst::ICMP_SLT: return ISD::SETLT;
case ICmpInst::ICMP_ULT: return ISD::SETULT;
case ICmpInst::ICMP_SGT: return ISD::SETGT;
case ICmpInst::ICMP_UGT: return ISD::SETUGT;
default:
assert(0 && "Invalid ICmp predicate opcode!");
return ISD::SETNE;
}
}
/// EmitBranchForMergedCondition - Helper method for FindMergedConditions.
/// This function emits a branch and is used at the leaves of an OR or an
/// AND operator tree.
///
void
SelectionDAGLowering::EmitBranchForMergedCondition(Value *Cond,
MachineBasicBlock *TBB,
MachineBasicBlock *FBB,
MachineBasicBlock *CurBB) {
const BasicBlock *BB = CurBB->getBasicBlock();
// If the leaf of the tree is a comparison, merge the condition into
// the caseblock.
if (CmpInst *BOp = dyn_cast<CmpInst>(Cond)) {
// The operands of the cmp have to be in this block. We don't know
// how to export them from some other block. If this is the first block
// of the sequence, no exporting is needed.
if (CurBB == CurMBB ||
(isExportableFromCurrentBlock(BOp->getOperand(0), BB) &&
isExportableFromCurrentBlock(BOp->getOperand(1), BB))) {
ISD::CondCode Condition;
if (ICmpInst *IC = dyn_cast<ICmpInst>(Cond)) {
Condition = getICmpCondCode(IC->getPredicate());
} else if (FCmpInst *FC = dyn_cast<FCmpInst>(Cond)) {
Condition = getFCmpCondCode(FC->getPredicate());
} else {
Condition = ISD::SETEQ; // silence warning.
assert(0 && "Unknown compare instruction");
}
CaseBlock CB(Condition, BOp->getOperand(0),
BOp->getOperand(1), NULL, TBB, FBB, CurBB);
SwitchCases.push_back(CB);
return;
}
}
// Create a CaseBlock record representing this branch.
CaseBlock CB(ISD::SETEQ, Cond, ConstantInt::getTrue(),
NULL, TBB, FBB, CurBB);
SwitchCases.push_back(CB);
}
/// FindMergedConditions - If Cond is an expression like
void SelectionDAGLowering::FindMergedConditions(Value *Cond,
MachineBasicBlock *TBB,
MachineBasicBlock *FBB,
MachineBasicBlock *CurBB,
unsigned Opc) {
// If this node is not part of the or/and tree, emit it as a branch.
Instruction *BOp = dyn_cast<Instruction>(Cond);
if (!BOp || !(isa<BinaryOperator>(BOp) || isa<CmpInst>(BOp)) ||
(unsigned)BOp->getOpcode() != Opc || !BOp->hasOneUse() ||
BOp->getParent() != CurBB->getBasicBlock() ||
!InBlock(BOp->getOperand(0), CurBB->getBasicBlock()) ||
!InBlock(BOp->getOperand(1), CurBB->getBasicBlock())) {
EmitBranchForMergedCondition(Cond, TBB, FBB, CurBB);
return;
}
// Create TmpBB after CurBB.
MachineFunction::iterator BBI = CurBB;
MachineFunction &MF = DAG.getMachineFunction();
MachineBasicBlock *TmpBB = MF.CreateMachineBasicBlock(CurBB->getBasicBlock());
CurBB->getParent()->insert(++BBI, TmpBB);
if (Opc == Instruction::Or) {
// Codegen X | Y as:
// jmp_if_X TBB
// jmp TmpBB
// TmpBB:
// jmp_if_Y TBB
// jmp FBB
//
// Emit the LHS condition.
FindMergedConditions(BOp->getOperand(0), TBB, TmpBB, CurBB, Opc);
// Emit the RHS condition into TmpBB.
FindMergedConditions(BOp->getOperand(1), TBB, FBB, TmpBB, Opc);
} else {
assert(Opc == Instruction::And && "Unknown merge op!");
// Codegen X & Y as:
// jmp_if_X TmpBB
// jmp FBB
// TmpBB:
// jmp_if_Y TBB
// jmp FBB
//
// This requires creation of TmpBB after CurBB.
// Emit the LHS condition.
FindMergedConditions(BOp->getOperand(0), TmpBB, FBB, CurBB, Opc);
// Emit the RHS condition into TmpBB.
FindMergedConditions(BOp->getOperand(1), TBB, FBB, TmpBB, Opc);
}
}
/// If the set of cases should be emitted as a series of branches, return true.
/// If we should emit this as a bunch of and/or'd together conditions, return
/// false.
bool
SelectionDAGLowering::ShouldEmitAsBranches(const std::vector<CaseBlock> &Cases){
if (Cases.size() != 2) return true;
// If this is two comparisons of the same values or'd or and'd together, they
// will get folded into a single comparison, so don't emit two blocks.
if ((Cases[0].CmpLHS == Cases[1].CmpLHS &&
Cases[0].CmpRHS == Cases[1].CmpRHS) ||
(Cases[0].CmpRHS == Cases[1].CmpLHS &&
Cases[0].CmpLHS == Cases[1].CmpRHS)) {
return false;
}
return true;
}
void SelectionDAGLowering::visitBr(BranchInst &I) {
// Update machine-CFG edges.
MachineBasicBlock *Succ0MBB = FuncInfo.MBBMap[I.getSuccessor(0)];
// Figure out which block is immediately after the current one.
MachineBasicBlock *NextBlock = 0;
MachineFunction::iterator BBI = CurMBB;
if (++BBI != CurMBB->getParent()->end())
NextBlock = BBI;
if (I.isUnconditional()) {
// Update machine-CFG edges.
CurMBB->addSuccessor(Succ0MBB);
// If this is not a fall-through branch, emit the branch.
if (Succ0MBB != NextBlock)
DAG.setRoot(DAG.getNode(ISD::BR, getCurDebugLoc(),
MVT::Other, getControlRoot(),
DAG.getBasicBlock(Succ0MBB)));
return;
}
// If this condition is one of the special cases we handle, do special stuff
// now.
Value *CondVal = I.getCondition();
MachineBasicBlock *Succ1MBB = FuncInfo.MBBMap[I.getSuccessor(1)];
// If this is a series of conditions that are or'd or and'd together, emit
// this as a sequence of branches instead of setcc's with and/or operations.
// For example, instead of something like:
// cmp A, B
// C = seteq
// cmp D, E
// F = setle
// or C, F
// jnz foo
// Emit:
// cmp A, B
// je foo
// cmp D, E
// jle foo
//
if (BinaryOperator *BOp = dyn_cast<BinaryOperator>(CondVal)) {
if (BOp->hasOneUse() &&
(BOp->getOpcode() == Instruction::And ||
BOp->getOpcode() == Instruction::Or)) {
FindMergedConditions(BOp, Succ0MBB, Succ1MBB, CurMBB, BOp->getOpcode());
// If the compares in later blocks need to use values not currently
// exported from this block, export them now. This block should always
// be the first entry.
assert(SwitchCases[0].ThisBB == CurMBB && "Unexpected lowering!");
// Allow some cases to be rejected.
if (ShouldEmitAsBranches(SwitchCases)) {
for (unsigned i = 1, e = SwitchCases.size(); i != e; ++i) {
ExportFromCurrentBlock(SwitchCases[i].CmpLHS);
ExportFromCurrentBlock(SwitchCases[i].CmpRHS);
}
// Emit the branch for this block.
visitSwitchCase(SwitchCases[0]);
SwitchCases.erase(SwitchCases.begin());
return;
}
// Okay, we decided not to do this, remove any inserted MBB's and clear
// SwitchCases.
for (unsigned i = 1, e = SwitchCases.size(); i != e; ++i)
CurMBB->getParent()->erase(SwitchCases[i].ThisBB);
SwitchCases.clear();
}
}
// Create a CaseBlock record representing this branch.
CaseBlock CB(ISD::SETEQ, CondVal, ConstantInt::getTrue(),
NULL, Succ0MBB, Succ1MBB, CurMBB);
// Use visitSwitchCase to actually insert the fast branch sequence for this
// cond branch.
visitSwitchCase(CB);
}
/// visitSwitchCase - Emits the necessary code to represent a single node in
/// the binary search tree resulting from lowering a switch instruction.
void SelectionDAGLowering::visitSwitchCase(CaseBlock &CB) {
SDValue Cond;
SDValue CondLHS = getValue(CB.CmpLHS);
DebugLoc dl = getCurDebugLoc();
// Build the setcc now.
if (CB.CmpMHS == NULL) {
// Fold "(X == true)" to X and "(X == false)" to !X to
// handle common cases produced by branch lowering.
if (CB.CmpRHS == ConstantInt::getTrue() && CB.CC == ISD::SETEQ)
Cond = CondLHS;
else if (CB.CmpRHS == ConstantInt::getFalse() && CB.CC == ISD::SETEQ) {
SDValue True = DAG.getConstant(1, CondLHS.getValueType());
Cond = DAG.getNode(ISD::XOR, dl, CondLHS.getValueType(), CondLHS, True);
} else
Cond = DAG.getSetCC(dl, MVT::i1, CondLHS, getValue(CB.CmpRHS), CB.CC);
} else {
assert(CB.CC == ISD::SETLE && "Can handle only LE ranges now");
const APInt& Low = cast<ConstantInt>(CB.CmpLHS)->getValue();
const APInt& High = cast<ConstantInt>(CB.CmpRHS)->getValue();
SDValue CmpOp = getValue(CB.CmpMHS);
MVT VT = CmpOp.getValueType();
if (cast<ConstantInt>(CB.CmpLHS)->isMinValue(true)) {
Cond = DAG.getSetCC(dl, MVT::i1, CmpOp, DAG.getConstant(High, VT),
ISD::SETLE);
} else {
SDValue SUB = DAG.getNode(ISD::SUB, dl,
VT, CmpOp, DAG.getConstant(Low, VT));
Cond = DAG.getSetCC(dl, MVT::i1, SUB,
DAG.getConstant(High-Low, VT), ISD::SETULE);
}
}
// Update successor info
CurMBB->addSuccessor(CB.TrueBB);
CurMBB->addSuccessor(CB.FalseBB);
// Set NextBlock to be the MBB immediately after the current one, if any.
// This is used to avoid emitting unnecessary branches to the next block.
MachineBasicBlock *NextBlock = 0;
MachineFunction::iterator BBI = CurMBB;
if (++BBI != CurMBB->getParent()->end())
NextBlock = BBI;
// If the lhs block is the next block, invert the condition so that we can
// fall through to the lhs instead of the rhs block.
if (CB.TrueBB == NextBlock) {
std::swap(CB.TrueBB, CB.FalseBB);
SDValue True = DAG.getConstant(1, Cond.getValueType());
Cond = DAG.getNode(ISD::XOR, dl, Cond.getValueType(), Cond, True);
}
SDValue BrCond = DAG.getNode(ISD::BRCOND, dl,
MVT::Other, getControlRoot(), Cond,
DAG.getBasicBlock(CB.TrueBB));
// If the branch was constant folded, fix up the CFG.
if (BrCond.getOpcode() == ISD::BR) {
CurMBB->removeSuccessor(CB.FalseBB);
DAG.setRoot(BrCond);
} else {
// Otherwise, go ahead and insert the false branch.
if (BrCond == getControlRoot())
CurMBB->removeSuccessor(CB.TrueBB);
if (CB.FalseBB == NextBlock)
DAG.setRoot(BrCond);
else
DAG.setRoot(DAG.getNode(ISD::BR, dl, MVT::Other, BrCond,
DAG.getBasicBlock(CB.FalseBB)));
}
}
/// visitJumpTable - Emit JumpTable node in the current MBB
void SelectionDAGLowering::visitJumpTable(JumpTable &JT) {
// Emit the code for the jump table
assert(JT.Reg != -1U && "Should lower JT Header first!");
MVT PTy = TLI.getPointerTy();
SDValue Index = DAG.getCopyFromReg(getControlRoot(), getCurDebugLoc(),
JT.Reg, PTy);
SDValue Table = DAG.getJumpTable(JT.JTI, PTy);
DAG.setRoot(DAG.getNode(ISD::BR_JT, getCurDebugLoc(),
MVT::Other, Index.getValue(1),
Table, Index));
}
/// visitJumpTableHeader - This function emits necessary code to produce index
/// in the JumpTable from switch case.
void SelectionDAGLowering::visitJumpTableHeader(JumpTable &JT,
JumpTableHeader &JTH) {
// Subtract the lowest switch case value from the value being switched on and
// conditional branch to default mbb if the result is greater than the
// difference between smallest and largest cases.
SDValue SwitchOp = getValue(JTH.SValue);
MVT VT = SwitchOp.getValueType();
SDValue SUB = DAG.getNode(ISD::SUB, getCurDebugLoc(), VT, SwitchOp,
DAG.getConstant(JTH.First, VT));
// The SDNode we just created, which holds the value being switched on minus
// the the smallest case value, needs to be copied to a virtual register so it
// can be used as an index into the jump table in a subsequent basic block.
// This value may be smaller or larger than the target's pointer type, and
// therefore require extension or truncating.
if (VT.bitsGT(TLI.getPointerTy()))
SwitchOp = DAG.getNode(ISD::TRUNCATE, getCurDebugLoc(),
TLI.getPointerTy(), SUB);
else
SwitchOp = DAG.getNode(ISD::ZERO_EXTEND, getCurDebugLoc(),
TLI.getPointerTy(), SUB);
unsigned JumpTableReg = FuncInfo.MakeReg(TLI.getPointerTy());
SDValue CopyTo = DAG.getCopyToReg(getControlRoot(), getCurDebugLoc(),
JumpTableReg, SwitchOp);
JT.Reg = JumpTableReg;
// Emit the range check for the jump table, and branch to the default block
// for the switch statement if the value being switched on exceeds the largest
// case in the switch.
SDValue CMP = DAG.getSetCC(getCurDebugLoc(),
TLI.getSetCCResultType(SUB.getValueType()), SUB,
DAG.getConstant(JTH.Last-JTH.First,VT),
ISD::SETUGT);
// Set NextBlock to be the MBB immediately after the current one, if any.
// This is used to avoid emitting unnecessary branches to the next block.
MachineBasicBlock *NextBlock = 0;
MachineFunction::iterator BBI = CurMBB;
if (++BBI != CurMBB->getParent()->end())
NextBlock = BBI;
SDValue BrCond = DAG.getNode(ISD::BRCOND, getCurDebugLoc(),
MVT::Other, CopyTo, CMP,
DAG.getBasicBlock(JT.Default));
if (JT.MBB == NextBlock)
DAG.setRoot(BrCond);
else
DAG.setRoot(DAG.getNode(ISD::BR, getCurDebugLoc(), MVT::Other, BrCond,
DAG.getBasicBlock(JT.MBB)));
}
/// visitBitTestHeader - This function emits necessary code to produce value
/// suitable for "bit tests"
void SelectionDAGLowering::visitBitTestHeader(BitTestBlock &B) {
// Subtract the minimum value
SDValue SwitchOp = getValue(B.SValue);
MVT VT = SwitchOp.getValueType();
SDValue SUB = DAG.getNode(ISD::SUB, getCurDebugLoc(), VT, SwitchOp,
DAG.getConstant(B.First, VT));
// Check range
SDValue RangeCmp = DAG.getSetCC(getCurDebugLoc(),
TLI.getSetCCResultType(SUB.getValueType()),
SUB, DAG.getConstant(B.Range, VT),
ISD::SETUGT);
SDValue ShiftOp;
if (VT.bitsGT(TLI.getPointerTy()))
ShiftOp = DAG.getNode(ISD::TRUNCATE, getCurDebugLoc(),
TLI.getPointerTy(), SUB);
else
ShiftOp = DAG.getNode(ISD::ZERO_EXTEND, getCurDebugLoc(),
TLI.getPointerTy(), SUB);
B.Reg = FuncInfo.MakeReg(TLI.getPointerTy());
SDValue CopyTo = DAG.getCopyToReg(getControlRoot(), getCurDebugLoc(),
B.Reg, ShiftOp);
// Set NextBlock to be the MBB immediately after the current one, if any.
// This is used to avoid emitting unnecessary branches to the next block.
MachineBasicBlock *NextBlock = 0;
MachineFunction::iterator BBI = CurMBB;
if (++BBI != CurMBB->getParent()->end())
NextBlock = BBI;
MachineBasicBlock* MBB = B.Cases[0].ThisBB;
CurMBB->addSuccessor(B.Default);
CurMBB->addSuccessor(MBB);
SDValue BrRange = DAG.getNode(ISD::BRCOND, getCurDebugLoc(),
MVT::Other, CopyTo, RangeCmp,
DAG.getBasicBlock(B.Default));
if (MBB == NextBlock)
DAG.setRoot(BrRange);
else
DAG.setRoot(DAG.getNode(ISD::BR, getCurDebugLoc(), MVT::Other, CopyTo,
DAG.getBasicBlock(MBB)));
}
/// visitBitTestCase - this function produces one "bit test"
void SelectionDAGLowering::visitBitTestCase(MachineBasicBlock* NextMBB,
unsigned Reg,
BitTestCase &B) {
// Make desired shift
SDValue ShiftOp = DAG.getCopyFromReg(getControlRoot(), getCurDebugLoc(), Reg,
TLI.getPointerTy());
SDValue SwitchVal = DAG.getNode(ISD::SHL, getCurDebugLoc(),
TLI.getPointerTy(),
DAG.getConstant(1, TLI.getPointerTy()),
ShiftOp);
// Emit bit tests and jumps
SDValue AndOp = DAG.getNode(ISD::AND, getCurDebugLoc(),
TLI.getPointerTy(), SwitchVal,
DAG.getConstant(B.Mask, TLI.getPointerTy()));
SDValue AndCmp = DAG.getSetCC(getCurDebugLoc(),
TLI.getSetCCResultType(AndOp.getValueType()),
AndOp, DAG.getConstant(0, TLI.getPointerTy()),
ISD::SETNE);
CurMBB->addSuccessor(B.TargetBB);
CurMBB->addSuccessor(NextMBB);
SDValue BrAnd = DAG.getNode(ISD::BRCOND, getCurDebugLoc(),
MVT::Other, getControlRoot(),
AndCmp, DAG.getBasicBlock(B.TargetBB));
// Set NextBlock to be the MBB immediately after the current one, if any.
// This is used to avoid emitting unnecessary branches to the next block.
MachineBasicBlock *NextBlock = 0;
MachineFunction::iterator BBI = CurMBB;
if (++BBI != CurMBB->getParent()->end())
NextBlock = BBI;
if (NextMBB == NextBlock)
DAG.setRoot(BrAnd);
else
DAG.setRoot(DAG.getNode(ISD::BR, getCurDebugLoc(), MVT::Other, BrAnd,
DAG.getBasicBlock(NextMBB)));
}
void SelectionDAGLowering::visitInvoke(InvokeInst &I) {
// Retrieve successors.
MachineBasicBlock *Return = FuncInfo.MBBMap[I.getSuccessor(0)];
MachineBasicBlock *LandingPad = FuncInfo.MBBMap[I.getSuccessor(1)];
const Value *Callee(I.getCalledValue());
if (isa<InlineAsm>(Callee))
visitInlineAsm(&I);
else
LowerCallTo(&I, getValue(Callee), false, LandingPad);
// If the value of the invoke is used outside of its defining block, make it
// available as a virtual register.
CopyToExportRegsIfNeeded(&I);
// Update successor info
CurMBB->addSuccessor(Return);
CurMBB->addSuccessor(LandingPad);
// Drop into normal successor.
DAG.setRoot(DAG.getNode(ISD::BR, getCurDebugLoc(),
MVT::Other, getControlRoot(),
DAG.getBasicBlock(Return)));
}
void SelectionDAGLowering::visitUnwind(UnwindInst &I) {
}
/// handleSmallSwitchCaseRange - Emit a series of specific tests (suitable for
/// small case ranges).
bool SelectionDAGLowering::handleSmallSwitchRange(CaseRec& CR,
CaseRecVector& WorkList,
Value* SV,
MachineBasicBlock* Default) {
Case& BackCase = *(CR.Range.second-1);
// Size is the number of Cases represented by this range.
size_t Size = CR.Range.second - CR.Range.first;
if (Size > 3)
return false;
// Get the MachineFunction which holds the current MBB. This is used when
// inserting any additional MBBs necessary to represent the switch.
MachineFunction *CurMF = CurMBB->getParent();
// Figure out which block is immediately after the current one.
MachineBasicBlock *NextBlock = 0;
MachineFunction::iterator BBI = CR.CaseBB;
if (++BBI != CurMBB->getParent()->end())
NextBlock = BBI;
// TODO: If any two of the cases has the same destination, and if one value
// is the same as the other, but has one bit unset that the other has set,
// use bit manipulation to do two compares at once. For example:
// "if (X == 6 || X == 4)" -> "if ((X|2) == 6)"
// Rearrange the case blocks so that the last one falls through if possible.
if (NextBlock && Default != NextBlock && BackCase.BB != NextBlock) {
// The last case block won't fall through into 'NextBlock' if we emit the
// branches in this order. See if rearranging a case value would help.
for (CaseItr I = CR.Range.first, E = CR.Range.second-1; I != E; ++I) {
if (I->BB == NextBlock) {
std::swap(*I, BackCase);
break;
}
}
}
// Create a CaseBlock record representing a conditional branch to
// the Case's target mbb if the value being switched on SV is equal
// to C.
MachineBasicBlock *CurBlock = CR.CaseBB;
for (CaseItr I = CR.Range.first, E = CR.Range.second; I != E; ++I) {
MachineBasicBlock *FallThrough;
if (I != E-1) {
FallThrough = CurMF->CreateMachineBasicBlock(CurBlock->getBasicBlock());
CurMF->insert(BBI, FallThrough);
// Put SV in a virtual register to make it available from the new blocks.
ExportFromCurrentBlock(SV);
} else {
// If the last case doesn't match, go to the default block.
FallThrough = Default;
}
Value *RHS, *LHS, *MHS;
ISD::CondCode CC;
if (I->High == I->Low) {
// This is just small small case range :) containing exactly 1 case
CC = ISD::SETEQ;
LHS = SV; RHS = I->High; MHS = NULL;
} else {
CC = ISD::SETLE;
LHS = I->Low; MHS = SV; RHS = I->High;
}
CaseBlock CB(CC, LHS, RHS, MHS, I->BB, FallThrough, CurBlock);
// If emitting the first comparison, just call visitSwitchCase to emit the
// code into the current block. Otherwise, push the CaseBlock onto the
// vector to be later processed by SDISel, and insert the node's MBB
// before the next MBB.
if (CurBlock == CurMBB)
visitSwitchCase(CB);
else
SwitchCases.push_back(CB);
CurBlock = FallThrough;
}
return true;
}
static inline bool areJTsAllowed(const TargetLowering &TLI) {
return !DisableJumpTables &&
(TLI.isOperationLegalOrCustom(ISD::BR_JT, MVT::Other) ||
TLI.isOperationLegalOrCustom(ISD::BRIND, MVT::Other));
}
static APInt ComputeRange(const APInt &First, const APInt &Last) {
APInt LastExt(Last), FirstExt(First);
uint32_t BitWidth = std::max(Last.getBitWidth(), First.getBitWidth()) + 1;
LastExt.sext(BitWidth); FirstExt.sext(BitWidth);
return (LastExt - FirstExt + 1ULL);
}
/// handleJTSwitchCase - Emit jumptable for current switch case range
bool SelectionDAGLowering::handleJTSwitchCase(CaseRec& CR,
CaseRecVector& WorkList,
Value* SV,
MachineBasicBlock* Default) {
Case& FrontCase = *CR.Range.first;
Case& BackCase = *(CR.Range.second-1);
const APInt& First = cast<ConstantInt>(FrontCase.Low)->getValue();
const APInt& Last = cast<ConstantInt>(BackCase.High)->getValue();
size_t TSize = 0;
for (CaseItr I = CR.Range.first, E = CR.Range.second;
I!=E; ++I)
TSize += I->size();
if (!areJTsAllowed(TLI) || TSize <= 3)
return false;
APInt Range = ComputeRange(First, Last);
double Density = (double)TSize / Range.roundToDouble();
if (Density < 0.4)
return false;
DEBUG(errs() << "Lowering jump table\n"
<< "First entry: " << First << ". Last entry: " << Last << '\n'
<< "Range: " << Range
<< "Size: " << TSize << ". Density: " << Density << "\n\n");
// Get the MachineFunction which holds the current MBB. This is used when
// inserting any additional MBBs necessary to represent the switch.
MachineFunction *CurMF = CurMBB->getParent();
// Figure out which block is immediately after the current one.
MachineBasicBlock *NextBlock = 0;
MachineFunction::iterator BBI = CR.CaseBB;
if (++BBI != CurMBB->getParent()->end())
NextBlock = BBI;
const BasicBlock *LLVMBB = CR.CaseBB->getBasicBlock();
// Create a new basic block to hold the code for loading the address
// of the jump table, and jumping to it. Update successor information;
// we will either branch to the default case for the switch, or the jump
// table.
MachineBasicBlock *JumpTableBB = CurMF->CreateMachineBasicBlock(LLVMBB);
CurMF->insert(BBI, JumpTableBB);
CR.CaseBB->addSuccessor(Default);
CR.CaseBB->addSuccessor(JumpTableBB);
// Build a vector of destination BBs, corresponding to each target
// of the jump table. If the value of the jump table slot corresponds to
// a case statement, push the case's BB onto the vector, otherwise, push
// the default BB.
std::vector<MachineBasicBlock*> DestBBs;
APInt TEI = First;
for (CaseItr I = CR.Range.first, E = CR.Range.second; I != E; ++TEI) {
const APInt& Low = cast<ConstantInt>(I->Low)->getValue();
const APInt& High = cast<ConstantInt>(I->High)->getValue();
if (Low.sle(TEI) && TEI.sle(High)) {
DestBBs.push_back(I->BB);
if (TEI==High)
++I;
} else {
DestBBs.push_back(Default);
}
}
// Update successor info. Add one edge to each unique successor.
BitVector SuccsHandled(CR.CaseBB->getParent()->getNumBlockIDs());
for (std::vector<MachineBasicBlock*>::iterator I = DestBBs.begin(),
E = DestBBs.end(); I != E; ++I) {
if (!SuccsHandled[(*I)->getNumber()]) {
SuccsHandled[(*I)->getNumber()] = true;
JumpTableBB->addSuccessor(*I);
}
}
// Create a jump table index for this jump table, or return an existing
// one.
unsigned JTI = CurMF->getJumpTableInfo()->getJumpTableIndex(DestBBs);
// Set the jump table information so that we can codegen it as a second
// MachineBasicBlock
JumpTable JT(-1U, JTI, JumpTableBB, Default);
JumpTableHeader JTH(First, Last, SV, CR.CaseBB, (CR.CaseBB == CurMBB));
if (CR.CaseBB == CurMBB)
visitJumpTableHeader(JT, JTH);
JTCases.push_back(JumpTableBlock(JTH, JT));
return true;
}
/// handleBTSplitSwitchCase - emit comparison and split binary search tree into
/// 2 subtrees.
bool SelectionDAGLowering::handleBTSplitSwitchCase(CaseRec& CR,
CaseRecVector& WorkList,
Value* SV,
MachineBasicBlock* Default) {
// Get the MachineFunction which holds the current MBB. This is used when
// inserting any additional MBBs necessary to represent the switch.
MachineFunction *CurMF = CurMBB->getParent();
// Figure out which block is immediately after the current one.
MachineBasicBlock *NextBlock = 0;
MachineFunction::iterator BBI = CR.CaseBB;
if (++BBI != CurMBB->getParent()->end())
NextBlock = BBI;
Case& FrontCase = *CR.Range.first;
Case& BackCase = *(CR.Range.second-1);
const BasicBlock *LLVMBB = CR.CaseBB->getBasicBlock();
// Size is the number of Cases represented by this range.
unsigned Size = CR.Range.second - CR.Range.first;
const APInt& First = cast<ConstantInt>(FrontCase.Low)->getValue();
const APInt& Last = cast<ConstantInt>(BackCase.High)->getValue();
double FMetric = 0;
CaseItr Pivot = CR.Range.first + Size/2;
// Select optimal pivot, maximizing sum density of LHS and RHS. This will
// (heuristically) allow us to emit JumpTable's later.
size_t TSize = 0;
for (CaseItr I = CR.Range.first, E = CR.Range.second;
I!=E; ++I)
TSize += I->size();
size_t LSize = FrontCase.size();
size_t RSize = TSize-LSize;
DEBUG(errs() << "Selecting best pivot: \n"
<< "First: " << First << ", Last: " << Last <<'\n'
<< "LSize: " << LSize << ", RSize: " << RSize << '\n');
for (CaseItr I = CR.Range.first, J=I+1, E = CR.Range.second;
J!=E; ++I, ++J) {
const APInt& LEnd = cast<ConstantInt>(I->High)->getValue();
const APInt& RBegin = cast<ConstantInt>(J->Low)->getValue();
APInt Range = ComputeRange(LEnd, RBegin);
assert((Range - 2ULL).isNonNegative() &&
"Invalid case distance");
double LDensity = (double)LSize / (LEnd - First + 1ULL).roundToDouble();
double RDensity = (double)RSize / (Last - RBegin + 1ULL).roundToDouble();
double Metric = Range.logBase2()*(LDensity+RDensity);
// Should always split in some non-trivial place
DEBUG(errs() <<"=>Step\n"
<< "LEnd: " << LEnd << ", RBegin: " << RBegin << '\n'
<< "LDensity: " << LDensity
<< ", RDensity: " << RDensity << '\n'
<< "Metric: " << Metric << '\n');
if (FMetric < Metric) {
Pivot = J;
FMetric = Metric;
DEBUG(errs() << "Current metric set to: " << FMetric << '\n');
}
LSize += J->size();
RSize -= J->size();
}
if (areJTsAllowed(TLI)) {
// If our case is dense we *really* should handle it earlier!
assert((FMetric > 0) && "Should handle dense range earlier!");
} else {
Pivot = CR.Range.first + Size/2;
}
CaseRange LHSR(CR.Range.first, Pivot);
CaseRange RHSR(Pivot, CR.Range.second);
Constant *C = Pivot->Low;
MachineBasicBlock *FalseBB = 0, *TrueBB = 0;
// We know that we branch to the LHS if the Value being switched on is
// less than the Pivot value, C. We use this to optimize our binary
// tree a bit, by recognizing that if SV is greater than or equal to the
// LHS's Case Value, and that Case Value is exactly one less than the
// Pivot's Value, then we can branch directly to the LHS's Target,
// rather than creating a leaf node for it.
if ((LHSR.second - LHSR.first) == 1 &&
LHSR.first->High == CR.GE &&
cast<ConstantInt>(C)->getValue() ==
(cast<ConstantInt>(CR.GE)->getValue() + 1LL)) {
TrueBB = LHSR.first->BB;
} else {
TrueBB = CurMF->CreateMachineBasicBlock(LLVMBB);
CurMF->insert(BBI, TrueBB);
WorkList.push_back(CaseRec(TrueBB, C, CR.GE, LHSR));
// Put SV in a virtual register to make it available from the new blocks.
ExportFromCurrentBlock(SV);
}
// Similar to the optimization above, if the Value being switched on is
// known to be less than the Constant CR.LT, and the current Case Value
// is CR.LT - 1, then we can branch directly to the target block for
// the current Case Value, rather than emitting a RHS leaf node for it.
if ((RHSR.second - RHSR.first) == 1 && CR.LT &&
cast<ConstantInt>(RHSR.first->Low)->getValue() ==
(cast<ConstantInt>(CR.LT)->getValue() - 1LL)) {
FalseBB = RHSR.first->BB;
} else {
FalseBB = CurMF->CreateMachineBasicBlock(LLVMBB);
CurMF->insert(BBI, FalseBB);
WorkList.push_back(CaseRec(FalseBB,CR.LT,C,RHSR));
// Put SV in a virtual register to make it available from the new blocks.
ExportFromCurrentBlock(SV);
}
// Create a CaseBlock record representing a conditional branch to
// the LHS node if the value being switched on SV is less than C.
// Otherwise, branch to LHS.
CaseBlock CB(ISD::SETLT, SV, C, NULL, TrueBB, FalseBB, CR.CaseBB);
if (CR.CaseBB == CurMBB)
visitSwitchCase(CB);
else
SwitchCases.push_back(CB);
return true;
}
/// handleBitTestsSwitchCase - if current case range has few destination and
/// range span less, than machine word bitwidth, encode case range into series
/// of masks and emit bit tests with these masks.
bool SelectionDAGLowering::handleBitTestsSwitchCase(CaseRec& CR,
CaseRecVector& WorkList,
Value* SV,
MachineBasicBlock* Default){
unsigned IntPtrBits = TLI.getPointerTy().getSizeInBits();
Case& FrontCase = *CR.Range.first;
Case& BackCase = *(CR.Range.second-1);
// Get the MachineFunction which holds the current MBB. This is used when
// inserting any additional MBBs necessary to represent the switch.
MachineFunction *CurMF = CurMBB->getParent();
// If target does not have legal shift left, do not emit bit tests at all.
if (!TLI.isOperationLegal(ISD::SHL, TLI.getPointerTy()))
return false;
size_t numCmps = 0;
for (CaseItr I = CR.Range.first, E = CR.Range.second;
I!=E; ++I) {
// Single case counts one, case range - two.
numCmps += (I->Low == I->High ? 1 : 2);
}
// Count unique destinations
SmallSet<MachineBasicBlock*, 4> Dests;
for (CaseItr I = CR.Range.first, E = CR.Range.second; I!=E; ++I) {
Dests.insert(I->BB);
if (Dests.size() > 3)
// Don't bother the code below, if there are too much unique destinations
return false;
}
DEBUG(errs() << "Total number of unique destinations: " << Dests.size() << '\n'
<< "Total number of comparisons: " << numCmps << '\n');
// Compute span of values.
const APInt& minValue = cast<ConstantInt>(FrontCase.Low)->getValue();
const APInt& maxValue = cast<ConstantInt>(BackCase.High)->getValue();
APInt cmpRange = maxValue - minValue;
DEBUG(errs() << "Compare range: " << cmpRange << '\n'
<< "Low bound: " << minValue << '\n'
<< "High bound: " << maxValue << '\n');
if (cmpRange.uge(APInt(cmpRange.getBitWidth(), IntPtrBits)) ||
(!(Dests.size() == 1 && numCmps >= 3) &&
!(Dests.size() == 2 && numCmps >= 5) &&
!(Dests.size() >= 3 && numCmps >= 6)))
return false;
DEBUG(errs() << "Emitting bit tests\n");
APInt lowBound = APInt::getNullValue(cmpRange.getBitWidth());
// Optimize the case where all the case values fit in a
// word without having to subtract minValue. In this case,
// we can optimize away the subtraction.
if (minValue.isNonNegative() &&
maxValue.slt(APInt(maxValue.getBitWidth(), IntPtrBits))) {
cmpRange = maxValue;
} else {
lowBound = minValue;
}
CaseBitsVector CasesBits;
unsigned i, count = 0;
for (CaseItr I = CR.Range.first, E = CR.Range.second; I!=E; ++I) {
MachineBasicBlock* Dest = I->BB;
for (i = 0; i < count; ++i)
if (Dest == CasesBits[i].BB)
break;
if (i == count) {
assert((count < 3) && "Too much destinations to test!");
CasesBits.push_back(CaseBits(0, Dest, 0));
count++;
}
const APInt& lowValue = cast<ConstantInt>(I->Low)->getValue();
const APInt& highValue = cast<ConstantInt>(I->High)->getValue();
uint64_t lo = (lowValue - lowBound).getZExtValue();
uint64_t hi = (highValue - lowBound).getZExtValue();
for (uint64_t j = lo; j <= hi; j++) {
CasesBits[i].Mask |= 1ULL << j;
CasesBits[i].Bits++;
}
}
std::sort(CasesBits.begin(), CasesBits.end(), CaseBitsCmp());
BitTestInfo BTC;
// Figure out which block is immediately after the current one.
MachineFunction::iterator BBI = CR.CaseBB;
++BBI;
const BasicBlock *LLVMBB = CR.CaseBB->getBasicBlock();
DEBUG(errs() << "Cases:\n");
for (unsigned i = 0, e = CasesBits.size(); i!=e; ++i) {
DEBUG(errs() << "Mask: " << CasesBits[i].Mask
<< ", Bits: " << CasesBits[i].Bits
<< ", BB: " << CasesBits[i].BB << '\n');
MachineBasicBlock *CaseBB = CurMF->CreateMachineBasicBlock(LLVMBB);
CurMF->insert(BBI, CaseBB);
BTC.push_back(BitTestCase(CasesBits[i].Mask,
CaseBB,
CasesBits[i].BB));
// Put SV in a virtual register to make it available from the new blocks.
ExportFromCurrentBlock(SV);
}
BitTestBlock BTB(lowBound, cmpRange, SV,
-1U, (CR.CaseBB == CurMBB),
CR.CaseBB, Default, BTC);
if (CR.CaseBB == CurMBB)
visitBitTestHeader(BTB);
BitTestCases.push_back(BTB);
return true;
}
/// Clusterify - Transform simple list of Cases into list of CaseRange's
size_t SelectionDAGLowering::Clusterify(CaseVector& Cases,
const SwitchInst& SI) {
size_t numCmps = 0;
// Start with "simple" cases
for (size_t i = 1; i < SI.getNumSuccessors(); ++i) {
MachineBasicBlock *SMBB = FuncInfo.MBBMap[SI.getSuccessor(i)];
Cases.push_back(Case(SI.getSuccessorValue(i),
SI.getSuccessorValue(i),
SMBB));
}
std::sort(Cases.begin(), Cases.end(), CaseCmp());
// Merge case into clusters
if (Cases.size() >= 2)
// Must recompute end() each iteration because it may be
// invalidated by erase if we hold on to it
for (CaseItr I = Cases.begin(), J = ++(Cases.begin()); J != Cases.end(); ) {
const APInt& nextValue = cast<ConstantInt>(J->Low)->getValue();
const APInt& currentValue = cast<ConstantInt>(I->High)->getValue();
MachineBasicBlock* nextBB = J->BB;
MachineBasicBlock* currentBB = I->BB;
// If the two neighboring cases go to the same destination, merge them
// into a single case.
if ((nextValue - currentValue == 1) && (currentBB == nextBB)) {
I->High = J->High;
J = Cases.erase(J);
} else {
I = J++;
}
}
for (CaseItr I=Cases.begin(), E=Cases.end(); I!=E; ++I, ++numCmps) {
if (I->Low != I->High)
// A range counts double, since it requires two compares.
++numCmps;
}
return numCmps;
}
void SelectionDAGLowering::visitSwitch(SwitchInst &SI) {
// Figure out which block is immediately after the current one.
MachineBasicBlock *NextBlock = 0;
MachineFunction::iterator BBI = CurMBB;
MachineBasicBlock *Default = FuncInfo.MBBMap[SI.getDefaultDest()];
// If there is only the default destination, branch to it if it is not the
// next basic block. Otherwise, just fall through.
if (SI.getNumOperands() == 2) {
// Update machine-CFG edges.
// If this is not a fall-through branch, emit the branch.
CurMBB->addSuccessor(Default);
if (Default != NextBlock)
DAG.setRoot(DAG.getNode(ISD::BR, getCurDebugLoc(),
MVT::Other, getControlRoot(),
DAG.getBasicBlock(Default)));
return;
}
// If there are any non-default case statements, create a vector of Cases
// representing each one, and sort the vector so that we can efficiently
// create a binary search tree from them.
CaseVector Cases;
size_t numCmps = Clusterify(Cases, SI);
DEBUG(errs() << "Clusterify finished. Total clusters: " << Cases.size()
<< ". Total compares: " << numCmps << '\n');
numCmps = 0;
// Get the Value to be switched on and default basic blocks, which will be
// inserted into CaseBlock records, representing basic blocks in the binary
// search tree.
Value *SV = SI.getOperand(0);
// Push the initial CaseRec onto the worklist
CaseRecVector WorkList;
WorkList.push_back(CaseRec(CurMBB,0,0,CaseRange(Cases.begin(),Cases.end())));
while (!WorkList.empty()) {
// Grab a record representing a case range to process off the worklist
CaseRec CR = WorkList.back();
WorkList.pop_back();
if (handleBitTestsSwitchCase(CR, WorkList, SV, Default))
continue;
// If the range has few cases (two or less) emit a series of specific
// tests.
if (handleSmallSwitchRange(CR, WorkList, SV, Default))
continue;
// If the switch has more than 5 blocks, and at least 40% dense, and the
// target supports indirect branches, then emit a jump table rather than
// lowering the switch to a binary tree of conditional branches.
if (handleJTSwitchCase(CR, WorkList, SV, Default))
continue;
// Emit binary tree. We need to pick a pivot, and push left and right ranges
// onto the worklist. Leafs are handled via handleSmallSwitchRange() call.
handleBTSplitSwitchCase(CR, WorkList, SV, Default);
}
}
void SelectionDAGLowering::visitSub(User &I) {
// -0.0 - X --> fneg
const Type *Ty = I.getType();
if (isa<VectorType>(Ty)) {
if (ConstantVector *CV = dyn_cast<ConstantVector>(I.getOperand(0))) {
const VectorType *DestTy = cast<VectorType>(I.getType());
const Type *ElTy = DestTy->getElementType();
if (ElTy->isFloatingPoint()) {
unsigned VL = DestTy->getNumElements();
std::vector<Constant*> NZ(VL, ConstantFP::getNegativeZero(ElTy));
Constant *CNZ = ConstantVector::get(&NZ[0], NZ.size());
if (CV == CNZ) {
SDValue Op2 = getValue(I.getOperand(1));
setValue(&I, DAG.getNode(ISD::FNEG, getCurDebugLoc(),
Op2.getValueType(), Op2));
return;
}
}
}
}
if (Ty->isFloatingPoint()) {
if (ConstantFP *CFP = dyn_cast<ConstantFP>(I.getOperand(0)))
if (CFP->isExactlyValue(ConstantFP::getNegativeZero(Ty)->getValueAPF())) {
SDValue Op2 = getValue(I.getOperand(1));
setValue(&I, DAG.getNode(ISD::FNEG, getCurDebugLoc(),
Op2.getValueType(), Op2));
return;
}
}
visitBinary(I, Ty->isFPOrFPVector() ? ISD::FSUB : ISD::SUB);
}
void SelectionDAGLowering::visitBinary(User &I, unsigned OpCode) {
SDValue Op1 = getValue(I.getOperand(0));
SDValue Op2 = getValue(I.getOperand(1));
setValue(&I, DAG.getNode(OpCode, getCurDebugLoc(),
Op1.getValueType(), Op1, Op2));
}
void SelectionDAGLowering::visitShift(User &I, unsigned Opcode) {
SDValue Op1 = getValue(I.getOperand(0));
SDValue Op2 = getValue(I.getOperand(1));
if (!isa<VectorType>(I.getType()) &&
Op2.getValueType() != TLI.getShiftAmountTy()) {
// If the operand is smaller than the shift count type, promote it.
if (TLI.getShiftAmountTy().bitsGT(Op2.getValueType()))
Op2 = DAG.getNode(ISD::ANY_EXTEND, getCurDebugLoc(),
TLI.getShiftAmountTy(), Op2);
// If the operand is larger than the shift count type but the shift
// count type has enough bits to represent any shift value, truncate
// it now. This is a common case and it exposes the truncate to
// optimization early.
else if (TLI.getShiftAmountTy().getSizeInBits() >=
Log2_32_Ceil(Op2.getValueType().getSizeInBits()))
Op2 = DAG.getNode(ISD::TRUNCATE, getCurDebugLoc(),
TLI.getShiftAmountTy(), Op2);
// Otherwise we'll need to temporarily settle for some other
// convenient type; type legalization will make adjustments as
// needed.
else if (TLI.getPointerTy().bitsLT(Op2.getValueType()))
Op2 = DAG.getNode(ISD::TRUNCATE, getCurDebugLoc(),
TLI.getPointerTy(), Op2);
else if (TLI.getPointerTy().bitsGT(Op2.getValueType()))
Op2 = DAG.getNode(ISD::ANY_EXTEND, getCurDebugLoc(),
TLI.getPointerTy(), Op2);
}
setValue(&I, DAG.getNode(Opcode, getCurDebugLoc(),
Op1.getValueType(), Op1, Op2));
}
void SelectionDAGLowering::visitICmp(User &I) {
ICmpInst::Predicate predicate = ICmpInst::BAD_ICMP_PREDICATE;
if (ICmpInst *IC = dyn_cast<ICmpInst>(&I))
predicate = IC->getPredicate();
else if (ConstantExpr *IC = dyn_cast<ConstantExpr>(&I))
predicate = ICmpInst::Predicate(IC->getPredicate());
SDValue Op1 = getValue(I.getOperand(0));
SDValue Op2 = getValue(I.getOperand(1));
ISD::CondCode Opcode = getICmpCondCode(predicate);
setValue(&I, DAG.getSetCC(getCurDebugLoc(),MVT::i1, Op1, Op2, Opcode));
}
void SelectionDAGLowering::visitFCmp(User &I) {
FCmpInst::Predicate predicate = FCmpInst::BAD_FCMP_PREDICATE;
if (FCmpInst *FC = dyn_cast<FCmpInst>(&I))
predicate = FC->getPredicate();
else if (ConstantExpr *FC = dyn_cast<ConstantExpr>(&I))
predicate = FCmpInst::Predicate(FC->getPredicate());
SDValue Op1 = getValue(I.getOperand(0));
SDValue Op2 = getValue(I.getOperand(1));
ISD::CondCode Condition = getFCmpCondCode(predicate);
setValue(&I, DAG.getSetCC(getCurDebugLoc(), MVT::i1, Op1, Op2, Condition));
}
void SelectionDAGLowering::visitVICmp(User &I) {
ICmpInst::Predicate predicate = ICmpInst::BAD_ICMP_PREDICATE;
if (VICmpInst *IC = dyn_cast<VICmpInst>(&I))
predicate = IC->getPredicate();
else if (ConstantExpr *IC = dyn_cast<ConstantExpr>(&I))
predicate = ICmpInst::Predicate(IC->getPredicate());
SDValue Op1 = getValue(I.getOperand(0));
SDValue Op2 = getValue(I.getOperand(1));
ISD::CondCode Opcode = getICmpCondCode(predicate);
setValue(&I, DAG.getVSetCC(getCurDebugLoc(), Op1.getValueType(),
Op1, Op2, Opcode));
}
void SelectionDAGLowering::visitVFCmp(User &I) {
FCmpInst::Predicate predicate = FCmpInst::BAD_FCMP_PREDICATE;
if (VFCmpInst *FC = dyn_cast<VFCmpInst>(&I))
predicate = FC->getPredicate();
else if (ConstantExpr *FC = dyn_cast<ConstantExpr>(&I))
predicate = FCmpInst::Predicate(FC->getPredicate());
SDValue Op1 = getValue(I.getOperand(0));
SDValue Op2 = getValue(I.getOperand(1));
ISD::CondCode Condition = getFCmpCondCode(predicate);
MVT DestVT = TLI.getValueType(I.getType());
setValue(&I, DAG.getVSetCC(getCurDebugLoc(), DestVT, Op1, Op2, Condition));
}
void SelectionDAGLowering::visitSelect(User &I) {
SmallVector<MVT, 4> ValueVTs;
ComputeValueVTs(TLI, I.getType(), ValueVTs);
unsigned NumValues = ValueVTs.size();
if (NumValues != 0) {
SmallVector<SDValue, 4> Values(NumValues);
SDValue Cond = getValue(I.getOperand(0));
SDValue TrueVal = getValue(I.getOperand(1));
SDValue FalseVal = getValue(I.getOperand(2));
for (unsigned i = 0; i != NumValues; ++i)
Values[i] = DAG.getNode(ISD::SELECT, getCurDebugLoc(),
TrueVal.getValueType(), Cond,
SDValue(TrueVal.getNode(), TrueVal.getResNo() + i),
SDValue(FalseVal.getNode(), FalseVal.getResNo() + i));
setValue(&I, DAG.getNode(ISD::MERGE_VALUES, getCurDebugLoc(),
DAG.getVTList(&ValueVTs[0], NumValues),
&Values[0], NumValues));
}
}
void SelectionDAGLowering::visitTrunc(User &I) {
// TruncInst cannot be a no-op cast because sizeof(src) > sizeof(dest).
SDValue N = getValue(I.getOperand(0));
MVT DestVT = TLI.getValueType(I.getType());
setValue(&I, DAG.getNode(ISD::TRUNCATE, getCurDebugLoc(), DestVT, N));
}
void SelectionDAGLowering::visitZExt(User &I) {
// ZExt cannot be a no-op cast because sizeof(src) < sizeof(dest).
// ZExt also can't be a cast to bool for same reason. So, nothing much to do
SDValue N = getValue(I.getOperand(0));
MVT DestVT = TLI.getValueType(I.getType());
setValue(&I, DAG.getNode(ISD::ZERO_EXTEND, getCurDebugLoc(), DestVT, N));
}
void SelectionDAGLowering::visitSExt(User &I) {
// SExt cannot be a no-op cast because sizeof(src) < sizeof(dest).
// SExt also can't be a cast to bool for same reason. So, nothing much to do
SDValue N = getValue(I.getOperand(0));
MVT DestVT = TLI.getValueType(I.getType());
setValue(&I, DAG.getNode(ISD::SIGN_EXTEND, getCurDebugLoc(), DestVT, N));
}
void SelectionDAGLowering::visitFPTrunc(User &I) {
// FPTrunc is never a no-op cast, no need to check
SDValue N = getValue(I.getOperand(0));
MVT DestVT = TLI.getValueType(I.getType());
setValue(&I, DAG.getNode(ISD::FP_ROUND, getCurDebugLoc(),
DestVT, N, DAG.getIntPtrConstant(0)));
}
void SelectionDAGLowering::visitFPExt(User &I){
// FPTrunc is never a no-op cast, no need to check
SDValue N = getValue(I.getOperand(0));
MVT DestVT = TLI.getValueType(I.getType());
setValue(&I, DAG.getNode(ISD::FP_EXTEND, getCurDebugLoc(), DestVT, N));
}
void SelectionDAGLowering::visitFPToUI(User &I) {
// FPToUI is never a no-op cast, no need to check
SDValue N = getValue(I.getOperand(0));
MVT DestVT = TLI.getValueType(I.getType());
setValue(&I, DAG.getNode(ISD::FP_TO_UINT, getCurDebugLoc(), DestVT, N));
}
void SelectionDAGLowering::visitFPToSI(User &I) {
// FPToSI is never a no-op cast, no need to check
SDValue N = getValue(I.getOperand(0));
MVT DestVT = TLI.getValueType(I.getType());
setValue(&I, DAG.getNode(ISD::FP_TO_SINT, getCurDebugLoc(), DestVT, N));
}
void SelectionDAGLowering::visitUIToFP(User &I) {
// UIToFP is never a no-op cast, no need to check
SDValue N = getValue(I.getOperand(0));
MVT DestVT = TLI.getValueType(I.getType());
setValue(&I, DAG.getNode(ISD::UINT_TO_FP, getCurDebugLoc(), DestVT, N));
}
void SelectionDAGLowering::visitSIToFP(User &I){
// SIToFP is never a no-op cast, no need to check
SDValue N = getValue(I.getOperand(0));
MVT DestVT = TLI.getValueType(I.getType());
setValue(&I, DAG.getNode(ISD::SINT_TO_FP, getCurDebugLoc(), DestVT, N));
}
void SelectionDAGLowering::visitPtrToInt(User &I) {
// What to do depends on the size of the integer and the size of the pointer.
// We can either truncate, zero extend, or no-op, accordingly.
SDValue N = getValue(I.getOperand(0));
MVT SrcVT = N.getValueType();
MVT DestVT = TLI.getValueType(I.getType());
SDValue Result;
if (DestVT.bitsLT(SrcVT))
Result = DAG.getNode(ISD::TRUNCATE, getCurDebugLoc(), DestVT, N);
else
// Note: ZERO_EXTEND can handle cases where the sizes are equal too
Result = DAG.getNode(ISD::ZERO_EXTEND, getCurDebugLoc(), DestVT, N);
setValue(&I, Result);
}
void SelectionDAGLowering::visitIntToPtr(User &I) {
// What to do depends on the size of the integer and the size of the pointer.
// We can either truncate, zero extend, or no-op, accordingly.
SDValue N = getValue(I.getOperand(0));
MVT SrcVT = N.getValueType();
MVT DestVT = TLI.getValueType(I.getType());
if (DestVT.bitsLT(SrcVT))
setValue(&I, DAG.getNode(ISD::TRUNCATE, getCurDebugLoc(), DestVT, N));
else
// Note: ZERO_EXTEND can handle cases where the sizes are equal too
setValue(&I, DAG.getNode(ISD::ZERO_EXTEND, getCurDebugLoc(),
DestVT, N));
}
void SelectionDAGLowering::visitBitCast(User &I) {
SDValue N = getValue(I.getOperand(0));
MVT DestVT = TLI.getValueType(I.getType());
// BitCast assures us that source and destination are the same size so this
// is either a BIT_CONVERT or a no-op.
if (DestVT != N.getValueType())
setValue(&I, DAG.getNode(ISD::BIT_CONVERT, getCurDebugLoc(),
DestVT, N)); // convert types
else
setValue(&I, N); // noop cast.
}
void SelectionDAGLowering::visitInsertElement(User &I) {
SDValue InVec = getValue(I.getOperand(0));
SDValue InVal = getValue(I.getOperand(1));
SDValue InIdx = DAG.getNode(ISD::ZERO_EXTEND, getCurDebugLoc(),
TLI.getPointerTy(),
getValue(I.getOperand(2)));
setValue(&I, DAG.getNode(ISD::INSERT_VECTOR_ELT, getCurDebugLoc(),
TLI.getValueType(I.getType()),
InVec, InVal, InIdx));
}
void SelectionDAGLowering::visitExtractElement(User &I) {
SDValue InVec = getValue(I.getOperand(0));
SDValue InIdx = DAG.getNode(ISD::ZERO_EXTEND, getCurDebugLoc(),
TLI.getPointerTy(),
getValue(I.getOperand(1)));
setValue(&I, DAG.getNode(ISD::EXTRACT_VECTOR_ELT, getCurDebugLoc(),
TLI.getValueType(I.getType()), InVec, InIdx));
}
// Utility for visitShuffleVector - Returns true if the mask is mask starting
// from SIndx and increasing to the element length (undefs are allowed).
static bool SequentialMask(SmallVectorImpl<int> &Mask, unsigned SIndx) {
unsigned MaskNumElts = Mask.size();
for (unsigned i = 0; i != MaskNumElts; ++i)
if ((Mask[i] >= 0) && (Mask[i] != (int)(i + SIndx)))
return false;
return true;
}
void SelectionDAGLowering::visitShuffleVector(User &I) {
SmallVector<int, 8> Mask;
SDValue Src1 = getValue(I.getOperand(0));
SDValue Src2 = getValue(I.getOperand(1));
// Convert the ConstantVector mask operand into an array of ints, with -1
// representing undef values.
SmallVector<Constant*, 8> MaskElts;
cast<Constant>(I.getOperand(2))->getVectorElements(MaskElts);
unsigned MaskNumElts = MaskElts.size();
for (unsigned i = 0; i != MaskNumElts; ++i) {
if (isa<UndefValue>(MaskElts[i]))
Mask.push_back(-1);
else
Mask.push_back(cast<ConstantInt>(MaskElts[i])->getSExtValue());
}
MVT VT = TLI.getValueType(I.getType());
MVT SrcVT = Src1.getValueType();
unsigned SrcNumElts = SrcVT.getVectorNumElements();
if (SrcNumElts == MaskNumElts) {
setValue(&I, DAG.getVectorShuffle(VT, getCurDebugLoc(), Src1, Src2,
&Mask[0]));
return;
}
// Normalize the shuffle vector since mask and vector length don't match.
if (SrcNumElts < MaskNumElts && MaskNumElts % SrcNumElts == 0) {
// Mask is longer than the source vectors and is a multiple of the source
// vectors. We can use concatenate vector to make the mask and vectors
// lengths match.
if (SrcNumElts*2 == MaskNumElts && SequentialMask(Mask, 0)) {
// The shuffle is concatenating two vectors together.
setValue(&I, DAG.getNode(ISD::CONCAT_VECTORS, getCurDebugLoc(),
VT, Src1, Src2));
return;
}
// Pad both vectors with undefs to make them the same length as the mask.
unsigned NumConcat = MaskNumElts / SrcNumElts;
bool Src1U = Src1.getOpcode() == ISD::UNDEF;
bool Src2U = Src2.getOpcode() == ISD::UNDEF;
SDValue UndefVal = DAG.getUNDEF(SrcVT);
SmallVector<SDValue, 8> MOps1(NumConcat, UndefVal);
SmallVector<SDValue, 8> MOps2(NumConcat, UndefVal);
MOps1[0] = Src1;
MOps2[0] = Src2;
Src1 = Src1U ? DAG.getUNDEF(VT) : DAG.getNode(ISD::CONCAT_VECTORS,
getCurDebugLoc(), VT,
&MOps1[0], NumConcat);
Src2 = Src2U ? DAG.getUNDEF(VT) : DAG.getNode(ISD::CONCAT_VECTORS,
getCurDebugLoc(), VT,
&MOps2[0], NumConcat);
// Readjust mask for new input vector length.
SmallVector<int, 8> MappedOps;
for (unsigned i = 0; i != MaskNumElts; ++i) {
int Idx = Mask[i];
if (Idx < (int)SrcNumElts)
MappedOps.push_back(Idx);
else
MappedOps.push_back(Idx + MaskNumElts - SrcNumElts);
}
setValue(&I, DAG.getVectorShuffle(VT, getCurDebugLoc(), Src1, Src2,
&MappedOps[0]));
return;
}
if (SrcNumElts > MaskNumElts) {
// Analyze the access pattern of the vector to see if we can extract
// two subvectors and do the shuffle. The analysis is done by calculating
// the range of elements the mask access on both vectors.
int MinRange[2] = { SrcNumElts+1, SrcNumElts+1};
int MaxRange[2] = {-1, -1};
for (unsigned i = 0; i != MaskNumElts; ++i) {
int Idx = Mask[i];
int Input = 0;
if (Idx < 0)
continue;
if (Idx >= (int)SrcNumElts) {
Input = 1;
Idx -= SrcNumElts;
}
if (Idx > MaxRange[Input])
MaxRange[Input] = Idx;
if (Idx < MinRange[Input])
MinRange[Input] = Idx;
}
// Check if the access is smaller than the vector size and can we find
// a reasonable extract index.
int RangeUse[2] = { 2, 2 }; // 0 = Unused, 1 = Extract, 2 = Can not Extract.
int StartIdx[2]; // StartIdx to extract from
for (int Input=0; Input < 2; ++Input) {
if (MinRange[Input] == (int)(SrcNumElts+1) && MaxRange[Input] == -1) {
RangeUse[Input] = 0; // Unused
StartIdx[Input] = 0;
} else if (MaxRange[Input] - MinRange[Input] < (int)MaskNumElts) {
// Fits within range but we should see if we can find a good
// start index that is a multiple of the mask length.
if (MaxRange[Input] < (int)MaskNumElts) {
RangeUse[Input] = 1; // Extract from beginning of the vector
StartIdx[Input] = 0;
} else {
StartIdx[Input] = (MinRange[Input]/MaskNumElts)*MaskNumElts;
if (MaxRange[Input] - StartIdx[Input] < (int)MaskNumElts &&
StartIdx[Input] + MaskNumElts < SrcNumElts)
RangeUse[Input] = 1; // Extract from a multiple of the mask length.
}
}
}
if (RangeUse[0] == 0 && RangeUse[0] == 0) {
setValue(&I, DAG.getUNDEF(VT)); // Vectors are not used.
return;
}
else if (RangeUse[0] < 2 && RangeUse[1] < 2) {
// Extract appropriate subvector and generate a vector shuffle
for (int Input=0; Input < 2; ++Input) {
SDValue& Src = Input == 0 ? Src1 : Src2;
if (RangeUse[Input] == 0) {
Src = DAG.getUNDEF(VT);
} else {
Src = DAG.getNode(ISD::EXTRACT_SUBVECTOR, getCurDebugLoc(), VT,
Src, DAG.getIntPtrConstant(StartIdx[Input]));
}
}
// Calculate new mask.
SmallVector<int, 8> MappedOps;
for (unsigned i = 0; i != MaskNumElts; ++i) {
int Idx = Mask[i];
if (Idx < 0)
MappedOps.push_back(Idx);
else if (Idx < (int)SrcNumElts)
MappedOps.push_back(Idx - StartIdx[0]);
else
MappedOps.push_back(Idx - SrcNumElts - StartIdx[1] + MaskNumElts);
}
setValue(&I, DAG.getVectorShuffle(VT, getCurDebugLoc(), Src1, Src2,
&MappedOps[0]));
return;
}
}
// We can't use either concat vectors or extract subvectors so fall back to
// replacing the shuffle with extract and build vector.
// to insert and build vector.
MVT EltVT = VT.getVectorElementType();
MVT PtrVT = TLI.getPointerTy();
SmallVector<SDValue,8> Ops;
for (unsigned i = 0; i != MaskNumElts; ++i) {
if (Mask[i] < 0) {
Ops.push_back(DAG.getUNDEF(EltVT));
} else {
int Idx = Mask[i];
if (Idx < (int)SrcNumElts)
Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, getCurDebugLoc(),
EltVT, Src1, DAG.getConstant(Idx, PtrVT)));
else
Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, getCurDebugLoc(),
EltVT, Src2,
DAG.getConstant(Idx - SrcNumElts, PtrVT)));
}
}
setValue(&I, DAG.getNode(ISD::BUILD_VECTOR, getCurDebugLoc(),
VT, &Ops[0], Ops.size()));
}
void SelectionDAGLowering::visitInsertValue(InsertValueInst &I) {
const Value *Op0 = I.getOperand(0);
const Value *Op1 = I.getOperand(1);
const Type *AggTy = I.getType();
const Type *ValTy = Op1->getType();
bool IntoUndef = isa<UndefValue>(Op0);
bool FromUndef = isa<UndefValue>(Op1);
unsigned LinearIndex = ComputeLinearIndex(TLI, AggTy,
I.idx_begin(), I.idx_end());
SmallVector<MVT, 4> AggValueVTs;
ComputeValueVTs(TLI, AggTy, AggValueVTs);
SmallVector<MVT, 4> ValValueVTs;
ComputeValueVTs(TLI, ValTy, ValValueVTs);
unsigned NumAggValues = AggValueVTs.size();
unsigned NumValValues = ValValueVTs.size();
SmallVector<SDValue, 4> Values(NumAggValues);
SDValue Agg = getValue(Op0);
SDValue Val = getValue(Op1);
unsigned i = 0;
// Copy the beginning value(s) from the original aggregate.
for (; i != LinearIndex; ++i)
Values[i] = IntoUndef ? DAG.getUNDEF(AggValueVTs[i]) :
SDValue(Agg.getNode(), Agg.getResNo() + i);
// Copy values from the inserted value(s).
for (; i != LinearIndex + NumValValues; ++i)
Values[i] = FromUndef ? DAG.getUNDEF(AggValueVTs[i]) :
SDValue(Val.getNode(), Val.getResNo() + i - LinearIndex);
// Copy remaining value(s) from the original aggregate.
for (; i != NumAggValues; ++i)
Values[i] = IntoUndef ? DAG.getUNDEF(AggValueVTs[i]) :
SDValue(Agg.getNode(), Agg.getResNo() + i);
setValue(&I, DAG.getNode(ISD::MERGE_VALUES, getCurDebugLoc(),
DAG.getVTList(&AggValueVTs[0], NumAggValues),
&Values[0], NumAggValues));
}
void SelectionDAGLowering::visitExtractValue(ExtractValueInst &I) {
const Value *Op0 = I.getOperand(0);
const Type *AggTy = Op0->getType();
const Type *ValTy = I.getType();
bool OutOfUndef = isa<UndefValue>(Op0);
unsigned LinearIndex = ComputeLinearIndex(TLI, AggTy,
I.idx_begin(), I.idx_end());
SmallVector<MVT, 4> ValValueVTs;
ComputeValueVTs(TLI, ValTy, ValValueVTs);
unsigned NumValValues = ValValueVTs.size();
SmallVector<SDValue, 4> Values(NumValValues);
SDValue Agg = getValue(Op0);
// Copy out the selected value(s).
for (unsigned i = LinearIndex; i != LinearIndex + NumValValues; ++i)
Values[i - LinearIndex] =
OutOfUndef ?
DAG.getUNDEF(Agg.getNode()->getValueType(Agg.getResNo() + i)) :
SDValue(Agg.getNode(), Agg.getResNo() + i);
setValue(&I, DAG.getNode(ISD::MERGE_VALUES, getCurDebugLoc(),
DAG.getVTList(&ValValueVTs[0], NumValValues),
&Values[0], NumValValues));
}
void SelectionDAGLowering::visitGetElementPtr(User &I) {
SDValue N = getValue(I.getOperand(0));
const Type *Ty = I.getOperand(0)->getType();
for (GetElementPtrInst::op_iterator OI = I.op_begin()+1, E = I.op_end();
OI != E; ++OI) {
Value *Idx = *OI;
if (const StructType *StTy = dyn_cast<StructType>(Ty)) {
unsigned Field = cast<ConstantInt>(Idx)->getZExtValue();
if (Field) {
// N = N + Offset
uint64_t Offset = TD->getStructLayout(StTy)->getElementOffset(Field);
N = DAG.getNode(ISD::ADD, getCurDebugLoc(), N.getValueType(), N,
DAG.getIntPtrConstant(Offset));
}
Ty = StTy->getElementType(Field);
} else {
Ty = cast<SequentialType>(Ty)->getElementType();
// If this is a constant subscript, handle it quickly.
if (ConstantInt *CI = dyn_cast<ConstantInt>(Idx)) {
if (CI->getZExtValue() == 0) continue;
uint64_t Offs =
TD->getTypeAllocSize(Ty)*cast<ConstantInt>(CI)->getSExtValue();
SDValue OffsVal;
unsigned PtrBits = TLI.getPointerTy().getSizeInBits();
if (PtrBits < 64) {
OffsVal = DAG.getNode(ISD::TRUNCATE, getCurDebugLoc(),
TLI.getPointerTy(),
DAG.getConstant(Offs, MVT::i64));
} else
OffsVal = DAG.getIntPtrConstant(Offs);
N = DAG.getNode(ISD::ADD, getCurDebugLoc(), N.getValueType(), N,
OffsVal);
continue;
}
// N = N + Idx * ElementSize;
uint64_t ElementSize = TD->getTypeAllocSize(Ty);
SDValue IdxN = getValue(Idx);
// If the index is smaller or larger than intptr_t, truncate or extend
// it.
if (IdxN.getValueType().bitsLT(N.getValueType()))
IdxN = DAG.getNode(ISD::SIGN_EXTEND, getCurDebugLoc(),
N.getValueType(), IdxN);
else if (IdxN.getValueType().bitsGT(N.getValueType()))
IdxN = DAG.getNode(ISD::TRUNCATE, getCurDebugLoc(),
N.getValueType(), IdxN);
// If this is a multiply by a power of two, turn it into a shl
// immediately. This is a very common case.
if (ElementSize != 1) {
if (isPowerOf2_64(ElementSize)) {
unsigned Amt = Log2_64(ElementSize);
IdxN = DAG.getNode(ISD::SHL, getCurDebugLoc(),
N.getValueType(), IdxN,
DAG.getConstant(Amt, TLI.getPointerTy()));
} else {
SDValue Scale = DAG.getIntPtrConstant(ElementSize);
IdxN = DAG.getNode(ISD::MUL, getCurDebugLoc(),
N.getValueType(), IdxN, Scale);
}
}
N = DAG.getNode(ISD::ADD, getCurDebugLoc(),
N.getValueType(), N, IdxN);
}
}
setValue(&I, N);
}
void SelectionDAGLowering::visitAlloca(AllocaInst &I) {
// If this is a fixed sized alloca in the entry block of the function,
// allocate it statically on the stack.
if (FuncInfo.StaticAllocaMap.count(&I))
return; // getValue will auto-populate this.
const Type *Ty = I.getAllocatedType();
uint64_t TySize = TLI.getTargetData()->getTypeAllocSize(Ty);
unsigned Align =
std::max((unsigned)TLI.getTargetData()->getPrefTypeAlignment(Ty),
I.getAlignment());
SDValue AllocSize = getValue(I.getArraySize());
AllocSize = DAG.getNode(ISD::MUL, getCurDebugLoc(), AllocSize.getValueType(),
AllocSize,
DAG.getConstant(TySize, AllocSize.getValueType()));
MVT IntPtr = TLI.getPointerTy();
if (IntPtr.bitsLT(AllocSize.getValueType()))
AllocSize = DAG.getNode(ISD::TRUNCATE, getCurDebugLoc(),
IntPtr, AllocSize);
else if (IntPtr.bitsGT(AllocSize.getValueType()))
AllocSize = DAG.getNode(ISD::ZERO_EXTEND, getCurDebugLoc(),
IntPtr, AllocSize);
// Handle alignment. If the requested alignment is less than or equal to
// the stack alignment, ignore it. If the size is greater than or equal to
// the stack alignment, we note this in the DYNAMIC_STACKALLOC node.
unsigned StackAlign =
TLI.getTargetMachine().getFrameInfo()->getStackAlignment();
if (Align <= StackAlign)
Align = 0;
// Round the size of the allocation up to the stack alignment size
// by add SA-1 to the size.
AllocSize = DAG.getNode(ISD::ADD, getCurDebugLoc(),
AllocSize.getValueType(), AllocSize,
DAG.getIntPtrConstant(StackAlign-1));
// Mask out the low bits for alignment purposes.
AllocSize = DAG.getNode(ISD::AND, getCurDebugLoc(),
AllocSize.getValueType(), AllocSize,
DAG.getIntPtrConstant(~(uint64_t)(StackAlign-1)));
SDValue Ops[] = { getRoot(), AllocSize, DAG.getIntPtrConstant(Align) };
SDVTList VTs = DAG.getVTList(AllocSize.getValueType(), MVT::Other);
SDValue DSA = DAG.getNode(ISD::DYNAMIC_STACKALLOC, getCurDebugLoc(),
VTs, Ops, 3);
setValue(&I, DSA);
DAG.setRoot(DSA.getValue(1));
// Inform the Frame Information that we have just allocated a variable-sized
// object.
CurMBB->getParent()->getFrameInfo()->CreateVariableSizedObject();
}
void SelectionDAGLowering::visitLoad(LoadInst &I) {
const Value *SV = I.getOperand(0);
SDValue Ptr = getValue(SV);
const Type *Ty = I.getType();
bool isVolatile = I.isVolatile();
unsigned Alignment = I.getAlignment();
SmallVector<MVT, 4> ValueVTs;
SmallVector<uint64_t, 4> Offsets;
ComputeValueVTs(TLI, Ty, ValueVTs, &Offsets);
unsigned NumValues = ValueVTs.size();
if (NumValues == 0)
return;
SDValue Root;
bool ConstantMemory = false;
if (I.isVolatile())
// Serialize volatile loads with other side effects.
Root = getRoot();
else if (AA->pointsToConstantMemory(SV)) {
// Do not serialize (non-volatile) loads of constant memory with anything.
Root = DAG.getEntryNode();
ConstantMemory = true;
} else {
// Do not serialize non-volatile loads against each other.
Root = DAG.getRoot();
}
SmallVector<SDValue, 4> Values(NumValues);
SmallVector<SDValue, 4> Chains(NumValues);
MVT PtrVT = Ptr.getValueType();
for (unsigned i = 0; i != NumValues; ++i) {
SDValue L = DAG.getLoad(ValueVTs[i], getCurDebugLoc(), Root,
DAG.getNode(ISD::ADD, getCurDebugLoc(),
PtrVT, Ptr,
DAG.getConstant(Offsets[i], PtrVT)),
SV, Offsets[i],
isVolatile, Alignment);
Values[i] = L;
Chains[i] = L.getValue(1);
}
if (!ConstantMemory) {
SDValue Chain = DAG.getNode(ISD::TokenFactor, getCurDebugLoc(),
MVT::Other,
&Chains[0], NumValues);
if (isVolatile)
DAG.setRoot(Chain);
else
PendingLoads.push_back(Chain);
}
setValue(&I, DAG.getNode(ISD::MERGE_VALUES, getCurDebugLoc(),
DAG.getVTList(&ValueVTs[0], NumValues),
&Values[0], NumValues));
}
void SelectionDAGLowering::visitStore(StoreInst &I) {
Value *SrcV = I.getOperand(0);
Value *PtrV = I.getOperand(1);
SmallVector<MVT, 4> ValueVTs;
SmallVector<uint64_t, 4> Offsets;
ComputeValueVTs(TLI, SrcV->getType(), ValueVTs, &Offsets);
unsigned NumValues = ValueVTs.size();
if (NumValues == 0)
return;
// Get the lowered operands. Note that we do this after
// checking if NumResults is zero, because with zero results
// the operands won't have values in the map.
SDValue Src = getValue(SrcV);
SDValue Ptr = getValue(PtrV);
SDValue Root = getRoot();
SmallVector<SDValue, 4> Chains(NumValues);
MVT PtrVT = Ptr.getValueType();
bool isVolatile = I.isVolatile();
unsigned Alignment = I.getAlignment();
for (unsigned i = 0; i != NumValues; ++i)
Chains[i] = DAG.getStore(Root, getCurDebugLoc(),
SDValue(Src.getNode(), Src.getResNo() + i),
DAG.getNode(ISD::ADD, getCurDebugLoc(),
PtrVT, Ptr,
DAG.getConstant(Offsets[i], PtrVT)),
PtrV, Offsets[i],
isVolatile, Alignment);
DAG.setRoot(DAG.getNode(ISD::TokenFactor, getCurDebugLoc(),
MVT::Other, &Chains[0], NumValues));
}
/// visitTargetIntrinsic - Lower a call of a target intrinsic to an INTRINSIC
/// node.
void SelectionDAGLowering::visitTargetIntrinsic(CallInst &I,
unsigned Intrinsic) {
bool HasChain = !I.doesNotAccessMemory();
bool OnlyLoad = HasChain && I.onlyReadsMemory();
// Build the operand list.
SmallVector<SDValue, 8> Ops;
if (HasChain) { // If this intrinsic has side-effects, chainify it.
if (OnlyLoad) {
// We don't need to serialize loads against other loads.
Ops.push_back(DAG.getRoot());
} else {
Ops.push_back(getRoot());
}
}
// Info is set by getTgtMemInstrinsic
TargetLowering::IntrinsicInfo Info;
bool IsTgtIntrinsic = TLI.getTgtMemIntrinsic(Info, I, Intrinsic);
// Add the intrinsic ID as an integer operand if it's not a target intrinsic.
if (!IsTgtIntrinsic)
Ops.push_back(DAG.getConstant(Intrinsic, TLI.getPointerTy()));
// Add all operands of the call to the operand list.
for (unsigned i = 1, e = I.getNumOperands(); i != e; ++i) {
SDValue Op = getValue(I.getOperand(i));
assert(TLI.isTypeLegal(Op.getValueType()) &&
"Intrinsic uses a non-legal type?");
Ops.push_back(Op);
}
std::vector<MVT> VTArray;
if (I.getType() != Type::VoidTy) {
MVT VT = TLI.getValueType(I.getType());
if (VT.isVector()) {
const VectorType *DestTy = cast<VectorType>(I.getType());
MVT EltVT = TLI.getValueType(DestTy->getElementType());
VT = MVT::getVectorVT(EltVT, DestTy->getNumElements());
assert(VT != MVT::Other && "Intrinsic uses a non-legal type?");
}
assert(TLI.isTypeLegal(VT) && "Intrinsic uses a non-legal type?");
VTArray.push_back(VT);
}
if (HasChain)
VTArray.push_back(MVT::Other);
SDVTList VTs = DAG.getVTList(&VTArray[0], VTArray.size());
// Create the node.
SDValue Result;
if (IsTgtIntrinsic) {
// This is target intrinsic that touches memory
Result = DAG.getMemIntrinsicNode(Info.opc, getCurDebugLoc(),
VTs, &Ops[0], Ops.size(),
Info.memVT, Info.ptrVal, Info.offset,
Info.align, Info.vol,
Info.readMem, Info.writeMem);
}
else if (!HasChain)
Result = DAG.getNode(ISD::INTRINSIC_WO_CHAIN, getCurDebugLoc(),
VTs, &Ops[0], Ops.size());
else if (I.getType() != Type::VoidTy)
Result = DAG.getNode(ISD::INTRINSIC_W_CHAIN, getCurDebugLoc(),
VTs, &Ops[0], Ops.size());
else
Result = DAG.getNode(ISD::INTRINSIC_VOID, getCurDebugLoc(),
VTs, &Ops[0], Ops.size());
if (HasChain) {
SDValue Chain = Result.getValue(Result.getNode()->getNumValues()-1);
if (OnlyLoad)
PendingLoads.push_back(Chain);
else
DAG.setRoot(Chain);
}
if (I.getType() != Type::VoidTy) {
if (const VectorType *PTy = dyn_cast<VectorType>(I.getType())) {
MVT VT = TLI.getValueType(PTy);
Result = DAG.getNode(ISD::BIT_CONVERT, getCurDebugLoc(), VT, Result);
}
setValue(&I, Result);
}
}
/// ExtractTypeInfo - Returns the type info, possibly bitcast, encoded in V.
static GlobalVariable *ExtractTypeInfo(Value *V) {
V = V->stripPointerCasts();
GlobalVariable *GV = dyn_cast<GlobalVariable>(V);
assert ((GV || isa<ConstantPointerNull>(V)) &&
"TypeInfo must be a global variable or NULL");
return GV;
}
namespace llvm {
/// AddCatchInfo - Extract the personality and type infos from an eh.selector
/// call, and add them to the specified machine basic block.
void AddCatchInfo(CallInst &I, MachineModuleInfo *MMI,
MachineBasicBlock *MBB) {
// Inform the MachineModuleInfo of the personality for this landing pad.
ConstantExpr *CE = cast<ConstantExpr>(I.getOperand(2));
assert(CE->getOpcode() == Instruction::BitCast &&
isa<Function>(CE->getOperand(0)) &&
"Personality should be a function");
MMI->addPersonality(MBB, cast<Function>(CE->getOperand(0)));
// Gather all the type infos for this landing pad and pass them along to
// MachineModuleInfo.
std::vector<GlobalVariable *> TyInfo;
unsigned N = I.getNumOperands();
for (unsigned i = N - 1; i > 2; --i) {
if (ConstantInt *CI = dyn_cast<ConstantInt>(I.getOperand(i))) {
unsigned FilterLength = CI->getZExtValue();
unsigned FirstCatch = i + FilterLength + !FilterLength;
assert (FirstCatch <= N && "Invalid filter length");
if (FirstCatch < N) {
TyInfo.reserve(N - FirstCatch);
for (unsigned j = FirstCatch; j < N; ++j)
TyInfo.push_back(ExtractTypeInfo(I.getOperand(j)));
MMI->addCatchTypeInfo(MBB, TyInfo);
TyInfo.clear();
}
if (!FilterLength) {
// Cleanup.
MMI->addCleanup(MBB);
} else {
// Filter.
TyInfo.reserve(FilterLength - 1);
for (unsigned j = i + 1; j < FirstCatch; ++j)
TyInfo.push_back(ExtractTypeInfo(I.getOperand(j)));
MMI->addFilterTypeInfo(MBB, TyInfo);
TyInfo.clear();
}
N = i;
}
}
if (N > 3) {
TyInfo.reserve(N - 3);
for (unsigned j = 3; j < N; ++j)
TyInfo.push_back(ExtractTypeInfo(I.getOperand(j)));
MMI->addCatchTypeInfo(MBB, TyInfo);
}
}
}
/// GetSignificand - Get the significand and build it into a floating-point
/// number with exponent of 1:
///
/// Op = (Op & 0x007fffff) | 0x3f800000;
///
/// where Op is the hexidecimal representation of floating point value.
static SDValue
GetSignificand(SelectionDAG &DAG, SDValue Op, DebugLoc dl) {
SDValue t1 = DAG.getNode(ISD::AND, dl, MVT::i32, Op,
DAG.getConstant(0x007fffff, MVT::i32));
SDValue t2 = DAG.getNode(ISD::OR, dl, MVT::i32, t1,
DAG.getConstant(0x3f800000, MVT::i32));
return DAG.getNode(ISD::BIT_CONVERT, dl, MVT::f32, t2);
}
/// GetExponent - Get the exponent:
///
/// (float)(int)(((Op & 0x7f800000) >> 23) - 127);
///
/// where Op is the hexidecimal representation of floating point value.
static SDValue
GetExponent(SelectionDAG &DAG, SDValue Op, const TargetLowering &TLI,
DebugLoc dl) {
SDValue t0 = DAG.getNode(ISD::AND, dl, MVT::i32, Op,
DAG.getConstant(0x7f800000, MVT::i32));
SDValue t1 = DAG.getNode(ISD::SRL, dl, MVT::i32, t0,
DAG.getConstant(23, TLI.getPointerTy()));
SDValue t2 = DAG.getNode(ISD::SUB, dl, MVT::i32, t1,
DAG.getConstant(127, MVT::i32));
return DAG.getNode(ISD::SINT_TO_FP, dl, MVT::f32, t2);
}
/// getF32Constant - Get 32-bit floating point constant.
static SDValue
getF32Constant(SelectionDAG &DAG, unsigned Flt) {
return DAG.getConstantFP(APFloat(APInt(32, Flt)), MVT::f32);
}
/// Inlined utility function to implement binary input atomic intrinsics for
/// visitIntrinsicCall: I is a call instruction
/// Op is the associated NodeType for I
const char *
SelectionDAGLowering::implVisitBinaryAtomic(CallInst& I, ISD::NodeType Op) {
SDValue Root = getRoot();
SDValue L =
DAG.getAtomic(Op, getCurDebugLoc(),
getValue(I.getOperand(2)).getValueType().getSimpleVT(),
Root,
getValue(I.getOperand(1)),
getValue(I.getOperand(2)),
I.getOperand(1));
setValue(&I, L);
DAG.setRoot(L.getValue(1));
return 0;
}
// implVisitAluOverflow - Lower arithmetic overflow instrinsics.
const char *
SelectionDAGLowering::implVisitAluOverflow(CallInst &I, ISD::NodeType Op) {
SDValue Op1 = getValue(I.getOperand(1));
SDValue Op2 = getValue(I.getOperand(2));
SDVTList VTs = DAG.getVTList(Op1.getValueType(), MVT::i1);
SDValue Result = DAG.getNode(Op, getCurDebugLoc(), VTs, Op1, Op2);
setValue(&I, Result);
return 0;
}
/// visitExp - Lower an exp intrinsic. Handles the special sequences for
/// limited-precision mode.
void
SelectionDAGLowering::visitExp(CallInst &I) {
SDValue result;
DebugLoc dl = getCurDebugLoc();
if (getValue(I.getOperand(1)).getValueType() == MVT::f32 &&
LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) {
SDValue Op = getValue(I.getOperand(1));
// Put the exponent in the right bit position for later addition to the
// final result:
//
// #define LOG2OFe 1.4426950f
// IntegerPartOfX = ((int32_t)(X * LOG2OFe));
SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, Op,
getF32Constant(DAG, 0x3fb8aa3b));
SDValue IntegerPartOfX = DAG.getNode(ISD::FP_TO_SINT, dl, MVT::i32, t0);
// FractionalPartOfX = (X * LOG2OFe) - (float)IntegerPartOfX;
SDValue t1 = DAG.getNode(ISD::SINT_TO_FP, dl, MVT::f32, IntegerPartOfX);
SDValue X = DAG.getNode(ISD::FSUB, dl, MVT::f32, t0, t1);
// IntegerPartOfX <<= 23;
IntegerPartOfX = DAG.getNode(ISD::SHL, dl, MVT::i32, IntegerPartOfX,
DAG.getConstant(23, TLI.getPointerTy()));
if (LimitFloatPrecision <= 6) {
// For floating-point precision of 6:
//
// TwoToFractionalPartOfX =
// 0.997535578f +
// (0.735607626f + 0.252464424f * x) * x;
//
// error 0.0144103317, which is 6 bits
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0x3e814304));
SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3f3c50c8));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x3f7f5e7e));
SDValue TwoToFracPartOfX = DAG.getNode(ISD::BIT_CONVERT, dl,MVT::i32, t5);
// Add the exponent into the result in integer domain.
SDValue t6 = DAG.getNode(ISD::ADD, dl, MVT::i32,
TwoToFracPartOfX, IntegerPartOfX);
result = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::f32, t6);
} else if (LimitFloatPrecision > 6 && LimitFloatPrecision <= 12) {
// For floating-point precision of 12:
//
// TwoToFractionalPartOfX =
// 0.999892986f +
// (0.696457318f +
// (0.224338339f + 0.792043434e-1f * x) * x) * x;
//
// 0.000107046256 error, which is 13 to 14 bits
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0x3da235e3));
SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3e65b8f3));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x3f324b07));
SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X);
SDValue t7 = DAG.getNode(ISD::FADD, dl, MVT::f32, t6,
getF32Constant(DAG, 0x3f7ff8fd));
SDValue TwoToFracPartOfX = DAG.getNode(ISD::BIT_CONVERT, dl,MVT::i32, t7);
// Add the exponent into the result in integer domain.
SDValue t8 = DAG.getNode(ISD::ADD, dl, MVT::i32,
TwoToFracPartOfX, IntegerPartOfX);
result = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::f32, t8);
} else { // LimitFloatPrecision > 12 && LimitFloatPrecision <= 18
// For floating-point precision of 18:
//
// TwoToFractionalPartOfX =
// 0.999999982f +
// (0.693148872f +
// (0.240227044f +
// (0.554906021e-1f +
// (0.961591928e-2f +
// (0.136028312e-2f + 0.157059148e-3f *x)*x)*x)*x)*x)*x;
//
// error 2.47208000*10^(-7), which is better than 18 bits
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0x3924b03e));
SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3ab24b87));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x3c1d8c17));
SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X);
SDValue t7 = DAG.getNode(ISD::FADD, dl, MVT::f32, t6,
getF32Constant(DAG, 0x3d634a1d));
SDValue t8 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t7, X);
SDValue t9 = DAG.getNode(ISD::FADD, dl, MVT::f32, t8,
getF32Constant(DAG, 0x3e75fe14));
SDValue t10 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t9, X);
SDValue t11 = DAG.getNode(ISD::FADD, dl, MVT::f32, t10,
getF32Constant(DAG, 0x3f317234));
SDValue t12 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t11, X);
SDValue t13 = DAG.getNode(ISD::FADD, dl, MVT::f32, t12,
getF32Constant(DAG, 0x3f800000));
SDValue TwoToFracPartOfX = DAG.getNode(ISD::BIT_CONVERT, dl,
MVT::i32, t13);
// Add the exponent into the result in integer domain.
SDValue t14 = DAG.getNode(ISD::ADD, dl, MVT::i32,
TwoToFracPartOfX, IntegerPartOfX);
result = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::f32, t14);
}
} else {
// No special expansion.
result = DAG.getNode(ISD::FEXP, dl,
getValue(I.getOperand(1)).getValueType(),
getValue(I.getOperand(1)));
}
setValue(&I, result);
}
/// visitLog - Lower a log intrinsic. Handles the special sequences for
/// limited-precision mode.
void
SelectionDAGLowering::visitLog(CallInst &I) {
SDValue result;
DebugLoc dl = getCurDebugLoc();
if (getValue(I.getOperand(1)).getValueType() == MVT::f32 &&
LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) {
SDValue Op = getValue(I.getOperand(1));
SDValue Op1 = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::i32, Op);
// Scale the exponent by log(2) [0.69314718f].
SDValue Exp = GetExponent(DAG, Op1, TLI, dl);
SDValue LogOfExponent = DAG.getNode(ISD::FMUL, dl, MVT::f32, Exp,
getF32Constant(DAG, 0x3f317218));
// Get the significand and build it into a floating-point number with
// exponent of 1.
SDValue X = GetSignificand(DAG, Op1, dl);
if (LimitFloatPrecision <= 6) {
// For floating-point precision of 6:
//
// LogofMantissa =
// -1.1609546f +
// (1.4034025f - 0.23903021f * x) * x;
//
// error 0.0034276066, which is better than 8 bits
SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0xbe74c456));
SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0,
getF32Constant(DAG, 0x3fb3a2b1));
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X);
SDValue LogOfMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3f949a29));
result = DAG.getNode(ISD::FADD, dl,
MVT::f32, LogOfExponent, LogOfMantissa);
} else if (LimitFloatPrecision > 6 && LimitFloatPrecision <= 12) {
// For floating-point precision of 12:
//
// LogOfMantissa =
// -1.7417939f +
// (2.8212026f +
// (-1.4699568f +
// (0.44717955f - 0.56570851e-1f * x) * x) * x) * x;
//
// error 0.000061011436, which is 14 bits
SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0xbd67b6d6));
SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0,
getF32Constant(DAG, 0x3ee4f4b8));
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X);
SDValue t3 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3fbc278b));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x40348e95));
SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X);
SDValue LogOfMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t6,
getF32Constant(DAG, 0x3fdef31a));
result = DAG.getNode(ISD::FADD, dl,
MVT::f32, LogOfExponent, LogOfMantissa);
} else { // LimitFloatPrecision > 12 && LimitFloatPrecision <= 18
// For floating-point precision of 18:
//
// LogOfMantissa =
// -2.1072184f +
// (4.2372794f +
// (-3.7029485f +
// (2.2781945f +
// (-0.87823314f +
// (0.19073739f - 0.17809712e-1f * x) * x) * x) * x) * x)*x;
//
// error 0.0000023660568, which is better than 18 bits
SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0xbc91e5ac));
SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0,
getF32Constant(DAG, 0x3e4350aa));
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X);
SDValue t3 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3f60d3e3));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x4011cdf0));
SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X);
SDValue t7 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t6,
getF32Constant(DAG, 0x406cfd1c));
SDValue t8 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t7, X);
SDValue t9 = DAG.getNode(ISD::FADD, dl, MVT::f32, t8,
getF32Constant(DAG, 0x408797cb));
SDValue t10 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t9, X);
SDValue LogOfMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t10,
getF32Constant(DAG, 0x4006dcab));
result = DAG.getNode(ISD::FADD, dl,
MVT::f32, LogOfExponent, LogOfMantissa);
}
} else {
// No special expansion.
result = DAG.getNode(ISD::FLOG, dl,
getValue(I.getOperand(1)).getValueType(),
getValue(I.getOperand(1)));
}
setValue(&I, result);
}
/// visitLog2 - Lower a log2 intrinsic. Handles the special sequences for
/// limited-precision mode.
void
SelectionDAGLowering::visitLog2(CallInst &I) {
SDValue result;
DebugLoc dl = getCurDebugLoc();
if (getValue(I.getOperand(1)).getValueType() == MVT::f32 &&
LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) {
SDValue Op = getValue(I.getOperand(1));
SDValue Op1 = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::i32, Op);
// Get the exponent.
SDValue LogOfExponent = GetExponent(DAG, Op1, TLI, dl);
// Get the significand and build it into a floating-point number with
// exponent of 1.
SDValue X = GetSignificand(DAG, Op1, dl);
// Different possible minimax approximations of significand in
// floating-point for various degrees of accuracy over [1,2].
if (LimitFloatPrecision <= 6) {
// For floating-point precision of 6:
//
// Log2ofMantissa = -1.6749035f + (2.0246817f - .34484768f * x) * x;
//
// error 0.0049451742, which is more than 7 bits
SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0xbeb08fe0));
SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0,
getF32Constant(DAG, 0x40019463));
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X);
SDValue Log2ofMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3fd6633d));
result = DAG.getNode(ISD::FADD, dl,
MVT::f32, LogOfExponent, Log2ofMantissa);
} else if (LimitFloatPrecision > 6 && LimitFloatPrecision <= 12) {
// For floating-point precision of 12:
//
// Log2ofMantissa =
// -2.51285454f +
// (4.07009056f +
// (-2.12067489f +
// (.645142248f - 0.816157886e-1f * x) * x) * x) * x;
//
// error 0.0000876136000, which is better than 13 bits
SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0xbda7262e));
SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0,
getF32Constant(DAG, 0x3f25280b));
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X);
SDValue t3 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2,
getF32Constant(DAG, 0x4007b923));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x40823e2f));
SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X);
SDValue Log2ofMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t6,
getF32Constant(DAG, 0x4020d29c));
result = DAG.getNode(ISD::FADD, dl,
MVT::f32, LogOfExponent, Log2ofMantissa);
} else { // LimitFloatPrecision > 12 && LimitFloatPrecision <= 18
// For floating-point precision of 18:
//
// Log2ofMantissa =
// -3.0400495f +
// (6.1129976f +
// (-5.3420409f +
// (3.2865683f +
// (-1.2669343f +
// (0.27515199f -
// 0.25691327e-1f * x) * x) * x) * x) * x) * x;
//
// error 0.0000018516, which is better than 18 bits
SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0xbcd2769e));
SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0,
getF32Constant(DAG, 0x3e8ce0b9));
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X);
SDValue t3 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3fa22ae7));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x40525723));
SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X);
SDValue t7 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t6,
getF32Constant(DAG, 0x40aaf200));
SDValue t8 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t7, X);
SDValue t9 = DAG.getNode(ISD::FADD, dl, MVT::f32, t8,
getF32Constant(DAG, 0x40c39dad));
SDValue t10 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t9, X);
SDValue Log2ofMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t10,
getF32Constant(DAG, 0x4042902c));
result = DAG.getNode(ISD::FADD, dl,
MVT::f32, LogOfExponent, Log2ofMantissa);
}
} else {
// No special expansion.
result = DAG.getNode(ISD::FLOG2, dl,
getValue(I.getOperand(1)).getValueType(),
getValue(I.getOperand(1)));
}
setValue(&I, result);
}
/// visitLog10 - Lower a log10 intrinsic. Handles the special sequences for
/// limited-precision mode.
void
SelectionDAGLowering::visitLog10(CallInst &I) {
SDValue result;
DebugLoc dl = getCurDebugLoc();
if (getValue(I.getOperand(1)).getValueType() == MVT::f32 &&
LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) {
SDValue Op = getValue(I.getOperand(1));
SDValue Op1 = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::i32, Op);
// Scale the exponent by log10(2) [0.30102999f].
SDValue Exp = GetExponent(DAG, Op1, TLI, dl);
SDValue LogOfExponent = DAG.getNode(ISD::FMUL, dl, MVT::f32, Exp,
getF32Constant(DAG, 0x3e9a209a));
// Get the significand and build it into a floating-point number with
// exponent of 1.
SDValue X = GetSignificand(DAG, Op1, dl);
if (LimitFloatPrecision <= 6) {
// For floating-point precision of 6:
//
// Log10ofMantissa =
// -0.50419619f +
// (0.60948995f - 0.10380950f * x) * x;
//
// error 0.0014886165, which is 6 bits
SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0xbdd49a13));
SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0,
getF32Constant(DAG, 0x3f1c0789));
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X);
SDValue Log10ofMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3f011300));
result = DAG.getNode(ISD::FADD, dl,
MVT::f32, LogOfExponent, Log10ofMantissa);
} else if (LimitFloatPrecision > 6 && LimitFloatPrecision <= 12) {
// For floating-point precision of 12:
//
// Log10ofMantissa =
// -0.64831180f +
// (0.91751397f +
// (-0.31664806f + 0.47637168e-1f * x) * x) * x;
//
// error 0.00019228036, which is better than 12 bits
SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0x3d431f31));
SDValue t1 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t0,
getF32Constant(DAG, 0x3ea21fb2));
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X);
SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3f6ae232));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue Log10ofMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t4,
getF32Constant(DAG, 0x3f25f7c3));
result = DAG.getNode(ISD::FADD, dl,
MVT::f32, LogOfExponent, Log10ofMantissa);
} else { // LimitFloatPrecision > 12 && LimitFloatPrecision <= 18
// For floating-point precision of 18:
//
// Log10ofMantissa =
// -0.84299375f +
// (1.5327582f +
// (-1.0688956f +
// (0.49102474f +
// (-0.12539807f + 0.13508273e-1f * x) * x) * x) * x) * x;
//
// error 0.0000037995730, which is better than 18 bits
SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0x3c5d51ce));
SDValue t1 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t0,
getF32Constant(DAG, 0x3e00685a));
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X);
SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3efb6798));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t4,
getF32Constant(DAG, 0x3f88d192));
SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X);
SDValue t7 = DAG.getNode(ISD::FADD, dl, MVT::f32, t6,
getF32Constant(DAG, 0x3fc4316c));
SDValue t8 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t7, X);
SDValue Log10ofMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t8,
getF32Constant(DAG, 0x3f57ce70));
result = DAG.getNode(ISD::FADD, dl,
MVT::f32, LogOfExponent, Log10ofMantissa);
}
} else {
// No special expansion.
result = DAG.getNode(ISD::FLOG10, dl,
getValue(I.getOperand(1)).getValueType(),
getValue(I.getOperand(1)));
}
setValue(&I, result);
}
/// visitExp2 - Lower an exp2 intrinsic. Handles the special sequences for
/// limited-precision mode.
void
SelectionDAGLowering::visitExp2(CallInst &I) {
SDValue result;
DebugLoc dl = getCurDebugLoc();
if (getValue(I.getOperand(1)).getValueType() == MVT::f32 &&
LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) {
SDValue Op = getValue(I.getOperand(1));
SDValue IntegerPartOfX = DAG.getNode(ISD::FP_TO_SINT, dl, MVT::i32, Op);
// FractionalPartOfX = x - (float)IntegerPartOfX;
SDValue t1 = DAG.getNode(ISD::SINT_TO_FP, dl, MVT::f32, IntegerPartOfX);
SDValue X = DAG.getNode(ISD::FSUB, dl, MVT::f32, Op, t1);
// IntegerPartOfX <<= 23;
IntegerPartOfX = DAG.getNode(ISD::SHL, dl, MVT::i32, IntegerPartOfX,
DAG.getConstant(23, TLI.getPointerTy()));
if (LimitFloatPrecision <= 6) {
// For floating-point precision of 6:
//
// TwoToFractionalPartOfX =
// 0.997535578f +
// (0.735607626f + 0.252464424f * x) * x;
//
// error 0.0144103317, which is 6 bits
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0x3e814304));
SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3f3c50c8));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x3f7f5e7e));
SDValue t6 = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::i32, t5);
SDValue TwoToFractionalPartOfX =
DAG.getNode(ISD::ADD, dl, MVT::i32, t6, IntegerPartOfX);
result = DAG.getNode(ISD::BIT_CONVERT, dl,
MVT::f32, TwoToFractionalPartOfX);
} else if (LimitFloatPrecision > 6 && LimitFloatPrecision <= 12) {
// For floating-point precision of 12:
//
// TwoToFractionalPartOfX =
// 0.999892986f +
// (0.696457318f +
// (0.224338339f + 0.792043434e-1f * x) * x) * x;
//
// error 0.000107046256, which is 13 to 14 bits
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0x3da235e3));
SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3e65b8f3));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x3f324b07));
SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X);
SDValue t7 = DAG.getNode(ISD::FADD, dl, MVT::f32, t6,
getF32Constant(DAG, 0x3f7ff8fd));
SDValue t8 = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::i32, t7);
SDValue TwoToFractionalPartOfX =
DAG.getNode(ISD::ADD, dl, MVT::i32, t8, IntegerPartOfX);
result = DAG.getNode(ISD::BIT_CONVERT, dl,
MVT::f32, TwoToFractionalPartOfX);
} else { // LimitFloatPrecision > 12 && LimitFloatPrecision <= 18
// For floating-point precision of 18:
//
// TwoToFractionalPartOfX =
// 0.999999982f +
// (0.693148872f +
// (0.240227044f +
// (0.554906021e-1f +
// (0.961591928e-2f +
// (0.136028312e-2f + 0.157059148e-3f *x)*x)*x)*x)*x)*x;
// error 2.47208000*10^(-7), which is better than 18 bits
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0x3924b03e));
SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3ab24b87));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x3c1d8c17));
SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X);
SDValue t7 = DAG.getNode(ISD::FADD, dl, MVT::f32, t6,
getF32Constant(DAG, 0x3d634a1d));
SDValue t8 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t7, X);
SDValue t9 = DAG.getNode(ISD::FADD, dl, MVT::f32, t8,
getF32Constant(DAG, 0x3e75fe14));
SDValue t10 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t9, X);
SDValue t11 = DAG.getNode(ISD::FADD, dl, MVT::f32, t10,
getF32Constant(DAG, 0x3f317234));
SDValue t12 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t11, X);
SDValue t13 = DAG.getNode(ISD::FADD, dl, MVT::f32, t12,
getF32Constant(DAG, 0x3f800000));
SDValue t14 = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::i32, t13);
SDValue TwoToFractionalPartOfX =
DAG.getNode(ISD::ADD, dl, MVT::i32, t14, IntegerPartOfX);
result = DAG.getNode(ISD::BIT_CONVERT, dl,
MVT::f32, TwoToFractionalPartOfX);
}
} else {
// No special expansion.
result = DAG.getNode(ISD::FEXP2, dl,
getValue(I.getOperand(1)).getValueType(),
getValue(I.getOperand(1)));
}
setValue(&I, result);
}
/// visitPow - Lower a pow intrinsic. Handles the special sequences for
/// limited-precision mode with x == 10.0f.
void
SelectionDAGLowering::visitPow(CallInst &I) {
SDValue result;
Value *Val = I.getOperand(1);
DebugLoc dl = getCurDebugLoc();
bool IsExp10 = false;
if (getValue(Val).getValueType() == MVT::f32 &&
getValue(I.getOperand(2)).getValueType() == MVT::f32 &&
LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) {
if (Constant *C = const_cast<Constant*>(dyn_cast<Constant>(Val))) {
if (ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
APFloat Ten(10.0f);
IsExp10 = CFP->getValueAPF().bitwiseIsEqual(Ten);
}
}
}
if (IsExp10 && LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) {
SDValue Op = getValue(I.getOperand(2));
// Put the exponent in the right bit position for later addition to the
// final result:
//
// #define LOG2OF10 3.3219281f
// IntegerPartOfX = (int32_t)(x * LOG2OF10);
SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, Op,
getF32Constant(DAG, 0x40549a78));
SDValue IntegerPartOfX = DAG.getNode(ISD::FP_TO_SINT, dl, MVT::i32, t0);
// FractionalPartOfX = x - (float)IntegerPartOfX;
SDValue t1 = DAG.getNode(ISD::SINT_TO_FP, dl, MVT::f32, IntegerPartOfX);
SDValue X = DAG.getNode(ISD::FSUB, dl, MVT::f32, t0, t1);
// IntegerPartOfX <<= 23;
IntegerPartOfX = DAG.getNode(ISD::SHL, dl, MVT::i32, IntegerPartOfX,
DAG.getConstant(23, TLI.getPointerTy()));
if (LimitFloatPrecision <= 6) {
// For floating-point precision of 6:
//
// twoToFractionalPartOfX =
// 0.997535578f +
// (0.735607626f + 0.252464424f * x) * x;
//
// error 0.0144103317, which is 6 bits
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0x3e814304));
SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3f3c50c8));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x3f7f5e7e));
SDValue t6 = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::i32, t5);
SDValue TwoToFractionalPartOfX =
DAG.getNode(ISD::ADD, dl, MVT::i32, t6, IntegerPartOfX);
result = DAG.getNode(ISD::BIT_CONVERT, dl,
MVT::f32, TwoToFractionalPartOfX);
} else if (LimitFloatPrecision > 6 && LimitFloatPrecision <= 12) {
// For floating-point precision of 12:
//
// TwoToFractionalPartOfX =
// 0.999892986f +
// (0.696457318f +
// (0.224338339f + 0.792043434e-1f * x) * x) * x;
//
// error 0.000107046256, which is 13 to 14 bits
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0x3da235e3));
SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3e65b8f3));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x3f324b07));
SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X);
SDValue t7 = DAG.getNode(ISD::FADD, dl, MVT::f32, t6,
getF32Constant(DAG, 0x3f7ff8fd));
SDValue t8 = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::i32, t7);
SDValue TwoToFractionalPartOfX =
DAG.getNode(ISD::ADD, dl, MVT::i32, t8, IntegerPartOfX);
result = DAG.getNode(ISD::BIT_CONVERT, dl,
MVT::f32, TwoToFractionalPartOfX);
} else { // LimitFloatPrecision > 12 && LimitFloatPrecision <= 18
// For floating-point precision of 18:
//
// TwoToFractionalPartOfX =
// 0.999999982f +
// (0.693148872f +
// (0.240227044f +
// (0.554906021e-1f +
// (0.961591928e-2f +
// (0.136028312e-2f + 0.157059148e-3f *x)*x)*x)*x)*x)*x;
// error 2.47208000*10^(-7), which is better than 18 bits
SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X,
getF32Constant(DAG, 0x3924b03e));
SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2,
getF32Constant(DAG, 0x3ab24b87));
SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
getF32Constant(DAG, 0x3c1d8c17));
SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X);
SDValue t7 = DAG.getNode(ISD::FADD, dl, MVT::f32, t6,
getF32Constant(DAG, 0x3d634a1d));
SDValue t8 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t7, X);
SDValue t9 = DAG.getNode(ISD::FADD, dl, MVT::f32, t8,
getF32Constant(DAG, 0x3e75fe14));
SDValue t10 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t9, X);
SDValue t11 = DAG.getNode(ISD::FADD, dl, MVT::f32, t10,
getF32Constant(DAG, 0x3f317234));
SDValue t12 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t11, X);
SDValue t13 = DAG.getNode(ISD::FADD, dl, MVT::f32, t12,
getF32Constant(DAG, 0x3f800000));
SDValue t14 = DAG.getNode(ISD::BIT_CONVERT, dl, MVT::i32, t13);
SDValue TwoToFractionalPartOfX =
DAG.getNode(ISD::ADD, dl, MVT::i32, t14, IntegerPartOfX);
result = DAG.getNode(ISD::BIT_CONVERT, dl,
MVT::f32, TwoToFractionalPartOfX);
}
} else {
// No special expansion.
result = DAG.getNode(ISD::FPOW, dl,
getValue(I.getOperand(1)).getValueType(),
getValue(I.getOperand(1)),
getValue(I.getOperand(2)));
}
setValue(&I, result);
}
/// visitIntrinsicCall - Lower the call to the specified intrinsic function. If
/// we want to emit this as a call to a named external function, return the name
/// otherwise lower it and return null.
const char *
SelectionDAGLowering::visitIntrinsicCall(CallInst &I, unsigned Intrinsic) {
DebugLoc dl = getCurDebugLoc();
switch (Intrinsic) {
default:
// By default, turn this into a target intrinsic node.
visitTargetIntrinsic(I, Intrinsic);
return 0;
case Intrinsic::vastart: visitVAStart(I); return 0;
case Intrinsic::vaend: visitVAEnd(I); return 0;
case Intrinsic::vacopy: visitVACopy(I); return 0;
case Intrinsic::returnaddress:
setValue(&I, DAG.getNode(ISD::RETURNADDR, dl, TLI.getPointerTy(),
getValue(I.getOperand(1))));
return 0;
case Intrinsic::frameaddress:
setValue(&I, DAG.getNode(ISD::FRAMEADDR, dl, TLI.getPointerTy(),
getValue(I.getOperand(1))));
return 0;
case Intrinsic::setjmp:
return "_setjmp"+!TLI.usesUnderscoreSetJmp();
break;
case Intrinsic::longjmp:
return "_longjmp"+!TLI.usesUnderscoreLongJmp();
break;
case Intrinsic::memcpy: {
SDValue Op1 = getValue(I.getOperand(1));
SDValue Op2 = getValue(I.getOperand(2));
SDValue Op3 = getValue(I.getOperand(3));
unsigned Align = cast<ConstantInt>(I.getOperand(4))->getZExtValue();
DAG.setRoot(DAG.getMemcpy(getRoot(), dl, Op1, Op2, Op3, Align, false,
I.getOperand(1), 0, I.getOperand(2), 0));
return 0;
}
case Intrinsic::memset: {
SDValue Op1 = getValue(I.getOperand(1));
SDValue Op2 = getValue(I.getOperand(2));
SDValue Op3 = getValue(I.getOperand(3));
unsigned Align = cast<ConstantInt>(I.getOperand(4))->getZExtValue();
DAG.setRoot(DAG.getMemset(getRoot(), dl, Op1, Op2, Op3, Align,
I.getOperand(1), 0));
return 0;
}
case Intrinsic::memmove: {
SDValue Op1 = getValue(I.getOperand(1));
SDValue Op2 = getValue(I.getOperand(2));
SDValue Op3 = getValue(I.getOperand(3));
unsigned Align = cast<ConstantInt>(I.getOperand(4))->getZExtValue();
// If the source and destination are known to not be aliases, we can
// lower memmove as memcpy.
uint64_t Size = -1ULL;
if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op3))
Size = C->getZExtValue();
if (AA->alias(I.getOperand(1), Size, I.getOperand(2), Size) ==
AliasAnalysis::NoAlias) {
DAG.setRoot(DAG.getMemcpy(getRoot(), dl, Op1, Op2, Op3, Align, false,
I.getOperand(1), 0, I.getOperand(2), 0));
return 0;
}
DAG.setRoot(DAG.getMemmove(getRoot(), dl, Op1, Op2, Op3, Align,
I.getOperand(1), 0, I.getOperand(2), 0));
return 0;
}
case Intrinsic::dbg_stoppoint: {
DbgStopPointInst &SPI = cast<DbgStopPointInst>(I);
if (DIDescriptor::ValidDebugInfo(SPI.getContext(), OptLevel)) {
MachineFunction &MF = DAG.getMachineFunction();
DICompileUnit CU(cast<GlobalVariable>(SPI.getContext()));
DebugLoc Loc = DebugLoc::get(MF.getOrCreateDebugLocID(CU.getGV(),
SPI.getLine(), SPI.getColumn()));
setCurDebugLoc(Loc);
if (OptLevel == CodeGenOpt::None)
DAG.setRoot(DAG.getDbgStopPoint(Loc, getRoot(),
SPI.getLine(),
SPI.getColumn(),
SPI.getContext()));
}
return 0;
}
case Intrinsic::dbg_region_start: {
DwarfWriter *DW = DAG.getDwarfWriter();
DbgRegionStartInst &RSI = cast<DbgRegionStartInst>(I);
if (DIDescriptor::ValidDebugInfo(RSI.getContext(), OptLevel) &&
DW && DW->ShouldEmitDwarfDebug()) {
unsigned LabelID =
DW->RecordRegionStart(cast<GlobalVariable>(RSI.getContext()));
DAG.setRoot(DAG.getLabel(ISD::DBG_LABEL, getCurDebugLoc(),
getRoot(), LabelID));
}
return 0;
}
case Intrinsic::dbg_region_end: {
DwarfWriter *DW = DAG.getDwarfWriter();
DbgRegionEndInst &REI = cast<DbgRegionEndInst>(I);
if (DIDescriptor::ValidDebugInfo(REI.getContext(), OptLevel) &&
DW && DW->ShouldEmitDwarfDebug()) {
MachineFunction &MF = DAG.getMachineFunction();
DISubprogram Subprogram(cast<GlobalVariable>(REI.getContext()));
if (Subprogram.isNull() || Subprogram.describes(MF.getFunction())) {
unsigned LabelID =
DW->RecordRegionEnd(cast<GlobalVariable>(REI.getContext()));
DAG.setRoot(DAG.getLabel(ISD::DBG_LABEL, getCurDebugLoc(),
getRoot(), LabelID));
} else {
// This is end of inlined function. Debugging information for inlined
// function is not handled yet (only supported by FastISel).
if (OptLevel == CodeGenOpt::None) {
unsigned ID = DW->RecordInlinedFnEnd(Subprogram);
if (ID != 0)
// Returned ID is 0 if this is unbalanced "end of inlined
// scope". This could happen if optimizer eats dbg intrinsics or
// "beginning of inlined scope" is not recoginized due to missing
// location info. In such cases, do ignore this region.end.
DAG.setRoot(DAG.getLabel(ISD::DBG_LABEL, getCurDebugLoc(),
getRoot(), ID));
}
}
}
return 0;
}
case Intrinsic::dbg_func_start: {
DwarfWriter *DW = DAG.getDwarfWriter();
DbgFuncStartInst &FSI = cast<DbgFuncStartInst>(I);
Value *SP = FSI.getSubprogram();
if (!DIDescriptor::ValidDebugInfo(SP, OptLevel))
return 0;
MachineFunction &MF = DAG.getMachineFunction();
if (OptLevel == CodeGenOpt::None) {
// llvm.dbg.func.start implicitly defines a dbg_stoppoint which is what
// (most?) gdb expects.
DebugLoc PrevLoc = CurDebugLoc;
DISubprogram Subprogram(cast<GlobalVariable>(SP));
DICompileUnit CompileUnit = Subprogram.getCompileUnit();
if (!Subprogram.describes(MF.getFunction())) {
// This is a beginning of an inlined function.
// If llvm.dbg.func.start is seen in a new block before any
// llvm.dbg.stoppoint intrinsic then the location info is unknown.
// FIXME : Why DebugLoc is reset at the beginning of each block ?
if (PrevLoc.isUnknown())
return 0;
// Record the source line.
unsigned Line = Subprogram.getLineNumber();
setCurDebugLoc(DebugLoc::get(
MF.getOrCreateDebugLocID(CompileUnit.getGV(), Line, 0)));
if (DW && DW->ShouldEmitDwarfDebug()) {
DebugLocTuple PrevLocTpl = MF.getDebugLocTuple(PrevLoc);
unsigned LabelID = DW->RecordInlinedFnStart(Subprogram,
DICompileUnit(PrevLocTpl.CompileUnit),
PrevLocTpl.Line,
PrevLocTpl.Col);
DAG.setRoot(DAG.getLabel(ISD::DBG_LABEL, getCurDebugLoc(),
getRoot(), LabelID));
}
} else {
// Record the source line.
unsigned Line = Subprogram.getLineNumber();
MF.setDefaultDebugLoc(DebugLoc::get(
MF.getOrCreateDebugLocID(CompileUnit.getGV(), Line, 0)));
if (DW && DW->ShouldEmitDwarfDebug()) {
// llvm.dbg.func_start also defines beginning of function scope.
DW->RecordRegionStart(cast<GlobalVariable>(FSI.getSubprogram()));
}
}
} else {
DISubprogram Subprogram(cast<GlobalVariable>(SP));
std::string SPName;
Subprogram.getLinkageName(SPName);
if (!SPName.empty()
&& strcmp(SPName.c_str(), MF.getFunction()->getNameStart())) {
// This is beginning of inlined function. Debugging information for
// inlined function is not handled yet (only supported by FastISel).
return 0;
}
// llvm.dbg.func.start implicitly defines a dbg_stoppoint which is
// what (most?) gdb expects.
DICompileUnit CompileUnit = Subprogram.getCompileUnit();
// Record the source line but does not create a label for the normal
// function start. It will be emitted at asm emission time. However,
// create a label if this is a beginning of inlined function.
unsigned Line = Subprogram.getLineNumber();
setCurDebugLoc(DebugLoc::get(
MF.getOrCreateDebugLocID(CompileUnit.getGV(), Line, 0)));
// FIXME - Start new region because llvm.dbg.func_start also defines
// beginning of function scope.
}
return 0;
}
case Intrinsic::dbg_declare: {
if (OptLevel == CodeGenOpt::None) {
DbgDeclareInst &DI = cast<DbgDeclareInst>(I);
Value *Variable = DI.getVariable();
if (DIDescriptor::ValidDebugInfo(Variable, OptLevel))
DAG.setRoot(DAG.getNode(ISD::DECLARE, dl, MVT::Other, getRoot(),
getValue(DI.getAddress()), getValue(Variable)));
} else {
// FIXME: Do something sensible here when we support debug declare.
}
return 0;
}
case Intrinsic::eh_exception: {
// Insert the EXCEPTIONADDR instruction.
assert(CurMBB->isLandingPad() &&"Call to eh.exception not in landing pad!");
SDVTList VTs = DAG.getVTList(TLI.getPointerTy(), MVT::Other);
SDValue Ops[1];
Ops[0] = DAG.getRoot();
SDValue Op = DAG.getNode(ISD::EXCEPTIONADDR, dl, VTs, Ops, 1);
setValue(&I, Op);
DAG.setRoot(Op.getValue(1));
return 0;
}
case Intrinsic::eh_selector_i32:
case Intrinsic::eh_selector_i64: {
MachineModuleInfo *MMI = DAG.getMachineModuleInfo();
MVT VT = (Intrinsic == Intrinsic::eh_selector_i32 ?
MVT::i32 : MVT::i64);
if (MMI) {
if (CurMBB->isLandingPad())
AddCatchInfo(I, MMI, CurMBB);
else {
#ifndef NDEBUG
FuncInfo.CatchInfoLost.insert(&I);
#endif
// FIXME: Mark exception selector register as live in. Hack for PR1508.
unsigned Reg = TLI.getExceptionSelectorRegister();
if (Reg) CurMBB->addLiveIn(Reg);
}
// Insert the EHSELECTION instruction.
SDVTList VTs = DAG.getVTList(VT, MVT::Other);
SDValue Ops[2];
Ops[0] = getValue(I.getOperand(1));
Ops[1] = getRoot();
SDValue Op = DAG.getNode(ISD::EHSELECTION, dl, VTs, Ops, 2);
setValue(&I, Op);
DAG.setRoot(Op.getValue(1));
} else {
setValue(&I, DAG.getConstant(0, VT));
}
return 0;
}
case Intrinsic::eh_typeid_for_i32:
case Intrinsic::eh_typeid_for_i64: {
MachineModuleInfo *MMI = DAG.getMachineModuleInfo();
MVT VT = (Intrinsic == Intrinsic::eh_typeid_for_i32 ?
MVT::i32 : MVT::i64);
if (MMI) {
// Find the type id for the given typeinfo.
GlobalVariable *GV = ExtractTypeInfo(I.getOperand(1));
unsigned TypeID = MMI->getTypeIDFor(GV);
setValue(&I, DAG.getConstant(TypeID, VT));
} else {
// Return something different to eh_selector.
setValue(&I, DAG.getConstant(1, VT));
}
return 0;
}
case Intrinsic::eh_return_i32:
case Intrinsic::eh_return_i64:
if (MachineModuleInfo *MMI = DAG.getMachineModuleInfo()) {
MMI->setCallsEHReturn(true);
DAG.setRoot(DAG.getNode(ISD::EH_RETURN, dl,
MVT::Other,
getControlRoot(),
getValue(I.getOperand(1)),
getValue(I.getOperand(2))));
} else {
setValue(&I, DAG.getConstant(0, TLI.getPointerTy()));
}
return 0;
case Intrinsic::eh_unwind_init:
if (MachineModuleInfo *MMI = DAG.getMachineModuleInfo()) {
MMI->setCallsUnwindInit(true);
}
return 0;
case Intrinsic::eh_dwarf_cfa: {
MVT VT = getValue(I.getOperand(1)).getValueType();
SDValue CfaArg;
if (VT.bitsGT(TLI.getPointerTy()))
CfaArg = DAG.getNode(ISD::TRUNCATE, dl,
TLI.getPointerTy(), getValue(I.getOperand(1)));
else
CfaArg = DAG.getNode(ISD::SIGN_EXTEND, dl,
TLI.getPointerTy(), getValue(I.getOperand(1)));
SDValue Offset = DAG.getNode(ISD::ADD, dl,
TLI.getPointerTy(),
DAG.getNode(ISD::FRAME_TO_ARGS_OFFSET, dl,
TLI.getPointerTy()),
CfaArg);
setValue(&I, DAG.getNode(ISD::ADD, dl,
TLI.getPointerTy(),
DAG.getNode(ISD::FRAMEADDR, dl,
TLI.getPointerTy(),
DAG.getConstant(0,
TLI.getPointerTy())),
Offset));
return 0;
}
case Intrinsic::convertff:
case Intrinsic::convertfsi:
case Intrinsic::convertfui:
case Intrinsic::convertsif:
case Intrinsic::convertuif:
case Intrinsic::convertss:
case Intrinsic::convertsu:
case Intrinsic::convertus:
case Intrinsic::convertuu: {
ISD::CvtCode Code = ISD::CVT_INVALID;
switch (Intrinsic) {
case Intrinsic::convertff: Code = ISD::CVT_FF; break;
case Intrinsic::convertfsi: Code = ISD::CVT_FS; break;
case Intrinsic::convertfui: Code = ISD::CVT_FU; break;
case Intrinsic::convertsif: Code = ISD::CVT_SF; break;
case Intrinsic::convertuif: Code = ISD::CVT_UF; break;
case Intrinsic::convertss: Code = ISD::CVT_SS; break;
case Intrinsic::convertsu: Code = ISD::CVT_SU; break;
case Intrinsic::convertus: Code = ISD::CVT_US; break;
case Intrinsic::convertuu: Code = ISD::CVT_UU; break;
}
MVT DestVT = TLI.getValueType(I.getType());
Value* Op1 = I.getOperand(1);
setValue(&I, DAG.getConvertRndSat(DestVT, getCurDebugLoc(), getValue(Op1),
DAG.getValueType(DestVT),
DAG.getValueType(getValue(Op1).getValueType()),
getValue(I.getOperand(2)),
getValue(I.getOperand(3)),
Code));
return 0;
}
case Intrinsic::sqrt:
setValue(&I, DAG.getNode(ISD::FSQRT, dl,
getValue(I.getOperand(1)).getValueType(),
getValue(I.getOperand(1))));
return 0;
case Intrinsic::powi:
setValue(&I, DAG.getNode(ISD::FPOWI, dl,
getValue(I.getOperand(1)).getValueType(),
getValue(I.getOperand(1)),
getValue(I.getOperand(2))));
return 0;
case Intrinsic::sin:
setValue(&I, DAG.getNode(ISD::FSIN, dl,
getValue(I.getOperand(1)).getValueType(),
getValue(I.getOperand(1))));
return 0;
case Intrinsic::cos:
setValue(&I, DAG.getNode(ISD::FCOS, dl,
getValue(I.getOperand(1)).getValueType(),
getValue(I.getOperand(1))));
return 0;
case Intrinsic::log:
visitLog(I);
return 0;
case Intrinsic::log2:
visitLog2(I);
return 0;
case Intrinsic::log10:
visitLog10(I);
return 0;
case Intrinsic::exp:
visitExp(I);
return 0;
case Intrinsic::exp2:
visitExp2(I);
return 0;
case Intrinsic::pow:
visitPow(I);
return 0;
case Intrinsic::pcmarker: {
SDValue Tmp = getValue(I.getOperand(1));
DAG.setRoot(DAG.getNode(ISD::PCMARKER, dl, MVT::Other, getRoot(), Tmp));
return 0;
}
case Intrinsic::readcyclecounter: {
SDValue Op = getRoot();
SDValue Tmp = DAG.getNode(ISD::READCYCLECOUNTER, dl,
DAG.getVTList(MVT::i64, MVT::Other),
&Op, 1);
setValue(&I, Tmp);
DAG.setRoot(Tmp.getValue(1));
return 0;
}
case Intrinsic::part_select: {
// Currently not implemented: just abort
assert(0 && "part_select intrinsic not implemented");
abort();
}
case Intrinsic::part_set: {
// Currently not implemented: just abort
assert(0 && "part_set intrinsic not implemented");
abort();
}
case Intrinsic::bswap:
setValue(&I, DAG.getNode(ISD::BSWAP, dl,
getValue(I.getOperand(1)).getValueType(),
getValue(I.getOperand(1))));
return 0;
case Intrinsic::cttz: {
SDValue Arg = getValue(I.getOperand(1));
MVT Ty = Arg.getValueType();
SDValue result = DAG.getNode(ISD::CTTZ, dl, Ty, Arg);
setValue(&I, result);
return 0;
}
case Intrinsic::ctlz: {
SDValue Arg = getValue(I.getOperand(1));
MVT Ty = Arg.getValueType();
SDValue result = DAG.getNode(ISD::CTLZ, dl, Ty, Arg);
setValue(&I, result);
return 0;
}
case Intrinsic::ctpop: {
SDValue Arg = getValue(I.getOperand(1));
MVT Ty = Arg.getValueType();
SDValue result = DAG.getNode(ISD::CTPOP, dl, Ty, Arg);
setValue(&I, result);
return 0;
}
case Intrinsic::stacksave: {
SDValue Op = getRoot();
SDValue Tmp = DAG.getNode(ISD::STACKSAVE, dl,
DAG.getVTList(TLI.getPointerTy(), MVT::Other), &Op, 1);
setValue(&I, Tmp);
DAG.setRoot(Tmp.getValue(1));
return 0;
}
case Intrinsic::stackrestore: {
SDValue Tmp = getValue(I.getOperand(1));
DAG.setRoot(DAG.getNode(ISD::STACKRESTORE, dl, MVT::Other, getRoot(), Tmp));
return 0;
}
case Intrinsic::stackprotector: {
// Emit code into the DAG to store the stack guard onto the stack.
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo *MFI = MF.getFrameInfo();
MVT PtrTy = TLI.getPointerTy();
SDValue Src = getValue(I.getOperand(1)); // The guard's value.
AllocaInst *Slot = cast<AllocaInst>(I.getOperand(2));
int FI = FuncInfo.StaticAllocaMap[Slot];
MFI->setStackProtectorIndex(FI);
SDValue FIN = DAG.getFrameIndex(FI, PtrTy);
// Store the stack protector onto the stack.
SDValue Result = DAG.getStore(getRoot(), getCurDebugLoc(), Src, FIN,
PseudoSourceValue::getFixedStack(FI),
0, true);
setValue(&I, Result);
DAG.setRoot(Result);
return 0;
}
case Intrinsic::var_annotation:
// Discard annotate attributes
return 0;
case Intrinsic::init_trampoline: {
const Function *F = cast<Function>(I.getOperand(2)->stripPointerCasts());
SDValue Ops[6];
Ops[0] = getRoot();
Ops[1] = getValue(I.getOperand(1));
Ops[2] = getValue(I.getOperand(2));
Ops[3] = getValue(I.getOperand(3));
Ops[4] = DAG.getSrcValue(I.getOperand(1));
Ops[5] = DAG.getSrcValue(F);
SDValue Tmp = DAG.getNode(ISD::TRAMPOLINE, dl,
DAG.getVTList(TLI.getPointerTy(), MVT::Other),
Ops, 6);
setValue(&I, Tmp);
DAG.setRoot(Tmp.getValue(1));
return 0;
}
case Intrinsic::gcroot:
if (GFI) {
Value *Alloca = I.getOperand(1);
Constant *TypeMap = cast<Constant>(I.getOperand(2));
FrameIndexSDNode *FI = cast<FrameIndexSDNode>(getValue(Alloca).getNode());
GFI->addStackRoot(FI->getIndex(), TypeMap);
}
return 0;
case Intrinsic::gcread:
case Intrinsic::gcwrite:
assert(0 && "GC failed to lower gcread/gcwrite intrinsics!");
return 0;
case Intrinsic::flt_rounds: {
setValue(&I, DAG.getNode(ISD::FLT_ROUNDS_, dl, MVT::i32));
return 0;
}
case Intrinsic::trap: {
DAG.setRoot(DAG.getNode(ISD::TRAP, dl,MVT::Other, getRoot()));
return 0;
}
case Intrinsic::uadd_with_overflow:
return implVisitAluOverflow(I, ISD::UADDO);
case Intrinsic::sadd_with_overflow:
return implVisitAluOverflow(I, ISD::SADDO);
case Intrinsic::usub_with_overflow:
return implVisitAluOverflow(I, ISD::USUBO);
case Intrinsic::ssub_with_overflow:
return implVisitAluOverflow(I, ISD::SSUBO);
case Intrinsic::umul_with_overflow:
return implVisitAluOverflow(I, ISD::UMULO);
case Intrinsic::smul_with_overflow:
return implVisitAluOverflow(I, ISD::SMULO);
case Intrinsic::prefetch: {
SDValue Ops[4];
Ops[0] = getRoot();
Ops[1] = getValue(I.getOperand(1));
Ops[2] = getValue(I.getOperand(2));
Ops[3] = getValue(I.getOperand(3));
DAG.setRoot(DAG.getNode(ISD::PREFETCH, dl, MVT::Other, &Ops[0], 4));
return 0;
}
case Intrinsic::memory_barrier: {
SDValue Ops[6];
Ops[0] = getRoot();
for (int x = 1; x < 6; ++x)
Ops[x] = getValue(I.getOperand(x));
DAG.setRoot(DAG.getNode(ISD::MEMBARRIER, dl, MVT::Other, &Ops[0], 6));
return 0;
}
case Intrinsic::atomic_cmp_swap: {
SDValue Root = getRoot();
SDValue L =
DAG.getAtomic(ISD::ATOMIC_CMP_SWAP, getCurDebugLoc(),
getValue(I.getOperand(2)).getValueType().getSimpleVT(),
Root,
getValue(I.getOperand(1)),
getValue(I.getOperand(2)),
getValue(I.getOperand(3)),
I.getOperand(1));
setValue(&I, L);
DAG.setRoot(L.getValue(1));
return 0;
}
case Intrinsic::atomic_load_add:
return implVisitBinaryAtomic(I, ISD::ATOMIC_LOAD_ADD);
case Intrinsic::atomic_load_sub:
return implVisitBinaryAtomic(I, ISD::ATOMIC_LOAD_SUB);
case Intrinsic::atomic_load_or:
return implVisitBinaryAtomic(I, ISD::ATOMIC_LOAD_OR);
case Intrinsic::atomic_load_xor:
return implVisitBinaryAtomic(I, ISD::ATOMIC_LOAD_XOR);
case Intrinsic::atomic_load_and:
return implVisitBinaryAtomic(I, ISD::ATOMIC_LOAD_AND);
case Intrinsic::atomic_load_nand:
return implVisitBinaryAtomic(I, ISD::ATOMIC_LOAD_NAND);
case Intrinsic::atomic_load_max:
return implVisitBinaryAtomic(I, ISD::ATOMIC_LOAD_MAX);
case Intrinsic::atomic_load_min:
return implVisitBinaryAtomic(I, ISD::ATOMIC_LOAD_MIN);
case Intrinsic::atomic_load_umin:
return implVisitBinaryAtomic(I, ISD::ATOMIC_LOAD_UMIN);
case Intrinsic::atomic_load_umax:
return implVisitBinaryAtomic(I, ISD::ATOMIC_LOAD_UMAX);
case Intrinsic::atomic_swap:
return implVisitBinaryAtomic(I, ISD::ATOMIC_SWAP);
}
}
void SelectionDAGLowering::LowerCallTo(CallSite CS, SDValue Callee,
bool IsTailCall,
MachineBasicBlock *LandingPad) {
const PointerType *PT = cast<PointerType>(CS.getCalledValue()->getType());
const FunctionType *FTy = cast<FunctionType>(PT->getElementType());
MachineModuleInfo *MMI = DAG.getMachineModuleInfo();
unsigned BeginLabel = 0, EndLabel = 0;
TargetLowering::ArgListTy Args;
TargetLowering::ArgListEntry Entry;
Args.reserve(CS.arg_size());
for (CallSite::arg_iterator i = CS.arg_begin(), e = CS.arg_end();
i != e; ++i) {
SDValue ArgNode = getValue(*i);
Entry.Node = ArgNode; Entry.Ty = (*i)->getType();
unsigned attrInd = i - CS.arg_begin() + 1;
Entry.isSExt = CS.paramHasAttr(attrInd, Attribute::SExt);
Entry.isZExt = CS.paramHasAttr(attrInd, Attribute::ZExt);
Entry.isInReg = CS.paramHasAttr(attrInd, Attribute::InReg);
Entry.isSRet = CS.paramHasAttr(attrInd, Attribute::StructRet);
Entry.isNest = CS.paramHasAttr(attrInd, Attribute::Nest);
Entry.isByVal = CS.paramHasAttr(attrInd, Attribute::ByVal);
Entry.Alignment = CS.getParamAlignment(attrInd);
Args.push_back(Entry);
}
if (LandingPad && MMI) {
// Insert a label before the invoke call to mark the try range. This can be
// used to detect deletion of the invoke via the MachineModuleInfo.
BeginLabel = MMI->NextLabelID();
// Both PendingLoads and PendingExports must be flushed here;
// this call might not return.
(void)getRoot();
DAG.setRoot(DAG.getLabel(ISD::EH_LABEL, getCurDebugLoc(),
getControlRoot(), BeginLabel));
}
std::pair<SDValue,SDValue> Result =
TLI.LowerCallTo(getRoot(), CS.getType(),
CS.paramHasAttr(0, Attribute::SExt),
CS.paramHasAttr(0, Attribute::ZExt), FTy->isVarArg(),
CS.paramHasAttr(0, Attribute::InReg),
CS.getCallingConv(),
IsTailCall && PerformTailCallOpt,
Callee, Args, DAG, getCurDebugLoc());
if (CS.getType() != Type::VoidTy)
setValue(CS.getInstruction(), Result.first);
DAG.setRoot(Result.second);
if (LandingPad && MMI) {
// Insert a label at the end of the invoke call to mark the try range. This
// can be used to detect deletion of the invoke via the MachineModuleInfo.
EndLabel = MMI->NextLabelID();
DAG.setRoot(DAG.getLabel(ISD::EH_LABEL, getCurDebugLoc(),
getRoot(), EndLabel));
// Inform MachineModuleInfo of range.
MMI->addInvoke(LandingPad, BeginLabel, EndLabel);
}
}
void SelectionDAGLowering::visitCall(CallInst &I) {
const char *RenameFn = 0;
if (Function *F = I.getCalledFunction()) {
if (F->isDeclaration()) {
const TargetIntrinsicInfo *II = TLI.getTargetMachine().getIntrinsicInfo();
if (II) {
if (unsigned IID = II->getIntrinsicID(F)) {
RenameFn = visitIntrinsicCall(I, IID);
if (!RenameFn)
return;
}
}
if (unsigned IID = F->getIntrinsicID()) {
RenameFn = visitIntrinsicCall(I, IID);
if (!RenameFn)
return;
}
}
// Check for well-known libc/libm calls. If the function is internal, it
// can't be a library call.
unsigned NameLen = F->getNameLen();
if (!F->hasLocalLinkage() && NameLen) {
const char *NameStr = F->getNameStart();
if (NameStr[0] == 'c' &&
((NameLen == 8 && !strcmp(NameStr, "copysign")) ||
(NameLen == 9 && !strcmp(NameStr, "copysignf")))) {
if (I.getNumOperands() == 3 && // Basic sanity checks.
I.getOperand(1)->getType()->isFloatingPoint() &&
I.getType() == I.getOperand(1)->getType() &&
I.getType() == I.getOperand(2)->getType()) {
SDValue LHS = getValue(I.getOperand(1));
SDValue RHS = getValue(I.getOperand(2));
setValue(&I, DAG.getNode(ISD::FCOPYSIGN, getCurDebugLoc(),
LHS.getValueType(), LHS, RHS));
return;
}
} else if (NameStr[0] == 'f' &&
((NameLen == 4 && !strcmp(NameStr, "fabs")) ||
(NameLen == 5 && !strcmp(NameStr, "fabsf")) ||
(NameLen == 5 && !strcmp(NameStr, "fabsl")))) {
if (I.getNumOperands() == 2 && // Basic sanity checks.
I.getOperand(1)->getType()->isFloatingPoint() &&
I.getType() == I.getOperand(1)->getType()) {
SDValue Tmp = getValue(I.getOperand(1));
setValue(&I, DAG.getNode(ISD::FABS, getCurDebugLoc(),
Tmp.getValueType(), Tmp));
return;
}
} else if (NameStr[0] == 's' &&
((NameLen == 3 && !strcmp(NameStr, "sin")) ||
(NameLen == 4 && !strcmp(NameStr, "sinf")) ||
(NameLen == 4 && !strcmp(NameStr, "sinl")))) {
if (I.getNumOperands() == 2 && // Basic sanity checks.
I.getOperand(1)->getType()->isFloatingPoint() &&
I.getType() == I.getOperand(1)->getType()) {
SDValue Tmp = getValue(I.getOperand(1));
setValue(&I, DAG.getNode(ISD::FSIN, getCurDebugLoc(),
Tmp.getValueType(), Tmp));
return;
}
} else if (NameStr[0] == 'c' &&
((NameLen == 3 && !strcmp(NameStr, "cos")) ||
(NameLen == 4 && !strcmp(NameStr, "cosf")) ||
(NameLen == 4 && !strcmp(NameStr, "cosl")))) {
if (I.getNumOperands() == 2 && // Basic sanity checks.
I.getOperand(1)->getType()->isFloatingPoint() &&
I.getType() == I.getOperand(1)->getType()) {
SDValue Tmp = getValue(I.getOperand(1));
setValue(&I, DAG.getNode(ISD::FCOS, getCurDebugLoc(),
Tmp.getValueType(), Tmp));
return;
}
}
}
} else if (isa<InlineAsm>(I.getOperand(0))) {
visitInlineAsm(&I);
return;
}
SDValue Callee;
if (!RenameFn)
Callee = getValue(I.getOperand(0));
else
Callee = DAG.getExternalSymbol(RenameFn, TLI.getPointerTy());
LowerCallTo(&I, Callee, I.isTailCall());
}
/// getCopyFromRegs - Emit a series of CopyFromReg nodes that copies from
/// this value and returns the result as a ValueVT value. This uses
/// Chain/Flag as the input and updates them for the output Chain/Flag.
/// If the Flag pointer is NULL, no flag is used.
SDValue RegsForValue::getCopyFromRegs(SelectionDAG &DAG, DebugLoc dl,
SDValue &Chain,
SDValue *Flag) const {
// Assemble the legal parts into the final values.
SmallVector<SDValue, 4> Values(ValueVTs.size());
SmallVector<SDValue, 8> Parts;
for (unsigned Value = 0, Part = 0, e = ValueVTs.size(); Value != e; ++Value) {
// Copy the legal parts from the registers.
MVT ValueVT = ValueVTs[Value];
unsigned NumRegs = TLI->getNumRegisters(ValueVT);
MVT RegisterVT = RegVTs[Value];
Parts.resize(NumRegs);
for (unsigned i = 0; i != NumRegs; ++i) {
SDValue P;
if (Flag == 0)
P = DAG.getCopyFromReg(Chain, dl, Regs[Part+i], RegisterVT);
else {
P = DAG.getCopyFromReg(Chain, dl, Regs[Part+i], RegisterVT, *Flag);
*Flag = P.getValue(2);
}
Chain = P.getValue(1);
// If the source register was virtual and if we know something about it,
// add an assert node.
if (TargetRegisterInfo::isVirtualRegister(Regs[Part+i]) &&
RegisterVT.isInteger() && !RegisterVT.isVector()) {
unsigned SlotNo = Regs[Part+i]-TargetRegisterInfo::FirstVirtualRegister;
FunctionLoweringInfo &FLI = DAG.getFunctionLoweringInfo();
if (FLI.LiveOutRegInfo.size() > SlotNo) {
FunctionLoweringInfo::LiveOutInfo &LOI = FLI.LiveOutRegInfo[SlotNo];
unsigned RegSize = RegisterVT.getSizeInBits();
unsigned NumSignBits = LOI.NumSignBits;
unsigned NumZeroBits = LOI.KnownZero.countLeadingOnes();
// FIXME: We capture more information than the dag can represent. For
// now, just use the tightest assertzext/assertsext possible.
bool isSExt = true;
MVT FromVT(MVT::Other);
if (NumSignBits == RegSize)
isSExt = true, FromVT = MVT::i1; // ASSERT SEXT 1
else if (NumZeroBits >= RegSize-1)
isSExt = false, FromVT = MVT::i1; // ASSERT ZEXT 1
else if (NumSignBits > RegSize-8)
isSExt = true, FromVT = MVT::i8; // ASSERT SEXT 8
else if (NumZeroBits >= RegSize-8)
isSExt = false, FromVT = MVT::i8; // ASSERT ZEXT 8
else if (NumSignBits > RegSize-16)
isSExt = true, FromVT = MVT::i16; // ASSERT SEXT 16
else if (NumZeroBits >= RegSize-16)
isSExt = false, FromVT = MVT::i16; // ASSERT ZEXT 16
else if (NumSignBits > RegSize-32)
isSExt = true, FromVT = MVT::i32; // ASSERT SEXT 32
else if (NumZeroBits >= RegSize-32)
isSExt = false, FromVT = MVT::i32; // ASSERT ZEXT 32
if (FromVT != MVT::Other) {
P = DAG.getNode(isSExt ? ISD::AssertSext : ISD::AssertZext, dl,
RegisterVT, P, DAG.getValueType(FromVT));
}
}
}
Parts[i] = P;
}
Values[Value] = getCopyFromParts(DAG, dl, Parts.begin(),
NumRegs, RegisterVT, ValueVT);
Part += NumRegs;
Parts.clear();
}
return DAG.getNode(ISD::MERGE_VALUES, dl,
DAG.getVTList(&ValueVTs[0], ValueVTs.size()),
&Values[0], ValueVTs.size());
}
/// getCopyToRegs - Emit a series of CopyToReg nodes that copies the
/// specified value into the registers specified by this object. This uses
/// Chain/Flag as the input and updates them for the output Chain/Flag.
/// If the Flag pointer is NULL, no flag is used.
void RegsForValue::getCopyToRegs(SDValue Val, SelectionDAG &DAG, DebugLoc dl,
SDValue &Chain, SDValue *Flag) const {
// Get the list of the values's legal parts.
unsigned NumRegs = Regs.size();
SmallVector<SDValue, 8> Parts(NumRegs);
for (unsigned Value = 0, Part = 0, e = ValueVTs.size(); Value != e; ++Value) {
MVT ValueVT = ValueVTs[Value];
unsigned NumParts = TLI->getNumRegisters(ValueVT);
MVT RegisterVT = RegVTs[Value];
getCopyToParts(DAG, dl, Val.getValue(Val.getResNo() + Value),
&Parts[Part], NumParts, RegisterVT);
Part += NumParts;
}
// Copy the parts into the registers.
SmallVector<SDValue, 8> Chains(NumRegs);
for (unsigned i = 0; i != NumRegs; ++i) {
SDValue Part;
if (Flag == 0)
Part = DAG.getCopyToReg(Chain, dl, Regs[i], Parts[i]);
else {
Part = DAG.getCopyToReg(Chain, dl, Regs[i], Parts[i], *Flag);
*Flag = Part.getValue(1);
}
Chains[i] = Part.getValue(0);
}
if (NumRegs == 1 || Flag)
// If NumRegs > 1 && Flag is used then the use of the last CopyToReg is
// flagged to it. That is the CopyToReg nodes and the user are considered
// a single scheduling unit. If we create a TokenFactor and return it as
// chain, then the TokenFactor is both a predecessor (operand) of the
// user as well as a successor (the TF operands are flagged to the user).
// c1, f1 = CopyToReg
// c2, f2 = CopyToReg
// c3 = TokenFactor c1, c2
// ...
// = op c3, ..., f2
Chain = Chains[NumRegs-1];
else
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &Chains[0], NumRegs);
}
/// AddInlineAsmOperands - Add this value to the specified inlineasm node
/// operand list. This adds the code marker and includes the number of
/// values added into it.
void RegsForValue::AddInlineAsmOperands(unsigned Code,
bool HasMatching,unsigned MatchingIdx,
SelectionDAG &DAG,
std::vector<SDValue> &Ops) const {
MVT IntPtrTy = DAG.getTargetLoweringInfo().getPointerTy();
assert(Regs.size() < (1 << 13) && "Too many inline asm outputs!");
unsigned Flag = Code | (Regs.size() << 3);
if (HasMatching)
Flag |= 0x80000000 | (MatchingIdx << 16);
Ops.push_back(DAG.getTargetConstant(Flag, IntPtrTy));
for (unsigned Value = 0, Reg = 0, e = ValueVTs.size(); Value != e; ++Value) {
unsigned NumRegs = TLI->getNumRegisters(ValueVTs[Value]);
MVT RegisterVT = RegVTs[Value];
for (unsigned i = 0; i != NumRegs; ++i) {
assert(Reg < Regs.size() && "Mismatch in # registers expected");
Ops.push_back(DAG.getRegister(Regs[Reg++], RegisterVT));
}
}
}
/// isAllocatableRegister - If the specified register is safe to allocate,
/// i.e. it isn't a stack pointer or some other special register, return the
/// register class for the register. Otherwise, return null.
static const TargetRegisterClass *
isAllocatableRegister(unsigned Reg, MachineFunction &MF,
const TargetLowering &TLI,
const TargetRegisterInfo *TRI) {
MVT FoundVT = MVT::Other;
const TargetRegisterClass *FoundRC = 0;
for (TargetRegisterInfo::regclass_iterator RCI = TRI->regclass_begin(),
E = TRI->regclass_end(); RCI != E; ++RCI) {
MVT ThisVT = MVT::Other;
const TargetRegisterClass *RC = *RCI;
// If none of the the value types for this register class are valid, we
// can't use it. For example, 64-bit reg classes on 32-bit targets.
for (TargetRegisterClass::vt_iterator I = RC->vt_begin(), E = RC->vt_end();
I != E; ++I) {
if (TLI.isTypeLegal(*I)) {
// If we have already found this register in a different register class,
// choose the one with the largest VT specified. For example, on
// PowerPC, we favor f64 register classes over f32.
if (FoundVT == MVT::Other || FoundVT.bitsLT(*I)) {
ThisVT = *I;
break;
}
}
}
if (ThisVT == MVT::Other) continue;
// NOTE: This isn't ideal. In particular, this might allocate the
// frame pointer in functions that need it (due to them not being taken
// out of allocation, because a variable sized allocation hasn't been seen
// yet). This is a slight code pessimization, but should still work.
for (TargetRegisterClass::iterator I = RC->allocation_order_begin(MF),
E = RC->allocation_order_end(MF); I != E; ++I)
if (*I == Reg) {
// We found a matching register class. Keep looking at others in case
// we find one with larger registers that this physreg is also in.
FoundRC = RC;
FoundVT = ThisVT;
break;
}
}
return FoundRC;
}
namespace llvm {
/// AsmOperandInfo - This contains information for each constraint that we are
/// lowering.
class VISIBILITY_HIDDEN SDISelAsmOperandInfo :
public TargetLowering::AsmOperandInfo {
public:
/// CallOperand - If this is the result output operand or a clobber
/// this is null, otherwise it is the incoming operand to the CallInst.
/// This gets modified as the asm is processed.
SDValue CallOperand;
/// AssignedRegs - If this is a register or register class operand, this
/// contains the set of register corresponding to the operand.
RegsForValue AssignedRegs;
explicit SDISelAsmOperandInfo(const InlineAsm::ConstraintInfo &info)
: TargetLowering::AsmOperandInfo(info), CallOperand(0,0) {
}
/// MarkAllocatedRegs - Once AssignedRegs is set, mark the assigned registers
/// busy in OutputRegs/InputRegs.
void MarkAllocatedRegs(bool isOutReg, bool isInReg,
std::set<unsigned> &OutputRegs,
std::set<unsigned> &InputRegs,
const TargetRegisterInfo &TRI) const {
if (isOutReg) {
for (unsigned i = 0, e = AssignedRegs.Regs.size(); i != e; ++i)
MarkRegAndAliases(AssignedRegs.Regs[i], OutputRegs, TRI);
}
if (isInReg) {
for (unsigned i = 0, e = AssignedRegs.Regs.size(); i != e; ++i)
MarkRegAndAliases(AssignedRegs.Regs[i], InputRegs, TRI);
}
}
/// getCallOperandValMVT - Return the MVT of the Value* that this operand
/// corresponds to. If there is no Value* for this operand, it returns
/// MVT::Other.
MVT getCallOperandValMVT(const TargetLowering &TLI,
const TargetData *TD) const {
if (CallOperandVal == 0) return MVT::Other;
if (isa<BasicBlock>(CallOperandVal))
return TLI.getPointerTy();
const llvm::Type *OpTy = CallOperandVal->getType();
// If this is an indirect operand, the operand is a pointer to the
// accessed type.
if (isIndirect)
OpTy = cast<PointerType>(OpTy)->getElementType();
// If OpTy is not a single value, it may be a struct/union that we
// can tile with integers.
if (!OpTy->isSingleValueType() && OpTy->isSized()) {
unsigned BitSize = TD->getTypeSizeInBits(OpTy);
switch (BitSize) {
default: break;
case 1:
case 8:
case 16:
case 32:
case 64:
case 128:
OpTy = IntegerType::get(BitSize);
break;
}
}
return TLI.getValueType(OpTy, true);
}
private:
/// MarkRegAndAliases - Mark the specified register and all aliases in the
/// specified set.
static void MarkRegAndAliases(unsigned Reg, std::set<unsigned> &Regs,
const TargetRegisterInfo &TRI) {
assert(TargetRegisterInfo::isPhysicalRegister(Reg) && "Isn't a physreg");
Regs.insert(Reg);
if (const unsigned *Aliases = TRI.getAliasSet(Reg))
for (; *Aliases; ++Aliases)
Regs.insert(*Aliases);
}
};
} // end llvm namespace.
/// GetRegistersForValue - Assign registers (virtual or physical) for the
/// specified operand. We prefer to assign virtual registers, to allow the
/// register allocator handle the assignment process. However, if the asm uses
/// features that we can't model on machineinstrs, we have SDISel do the
/// allocation. This produces generally horrible, but correct, code.
///
/// OpInfo describes the operand.
/// Input and OutputRegs are the set of already allocated physical registers.
///
void SelectionDAGLowering::
GetRegistersForValue(SDISelAsmOperandInfo &OpInfo,
std::set<unsigned> &OutputRegs,
std::set<unsigned> &InputRegs) {
// Compute whether this value requires an input register, an output register,
// or both.
bool isOutReg = false;
bool isInReg = false;
switch (OpInfo.Type) {
case InlineAsm::isOutput:
isOutReg = true;
// If there is an input constraint that matches this, we need to reserve
// the input register so no other inputs allocate to it.
isInReg = OpInfo.hasMatchingInput();
break;
case InlineAsm::isInput:
isInReg = true;
isOutReg = false;
break;
case InlineAsm::isClobber:
isOutReg = true;
isInReg = true;
break;
}
MachineFunction &MF = DAG.getMachineFunction();
SmallVector<unsigned, 4> Regs;
// If this is a constraint for a single physreg, or a constraint for a
// register class, find it.
std::pair<unsigned, const TargetRegisterClass*> PhysReg =
TLI.getRegForInlineAsmConstraint(OpInfo.ConstraintCode,
OpInfo.ConstraintVT);
unsigned NumRegs = 1;
if (OpInfo.ConstraintVT != MVT::Other) {
// If this is a FP input in an integer register (or visa versa) insert a bit
// cast of the input value. More generally, handle any case where the input
// value disagrees with the register class we plan to stick this in.
if (OpInfo.Type == InlineAsm::isInput &&
PhysReg.second && !PhysReg.second->hasType(OpInfo.ConstraintVT)) {
// Try to convert to the first MVT that the reg class contains. If the
// types are identical size, use a bitcast to convert (e.g. two differing
// vector types).
MVT RegVT = *PhysReg.second->vt_begin();
if (RegVT.getSizeInBits() == OpInfo.ConstraintVT.getSizeInBits()) {
OpInfo.CallOperand = DAG.getNode(ISD::BIT_CONVERT, getCurDebugLoc(),
RegVT, OpInfo.CallOperand);
OpInfo.ConstraintVT = RegVT;
} else if (RegVT.isInteger() && OpInfo.ConstraintVT.isFloatingPoint()) {
// If the input is a FP value and we want it in FP registers, do a
// bitcast to the corresponding integer type. This turns an f64 value
// into i64, which can be passed with two i32 values on a 32-bit
// machine.
RegVT = MVT::getIntegerVT(OpInfo.ConstraintVT.getSizeInBits());
OpInfo.CallOperand = DAG.getNode(ISD::BIT_CONVERT, getCurDebugLoc(),
RegVT, OpInfo.CallOperand);
OpInfo.ConstraintVT = RegVT;
}
}
NumRegs = TLI.getNumRegisters(OpInfo.ConstraintVT);
}
MVT RegVT;
MVT ValueVT = OpInfo.ConstraintVT;
// If this is a constraint for a specific physical register, like {r17},
// assign it now.
if (unsigned AssignedReg = PhysReg.first) {
const TargetRegisterClass *RC = PhysReg.second;
if (OpInfo.ConstraintVT == MVT::Other)
ValueVT = *RC->vt_begin();
// Get the actual register value type. This is important, because the user
// may have asked for (e.g.) the AX register in i32 type. We need to
// remember that AX is actually i16 to get the right extension.
RegVT = *RC->vt_begin();
// This is a explicit reference to a physical register.
Regs.push_back(AssignedReg);
// If this is an expanded reference, add the rest of the regs to Regs.
if (NumRegs != 1) {
TargetRegisterClass::iterator I = RC->begin();
for (; *I != AssignedReg; ++I)
assert(I != RC->end() && "Didn't find reg!");
// Already added the first reg.
--NumRegs; ++I;
for (; NumRegs; --NumRegs, ++I) {
assert(I != RC->end() && "Ran out of registers to allocate!");
Regs.push_back(*I);
}
}
OpInfo.AssignedRegs = RegsForValue(TLI, Regs, RegVT, ValueVT);
const TargetRegisterInfo *TRI = DAG.getTarget().getRegisterInfo();
OpInfo.MarkAllocatedRegs(isOutReg, isInReg, OutputRegs, InputRegs, *TRI);
return;
}
// Otherwise, if this was a reference to an LLVM register class, create vregs
// for this reference.
if (const TargetRegisterClass *RC = PhysReg.second) {
RegVT = *RC->vt_begin();
if (OpInfo.ConstraintVT == MVT::Other)
ValueVT = RegVT;
// Create the appropriate number of virtual registers.
MachineRegisterInfo &RegInfo = MF.getRegInfo();
for (; NumRegs; --NumRegs)
Regs.push_back(RegInfo.createVirtualRegister(RC));
OpInfo.AssignedRegs = RegsForValue(TLI, Regs, RegVT, ValueVT);
return;
}
// This is a reference to a register class that doesn't directly correspond
// to an LLVM register class. Allocate NumRegs consecutive, available,
// registers from the class.
std::vector<unsigned> RegClassRegs
= TLI.getRegClassForInlineAsmConstraint(OpInfo.ConstraintCode,
OpInfo.ConstraintVT);
const TargetRegisterInfo *TRI = DAG.getTarget().getRegisterInfo();
unsigned NumAllocated = 0;
for (unsigned i = 0, e = RegClassRegs.size(); i != e; ++i) {
unsigned Reg = RegClassRegs[i];
// See if this register is available.
if ((isOutReg && OutputRegs.count(Reg)) || // Already used.
(isInReg && InputRegs.count(Reg))) { // Already used.
// Make sure we find consecutive registers.
NumAllocated = 0;
continue;
}
// Check to see if this register is allocatable (i.e. don't give out the
// stack pointer).
const TargetRegisterClass *RC = isAllocatableRegister(Reg, MF, TLI, TRI);
if (!RC) { // Couldn't allocate this register.
// Reset NumAllocated to make sure we return consecutive registers.
NumAllocated = 0;
continue;
}
// Okay, this register is good, we can use it.
++NumAllocated;
// If we allocated enough consecutive registers, succeed.
if (NumAllocated == NumRegs) {
unsigned RegStart = (i-NumAllocated)+1;
unsigned RegEnd = i+1;
// Mark all of the allocated registers used.
for (unsigned i = RegStart; i != RegEnd; ++i)
Regs.push_back(RegClassRegs[i]);
OpInfo.AssignedRegs = RegsForValue(TLI, Regs, *RC->vt_begin(),
OpInfo.ConstraintVT);
OpInfo.MarkAllocatedRegs(isOutReg, isInReg, OutputRegs, InputRegs, *TRI);
return;
}
}
// Otherwise, we couldn't allocate enough registers for this.
}
/// hasInlineAsmMemConstraint - Return true if the inline asm instruction being
/// processed uses a memory 'm' constraint.
static bool
hasInlineAsmMemConstraint(std::vector<InlineAsm::ConstraintInfo> &CInfos,
const TargetLowering &TLI) {
for (unsigned i = 0, e = CInfos.size(); i != e; ++i) {
InlineAsm::ConstraintInfo &CI = CInfos[i];
for (unsigned j = 0, ee = CI.Codes.size(); j != ee; ++j) {
TargetLowering::ConstraintType CType = TLI.getConstraintType(CI.Codes[j]);
if (CType == TargetLowering::C_Memory)
return true;
}
// Indirect operand accesses access memory.
if (CI.isIndirect)
return true;
}
return false;
}
/// visitInlineAsm - Handle a call to an InlineAsm object.
///
void SelectionDAGLowering::visitInlineAsm(CallSite CS) {
InlineAsm *IA = cast<InlineAsm>(CS.getCalledValue());
/// ConstraintOperands - Information about all of the constraints.
std::vector<SDISelAsmOperandInfo> ConstraintOperands;
std::set<unsigned> OutputRegs, InputRegs;
// Do a prepass over the constraints, canonicalizing them, and building up the
// ConstraintOperands list.
std::vector<InlineAsm::ConstraintInfo>
ConstraintInfos = IA->ParseConstraints();
bool hasMemory = hasInlineAsmMemConstraint(ConstraintInfos, TLI);
SDValue Chain, Flag;
// We won't need to flush pending loads if this asm doesn't touch
// memory and is nonvolatile.
if (hasMemory || IA->hasSideEffects())
Chain = getRoot();
else
Chain = DAG.getRoot();
unsigned ArgNo = 0; // ArgNo - The argument of the CallInst.
unsigned ResNo = 0; // ResNo - The result number of the next output.
for (unsigned i = 0, e = ConstraintInfos.size(); i != e; ++i) {
ConstraintOperands.push_back(SDISelAsmOperandInfo(ConstraintInfos[i]));
SDISelAsmOperandInfo &OpInfo = ConstraintOperands.back();
MVT OpVT = MVT::Other;
// Compute the value type for each operand.
switch (OpInfo.Type) {
case InlineAsm::isOutput:
// Indirect outputs just consume an argument.
if (OpInfo.isIndirect) {
OpInfo.CallOperandVal = CS.getArgument(ArgNo++);
break;
}
// The return value of the call is this value. As such, there is no
// corresponding argument.
assert(CS.getType() != Type::VoidTy && "Bad inline asm!");
if (const StructType *STy = dyn_cast<StructType>(CS.getType())) {
OpVT = TLI.getValueType(STy->getElementType(ResNo));
} else {
assert(ResNo == 0 && "Asm only has one result!");
OpVT = TLI.getValueType(CS.getType());
}
++ResNo;
break;
case InlineAsm::isInput:
OpInfo.CallOperandVal = CS.getArgument(ArgNo++);
break;
case InlineAsm::isClobber:
// Nothing to do.
break;
}
// If this is an input or an indirect output, process the call argument.
// BasicBlocks are labels, currently appearing only in asm's.
if (OpInfo.CallOperandVal) {
if (BasicBlock *BB = dyn_cast<BasicBlock>(OpInfo.CallOperandVal)) {
OpInfo.CallOperand = DAG.getBasicBlock(FuncInfo.MBBMap[BB]);
} else {
OpInfo.CallOperand = getValue(OpInfo.CallOperandVal);
}
OpVT = OpInfo.getCallOperandValMVT(TLI, TD);
}
OpInfo.ConstraintVT = OpVT;
}
// Second pass over the constraints: compute which constraint option to use
// and assign registers to constraints that want a specific physreg.
for (unsigned i = 0, e = ConstraintInfos.size(); i != e; ++i) {
SDISelAsmOperandInfo &OpInfo = ConstraintOperands[i];
// If this is an output operand with a matching input operand, look up the
// matching input. If their types mismatch, e.g. one is an integer, the
// other is floating point, or their sizes are different, flag it as an
// error.
if (OpInfo.hasMatchingInput()) {
SDISelAsmOperandInfo &Input = ConstraintOperands[OpInfo.MatchingInput];
if (OpInfo.ConstraintVT != Input.ConstraintVT) {
if ((OpInfo.ConstraintVT.isInteger() !=
Input.ConstraintVT.isInteger()) ||
(OpInfo.ConstraintVT.getSizeInBits() !=
Input.ConstraintVT.getSizeInBits())) {
cerr << "llvm: error: Unsupported asm: input constraint with a "
<< "matching output constraint of incompatible type!\n";
exit(1);
}
Input.ConstraintVT = OpInfo.ConstraintVT;
}
}
// Compute the constraint code and ConstraintType to use.
TLI.ComputeConstraintToUse(OpInfo, OpInfo.CallOperand, hasMemory, &DAG);
// If this is a memory input, and if the operand is not indirect, do what we
// need to to provide an address for the memory input.
if (OpInfo.ConstraintType == TargetLowering::C_Memory &&
!OpInfo.isIndirect) {
assert(OpInfo.Type == InlineAsm::isInput &&
"Can only indirectify direct input operands!");
// Memory operands really want the address of the value. If we don't have
// an indirect input, put it in the constpool if we can, otherwise spill
// it to a stack slot.
// If the operand is a float, integer, or vector constant, spill to a
// constant pool entry to get its address.
Value *OpVal = OpInfo.CallOperandVal;
if (isa<ConstantFP>(OpVal) || isa<ConstantInt>(OpVal) ||
isa<ConstantVector>(OpVal)) {
OpInfo.CallOperand = DAG.getConstantPool(cast<Constant>(OpVal),
TLI.getPointerTy());
} else {
// Otherwise, create a stack slot and emit a store to it before the
// asm.
const Type *Ty = OpVal->getType();
uint64_t TySize = TLI.getTargetData()->getTypeAllocSize(Ty);
unsigned Align = TLI.getTargetData()->getPrefTypeAlignment(Ty);
MachineFunction &MF = DAG.getMachineFunction();
int SSFI = MF.getFrameInfo()->CreateStackObject(TySize, Align);
SDValue StackSlot = DAG.getFrameIndex(SSFI, TLI.getPointerTy());
Chain = DAG.getStore(Chain, getCurDebugLoc(),
OpInfo.CallOperand, StackSlot, NULL, 0);
OpInfo.CallOperand = StackSlot;
}
// There is no longer a Value* corresponding to this operand.
OpInfo.CallOperandVal = 0;
// It is now an indirect operand.
OpInfo.isIndirect = true;
}
// If this constraint is for a specific register, allocate it before
// anything else.
if (OpInfo.ConstraintType == TargetLowering::C_Register)
GetRegistersForValue(OpInfo, OutputRegs, InputRegs);
}
ConstraintInfos.clear();
// Second pass - Loop over all of the operands, assigning virtual or physregs
// to register class operands.
for (unsigned i = 0, e = ConstraintOperands.size(); i != e; ++i) {
SDISelAsmOperandInfo &OpInfo = ConstraintOperands[i];
// C_Register operands have already been allocated, Other/Memory don't need
// to be.
if (OpInfo.ConstraintType == TargetLowering::C_RegisterClass)
GetRegistersForValue(OpInfo, OutputRegs, InputRegs);
}
// AsmNodeOperands - The operands for the ISD::INLINEASM node.
std::vector<SDValue> AsmNodeOperands;
AsmNodeOperands.push_back(SDValue()); // reserve space for input chain
AsmNodeOperands.push_back(
DAG.getTargetExternalSymbol(IA->getAsmString().c_str(), MVT::Other));
// Loop over all of the inputs, copying the operand values into the
// appropriate registers and processing the output regs.
RegsForValue RetValRegs;
// IndirectStoresToEmit - The set of stores to emit after the inline asm node.
std::vector<std::pair<RegsForValue, Value*> > IndirectStoresToEmit;
for (unsigned i = 0, e = ConstraintOperands.size(); i != e; ++i) {
SDISelAsmOperandInfo &OpInfo = ConstraintOperands[i];
switch (OpInfo.Type) {
case InlineAsm::isOutput: {
if (OpInfo.ConstraintType != TargetLowering::C_RegisterClass &&
OpInfo.ConstraintType != TargetLowering::C_Register) {
// Memory output, or 'other' output (e.g. 'X' constraint).
assert(OpInfo.isIndirect && "Memory output must be indirect operand");
// Add information to the INLINEASM node to know about this output.
unsigned ResOpType = 4/*MEM*/ | (1<<3);
AsmNodeOperands.push_back(DAG.getTargetConstant(ResOpType,
TLI.getPointerTy()));
AsmNodeOperands.push_back(OpInfo.CallOperand);
break;
}
// Otherwise, this is a register or register class output.
// Copy the output from the appropriate register. Find a register that
// we can use.
if (OpInfo.AssignedRegs.Regs.empty()) {
cerr << "llvm: error: Couldn't allocate output reg for constraint '"
<< OpInfo.ConstraintCode << "'!\n";
exit(1);
}
// If this is an indirect operand, store through the pointer after the
// asm.
if (OpInfo.isIndirect) {
IndirectStoresToEmit.push_back(std::make_pair(OpInfo.AssignedRegs,
OpInfo.CallOperandVal));
} else {
// This is the result value of the call.
assert(CS.getType() != Type::VoidTy && "Bad inline asm!");
// Concatenate this output onto the outputs list.
RetValRegs.append(OpInfo.AssignedRegs);
}
// Add information to the INLINEASM node to know that this register is
// set.
OpInfo.AssignedRegs.AddInlineAsmOperands(OpInfo.isEarlyClobber ?
6 /* EARLYCLOBBER REGDEF */ :
2 /* REGDEF */ ,
false,
0,
DAG, AsmNodeOperands);
break;
}
case InlineAsm::isInput: {
SDValue InOperandVal = OpInfo.CallOperand;
if (OpInfo.isMatchingInputConstraint()) { // Matching constraint?
// If this is required to match an output register we have already set,
// just use its register.
unsigned OperandNo = OpInfo.getMatchedOperand();
// Scan until we find the definition we already emitted of this operand.
// When we find it, create a RegsForValue operand.
unsigned CurOp = 2; // The first operand.
for (; OperandNo; --OperandNo) {
// Advance to the next operand.
unsigned OpFlag =
cast<ConstantSDNode>(AsmNodeOperands[CurOp])->getZExtValue();
assert(((OpFlag & 7) == 2 /*REGDEF*/ ||
(OpFlag & 7) == 6 /*EARLYCLOBBER REGDEF*/ ||
(OpFlag & 7) == 4 /*MEM*/) &&
"Skipped past definitions?");
CurOp += InlineAsm::getNumOperandRegisters(OpFlag)+1;
}
unsigned OpFlag =
cast<ConstantSDNode>(AsmNodeOperands[CurOp])->getZExtValue();
if ((OpFlag & 7) == 2 /*REGDEF*/
|| (OpFlag & 7) == 6 /* EARLYCLOBBER REGDEF */) {
// Add (OpFlag&0xffff)>>3 registers to MatchedRegs.
assert(!OpInfo.isIndirect &&
"Don't know how to handle tied indirect register inputs yet!");
RegsForValue MatchedRegs;
MatchedRegs.TLI = &TLI;
MatchedRegs.ValueVTs.push_back(InOperandVal.getValueType());
MVT RegVT = AsmNodeOperands[CurOp+1].getValueType();
MatchedRegs.RegVTs.push_back(RegVT);
MachineRegisterInfo &RegInfo = DAG.getMachineFunction().getRegInfo();
for (unsigned i = 0, e = InlineAsm::getNumOperandRegisters(OpFlag);
i != e; ++i)
MatchedRegs.Regs.
push_back(RegInfo.createVirtualRegister(TLI.getRegClassFor(RegVT)));
// Use the produced MatchedRegs object to
MatchedRegs.getCopyToRegs(InOperandVal, DAG, getCurDebugLoc(),
Chain, &Flag);
MatchedRegs.AddInlineAsmOperands(1 /*REGUSE*/,
true, OpInfo.getMatchedOperand(),
DAG, AsmNodeOperands);
break;
} else {
assert(((OpFlag & 7) == 4) && "Unknown matching constraint!");
assert((InlineAsm::getNumOperandRegisters(OpFlag)) == 1 &&
"Unexpected number of operands");
// Add information to the INLINEASM node to know about this input.
// See InlineAsm.h isUseOperandTiedToDef.
OpFlag |= 0x80000000 | (OpInfo.getMatchedOperand() << 16);
AsmNodeOperands.push_back(DAG.getTargetConstant(OpFlag,
TLI.getPointerTy()));
AsmNodeOperands.push_back(AsmNodeOperands[CurOp+1]);
break;
}
}
if (OpInfo.ConstraintType == TargetLowering::C_Other) {
assert(!OpInfo.isIndirect &&
"Don't know how to handle indirect other inputs yet!");
std::vector<SDValue> Ops;
TLI.LowerAsmOperandForConstraint(InOperandVal, OpInfo.ConstraintCode[0],
hasMemory, Ops, DAG);
if (Ops.empty()) {
cerr << "llvm: error: Invalid operand for inline asm constraint '"
<< OpInfo.ConstraintCode << "'!\n";
exit(1);
}
// Add information to the INLINEASM node to know about this input.
unsigned ResOpType = 3 /*IMM*/ | (Ops.size() << 3);
AsmNodeOperands.push_back(DAG.getTargetConstant(ResOpType,
TLI.getPointerTy()));
AsmNodeOperands.insert(AsmNodeOperands.end(), Ops.begin(), Ops.end());
break;
} else if (OpInfo.ConstraintType == TargetLowering::C_Memory) {
assert(OpInfo.isIndirect && "Operand must be indirect to be a mem!");
assert(InOperandVal.getValueType() == TLI.getPointerTy() &&
"Memory operands expect pointer values");
// Add information to the INLINEASM node to know about this input.
unsigned ResOpType = 4/*MEM*/ | (1<<3);
AsmNodeOperands.push_back(DAG.getTargetConstant(ResOpType,
TLI.getPointerTy()));
AsmNodeOperands.push_back(InOperandVal);
break;
}
assert((OpInfo.ConstraintType == TargetLowering::C_RegisterClass ||
OpInfo.ConstraintType == TargetLowering::C_Register) &&
"Unknown constraint type!");
assert(!OpInfo.isIndirect &&
"Don't know how to handle indirect register inputs yet!");
// Copy the input into the appropriate registers.
if (OpInfo.AssignedRegs.Regs.empty()) {
cerr << "llvm: error: Couldn't allocate output reg for constraint '"
<< OpInfo.ConstraintCode << "'!\n";
exit(1);
}
OpInfo.AssignedRegs.getCopyToRegs(InOperandVal, DAG, getCurDebugLoc(),
Chain, &Flag);
OpInfo.AssignedRegs.AddInlineAsmOperands(1/*REGUSE*/, false, 0,
DAG, AsmNodeOperands);
break;
}
case InlineAsm::isClobber: {
// Add the clobbered value to the operand list, so that the register
// allocator is aware that the physreg got clobbered.
if (!OpInfo.AssignedRegs.Regs.empty())
OpInfo.AssignedRegs.AddInlineAsmOperands(6 /* EARLYCLOBBER REGDEF */,
false, 0, DAG,AsmNodeOperands);
break;
}
}
}
// Finish up input operands.
AsmNodeOperands[0] = Chain;
if (Flag.getNode()) AsmNodeOperands.push_back(Flag);
Chain = DAG.getNode(ISD::INLINEASM, getCurDebugLoc(),
DAG.getVTList(MVT::Other, MVT::Flag),
&AsmNodeOperands[0], AsmNodeOperands.size());
Flag = Chain.getValue(1);
// If this asm returns a register value, copy the result from that register
// and set it as the value of the call.
if (!RetValRegs.Regs.empty()) {
SDValue Val = RetValRegs.getCopyFromRegs(DAG, getCurDebugLoc(),
Chain, &Flag);
// FIXME: Why don't we do this for inline asms with MRVs?
if (CS.getType()->isSingleValueType() && CS.getType()->isSized()) {
MVT ResultType = TLI.getValueType(CS.getType());
// If any of the results of the inline asm is a vector, it may have the
// wrong width/num elts. This can happen for register classes that can
// contain multiple different value types. The preg or vreg allocated may
// not have the same VT as was expected. Convert it to the right type
// with bit_convert.
if (ResultType != Val.getValueType() && Val.getValueType().isVector()) {
Val = DAG.getNode(ISD::BIT_CONVERT, getCurDebugLoc(),
ResultType, Val);
} else if (ResultType != Val.getValueType() &&
ResultType.isInteger() && Val.getValueType().isInteger()) {
// If a result value was tied to an input value, the computed result may
// have a wider width than the expected result. Extract the relevant
// portion.
Val = DAG.getNode(ISD::TRUNCATE, getCurDebugLoc(), ResultType, Val);
}
assert(ResultType == Val.getValueType() && "Asm result value mismatch!");
}
setValue(CS.getInstruction(), Val);
// Don't need to use this as a chain in this case.
if (!IA->hasSideEffects() && !hasMemory && IndirectStoresToEmit.empty())
return;
}
std::vector<std::pair<SDValue, Value*> > StoresToEmit;
// Process indirect outputs, first output all of the flagged copies out of
// physregs.
for (unsigned i = 0, e = IndirectStoresToEmit.size(); i != e; ++i) {
RegsForValue &OutRegs = IndirectStoresToEmit[i].first;
Value *Ptr = IndirectStoresToEmit[i].second;
SDValue OutVal = OutRegs.getCopyFromRegs(DAG, getCurDebugLoc(),
Chain, &Flag);
StoresToEmit.push_back(std::make_pair(OutVal, Ptr));
}
// Emit the non-flagged stores from the physregs.
SmallVector<SDValue, 8> OutChains;
for (unsigned i = 0, e = StoresToEmit.size(); i != e; ++i)
OutChains.push_back(DAG.getStore(Chain, getCurDebugLoc(),
StoresToEmit[i].first,
getValue(StoresToEmit[i].second),
StoresToEmit[i].second, 0));
if (!OutChains.empty())
Chain = DAG.getNode(ISD::TokenFactor, getCurDebugLoc(), MVT::Other,
&OutChains[0], OutChains.size());
DAG.setRoot(Chain);
}
void SelectionDAGLowering::visitMalloc(MallocInst &I) {
SDValue Src = getValue(I.getOperand(0));
// Scale up by the type size in the original i32 type width. Various
// mid-level optimizers may make assumptions about demanded bits etc from the
// i32-ness of the optimizer: we do not want to promote to i64 and then
// multiply on 64-bit targets.
// FIXME: Malloc inst should go away: PR715.
uint64_t ElementSize = TD->getTypeAllocSize(I.getType()->getElementType());
if (ElementSize != 1)
Src = DAG.getNode(ISD::MUL, getCurDebugLoc(), Src.getValueType(),
Src, DAG.getConstant(ElementSize, Src.getValueType()));
MVT IntPtr = TLI.getPointerTy();
if (IntPtr.bitsLT(Src.getValueType()))
Src = DAG.getNode(ISD::TRUNCATE, getCurDebugLoc(), IntPtr, Src);
else if (IntPtr.bitsGT(Src.getValueType()))
Src = DAG.getNode(ISD::ZERO_EXTEND, getCurDebugLoc(), IntPtr, Src);
TargetLowering::ArgListTy Args;
TargetLowering::ArgListEntry Entry;
Entry.Node = Src;
Entry.Ty = TLI.getTargetData()->getIntPtrType();
Args.push_back(Entry);
std::pair<SDValue,SDValue> Result =
TLI.LowerCallTo(getRoot(), I.getType(), false, false, false, false,
CallingConv::C, PerformTailCallOpt,
DAG.getExternalSymbol("malloc", IntPtr),
Args, DAG, getCurDebugLoc());
setValue(&I, Result.first); // Pointers always fit in registers
DAG.setRoot(Result.second);
}
void SelectionDAGLowering::visitFree(FreeInst &I) {
TargetLowering::ArgListTy Args;
TargetLowering::ArgListEntry Entry;
Entry.Node = getValue(I.getOperand(0));
Entry.Ty = TLI.getTargetData()->getIntPtrType();
Args.push_back(Entry);
MVT IntPtr = TLI.getPointerTy();
std::pair<SDValue,SDValue> Result =
TLI.LowerCallTo(getRoot(), Type::VoidTy, false, false, false, false,
CallingConv::C, PerformTailCallOpt,
DAG.getExternalSymbol("free", IntPtr), Args, DAG,
getCurDebugLoc());
DAG.setRoot(Result.second);
}
void SelectionDAGLowering::visitVAStart(CallInst &I) {
DAG.setRoot(DAG.getNode(ISD::VASTART, getCurDebugLoc(),
MVT::Other, getRoot(),
getValue(I.getOperand(1)),
DAG.getSrcValue(I.getOperand(1))));
}
void SelectionDAGLowering::visitVAArg(VAArgInst &I) {
SDValue V = DAG.getVAArg(TLI.getValueType(I.getType()), getCurDebugLoc(),
getRoot(), getValue(I.getOperand(0)),
DAG.getSrcValue(I.getOperand(0)));
setValue(&I, V);
DAG.setRoot(V.getValue(1));
}
void SelectionDAGLowering::visitVAEnd(CallInst &I) {
DAG.setRoot(DAG.getNode(ISD::VAEND, getCurDebugLoc(),
MVT::Other, getRoot(),
getValue(I.getOperand(1)),
DAG.getSrcValue(I.getOperand(1))));
}
void SelectionDAGLowering::visitVACopy(CallInst &I) {
DAG.setRoot(DAG.getNode(ISD::VACOPY, getCurDebugLoc(),
MVT::Other, getRoot(),
getValue(I.getOperand(1)),
getValue(I.getOperand(2)),
DAG.getSrcValue(I.getOperand(1)),
DAG.getSrcValue(I.getOperand(2))));
}
/// TargetLowering::LowerArguments - This is the default LowerArguments
/// implementation, which just inserts a FORMAL_ARGUMENTS node. FIXME: When all
/// targets are migrated to using FORMAL_ARGUMENTS, this hook should be
/// integrated into SDISel.
void TargetLowering::LowerArguments(Function &F, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &ArgValues,
DebugLoc dl) {
// Add CC# and isVararg as operands to the FORMAL_ARGUMENTS node.
SmallVector<SDValue, 3+16> Ops;
Ops.push_back(DAG.getRoot());
Ops.push_back(DAG.getConstant(F.getCallingConv(), getPointerTy()));
Ops.push_back(DAG.getConstant(F.isVarArg(), getPointerTy()));
// Add one result value for each formal argument.
SmallVector<MVT, 16> RetVals;
unsigned j = 1;
for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end();
I != E; ++I, ++j) {
SmallVector<MVT, 4> ValueVTs;
ComputeValueVTs(*this, I->getType(), ValueVTs);
for (unsigned Value = 0, NumValues = ValueVTs.size();
Value != NumValues; ++Value) {
MVT VT = ValueVTs[Value];
const Type *ArgTy = VT.getTypeForMVT();
ISD::ArgFlagsTy Flags;
unsigned OriginalAlignment =
getTargetData()->getABITypeAlignment(ArgTy);
if (F.paramHasAttr(j, Attribute::ZExt))
Flags.setZExt();
if (F.paramHasAttr(j, Attribute::SExt))
Flags.setSExt();
if (F.paramHasAttr(j, Attribute::InReg))
Flags.setInReg();
if (F.paramHasAttr(j, Attribute::StructRet))
Flags.setSRet();
if (F.paramHasAttr(j, Attribute::ByVal)) {
Flags.setByVal();
const PointerType *Ty = cast<PointerType>(I->getType());
const Type *ElementTy = Ty->getElementType();
unsigned FrameAlign = getByValTypeAlignment(ElementTy);
unsigned FrameSize = getTargetData()->getTypeAllocSize(ElementTy);
// For ByVal, alignment should be passed from FE. BE will guess if
// this info is not there but there are cases it cannot get right.
if (F.getParamAlignment(j))
FrameAlign = F.getParamAlignment(j);
Flags.setByValAlign(FrameAlign);
Flags.setByValSize(FrameSize);
}
if (F.paramHasAttr(j, Attribute::Nest))
Flags.setNest();
Flags.setOrigAlign(OriginalAlignment);
MVT RegisterVT = getRegisterType(VT);
unsigned NumRegs = getNumRegisters(VT);
for (unsigned i = 0; i != NumRegs; ++i) {
RetVals.push_back(RegisterVT);
ISD::ArgFlagsTy MyFlags = Flags;
if (NumRegs > 1 && i == 0)
MyFlags.setSplit();
// if it isn't first piece, alignment must be 1
else if (i > 0)
MyFlags.setOrigAlign(1);
Ops.push_back(DAG.getArgFlags(MyFlags));
}
}
}
RetVals.push_back(MVT::Other);
// Create the node.
SDNode *Result = DAG.getNode(ISD::FORMAL_ARGUMENTS, dl,
DAG.getVTList(&RetVals[0], RetVals.size()),
&Ops[0], Ops.size()).getNode();
// Prelower FORMAL_ARGUMENTS. This isn't required for functionality, but
// allows exposing the loads that may be part of the argument access to the
// first DAGCombiner pass.
SDValue TmpRes = LowerOperation(SDValue(Result, 0), DAG);
// The number of results should match up, except that the lowered one may have
// an extra flag result.
assert((Result->getNumValues() == TmpRes.getNode()->getNumValues() ||
(Result->getNumValues()+1 == TmpRes.getNode()->getNumValues() &&
TmpRes.getValue(Result->getNumValues()).getValueType() == MVT::Flag))
&& "Lowering produced unexpected number of results!");
// The FORMAL_ARGUMENTS node itself is likely no longer needed.
if (Result != TmpRes.getNode() && Result->use_empty()) {
HandleSDNode Dummy(DAG.getRoot());
DAG.RemoveDeadNode(Result);
}
Result = TmpRes.getNode();
unsigned NumArgRegs = Result->getNumValues() - 1;
DAG.setRoot(SDValue(Result, NumArgRegs));
// Set up the return result vector.
unsigned i = 0;
unsigned Idx = 1;
for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E;
++I, ++Idx) {
SmallVector<MVT, 4> ValueVTs;
ComputeValueVTs(*this, I->getType(), ValueVTs);
for (unsigned Value = 0, NumValues = ValueVTs.size();
Value != NumValues; ++Value) {
MVT VT = ValueVTs[Value];
MVT PartVT = getRegisterType(VT);
unsigned NumParts = getNumRegisters(VT);
SmallVector<SDValue, 4> Parts(NumParts);
for (unsigned j = 0; j != NumParts; ++j)
Parts[j] = SDValue(Result, i++);
ISD::NodeType AssertOp = ISD::DELETED_NODE;
if (F.paramHasAttr(Idx, Attribute::SExt))
AssertOp = ISD::AssertSext;
else if (F.paramHasAttr(Idx, Attribute::ZExt))
AssertOp = ISD::AssertZext;
ArgValues.push_back(getCopyFromParts(DAG, dl, &Parts[0], NumParts,
PartVT, VT, AssertOp));
}
}
assert(i == NumArgRegs && "Argument register count mismatch!");
}
/// TargetLowering::LowerCallTo - This is the default LowerCallTo
/// implementation, which just inserts an ISD::CALL node, which is later custom
/// lowered by the target to something concrete. FIXME: When all targets are
/// migrated to using ISD::CALL, this hook should be integrated into SDISel.
std::pair<SDValue, SDValue>
TargetLowering::LowerCallTo(SDValue Chain, const Type *RetTy,
bool RetSExt, bool RetZExt, bool isVarArg,
bool isInreg,
unsigned CallingConv, bool isTailCall,
SDValue Callee,
ArgListTy &Args, SelectionDAG &DAG, DebugLoc dl) {
assert((!isTailCall || PerformTailCallOpt) &&
"isTailCall set when tail-call optimizations are disabled!");
SmallVector<SDValue, 32> Ops;
Ops.push_back(Chain); // Op#0 - Chain
Ops.push_back(Callee);
// Handle all of the outgoing arguments.
for (unsigned i = 0, e = Args.size(); i != e; ++i) {
SmallVector<MVT, 4> ValueVTs;
ComputeValueVTs(*this, Args[i].Ty, ValueVTs);
for (unsigned Value = 0, NumValues = ValueVTs.size();
Value != NumValues; ++Value) {
MVT VT = ValueVTs[Value];
const Type *ArgTy = VT.getTypeForMVT();
SDValue Op = SDValue(Args[i].Node.getNode(),
Args[i].Node.getResNo() + Value);
ISD::ArgFlagsTy Flags;
unsigned OriginalAlignment =
getTargetData()->getABITypeAlignment(ArgTy);
if (Args[i].isZExt)
Flags.setZExt();
if (Args[i].isSExt)
Flags.setSExt();
if (Args[i].isInReg)
Flags.setInReg();
if (Args[i].isSRet)
Flags.setSRet();
if (Args[i].isByVal) {
Flags.setByVal();
const PointerType *Ty = cast<PointerType>(Args[i].Ty);
const Type *ElementTy = Ty->getElementType();
unsigned FrameAlign = getByValTypeAlignment(ElementTy);
unsigned FrameSize = getTargetData()->getTypeAllocSize(ElementTy);
// For ByVal, alignment should come from FE. BE will guess if this
// info is not there but there are cases it cannot get right.
if (Args[i].Alignment)
FrameAlign = Args[i].Alignment;
Flags.setByValAlign(FrameAlign);
Flags.setByValSize(FrameSize);
}
if (Args[i].isNest)
Flags.setNest();
Flags.setOrigAlign(OriginalAlignment);
MVT PartVT = getRegisterType(VT);
unsigned NumParts = getNumRegisters(VT);
SmallVector<SDValue, 4> Parts(NumParts);
ISD::NodeType ExtendKind = ISD::ANY_EXTEND;
if (Args[i].isSExt)
ExtendKind = ISD::SIGN_EXTEND;
else if (Args[i].isZExt)
ExtendKind = ISD::ZERO_EXTEND;
getCopyToParts(DAG, dl, Op, &Parts[0], NumParts, PartVT, ExtendKind);
for (unsigned i = 0; i != NumParts; ++i) {
// if it isn't first piece, alignment must be 1
ISD::ArgFlagsTy MyFlags = Flags;
if (NumParts > 1 && i == 0)
MyFlags.setSplit();
else if (i != 0)
MyFlags.setOrigAlign(1);
Ops.push_back(Parts[i]);
Ops.push_back(DAG.getArgFlags(MyFlags));
}
}
}
// Figure out the result value types. We start by making a list of
// the potentially illegal return value types.
SmallVector<MVT, 4> LoweredRetTys;
SmallVector<MVT, 4> RetTys;
ComputeValueVTs(*this, RetTy, RetTys);
// Then we translate that to a list of legal types.
for (unsigned I = 0, E = RetTys.size(); I != E; ++I) {
MVT VT = RetTys[I];
MVT RegisterVT = getRegisterType(VT);
unsigned NumRegs = getNumRegisters(VT);
for (unsigned i = 0; i != NumRegs; ++i)
LoweredRetTys.push_back(RegisterVT);
}
LoweredRetTys.push_back(MVT::Other); // Always has a chain.
// Create the CALL node.
SDValue Res = DAG.getCall(CallingConv, dl,
isVarArg, isTailCall, isInreg,
DAG.getVTList(&LoweredRetTys[0],
LoweredRetTys.size()),
&Ops[0], Ops.size()
);
Chain = Res.getValue(LoweredRetTys.size() - 1);
// Gather up the call result into a single value.
if (RetTy != Type::VoidTy && !RetTys.empty()) {
ISD::NodeType AssertOp = ISD::DELETED_NODE;
if (RetSExt)
AssertOp = ISD::AssertSext;
else if (RetZExt)
AssertOp = ISD::AssertZext;
SmallVector<SDValue, 4> ReturnValues;
unsigned RegNo = 0;
for (unsigned I = 0, E = RetTys.size(); I != E; ++I) {
MVT VT = RetTys[I];
MVT RegisterVT = getRegisterType(VT);
unsigned NumRegs = getNumRegisters(VT);
unsigned RegNoEnd = NumRegs + RegNo;
SmallVector<SDValue, 4> Results;
for (; RegNo != RegNoEnd; ++RegNo)
Results.push_back(Res.getValue(RegNo));
SDValue ReturnValue =
getCopyFromParts(DAG, dl, &Results[0], NumRegs, RegisterVT, VT,
AssertOp);
ReturnValues.push_back(ReturnValue);
}
Res = DAG.getNode(ISD::MERGE_VALUES, dl,
DAG.getVTList(&RetTys[0], RetTys.size()),
&ReturnValues[0], ReturnValues.size());
}
return std::make_pair(Res, Chain);
}
void TargetLowering::LowerOperationWrapper(SDNode *N,
SmallVectorImpl<SDValue> &Results,
SelectionDAG &DAG) {
SDValue Res = LowerOperation(SDValue(N, 0), DAG);
if (Res.getNode())
Results.push_back(Res);
}
SDValue TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) {
assert(0 && "LowerOperation not implemented for this target!");
abort();
return SDValue();
}
void SelectionDAGLowering::CopyValueToVirtualRegister(Value *V, unsigned Reg) {
SDValue Op = getValue(V);
assert((Op.getOpcode() != ISD::CopyFromReg ||
cast<RegisterSDNode>(Op.getOperand(1))->getReg() != Reg) &&
"Copy from a reg to the same reg!");
assert(!TargetRegisterInfo::isPhysicalRegister(Reg) && "Is a physreg");
RegsForValue RFV(TLI, Reg, V->getType());
SDValue Chain = DAG.getEntryNode();
RFV.getCopyToRegs(Op, DAG, getCurDebugLoc(), Chain, 0);
PendingExports.push_back(Chain);
}
#include "llvm/CodeGen/SelectionDAGISel.h"
void SelectionDAGISel::
LowerArguments(BasicBlock *LLVMBB) {
// If this is the entry block, emit arguments.
Function &F = *LLVMBB->getParent();
SDValue OldRoot = SDL->DAG.getRoot();
SmallVector<SDValue, 16> Args;
TLI.LowerArguments(F, SDL->DAG, Args, SDL->getCurDebugLoc());
unsigned a = 0;
for (Function::arg_iterator AI = F.arg_begin(), E = F.arg_end();
AI != E; ++AI) {
SmallVector<MVT, 4> ValueVTs;
ComputeValueVTs(TLI, AI->getType(), ValueVTs);
unsigned NumValues = ValueVTs.size();
if (!AI->use_empty()) {
SDL->setValue(AI, SDL->DAG.getMergeValues(&Args[a], NumValues,
SDL->getCurDebugLoc()));
// If this argument is live outside of the entry block, insert a copy from
// whereever we got it to the vreg that other BB's will reference it as.
SDL->CopyToExportRegsIfNeeded(AI);
}
a += NumValues;
}
// Finally, if the target has anything special to do, allow it to do so.
// FIXME: this should insert code into the DAG!
EmitFunctionEntryCode(F, SDL->DAG.getMachineFunction());
}
/// Handle PHI nodes in successor blocks. Emit code into the SelectionDAG to
/// ensure constants are generated when needed. Remember the virtual registers
/// that need to be added to the Machine PHI nodes as input. We cannot just
/// directly add them, because expansion might result in multiple MBB's for one
/// BB. As such, the start of the BB might correspond to a different MBB than
/// the end.
///
void
SelectionDAGISel::HandlePHINodesInSuccessorBlocks(BasicBlock *LLVMBB) {
TerminatorInst *TI = LLVMBB->getTerminator();
SmallPtrSet<MachineBasicBlock *, 4> SuccsHandled;
// Check successor nodes' PHI nodes that expect a constant to be available
// from this block.
for (unsigned succ = 0, e = TI->getNumSuccessors(); succ != e; ++succ) {
BasicBlock *SuccBB = TI->getSuccessor(succ);
if (!isa<PHINode>(SuccBB->begin())) continue;
MachineBasicBlock *SuccMBB = FuncInfo->MBBMap[SuccBB];
// If this terminator has multiple identical successors (common for
// switches), only handle each succ once.
if (!SuccsHandled.insert(SuccMBB)) continue;
MachineBasicBlock::iterator MBBI = SuccMBB->begin();
PHINode *PN;
// At this point we know that there is a 1-1 correspondence between LLVM PHI
// nodes and Machine PHI nodes, but the incoming operands have not been
// emitted yet.
for (BasicBlock::iterator I = SuccBB->begin();
(PN = dyn_cast<PHINode>(I)); ++I) {
// Ignore dead phi's.
if (PN->use_empty()) continue;
unsigned Reg;
Value *PHIOp = PN->getIncomingValueForBlock(LLVMBB);
if (Constant *C = dyn_cast<Constant>(PHIOp)) {
unsigned &RegOut = SDL->ConstantsOut[C];
if (RegOut == 0) {
RegOut = FuncInfo->CreateRegForValue(C);
SDL->CopyValueToVirtualRegister(C, RegOut);
}
Reg = RegOut;
} else {
Reg = FuncInfo->ValueMap[PHIOp];
if (Reg == 0) {
assert(isa<AllocaInst>(PHIOp) &&
FuncInfo->StaticAllocaMap.count(cast<AllocaInst>(PHIOp)) &&
"Didn't codegen value into a register!??");
Reg = FuncInfo->CreateRegForValue(PHIOp);
SDL->CopyValueToVirtualRegister(PHIOp, Reg);
}
}
// Remember that this register needs to added to the machine PHI node as
// the input for this MBB.
SmallVector<MVT, 4> ValueVTs;
ComputeValueVTs(TLI, PN->getType(), ValueVTs);
for (unsigned vti = 0, vte = ValueVTs.size(); vti != vte; ++vti) {
MVT VT = ValueVTs[vti];
unsigned NumRegisters = TLI.getNumRegisters(VT);
for (unsigned i = 0, e = NumRegisters; i != e; ++i)
SDL->PHINodesToUpdate.push_back(std::make_pair(MBBI++, Reg+i));
Reg += NumRegisters;
}
}
}
SDL->ConstantsOut.clear();
}
/// This is the Fast-ISel version of HandlePHINodesInSuccessorBlocks. It only
/// supports legal types, and it emits MachineInstrs directly instead of
/// creating SelectionDAG nodes.
///
bool
SelectionDAGISel::HandlePHINodesInSuccessorBlocksFast(BasicBlock *LLVMBB,
FastISel *F) {
TerminatorInst *TI = LLVMBB->getTerminator();
SmallPtrSet<MachineBasicBlock *, 4> SuccsHandled;
unsigned OrigNumPHINodesToUpdate = SDL->PHINodesToUpdate.size();
// Check successor nodes' PHI nodes that expect a constant to be available
// from this block.
for (unsigned succ = 0, e = TI->getNumSuccessors(); succ != e; ++succ) {
BasicBlock *SuccBB = TI->getSuccessor(succ);
if (!isa<PHINode>(SuccBB->begin())) continue;
MachineBasicBlock *SuccMBB = FuncInfo->MBBMap[SuccBB];
// If this terminator has multiple identical successors (common for
// switches), only handle each succ once.
if (!SuccsHandled.insert(SuccMBB)) continue;
MachineBasicBlock::iterator MBBI = SuccMBB->begin();
PHINode *PN;
// At this point we know that there is a 1-1 correspondence between LLVM PHI
// nodes and Machine PHI nodes, but the incoming operands have not been
// emitted yet.
for (BasicBlock::iterator I = SuccBB->begin();
(PN = dyn_cast<PHINode>(I)); ++I) {
// Ignore dead phi's.
if (PN->use_empty()) continue;
// Only handle legal types. Two interesting things to note here. First,
// by bailing out early, we may leave behind some dead instructions,
// since SelectionDAG's HandlePHINodesInSuccessorBlocks will insert its
// own moves. Second, this check is necessary becuase FastISel doesn't
// use CreateRegForValue to create registers, so it always creates
// exactly one register for each non-void instruction.
MVT VT = TLI.getValueType(PN->getType(), /*AllowUnknown=*/true);
if (VT == MVT::Other || !TLI.isTypeLegal(VT)) {
// Promote MVT::i1.
if (VT == MVT::i1)
VT = TLI.getTypeToTransformTo(VT);
else {
SDL->PHINodesToUpdate.resize(OrigNumPHINodesToUpdate);
return false;
}
}
Value *PHIOp = PN->getIncomingValueForBlock(LLVMBB);
unsigned Reg = F->getRegForValue(PHIOp);
if (Reg == 0) {
SDL->PHINodesToUpdate.resize(OrigNumPHINodesToUpdate);
return false;
}
SDL->PHINodesToUpdate.push_back(std::make_pair(MBBI++, Reg));
}
}
return true;
}