llvm-6502/lib/Target/CellSPU/SPUISelDAGToDAG.cpp
2008-09-04 15:39:15 +00:00

705 lines
22 KiB
C++

//===-- SPUISelDAGToDAG.cpp - CellSPU pattern matching inst selector ------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines a pattern matching instruction selector for the Cell SPU,
// converting from a legalized dag to a SPU-target dag.
//
//===----------------------------------------------------------------------===//
#include "SPU.h"
#include "SPUTargetMachine.h"
#include "SPUISelLowering.h"
#include "SPUHazardRecognizers.h"
#include "SPUFrameInfo.h"
#include "SPURegisterNames.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/SelectionDAGISel.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Constants.h"
#include "llvm/GlobalValue.h"
#include "llvm/Intrinsics.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/Compiler.h"
#include <queue>
#include <set>
using namespace llvm;
namespace {
//! ConstantSDNode predicate for i32 sign-extended, 10-bit immediates
bool
isI64IntS10Immediate(ConstantSDNode *CN)
{
return isS10Constant(CN->getSignExtended());
}
//! ConstantSDNode predicate for i32 sign-extended, 10-bit immediates
bool
isI32IntS10Immediate(ConstantSDNode *CN)
{
return isS10Constant(CN->getSignExtended());
}
#if 0
//! SDNode predicate for sign-extended, 10-bit immediate values
bool
isI32IntS10Immediate(SDNode *N)
{
return (N->getOpcode() == ISD::Constant
&& isI32IntS10Immediate(cast<ConstantSDNode>(N)));
}
#endif
//! ConstantSDNode predicate for i32 unsigned 10-bit immediate values
bool
isI32IntU10Immediate(ConstantSDNode *CN)
{
return isU10Constant(CN->getSignExtended());
}
//! ConstantSDNode predicate for i16 sign-extended, 10-bit immediate values
bool
isI16IntS10Immediate(ConstantSDNode *CN)
{
return isS10Constant(CN->getSignExtended());
}
//! SDNode predicate for i16 sign-extended, 10-bit immediate values
bool
isI16IntS10Immediate(SDNode *N)
{
return (N->getOpcode() == ISD::Constant
&& isI16IntS10Immediate(cast<ConstantSDNode>(N)));
}
//! ConstantSDNode predicate for i16 unsigned 10-bit immediate values
bool
isI16IntU10Immediate(ConstantSDNode *CN)
{
return isU10Constant((short) CN->getValue());
}
//! SDNode predicate for i16 sign-extended, 10-bit immediate values
bool
isI16IntU10Immediate(SDNode *N)
{
return (N->getOpcode() == ISD::Constant
&& isI16IntU10Immediate(cast<ConstantSDNode>(N)));
}
//! ConstantSDNode predicate for signed 16-bit values
/*!
\arg CN The constant SelectionDAG node holding the value
\arg Imm The returned 16-bit value, if returning true
This predicate tests the value in \a CN to see whether it can be
represented as a 16-bit, sign-extended quantity. Returns true if
this is the case.
*/
bool
isIntS16Immediate(ConstantSDNode *CN, short &Imm)
{
MVT vt = CN->getValueType(0);
Imm = (short) CN->getValue();
if (vt.getSimpleVT() >= MVT::i1 && vt.getSimpleVT() <= MVT::i16) {
return true;
} else if (vt == MVT::i32) {
int32_t i_val = (int32_t) CN->getValue();
short s_val = (short) i_val;
return i_val == s_val;
} else {
int64_t i_val = (int64_t) CN->getValue();
short s_val = (short) i_val;
return i_val == s_val;
}
return false;
}
//! SDNode predicate for signed 16-bit values.
bool
isIntS16Immediate(SDNode *N, short &Imm)
{
return (N->getOpcode() == ISD::Constant
&& isIntS16Immediate(cast<ConstantSDNode>(N), Imm));
}
//! ConstantFPSDNode predicate for representing floats as 16-bit sign ext.
static bool
isFPS16Immediate(ConstantFPSDNode *FPN, short &Imm)
{
MVT vt = FPN->getValueType(0);
if (vt == MVT::f32) {
int val = FloatToBits(FPN->getValueAPF().convertToFloat());
int sval = (int) ((val << 16) >> 16);
Imm = (short) val;
return val == sval;
}
return false;
}
bool
isHighLow(const SDValue &Op)
{
return (Op.getOpcode() == SPUISD::IndirectAddr
&& ((Op.getOperand(0).getOpcode() == SPUISD::Hi
&& Op.getOperand(1).getOpcode() == SPUISD::Lo)
|| (Op.getOperand(0).getOpcode() == SPUISD::Lo
&& Op.getOperand(1).getOpcode() == SPUISD::Hi)));
}
//===------------------------------------------------------------------===//
//! MVT to "useful stuff" mapping structure:
struct valtype_map_s {
MVT VT;
unsigned ldresult_ins; /// LDRESULT instruction (0 = undefined)
bool ldresult_imm; /// LDRESULT instruction requires immediate?
int prefslot_byte; /// Byte offset of the "preferred" slot
};
const valtype_map_s valtype_map[] = {
{ MVT::i1, 0, false, 3 },
{ MVT::i8, SPU::ORBIr8, true, 3 },
{ MVT::i16, SPU::ORHIr16, true, 2 },
{ MVT::i32, SPU::ORIr32, true, 0 },
{ MVT::i64, SPU::ORr64, false, 0 },
{ MVT::f32, SPU::ORf32, false, 0 },
{ MVT::f64, SPU::ORf64, false, 0 },
// vector types... (sigh!)
{ MVT::v16i8, 0, false, 0 },
{ MVT::v8i16, 0, false, 0 },
{ MVT::v4i32, 0, false, 0 },
{ MVT::v2i64, 0, false, 0 },
{ MVT::v4f32, 0, false, 0 },
{ MVT::v2f64, 0, false, 0 }
};
const size_t n_valtype_map = sizeof(valtype_map) / sizeof(valtype_map[0]);
const valtype_map_s *getValueTypeMapEntry(MVT VT)
{
const valtype_map_s *retval = 0;
for (size_t i = 0; i < n_valtype_map; ++i) {
if (valtype_map[i].VT == VT) {
retval = valtype_map + i;
break;
}
}
#ifndef NDEBUG
if (retval == 0) {
cerr << "SPUISelDAGToDAG.cpp: getValueTypeMapEntry returns NULL for "
<< VT.getMVTString()
<< "\n";
abort();
}
#endif
return retval;
}
}
namespace {
//===--------------------------------------------------------------------===//
/// SPUDAGToDAGISel - Cell SPU-specific code to select SPU machine
/// instructions for SelectionDAG operations.
///
class SPUDAGToDAGISel :
public SelectionDAGISel
{
SPUTargetMachine &TM;
SPUTargetLowering &SPUtli;
unsigned GlobalBaseReg;
public:
explicit SPUDAGToDAGISel(SPUTargetMachine &tm) :
SelectionDAGISel(*tm.getTargetLowering()),
TM(tm),
SPUtli(*tm.getTargetLowering())
{}
virtual bool runOnFunction(Function &Fn) {
// Make sure we re-emit a set of the global base reg if necessary
GlobalBaseReg = 0;
SelectionDAGISel::runOnFunction(Fn);
return true;
}
/// getI32Imm - Return a target constant with the specified value, of type
/// i32.
inline SDValue getI32Imm(uint32_t Imm) {
return CurDAG->getTargetConstant(Imm, MVT::i32);
}
/// getI64Imm - Return a target constant with the specified value, of type
/// i64.
inline SDValue getI64Imm(uint64_t Imm) {
return CurDAG->getTargetConstant(Imm, MVT::i64);
}
/// getSmallIPtrImm - Return a target constant of pointer type.
inline SDValue getSmallIPtrImm(unsigned Imm) {
return CurDAG->getTargetConstant(Imm, SPUtli.getPointerTy());
}
/// Select - Convert the specified operand from a target-independent to a
/// target-specific node if it hasn't already been changed.
SDNode *Select(SDValue Op);
//! Returns true if the address N is an A-form (local store) address
bool SelectAFormAddr(SDValue Op, SDValue N, SDValue &Base,
SDValue &Index);
//! D-form address predicate
bool SelectDFormAddr(SDValue Op, SDValue N, SDValue &Base,
SDValue &Index);
/// Alternate D-form address using i7 offset predicate
bool SelectDForm2Addr(SDValue Op, SDValue N, SDValue &Disp,
SDValue &Base);
/// D-form address selection workhorse
bool DFormAddressPredicate(SDValue Op, SDValue N, SDValue &Disp,
SDValue &Base, int minOffset, int maxOffset);
//! Address predicate if N can be expressed as an indexed [r+r] operation.
bool SelectXFormAddr(SDValue Op, SDValue N, SDValue &Base,
SDValue &Index);
/// SelectInlineAsmMemoryOperand - Implement addressing mode selection for
/// inline asm expressions.
virtual bool SelectInlineAsmMemoryOperand(const SDValue &Op,
char ConstraintCode,
std::vector<SDValue> &OutOps) {
SDValue Op0, Op1;
switch (ConstraintCode) {
default: return true;
case 'm': // memory
if (!SelectDFormAddr(Op, Op, Op0, Op1)
&& !SelectAFormAddr(Op, Op, Op0, Op1))
SelectXFormAddr(Op, Op, Op0, Op1);
break;
case 'o': // offsetable
if (!SelectDFormAddr(Op, Op, Op0, Op1)
&& !SelectAFormAddr(Op, Op, Op0, Op1)) {
Op0 = Op;
AddToISelQueue(Op0); // r+0.
Op1 = getSmallIPtrImm(0);
}
break;
case 'v': // not offsetable
#if 1
assert(0 && "InlineAsmMemoryOperand 'v' constraint not handled.");
#else
SelectAddrIdxOnly(Op, Op, Op0, Op1);
#endif
break;
}
OutOps.push_back(Op0);
OutOps.push_back(Op1);
return false;
}
/// InstructionSelect - This callback is invoked by
/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
virtual void InstructionSelect();
virtual const char *getPassName() const {
return "Cell SPU DAG->DAG Pattern Instruction Selection";
}
/// CreateTargetHazardRecognizer - Return the hazard recognizer to use for
/// this target when scheduling the DAG.
virtual HazardRecognizer *CreateTargetHazardRecognizer() {
const TargetInstrInfo *II = TM.getInstrInfo();
assert(II && "No InstrInfo?");
return new SPUHazardRecognizer(*II);
}
// Include the pieces autogenerated from the target description.
#include "SPUGenDAGISel.inc"
};
}
/// InstructionSelect - This callback is invoked by
/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
void
SPUDAGToDAGISel::InstructionSelect()
{
DEBUG(BB->dump());
// Select target instructions for the DAG.
SelectRoot();
CurDAG->RemoveDeadNodes();
}
/*!
\arg Op The ISD instructio operand
\arg N The address to be tested
\arg Base The base address
\arg Index The base address index
*/
bool
SPUDAGToDAGISel::SelectAFormAddr(SDValue Op, SDValue N, SDValue &Base,
SDValue &Index) {
// These match the addr256k operand type:
MVT OffsVT = MVT::i16;
SDValue Zero = CurDAG->getTargetConstant(0, OffsVT);
switch (N.getOpcode()) {
case ISD::Constant:
case ISD::ConstantPool:
case ISD::GlobalAddress:
cerr << "SPU SelectAFormAddr: Constant/Pool/Global not lowered.\n";
abort();
/*NOTREACHED*/
case ISD::TargetConstant:
case ISD::TargetGlobalAddress:
case ISD::TargetJumpTable:
cerr << "SPUSelectAFormAddr: Target Constant/Pool/Global not wrapped as "
<< "A-form address.\n";
abort();
/*NOTREACHED*/
case SPUISD::AFormAddr:
// Just load from memory if there's only a single use of the location,
// otherwise, this will get handled below with D-form offset addresses
if (N.hasOneUse()) {
SDValue Op0 = N.getOperand(0);
switch (Op0.getOpcode()) {
case ISD::TargetConstantPool:
case ISD::TargetJumpTable:
Base = Op0;
Index = Zero;
return true;
case ISD::TargetGlobalAddress: {
GlobalAddressSDNode *GSDN = cast<GlobalAddressSDNode>(Op0);
GlobalValue *GV = GSDN->getGlobal();
if (GV->getAlignment() == 16) {
Base = Op0;
Index = Zero;
return true;
}
break;
}
}
}
break;
}
return false;
}
bool
SPUDAGToDAGISel::SelectDForm2Addr(SDValue Op, SDValue N, SDValue &Disp,
SDValue &Base) {
const int minDForm2Offset = -(1 << 7);
const int maxDForm2Offset = (1 << 7) - 1;
return DFormAddressPredicate(Op, N, Disp, Base, minDForm2Offset,
maxDForm2Offset);
}
/*!
\arg Op The ISD instruction (ignored)
\arg N The address to be tested
\arg Base Base address register/pointer
\arg Index Base address index
Examine the input address by a base register plus a signed 10-bit
displacement, [r+I10] (D-form address).
\return true if \a N is a D-form address with \a Base and \a Index set
to non-empty SDValue instances.
*/
bool
SPUDAGToDAGISel::SelectDFormAddr(SDValue Op, SDValue N, SDValue &Base,
SDValue &Index) {
return DFormAddressPredicate(Op, N, Base, Index,
SPUFrameInfo::minFrameOffset(),
SPUFrameInfo::maxFrameOffset());
}
bool
SPUDAGToDAGISel::DFormAddressPredicate(SDValue Op, SDValue N, SDValue &Base,
SDValue &Index, int minOffset,
int maxOffset) {
unsigned Opc = N.getOpcode();
MVT PtrTy = SPUtli.getPointerTy();
if (Opc == ISD::FrameIndex) {
// Stack frame index must be less than 512 (divided by 16):
FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>(N);
int FI = int(FIN->getIndex());
DEBUG(cerr << "SelectDFormAddr: ISD::FrameIndex = "
<< FI << "\n");
if (SPUFrameInfo::FItoStackOffset(FI) < maxOffset) {
Base = CurDAG->getTargetConstant(0, PtrTy);
Index = CurDAG->getTargetFrameIndex(FI, PtrTy);
return true;
}
} else if (Opc == ISD::ADD) {
// Generated by getelementptr
const SDValue Op0 = N.getOperand(0);
const SDValue Op1 = N.getOperand(1);
if ((Op0.getOpcode() == SPUISD::Hi && Op1.getOpcode() == SPUISD::Lo)
|| (Op1.getOpcode() == SPUISD::Hi && Op0.getOpcode() == SPUISD::Lo)) {
Base = CurDAG->getTargetConstant(0, PtrTy);
Index = N;
return true;
} else if (Op1.getOpcode() == ISD::Constant
|| Op1.getOpcode() == ISD::TargetConstant) {
ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Op1);
int32_t offset = int32_t(CN->getSignExtended());
if (Op0.getOpcode() == ISD::FrameIndex) {
FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>(Op0);
int FI = int(FIN->getIndex());
DEBUG(cerr << "SelectDFormAddr: ISD::ADD offset = " << offset
<< " frame index = " << FI << "\n");
if (SPUFrameInfo::FItoStackOffset(FI) < maxOffset) {
Base = CurDAG->getTargetConstant(offset, PtrTy);
Index = CurDAG->getTargetFrameIndex(FI, PtrTy);
return true;
}
} else if (offset > minOffset && offset < maxOffset) {
Base = CurDAG->getTargetConstant(offset, PtrTy);
Index = Op0;
return true;
}
} else if (Op0.getOpcode() == ISD::Constant
|| Op0.getOpcode() == ISD::TargetConstant) {
ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Op0);
int32_t offset = int32_t(CN->getSignExtended());
if (Op1.getOpcode() == ISD::FrameIndex) {
FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>(Op1);
int FI = int(FIN->getIndex());
DEBUG(cerr << "SelectDFormAddr: ISD::ADD offset = " << offset
<< " frame index = " << FI << "\n");
if (SPUFrameInfo::FItoStackOffset(FI) < maxOffset) {
Base = CurDAG->getTargetConstant(offset, PtrTy);
Index = CurDAG->getTargetFrameIndex(FI, PtrTy);
return true;
}
} else if (offset > minOffset && offset < maxOffset) {
Base = CurDAG->getTargetConstant(offset, PtrTy);
Index = Op1;
return true;
}
}
} else if (Opc == SPUISD::IndirectAddr) {
// Indirect with constant offset -> D-Form address
const SDValue Op0 = N.getOperand(0);
const SDValue Op1 = N.getOperand(1);
if (Op0.getOpcode() == SPUISD::Hi
&& Op1.getOpcode() == SPUISD::Lo) {
// (SPUindirect (SPUhi <arg>, 0), (SPUlo <arg>, 0))
Base = CurDAG->getTargetConstant(0, PtrTy);
Index = N;
return true;
} else if (isa<ConstantSDNode>(Op0) || isa<ConstantSDNode>(Op1)) {
int32_t offset = 0;
SDValue idxOp;
if (isa<ConstantSDNode>(Op1)) {
ConstantSDNode *CN = cast<ConstantSDNode>(Op1);
offset = int32_t(CN->getSignExtended());
idxOp = Op0;
} else if (isa<ConstantSDNode>(Op0)) {
ConstantSDNode *CN = cast<ConstantSDNode>(Op0);
offset = int32_t(CN->getSignExtended());
idxOp = Op1;
}
if (offset >= minOffset && offset <= maxOffset) {
Base = CurDAG->getTargetConstant(offset, PtrTy);
Index = idxOp;
return true;
}
}
} else if (Opc == SPUISD::AFormAddr) {
Base = CurDAG->getTargetConstant(0, N.getValueType());
Index = N;
return true;
} else if (Opc == SPUISD::LDRESULT) {
Base = CurDAG->getTargetConstant(0, N.getValueType());
Index = N;
return true;
}
return false;
}
/*!
\arg Op The ISD instruction operand
\arg N The address operand
\arg Base The base pointer operand
\arg Index The offset/index operand
If the address \a N can be expressed as a [r + s10imm] address, returns false.
Otherwise, creates two operands, Base and Index that will become the [r+r]
address.
*/
bool
SPUDAGToDAGISel::SelectXFormAddr(SDValue Op, SDValue N, SDValue &Base,
SDValue &Index) {
if (SelectAFormAddr(Op, N, Base, Index)
|| SelectDFormAddr(Op, N, Base, Index))
return false;
// All else fails, punt and use an X-form address:
Base = N.getOperand(0);
Index = N.getOperand(1);
return true;
}
//! Convert the operand from a target-independent to a target-specific node
/*!
*/
SDNode *
SPUDAGToDAGISel::Select(SDValue Op) {
SDNode *N = Op.getNode();
unsigned Opc = N->getOpcode();
int n_ops = -1;
unsigned NewOpc;
MVT OpVT = Op.getValueType();
SDValue Ops[8];
if (N->isMachineOpcode()) {
return NULL; // Already selected.
} else if (Opc == ISD::FrameIndex) {
// Selects to (add $sp, FI * stackSlotSize)
int FI =
SPUFrameInfo::FItoStackOffset(cast<FrameIndexSDNode>(N)->getIndex());
MVT PtrVT = SPUtli.getPointerTy();
// Adjust stack slot to actual offset in frame:
if (isS10Constant(FI)) {
DEBUG(cerr << "SPUDAGToDAGISel: Replacing FrameIndex with AIr32 $sp, "
<< FI
<< "\n");
NewOpc = SPU::AIr32;
Ops[0] = CurDAG->getRegister(SPU::R1, PtrVT);
Ops[1] = CurDAG->getTargetConstant(FI, PtrVT);
n_ops = 2;
} else {
DEBUG(cerr << "SPUDAGToDAGISel: Replacing FrameIndex with Ar32 $sp, "
<< FI
<< "\n");
NewOpc = SPU::Ar32;
Ops[0] = CurDAG->getRegister(SPU::R1, PtrVT);
Ops[1] = CurDAG->getConstant(FI, PtrVT);
n_ops = 2;
AddToISelQueue(Ops[1]);
}
} else if (Opc == ISD::ZERO_EXTEND) {
// (zero_extend:i16 (and:i8 <arg>, <const>))
const SDValue &Op1 = N->getOperand(0);
if (Op.getValueType() == MVT::i16 && Op1.getValueType() == MVT::i8) {
if (Op1.getOpcode() == ISD::AND) {
// Fold this into a single ANDHI. This is often seen in expansions of i1
// to i8, then i8 to i16 in logical/branching operations.
DEBUG(cerr << "CellSPU: Coalescing (zero_extend:i16 (and:i8 "
"<arg>, <const>))\n");
NewOpc = SPU::ANDHIi8i16;
Ops[0] = Op1.getOperand(0);
Ops[1] = Op1.getOperand(1);
n_ops = 2;
}
}
} else if (Opc == SPUISD::LDRESULT) {
// Custom select instructions for LDRESULT
MVT VT = N->getValueType(0);
SDValue Arg = N->getOperand(0);
SDValue Chain = N->getOperand(1);
SDNode *Result;
const valtype_map_s *vtm = getValueTypeMapEntry(VT);
if (vtm->ldresult_ins == 0) {
cerr << "LDRESULT for unsupported type: "
<< VT.getMVTString()
<< "\n";
abort();
}
AddToISelQueue(Arg);
Opc = vtm->ldresult_ins;
if (vtm->ldresult_imm) {
SDValue Zero = CurDAG->getTargetConstant(0, VT);
AddToISelQueue(Zero);
Result = CurDAG->getTargetNode(Opc, VT, MVT::Other, Arg, Zero, Chain);
} else {
Result = CurDAG->getTargetNode(Opc, MVT::Other, Arg, Arg, Chain);
}
Chain = SDValue(Result, 1);
AddToISelQueue(Chain);
return Result;
} else if (Opc == SPUISD::IndirectAddr) {
SDValue Op0 = Op.getOperand(0);
if (Op0.getOpcode() == SPUISD::LDRESULT) {
/* || Op0.getOpcode() == SPUISD::AFormAddr) */
// (IndirectAddr (LDRESULT, imm))
SDValue Op1 = Op.getOperand(1);
MVT VT = Op.getValueType();
DEBUG(cerr << "CellSPU: IndirectAddr(LDRESULT, imm):\nOp0 = ");
DEBUG(Op.getOperand(0).getNode()->dump(CurDAG));
DEBUG(cerr << "\nOp1 = ");
DEBUG(Op.getOperand(1).getNode()->dump(CurDAG));
DEBUG(cerr << "\n");
if (Op1.getOpcode() == ISD::Constant) {
ConstantSDNode *CN = cast<ConstantSDNode>(Op1);
Op1 = CurDAG->getTargetConstant(CN->getValue(), VT);
NewOpc = (isI32IntS10Immediate(CN) ? SPU::AIr32 : SPU::Ar32);
AddToISelQueue(Op0);
AddToISelQueue(Op1);
Ops[0] = Op0;
Ops[1] = Op1;
n_ops = 2;
}
}
}
if (n_ops > 0) {
if (N->hasOneUse())
return CurDAG->SelectNodeTo(N, NewOpc, OpVT, Ops, n_ops);
else
return CurDAG->getTargetNode(NewOpc, OpVT, Ops, n_ops);
} else
return SelectCode(Op);
}
/// createPPCISelDag - This pass converts a legalized DAG into a
/// SPU-specific DAG, ready for instruction scheduling.
///
FunctionPass *llvm::createSPUISelDag(SPUTargetMachine &TM) {
return new SPUDAGToDAGISel(TM);
}