llvm-6502/lib/Target/XCore/XCoreISelLowering.cpp
Duncan Sands 1440e8b918 Inside the calling convention logic LocVT is always a simple
value type, so there is no point in passing it around using
an EVT.  Use the simpler MVT everywhere.  Rather than trying
to propagate this information maximally in all the code that
using the calling convention stuff, I chose to do a mainly
low impact change instead.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118167 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-03 11:35:31 +00:00

1559 lines
59 KiB
C++

//===-- XCoreISelLowering.cpp - XCore DAG Lowering Implementation ------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the XCoreTargetLowering class.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "xcore-lower"
#include "XCoreISelLowering.h"
#include "XCoreMachineFunctionInfo.h"
#include "XCore.h"
#include "XCoreTargetObjectFile.h"
#include "XCoreTargetMachine.h"
#include "XCoreSubtarget.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/Intrinsics.h"
#include "llvm/CallingConv.h"
#include "llvm/GlobalVariable.h"
#include "llvm/GlobalAlias.h"
#include "llvm/CodeGen/CallingConvLower.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/SelectionDAGISel.h"
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/ADT/VectorExtras.h"
#include <queue>
#include <set>
using namespace llvm;
const char *XCoreTargetLowering::
getTargetNodeName(unsigned Opcode) const
{
switch (Opcode)
{
case XCoreISD::BL : return "XCoreISD::BL";
case XCoreISD::PCRelativeWrapper : return "XCoreISD::PCRelativeWrapper";
case XCoreISD::DPRelativeWrapper : return "XCoreISD::DPRelativeWrapper";
case XCoreISD::CPRelativeWrapper : return "XCoreISD::CPRelativeWrapper";
case XCoreISD::STWSP : return "XCoreISD::STWSP";
case XCoreISD::RETSP : return "XCoreISD::RETSP";
case XCoreISD::LADD : return "XCoreISD::LADD";
case XCoreISD::LSUB : return "XCoreISD::LSUB";
case XCoreISD::LMUL : return "XCoreISD::LMUL";
case XCoreISD::MACCU : return "XCoreISD::MACCU";
case XCoreISD::MACCS : return "XCoreISD::MACCS";
case XCoreISD::BR_JT : return "XCoreISD::BR_JT";
case XCoreISD::BR_JT32 : return "XCoreISD::BR_JT32";
default : return NULL;
}
}
XCoreTargetLowering::XCoreTargetLowering(XCoreTargetMachine &XTM)
: TargetLowering(XTM, new XCoreTargetObjectFile()),
TM(XTM),
Subtarget(*XTM.getSubtargetImpl()) {
// Set up the register classes.
addRegisterClass(MVT::i32, XCore::GRRegsRegisterClass);
// Compute derived properties from the register classes
computeRegisterProperties();
// Division is expensive
setIntDivIsCheap(false);
setShiftAmountType(MVT::i32);
setStackPointerRegisterToSaveRestore(XCore::SP);
setSchedulingPreference(Sched::RegPressure);
// Use i32 for setcc operations results (slt, sgt, ...).
setBooleanContents(ZeroOrOneBooleanContent);
// XCore does not have the NodeTypes below.
setOperationAction(ISD::BR_CC, MVT::Other, Expand);
setOperationAction(ISD::SELECT_CC, MVT::i32, Custom);
setOperationAction(ISD::ADDC, MVT::i32, Expand);
setOperationAction(ISD::ADDE, MVT::i32, Expand);
setOperationAction(ISD::SUBC, MVT::i32, Expand);
setOperationAction(ISD::SUBE, MVT::i32, Expand);
// Stop the combiner recombining select and set_cc
setOperationAction(ISD::SELECT_CC, MVT::Other, Expand);
// 64bit
setOperationAction(ISD::ADD, MVT::i64, Custom);
setOperationAction(ISD::SUB, MVT::i64, Custom);
setOperationAction(ISD::SMUL_LOHI, MVT::i32, Custom);
setOperationAction(ISD::UMUL_LOHI, MVT::i32, Custom);
setOperationAction(ISD::MULHS, MVT::i32, Expand);
setOperationAction(ISD::MULHU, MVT::i32, Expand);
setOperationAction(ISD::SHL_PARTS, MVT::i32, Expand);
setOperationAction(ISD::SRA_PARTS, MVT::i32, Expand);
setOperationAction(ISD::SRL_PARTS, MVT::i32, Expand);
// Bit Manipulation
setOperationAction(ISD::CTPOP, MVT::i32, Expand);
setOperationAction(ISD::ROTL , MVT::i32, Expand);
setOperationAction(ISD::ROTR , MVT::i32, Expand);
setOperationAction(ISD::TRAP, MVT::Other, Legal);
// Jump tables.
setOperationAction(ISD::BR_JT, MVT::Other, Custom);
setOperationAction(ISD::GlobalAddress, MVT::i32, Custom);
setOperationAction(ISD::BlockAddress, MVT::i32 , Custom);
// Thread Local Storage
setOperationAction(ISD::GlobalTLSAddress, MVT::i32, Custom);
// Conversion of i64 -> double produces constantpool nodes
setOperationAction(ISD::ConstantPool, MVT::i32, Custom);
// Loads
setLoadExtAction(ISD::EXTLOAD, MVT::i1, Promote);
setLoadExtAction(ISD::ZEXTLOAD, MVT::i1, Promote);
setLoadExtAction(ISD::SEXTLOAD, MVT::i1, Promote);
setLoadExtAction(ISD::SEXTLOAD, MVT::i8, Expand);
setLoadExtAction(ISD::ZEXTLOAD, MVT::i16, Expand);
// Custom expand misaligned loads / stores.
setOperationAction(ISD::LOAD, MVT::i32, Custom);
setOperationAction(ISD::STORE, MVT::i32, Custom);
// Varargs
setOperationAction(ISD::VAEND, MVT::Other, Expand);
setOperationAction(ISD::VACOPY, MVT::Other, Expand);
setOperationAction(ISD::VAARG, MVT::Other, Custom);
setOperationAction(ISD::VASTART, MVT::Other, Custom);
// Dynamic stack
setOperationAction(ISD::STACKSAVE, MVT::Other, Expand);
setOperationAction(ISD::STACKRESTORE, MVT::Other, Expand);
setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Expand);
maxStoresPerMemset = 4;
maxStoresPerMemmove = maxStoresPerMemcpy = 2;
// We have target-specific dag combine patterns for the following nodes:
setTargetDAGCombine(ISD::STORE);
setTargetDAGCombine(ISD::ADD);
}
SDValue XCoreTargetLowering::
LowerOperation(SDValue Op, SelectionDAG &DAG) const {
switch (Op.getOpcode())
{
case ISD::GlobalAddress: return LowerGlobalAddress(Op, DAG);
case ISD::GlobalTLSAddress: return LowerGlobalTLSAddress(Op, DAG);
case ISD::BlockAddress: return LowerBlockAddress(Op, DAG);
case ISD::ConstantPool: return LowerConstantPool(Op, DAG);
case ISD::BR_JT: return LowerBR_JT(Op, DAG);
case ISD::LOAD: return LowerLOAD(Op, DAG);
case ISD::STORE: return LowerSTORE(Op, DAG);
case ISD::SELECT_CC: return LowerSELECT_CC(Op, DAG);
case ISD::VAARG: return LowerVAARG(Op, DAG);
case ISD::VASTART: return LowerVASTART(Op, DAG);
case ISD::SMUL_LOHI: return LowerSMUL_LOHI(Op, DAG);
case ISD::UMUL_LOHI: return LowerUMUL_LOHI(Op, DAG);
// FIXME: Remove these when LegalizeDAGTypes lands.
case ISD::ADD:
case ISD::SUB: return ExpandADDSUB(Op.getNode(), DAG);
case ISD::FRAMEADDR: return LowerFRAMEADDR(Op, DAG);
default:
llvm_unreachable("unimplemented operand");
return SDValue();
}
}
/// ReplaceNodeResults - Replace the results of node with an illegal result
/// type with new values built out of custom code.
void XCoreTargetLowering::ReplaceNodeResults(SDNode *N,
SmallVectorImpl<SDValue>&Results,
SelectionDAG &DAG) const {
switch (N->getOpcode()) {
default:
llvm_unreachable("Don't know how to custom expand this!");
return;
case ISD::ADD:
case ISD::SUB:
Results.push_back(ExpandADDSUB(N, DAG));
return;
}
}
/// getFunctionAlignment - Return the Log2 alignment of this function.
unsigned XCoreTargetLowering::
getFunctionAlignment(const Function *) const {
return 1;
}
//===----------------------------------------------------------------------===//
// Misc Lower Operation implementation
//===----------------------------------------------------------------------===//
SDValue XCoreTargetLowering::
LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const
{
DebugLoc dl = Op.getDebugLoc();
SDValue Cond = DAG.getNode(ISD::SETCC, dl, MVT::i32, Op.getOperand(2),
Op.getOperand(3), Op.getOperand(4));
return DAG.getNode(ISD::SELECT, dl, MVT::i32, Cond, Op.getOperand(0),
Op.getOperand(1));
}
SDValue XCoreTargetLowering::
getGlobalAddressWrapper(SDValue GA, const GlobalValue *GV,
SelectionDAG &DAG) const
{
// FIXME there is no actual debug info here
DebugLoc dl = GA.getDebugLoc();
if (isa<Function>(GV)) {
return DAG.getNode(XCoreISD::PCRelativeWrapper, dl, MVT::i32, GA);
}
const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
if (!GVar) {
// If GV is an alias then use the aliasee to determine constness
if (const GlobalAlias *GA = dyn_cast<GlobalAlias>(GV))
GVar = dyn_cast_or_null<GlobalVariable>(GA->resolveAliasedGlobal());
}
bool isConst = GVar && GVar->isConstant();
if (isConst) {
return DAG.getNode(XCoreISD::CPRelativeWrapper, dl, MVT::i32, GA);
}
return DAG.getNode(XCoreISD::DPRelativeWrapper, dl, MVT::i32, GA);
}
SDValue XCoreTargetLowering::
LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const
{
const GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
SDValue GA = DAG.getTargetGlobalAddress(GV, Op.getDebugLoc(), MVT::i32);
// If it's a debug information descriptor, don't mess with it.
if (DAG.isVerifiedDebugInfoDesc(Op))
return GA;
return getGlobalAddressWrapper(GA, GV, DAG);
}
static inline SDValue BuildGetId(SelectionDAG &DAG, DebugLoc dl) {
return DAG.getNode(ISD::INTRINSIC_WO_CHAIN, dl, MVT::i32,
DAG.getConstant(Intrinsic::xcore_getid, MVT::i32));
}
static inline bool isZeroLengthArray(const Type *Ty) {
const ArrayType *AT = dyn_cast_or_null<ArrayType>(Ty);
return AT && (AT->getNumElements() == 0);
}
SDValue XCoreTargetLowering::
LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const
{
// FIXME there isn't really debug info here
DebugLoc dl = Op.getDebugLoc();
// transform to label + getid() * size
const GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
SDValue GA = DAG.getTargetGlobalAddress(GV, dl, MVT::i32);
const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
if (!GVar) {
// If GV is an alias then use the aliasee to determine size
if (const GlobalAlias *GA = dyn_cast<GlobalAlias>(GV))
GVar = dyn_cast_or_null<GlobalVariable>(GA->resolveAliasedGlobal());
}
if (! GVar) {
llvm_unreachable("Thread local object not a GlobalVariable?");
return SDValue();
}
const Type *Ty = cast<PointerType>(GV->getType())->getElementType();
if (!Ty->isSized() || isZeroLengthArray(Ty)) {
#ifndef NDEBUG
errs() << "Size of thread local object " << GVar->getName()
<< " is unknown\n";
#endif
llvm_unreachable(0);
}
SDValue base = getGlobalAddressWrapper(GA, GV, DAG);
const TargetData *TD = TM.getTargetData();
unsigned Size = TD->getTypeAllocSize(Ty);
SDValue offset = DAG.getNode(ISD::MUL, dl, MVT::i32, BuildGetId(DAG, dl),
DAG.getConstant(Size, MVT::i32));
return DAG.getNode(ISD::ADD, dl, MVT::i32, base, offset);
}
SDValue XCoreTargetLowering::
LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const
{
DebugLoc DL = Op.getDebugLoc();
const BlockAddress *BA = cast<BlockAddressSDNode>(Op)->getBlockAddress();
SDValue Result = DAG.getBlockAddress(BA, getPointerTy(), /*isTarget=*/true);
return DAG.getNode(XCoreISD::PCRelativeWrapper, DL, getPointerTy(), Result);
}
SDValue XCoreTargetLowering::
LowerConstantPool(SDValue Op, SelectionDAG &DAG) const
{
ConstantPoolSDNode *CP = cast<ConstantPoolSDNode>(Op);
// FIXME there isn't really debug info here
DebugLoc dl = CP->getDebugLoc();
EVT PtrVT = Op.getValueType();
SDValue Res;
if (CP->isMachineConstantPoolEntry()) {
Res = DAG.getTargetConstantPool(CP->getMachineCPVal(), PtrVT,
CP->getAlignment());
} else {
Res = DAG.getTargetConstantPool(CP->getConstVal(), PtrVT,
CP->getAlignment());
}
return DAG.getNode(XCoreISD::CPRelativeWrapper, dl, MVT::i32, Res);
}
unsigned XCoreTargetLowering::getJumpTableEncoding() const {
return MachineJumpTableInfo::EK_Inline;
}
SDValue XCoreTargetLowering::
LowerBR_JT(SDValue Op, SelectionDAG &DAG) const
{
SDValue Chain = Op.getOperand(0);
SDValue Table = Op.getOperand(1);
SDValue Index = Op.getOperand(2);
DebugLoc dl = Op.getDebugLoc();
JumpTableSDNode *JT = cast<JumpTableSDNode>(Table);
unsigned JTI = JT->getIndex();
MachineFunction &MF = DAG.getMachineFunction();
const MachineJumpTableInfo *MJTI = MF.getJumpTableInfo();
SDValue TargetJT = DAG.getTargetJumpTable(JT->getIndex(), MVT::i32);
unsigned NumEntries = MJTI->getJumpTables()[JTI].MBBs.size();
if (NumEntries <= 32) {
return DAG.getNode(XCoreISD::BR_JT, dl, MVT::Other, Chain, TargetJT, Index);
}
assert((NumEntries >> 31) == 0);
SDValue ScaledIndex = DAG.getNode(ISD::SHL, dl, MVT::i32, Index,
DAG.getConstant(1, MVT::i32));
return DAG.getNode(XCoreISD::BR_JT32, dl, MVT::Other, Chain, TargetJT,
ScaledIndex);
}
static bool
IsWordAlignedBasePlusConstantOffset(SDValue Addr, SDValue &AlignedBase,
int64_t &Offset)
{
if (Addr.getOpcode() != ISD::ADD) {
return false;
}
ConstantSDNode *CN = 0;
if (!(CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1)))) {
return false;
}
int64_t off = CN->getSExtValue();
const SDValue &Base = Addr.getOperand(0);
const SDValue *Root = &Base;
if (Base.getOpcode() == ISD::ADD &&
Base.getOperand(1).getOpcode() == ISD::SHL) {
ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Base.getOperand(1)
.getOperand(1));
if (CN && (CN->getSExtValue() >= 2)) {
Root = &Base.getOperand(0);
}
}
if (isa<FrameIndexSDNode>(*Root)) {
// All frame indicies are word aligned
AlignedBase = Base;
Offset = off;
return true;
}
if (Root->getOpcode() == XCoreISD::DPRelativeWrapper ||
Root->getOpcode() == XCoreISD::CPRelativeWrapper) {
// All dp / cp relative addresses are word aligned
AlignedBase = Base;
Offset = off;
return true;
}
return false;
}
SDValue XCoreTargetLowering::
LowerLOAD(SDValue Op, SelectionDAG &DAG) const {
LoadSDNode *LD = cast<LoadSDNode>(Op);
assert(LD->getExtensionType() == ISD::NON_EXTLOAD &&
"Unexpected extension type");
assert(LD->getMemoryVT() == MVT::i32 && "Unexpected load EVT");
if (allowsUnalignedMemoryAccesses(LD->getMemoryVT()))
return SDValue();
unsigned ABIAlignment = getTargetData()->
getABITypeAlignment(LD->getMemoryVT().getTypeForEVT(*DAG.getContext()));
// Leave aligned load alone.
if (LD->getAlignment() >= ABIAlignment)
return SDValue();
SDValue Chain = LD->getChain();
SDValue BasePtr = LD->getBasePtr();
DebugLoc DL = Op.getDebugLoc();
SDValue Base;
int64_t Offset;
if (!LD->isVolatile() &&
IsWordAlignedBasePlusConstantOffset(BasePtr, Base, Offset)) {
if (Offset % 4 == 0) {
// We've managed to infer better alignment information than the load
// already has. Use an aligned load.
//
return DAG.getLoad(getPointerTy(), DL, Chain, BasePtr,
MachinePointerInfo(),
false, false, 0);
}
// Lower to
// ldw low, base[offset >> 2]
// ldw high, base[(offset >> 2) + 1]
// shr low_shifted, low, (offset & 0x3) * 8
// shl high_shifted, high, 32 - (offset & 0x3) * 8
// or result, low_shifted, high_shifted
SDValue LowOffset = DAG.getConstant(Offset & ~0x3, MVT::i32);
SDValue HighOffset = DAG.getConstant((Offset & ~0x3) + 4, MVT::i32);
SDValue LowShift = DAG.getConstant((Offset & 0x3) * 8, MVT::i32);
SDValue HighShift = DAG.getConstant(32 - (Offset & 0x3) * 8, MVT::i32);
SDValue LowAddr = DAG.getNode(ISD::ADD, DL, MVT::i32, Base, LowOffset);
SDValue HighAddr = DAG.getNode(ISD::ADD, DL, MVT::i32, Base, HighOffset);
SDValue Low = DAG.getLoad(getPointerTy(), DL, Chain,
LowAddr, MachinePointerInfo(), false, false, 0);
SDValue High = DAG.getLoad(getPointerTy(), DL, Chain,
HighAddr, MachinePointerInfo(), false, false, 0);
SDValue LowShifted = DAG.getNode(ISD::SRL, DL, MVT::i32, Low, LowShift);
SDValue HighShifted = DAG.getNode(ISD::SHL, DL, MVT::i32, High, HighShift);
SDValue Result = DAG.getNode(ISD::OR, DL, MVT::i32, LowShifted, HighShifted);
Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Low.getValue(1),
High.getValue(1));
SDValue Ops[] = { Result, Chain };
return DAG.getMergeValues(Ops, 2, DL);
}
if (LD->getAlignment() == 2) {
SDValue Low = DAG.getExtLoad(ISD::ZEXTLOAD, MVT::i32, DL, Chain,
BasePtr, LD->getPointerInfo(), MVT::i16,
LD->isVolatile(), LD->isNonTemporal(), 2);
SDValue HighAddr = DAG.getNode(ISD::ADD, DL, MVT::i32, BasePtr,
DAG.getConstant(2, MVT::i32));
SDValue High = DAG.getExtLoad(ISD::EXTLOAD, MVT::i32, DL, Chain,
HighAddr,
LD->getPointerInfo().getWithOffset(2),
MVT::i16, LD->isVolatile(),
LD->isNonTemporal(), 2);
SDValue HighShifted = DAG.getNode(ISD::SHL, DL, MVT::i32, High,
DAG.getConstant(16, MVT::i32));
SDValue Result = DAG.getNode(ISD::OR, DL, MVT::i32, Low, HighShifted);
Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Low.getValue(1),
High.getValue(1));
SDValue Ops[] = { Result, Chain };
return DAG.getMergeValues(Ops, 2, DL);
}
// Lower to a call to __misaligned_load(BasePtr).
const Type *IntPtrTy = getTargetData()->getIntPtrType(*DAG.getContext());
TargetLowering::ArgListTy Args;
TargetLowering::ArgListEntry Entry;
Entry.Ty = IntPtrTy;
Entry.Node = BasePtr;
Args.push_back(Entry);
std::pair<SDValue, SDValue> CallResult =
LowerCallTo(Chain, IntPtrTy, false, false,
false, false, 0, CallingConv::C, false,
/*isReturnValueUsed=*/true,
DAG.getExternalSymbol("__misaligned_load", getPointerTy()),
Args, DAG, DL);
SDValue Ops[] =
{ CallResult.first, CallResult.second };
return DAG.getMergeValues(Ops, 2, DL);
}
SDValue XCoreTargetLowering::
LowerSTORE(SDValue Op, SelectionDAG &DAG) const
{
StoreSDNode *ST = cast<StoreSDNode>(Op);
assert(!ST->isTruncatingStore() && "Unexpected store type");
assert(ST->getMemoryVT() == MVT::i32 && "Unexpected store EVT");
if (allowsUnalignedMemoryAccesses(ST->getMemoryVT())) {
return SDValue();
}
unsigned ABIAlignment = getTargetData()->
getABITypeAlignment(ST->getMemoryVT().getTypeForEVT(*DAG.getContext()));
// Leave aligned store alone.
if (ST->getAlignment() >= ABIAlignment) {
return SDValue();
}
SDValue Chain = ST->getChain();
SDValue BasePtr = ST->getBasePtr();
SDValue Value = ST->getValue();
DebugLoc dl = Op.getDebugLoc();
if (ST->getAlignment() == 2) {
SDValue Low = Value;
SDValue High = DAG.getNode(ISD::SRL, dl, MVT::i32, Value,
DAG.getConstant(16, MVT::i32));
SDValue StoreLow = DAG.getTruncStore(Chain, dl, Low, BasePtr,
ST->getPointerInfo(), MVT::i16,
ST->isVolatile(), ST->isNonTemporal(),
2);
SDValue HighAddr = DAG.getNode(ISD::ADD, dl, MVT::i32, BasePtr,
DAG.getConstant(2, MVT::i32));
SDValue StoreHigh = DAG.getTruncStore(Chain, dl, High, HighAddr,
ST->getPointerInfo().getWithOffset(2),
MVT::i16, ST->isVolatile(),
ST->isNonTemporal(), 2);
return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, StoreLow, StoreHigh);
}
// Lower to a call to __misaligned_store(BasePtr, Value).
const Type *IntPtrTy = getTargetData()->getIntPtrType(*DAG.getContext());
TargetLowering::ArgListTy Args;
TargetLowering::ArgListEntry Entry;
Entry.Ty = IntPtrTy;
Entry.Node = BasePtr;
Args.push_back(Entry);
Entry.Node = Value;
Args.push_back(Entry);
std::pair<SDValue, SDValue> CallResult =
LowerCallTo(Chain, Type::getVoidTy(*DAG.getContext()), false, false,
false, false, 0, CallingConv::C, false,
/*isReturnValueUsed=*/true,
DAG.getExternalSymbol("__misaligned_store", getPointerTy()),
Args, DAG, dl);
return CallResult.second;
}
SDValue XCoreTargetLowering::
LowerSMUL_LOHI(SDValue Op, SelectionDAG &DAG) const
{
assert(Op.getValueType() == MVT::i32 && Op.getOpcode() == ISD::SMUL_LOHI &&
"Unexpected operand to lower!");
DebugLoc dl = Op.getDebugLoc();
SDValue LHS = Op.getOperand(0);
SDValue RHS = Op.getOperand(1);
SDValue Zero = DAG.getConstant(0, MVT::i32);
SDValue Hi = DAG.getNode(XCoreISD::MACCS, dl,
DAG.getVTList(MVT::i32, MVT::i32), Zero, Zero,
LHS, RHS);
SDValue Lo(Hi.getNode(), 1);
SDValue Ops[] = { Lo, Hi };
return DAG.getMergeValues(Ops, 2, dl);
}
SDValue XCoreTargetLowering::
LowerUMUL_LOHI(SDValue Op, SelectionDAG &DAG) const
{
assert(Op.getValueType() == MVT::i32 && Op.getOpcode() == ISD::UMUL_LOHI &&
"Unexpected operand to lower!");
DebugLoc dl = Op.getDebugLoc();
SDValue LHS = Op.getOperand(0);
SDValue RHS = Op.getOperand(1);
SDValue Zero = DAG.getConstant(0, MVT::i32);
SDValue Hi = DAG.getNode(XCoreISD::LMUL, dl,
DAG.getVTList(MVT::i32, MVT::i32), LHS, RHS,
Zero, Zero);
SDValue Lo(Hi.getNode(), 1);
SDValue Ops[] = { Lo, Hi };
return DAG.getMergeValues(Ops, 2, dl);
}
/// isADDADDMUL - Return whether Op is in a form that is equivalent to
/// add(add(mul(x,y),a),b). If requireIntermediatesHaveOneUse is true then
/// each intermediate result in the calculation must also have a single use.
/// If the Op is in the correct form the constituent parts are written to Mul0,
/// Mul1, Addend0 and Addend1.
static bool
isADDADDMUL(SDValue Op, SDValue &Mul0, SDValue &Mul1, SDValue &Addend0,
SDValue &Addend1, bool requireIntermediatesHaveOneUse)
{
if (Op.getOpcode() != ISD::ADD)
return false;
SDValue N0 = Op.getOperand(0);
SDValue N1 = Op.getOperand(1);
SDValue AddOp;
SDValue OtherOp;
if (N0.getOpcode() == ISD::ADD) {
AddOp = N0;
OtherOp = N1;
} else if (N1.getOpcode() == ISD::ADD) {
AddOp = N1;
OtherOp = N0;
} else {
return false;
}
if (requireIntermediatesHaveOneUse && !AddOp.hasOneUse())
return false;
if (OtherOp.getOpcode() == ISD::MUL) {
// add(add(a,b),mul(x,y))
if (requireIntermediatesHaveOneUse && !OtherOp.hasOneUse())
return false;
Mul0 = OtherOp.getOperand(0);
Mul1 = OtherOp.getOperand(1);
Addend0 = AddOp.getOperand(0);
Addend1 = AddOp.getOperand(1);
return true;
}
if (AddOp.getOperand(0).getOpcode() == ISD::MUL) {
// add(add(mul(x,y),a),b)
if (requireIntermediatesHaveOneUse && !AddOp.getOperand(0).hasOneUse())
return false;
Mul0 = AddOp.getOperand(0).getOperand(0);
Mul1 = AddOp.getOperand(0).getOperand(1);
Addend0 = AddOp.getOperand(1);
Addend1 = OtherOp;
return true;
}
if (AddOp.getOperand(1).getOpcode() == ISD::MUL) {
// add(add(a,mul(x,y)),b)
if (requireIntermediatesHaveOneUse && !AddOp.getOperand(1).hasOneUse())
return false;
Mul0 = AddOp.getOperand(1).getOperand(0);
Mul1 = AddOp.getOperand(1).getOperand(1);
Addend0 = AddOp.getOperand(0);
Addend1 = OtherOp;
return true;
}
return false;
}
SDValue XCoreTargetLowering::
TryExpandADDWithMul(SDNode *N, SelectionDAG &DAG) const
{
SDValue Mul;
SDValue Other;
if (N->getOperand(0).getOpcode() == ISD::MUL) {
Mul = N->getOperand(0);
Other = N->getOperand(1);
} else if (N->getOperand(1).getOpcode() == ISD::MUL) {
Mul = N->getOperand(1);
Other = N->getOperand(0);
} else {
return SDValue();
}
DebugLoc dl = N->getDebugLoc();
SDValue LL, RL, AddendL, AddendH;
LL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Mul.getOperand(0), DAG.getConstant(0, MVT::i32));
RL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Mul.getOperand(1), DAG.getConstant(0, MVT::i32));
AddendL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Other, DAG.getConstant(0, MVT::i32));
AddendH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Other, DAG.getConstant(1, MVT::i32));
APInt HighMask = APInt::getHighBitsSet(64, 32);
unsigned LHSSB = DAG.ComputeNumSignBits(Mul.getOperand(0));
unsigned RHSSB = DAG.ComputeNumSignBits(Mul.getOperand(1));
if (DAG.MaskedValueIsZero(Mul.getOperand(0), HighMask) &&
DAG.MaskedValueIsZero(Mul.getOperand(1), HighMask)) {
// The inputs are both zero-extended.
SDValue Hi = DAG.getNode(XCoreISD::MACCU, dl,
DAG.getVTList(MVT::i32, MVT::i32), AddendH,
AddendL, LL, RL);
SDValue Lo(Hi.getNode(), 1);
return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
}
if (LHSSB > 32 && RHSSB > 32) {
// The inputs are both sign-extended.
SDValue Hi = DAG.getNode(XCoreISD::MACCS, dl,
DAG.getVTList(MVT::i32, MVT::i32), AddendH,
AddendL, LL, RL);
SDValue Lo(Hi.getNode(), 1);
return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
}
SDValue LH, RH;
LH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Mul.getOperand(0), DAG.getConstant(1, MVT::i32));
RH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Mul.getOperand(1), DAG.getConstant(1, MVT::i32));
SDValue Hi = DAG.getNode(XCoreISD::MACCU, dl,
DAG.getVTList(MVT::i32, MVT::i32), AddendH,
AddendL, LL, RL);
SDValue Lo(Hi.getNode(), 1);
RH = DAG.getNode(ISD::MUL, dl, MVT::i32, LL, RH);
LH = DAG.getNode(ISD::MUL, dl, MVT::i32, LH, RL);
Hi = DAG.getNode(ISD::ADD, dl, MVT::i32, Hi, RH);
Hi = DAG.getNode(ISD::ADD, dl, MVT::i32, Hi, LH);
return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
}
SDValue XCoreTargetLowering::
ExpandADDSUB(SDNode *N, SelectionDAG &DAG) const
{
assert(N->getValueType(0) == MVT::i64 &&
(N->getOpcode() == ISD::ADD || N->getOpcode() == ISD::SUB) &&
"Unknown operand to lower!");
if (N->getOpcode() == ISD::ADD) {
SDValue Result = TryExpandADDWithMul(N, DAG);
if (Result.getNode() != 0)
return Result;
}
DebugLoc dl = N->getDebugLoc();
// Extract components
SDValue LHSL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
N->getOperand(0), DAG.getConstant(0, MVT::i32));
SDValue LHSH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
N->getOperand(0), DAG.getConstant(1, MVT::i32));
SDValue RHSL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
N->getOperand(1), DAG.getConstant(0, MVT::i32));
SDValue RHSH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
N->getOperand(1), DAG.getConstant(1, MVT::i32));
// Expand
unsigned Opcode = (N->getOpcode() == ISD::ADD) ? XCoreISD::LADD :
XCoreISD::LSUB;
SDValue Zero = DAG.getConstant(0, MVT::i32);
SDValue Carry = DAG.getNode(Opcode, dl, DAG.getVTList(MVT::i32, MVT::i32),
LHSL, RHSL, Zero);
SDValue Lo(Carry.getNode(), 1);
SDValue Ignored = DAG.getNode(Opcode, dl, DAG.getVTList(MVT::i32, MVT::i32),
LHSH, RHSH, Carry);
SDValue Hi(Ignored.getNode(), 1);
// Merge the pieces
return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
}
SDValue XCoreTargetLowering::
LowerVAARG(SDValue Op, SelectionDAG &DAG) const
{
llvm_unreachable("unimplemented");
// FIX Arguments passed by reference need a extra dereference.
SDNode *Node = Op.getNode();
DebugLoc dl = Node->getDebugLoc();
const Value *V = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
EVT VT = Node->getValueType(0);
SDValue VAList = DAG.getLoad(getPointerTy(), dl, Node->getOperand(0),
Node->getOperand(1), MachinePointerInfo(V),
false, false, 0);
// Increment the pointer, VAList, to the next vararg
SDValue Tmp3 = DAG.getNode(ISD::ADD, dl, getPointerTy(), VAList,
DAG.getConstant(VT.getSizeInBits(),
getPointerTy()));
// Store the incremented VAList to the legalized pointer
Tmp3 = DAG.getStore(VAList.getValue(1), dl, Tmp3, Node->getOperand(1),
MachinePointerInfo(V), false, false, 0);
// Load the actual argument out of the pointer VAList
return DAG.getLoad(VT, dl, Tmp3, VAList, MachinePointerInfo(),
false, false, 0);
}
SDValue XCoreTargetLowering::
LowerVASTART(SDValue Op, SelectionDAG &DAG) const
{
DebugLoc dl = Op.getDebugLoc();
// vastart stores the address of the VarArgsFrameIndex slot into the
// memory location argument
MachineFunction &MF = DAG.getMachineFunction();
XCoreFunctionInfo *XFI = MF.getInfo<XCoreFunctionInfo>();
SDValue Addr = DAG.getFrameIndex(XFI->getVarArgsFrameIndex(), MVT::i32);
return DAG.getStore(Op.getOperand(0), dl, Addr, Op.getOperand(1),
MachinePointerInfo(), false, false, 0);
}
SDValue XCoreTargetLowering::LowerFRAMEADDR(SDValue Op,
SelectionDAG &DAG) const {
DebugLoc dl = Op.getDebugLoc();
// Depths > 0 not supported yet!
if (cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() > 0)
return SDValue();
MachineFunction &MF = DAG.getMachineFunction();
const TargetRegisterInfo *RegInfo = getTargetMachine().getRegisterInfo();
return DAG.getCopyFromReg(DAG.getEntryNode(), dl,
RegInfo->getFrameRegister(MF), MVT::i32);
}
//===----------------------------------------------------------------------===//
// Calling Convention Implementation
//===----------------------------------------------------------------------===//
#include "XCoreGenCallingConv.inc"
//===----------------------------------------------------------------------===//
// Call Calling Convention Implementation
//===----------------------------------------------------------------------===//
/// XCore call implementation
SDValue
XCoreTargetLowering::LowerCall(SDValue Chain, SDValue Callee,
CallingConv::ID CallConv, bool isVarArg,
bool &isTailCall,
const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<SDValue> &OutVals,
const SmallVectorImpl<ISD::InputArg> &Ins,
DebugLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals) const {
// XCore target does not yet support tail call optimization.
isTailCall = false;
// For now, only CallingConv::C implemented
switch (CallConv)
{
default:
llvm_unreachable("Unsupported calling convention");
case CallingConv::Fast:
case CallingConv::C:
return LowerCCCCallTo(Chain, Callee, CallConv, isVarArg, isTailCall,
Outs, OutVals, Ins, dl, DAG, InVals);
}
}
/// LowerCCCCallTo - functions arguments are copied from virtual
/// regs to (physical regs)/(stack frame), CALLSEQ_START and
/// CALLSEQ_END are emitted.
/// TODO: isTailCall, sret.
SDValue
XCoreTargetLowering::LowerCCCCallTo(SDValue Chain, SDValue Callee,
CallingConv::ID CallConv, bool isVarArg,
bool isTailCall,
const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<SDValue> &OutVals,
const SmallVectorImpl<ISD::InputArg> &Ins,
DebugLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals) const {
// Analyze operands of the call, assigning locations to each operand.
SmallVector<CCValAssign, 16> ArgLocs;
CCState CCInfo(CallConv, isVarArg, getTargetMachine(),
ArgLocs, *DAG.getContext());
// The ABI dictates there should be one stack slot available to the callee
// on function entry (for saving lr).
CCInfo.AllocateStack(4, 4);
CCInfo.AnalyzeCallOperands(Outs, CC_XCore);
// Get a count of how many bytes are to be pushed on the stack.
unsigned NumBytes = CCInfo.getNextStackOffset();
Chain = DAG.getCALLSEQ_START(Chain,DAG.getConstant(NumBytes,
getPointerTy(), true));
SmallVector<std::pair<unsigned, SDValue>, 4> RegsToPass;
SmallVector<SDValue, 12> MemOpChains;
// Walk the register/memloc assignments, inserting copies/loads.
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
CCValAssign &VA = ArgLocs[i];
SDValue Arg = OutVals[i];
// Promote the value if needed.
switch (VA.getLocInfo()) {
default: llvm_unreachable("Unknown loc info!");
case CCValAssign::Full: break;
case CCValAssign::SExt:
Arg = DAG.getNode(ISD::SIGN_EXTEND, dl, VA.getLocVT(), Arg);
break;
case CCValAssign::ZExt:
Arg = DAG.getNode(ISD::ZERO_EXTEND, dl, VA.getLocVT(), Arg);
break;
case CCValAssign::AExt:
Arg = DAG.getNode(ISD::ANY_EXTEND, dl, VA.getLocVT(), Arg);
break;
}
// Arguments that can be passed on register must be kept at
// RegsToPass vector
if (VA.isRegLoc()) {
RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
} else {
assert(VA.isMemLoc());
int Offset = VA.getLocMemOffset();
MemOpChains.push_back(DAG.getNode(XCoreISD::STWSP, dl, MVT::Other,
Chain, Arg,
DAG.getConstant(Offset/4, MVT::i32)));
}
}
// Transform all store nodes into one single node because
// all store nodes are independent of each other.
if (!MemOpChains.empty())
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
&MemOpChains[0], MemOpChains.size());
// Build a sequence of copy-to-reg nodes chained together with token
// chain and flag operands which copy the outgoing args into registers.
// The InFlag in necessary since all emited instructions must be
// stuck together.
SDValue InFlag;
for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first,
RegsToPass[i].second, InFlag);
InFlag = Chain.getValue(1);
}
// If the callee is a GlobalAddress node (quite common, every direct call is)
// turn it into a TargetGlobalAddress node so that legalize doesn't hack it.
// Likewise ExternalSymbol -> TargetExternalSymbol.
if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl, MVT::i32);
else if (ExternalSymbolSDNode *E = dyn_cast<ExternalSymbolSDNode>(Callee))
Callee = DAG.getTargetExternalSymbol(E->getSymbol(), MVT::i32);
// XCoreBranchLink = #chain, #target_address, #opt_in_flags...
// = Chain, Callee, Reg#1, Reg#2, ...
//
// Returns a chain & a flag for retval copy to use.
SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Flag);
SmallVector<SDValue, 8> Ops;
Ops.push_back(Chain);
Ops.push_back(Callee);
// Add argument registers to the end of the list so that they are
// known live into the call.
for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
Ops.push_back(DAG.getRegister(RegsToPass[i].first,
RegsToPass[i].second.getValueType()));
if (InFlag.getNode())
Ops.push_back(InFlag);
Chain = DAG.getNode(XCoreISD::BL, dl, NodeTys, &Ops[0], Ops.size());
InFlag = Chain.getValue(1);
// Create the CALLSEQ_END node.
Chain = DAG.getCALLSEQ_END(Chain,
DAG.getConstant(NumBytes, getPointerTy(), true),
DAG.getConstant(0, getPointerTy(), true),
InFlag);
InFlag = Chain.getValue(1);
// Handle result values, copying them out of physregs into vregs that we
// return.
return LowerCallResult(Chain, InFlag, CallConv, isVarArg,
Ins, dl, DAG, InVals);
}
/// LowerCallResult - Lower the result values of a call into the
/// appropriate copies out of appropriate physical registers.
SDValue
XCoreTargetLowering::LowerCallResult(SDValue Chain, SDValue InFlag,
CallingConv::ID CallConv, bool isVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins,
DebugLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals) const {
// Assign locations to each value returned by this call.
SmallVector<CCValAssign, 16> RVLocs;
CCState CCInfo(CallConv, isVarArg, getTargetMachine(),
RVLocs, *DAG.getContext());
CCInfo.AnalyzeCallResult(Ins, RetCC_XCore);
// Copy all of the result registers out of their specified physreg.
for (unsigned i = 0; i != RVLocs.size(); ++i) {
Chain = DAG.getCopyFromReg(Chain, dl, RVLocs[i].getLocReg(),
RVLocs[i].getValVT(), InFlag).getValue(1);
InFlag = Chain.getValue(2);
InVals.push_back(Chain.getValue(0));
}
return Chain;
}
//===----------------------------------------------------------------------===//
// Formal Arguments Calling Convention Implementation
//===----------------------------------------------------------------------===//
/// XCore formal arguments implementation
SDValue
XCoreTargetLowering::LowerFormalArguments(SDValue Chain,
CallingConv::ID CallConv,
bool isVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins,
DebugLoc dl,
SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals)
const {
switch (CallConv)
{
default:
llvm_unreachable("Unsupported calling convention");
case CallingConv::C:
case CallingConv::Fast:
return LowerCCCArguments(Chain, CallConv, isVarArg,
Ins, dl, DAG, InVals);
}
}
/// LowerCCCArguments - transform physical registers into
/// virtual registers and generate load operations for
/// arguments places on the stack.
/// TODO: sret
SDValue
XCoreTargetLowering::LowerCCCArguments(SDValue Chain,
CallingConv::ID CallConv,
bool isVarArg,
const SmallVectorImpl<ISD::InputArg>
&Ins,
DebugLoc dl,
SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals) const {
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo *MFI = MF.getFrameInfo();
MachineRegisterInfo &RegInfo = MF.getRegInfo();
// Assign locations to all of the incoming arguments.
SmallVector<CCValAssign, 16> ArgLocs;
CCState CCInfo(CallConv, isVarArg, getTargetMachine(),
ArgLocs, *DAG.getContext());
CCInfo.AnalyzeFormalArguments(Ins, CC_XCore);
unsigned StackSlotSize = XCoreFrameInfo::stackSlotSize();
unsigned LRSaveSize = StackSlotSize;
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
CCValAssign &VA = ArgLocs[i];
if (VA.isRegLoc()) {
// Arguments passed in registers
EVT RegVT = VA.getLocVT();
switch (RegVT.getSimpleVT().SimpleTy) {
default:
{
#ifndef NDEBUG
errs() << "LowerFormalArguments Unhandled argument type: "
<< RegVT.getSimpleVT().SimpleTy << "\n";
#endif
llvm_unreachable(0);
}
case MVT::i32:
unsigned VReg = RegInfo.createVirtualRegister(
XCore::GRRegsRegisterClass);
RegInfo.addLiveIn(VA.getLocReg(), VReg);
InVals.push_back(DAG.getCopyFromReg(Chain, dl, VReg, RegVT));
}
} else {
// sanity check
assert(VA.isMemLoc());
// Load the argument to a virtual register
unsigned ObjSize = VA.getLocVT().getSizeInBits()/8;
if (ObjSize > StackSlotSize) {
errs() << "LowerFormalArguments Unhandled argument type: "
<< EVT(VA.getLocVT()).getEVTString()
<< "\n";
}
// Create the frame index object for this incoming parameter...
int FI = MFI->CreateFixedObject(ObjSize,
LRSaveSize + VA.getLocMemOffset(),
true);
// Create the SelectionDAG nodes corresponding to a load
//from this parameter
SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
InVals.push_back(DAG.getLoad(VA.getLocVT(), dl, Chain, FIN,
MachinePointerInfo::getFixedStack(FI),
false, false, 0));
}
}
if (isVarArg) {
/* Argument registers */
static const unsigned ArgRegs[] = {
XCore::R0, XCore::R1, XCore::R2, XCore::R3
};
XCoreFunctionInfo *XFI = MF.getInfo<XCoreFunctionInfo>();
unsigned FirstVAReg = CCInfo.getFirstUnallocated(ArgRegs,
array_lengthof(ArgRegs));
if (FirstVAReg < array_lengthof(ArgRegs)) {
SmallVector<SDValue, 4> MemOps;
int offset = 0;
// Save remaining registers, storing higher register numbers at a higher
// address
for (unsigned i = array_lengthof(ArgRegs) - 1; i >= FirstVAReg; --i) {
// Create a stack slot
int FI = MFI->CreateFixedObject(4, offset, true);
if (i == FirstVAReg) {
XFI->setVarArgsFrameIndex(FI);
}
offset -= StackSlotSize;
SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
// Move argument from phys reg -> virt reg
unsigned VReg = RegInfo.createVirtualRegister(
XCore::GRRegsRegisterClass);
RegInfo.addLiveIn(ArgRegs[i], VReg);
SDValue Val = DAG.getCopyFromReg(Chain, dl, VReg, MVT::i32);
// Move argument from virt reg -> stack
SDValue Store = DAG.getStore(Val.getValue(1), dl, Val, FIN,
MachinePointerInfo(), false, false, 0);
MemOps.push_back(Store);
}
if (!MemOps.empty())
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
&MemOps[0], MemOps.size());
} else {
// This will point to the next argument passed via stack.
XFI->setVarArgsFrameIndex(
MFI->CreateFixedObject(4, LRSaveSize + CCInfo.getNextStackOffset(),
true));
}
}
return Chain;
}
//===----------------------------------------------------------------------===//
// Return Value Calling Convention Implementation
//===----------------------------------------------------------------------===//
bool XCoreTargetLowering::
CanLowerReturn(CallingConv::ID CallConv, bool isVarArg,
const SmallVectorImpl<ISD::OutputArg> &Outs,
LLVMContext &Context) const {
SmallVector<CCValAssign, 16> RVLocs;
CCState CCInfo(CallConv, isVarArg, getTargetMachine(),
RVLocs, Context);
return CCInfo.CheckReturn(Outs, RetCC_XCore);
}
SDValue
XCoreTargetLowering::LowerReturn(SDValue Chain,
CallingConv::ID CallConv, bool isVarArg,
const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<SDValue> &OutVals,
DebugLoc dl, SelectionDAG &DAG) const {
// CCValAssign - represent the assignment of
// the return value to a location
SmallVector<CCValAssign, 16> RVLocs;
// CCState - Info about the registers and stack slot.
CCState CCInfo(CallConv, isVarArg, getTargetMachine(),
RVLocs, *DAG.getContext());
// Analize return values.
CCInfo.AnalyzeReturn(Outs, RetCC_XCore);
// If this is the first return lowered for this function, add
// the regs to the liveout set for the function.
if (DAG.getMachineFunction().getRegInfo().liveout_empty()) {
for (unsigned i = 0; i != RVLocs.size(); ++i)
if (RVLocs[i].isRegLoc())
DAG.getMachineFunction().getRegInfo().addLiveOut(RVLocs[i].getLocReg());
}
SDValue Flag;
// Copy the result values into the output registers.
for (unsigned i = 0; i != RVLocs.size(); ++i) {
CCValAssign &VA = RVLocs[i];
assert(VA.isRegLoc() && "Can only return in registers!");
Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(),
OutVals[i], Flag);
// guarantee that all emitted copies are
// stuck together, avoiding something bad
Flag = Chain.getValue(1);
}
// Return on XCore is always a "retsp 0"
if (Flag.getNode())
return DAG.getNode(XCoreISD::RETSP, dl, MVT::Other,
Chain, DAG.getConstant(0, MVT::i32), Flag);
else // Return Void
return DAG.getNode(XCoreISD::RETSP, dl, MVT::Other,
Chain, DAG.getConstant(0, MVT::i32));
}
//===----------------------------------------------------------------------===//
// Other Lowering Code
//===----------------------------------------------------------------------===//
MachineBasicBlock *
XCoreTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
MachineBasicBlock *BB) const {
const TargetInstrInfo &TII = *getTargetMachine().getInstrInfo();
DebugLoc dl = MI->getDebugLoc();
assert((MI->getOpcode() == XCore::SELECT_CC) &&
"Unexpected instr type to insert");
// To "insert" a SELECT_CC instruction, we actually have to insert the diamond
// control-flow pattern. The incoming instruction knows the destination vreg
// to set, the condition code register to branch on, the true/false values to
// select between, and a branch opcode to use.
const BasicBlock *LLVM_BB = BB->getBasicBlock();
MachineFunction::iterator It = BB;
++It;
// thisMBB:
// ...
// TrueVal = ...
// cmpTY ccX, r1, r2
// bCC copy1MBB
// fallthrough --> copy0MBB
MachineBasicBlock *thisMBB = BB;
MachineFunction *F = BB->getParent();
MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
MachineBasicBlock *sinkMBB = F->CreateMachineBasicBlock(LLVM_BB);
F->insert(It, copy0MBB);
F->insert(It, sinkMBB);
// Transfer the remainder of BB and its successor edges to sinkMBB.
sinkMBB->splice(sinkMBB->begin(), BB,
llvm::next(MachineBasicBlock::iterator(MI)),
BB->end());
sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
// Next, add the true and fallthrough blocks as its successors.
BB->addSuccessor(copy0MBB);
BB->addSuccessor(sinkMBB);
BuildMI(BB, dl, TII.get(XCore::BRFT_lru6))
.addReg(MI->getOperand(1).getReg()).addMBB(sinkMBB);
// copy0MBB:
// %FalseValue = ...
// # fallthrough to sinkMBB
BB = copy0MBB;
// Update machine-CFG edges
BB->addSuccessor(sinkMBB);
// sinkMBB:
// %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
// ...
BB = sinkMBB;
BuildMI(*BB, BB->begin(), dl,
TII.get(XCore::PHI), MI->getOperand(0).getReg())
.addReg(MI->getOperand(3).getReg()).addMBB(copy0MBB)
.addReg(MI->getOperand(2).getReg()).addMBB(thisMBB);
MI->eraseFromParent(); // The pseudo instruction is gone now.
return BB;
}
//===----------------------------------------------------------------------===//
// Target Optimization Hooks
//===----------------------------------------------------------------------===//
SDValue XCoreTargetLowering::PerformDAGCombine(SDNode *N,
DAGCombinerInfo &DCI) const {
SelectionDAG &DAG = DCI.DAG;
DebugLoc dl = N->getDebugLoc();
switch (N->getOpcode()) {
default: break;
case XCoreISD::LADD: {
SDValue N0 = N->getOperand(0);
SDValue N1 = N->getOperand(1);
SDValue N2 = N->getOperand(2);
ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
EVT VT = N0.getValueType();
// canonicalize constant to RHS
if (N0C && !N1C)
return DAG.getNode(XCoreISD::LADD, dl, DAG.getVTList(VT, VT), N1, N0, N2);
// fold (ladd 0, 0, x) -> 0, x & 1
if (N0C && N0C->isNullValue() && N1C && N1C->isNullValue()) {
SDValue Carry = DAG.getConstant(0, VT);
SDValue Result = DAG.getNode(ISD::AND, dl, VT, N2,
DAG.getConstant(1, VT));
SDValue Ops [] = { Carry, Result };
return DAG.getMergeValues(Ops, 2, dl);
}
// fold (ladd x, 0, y) -> 0, add x, y iff carry is unused and y has only the
// low bit set
if (N1C && N1C->isNullValue() && N->hasNUsesOfValue(0, 0)) {
APInt KnownZero, KnownOne;
APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(),
VT.getSizeInBits() - 1);
DAG.ComputeMaskedBits(N2, Mask, KnownZero, KnownOne);
if (KnownZero == Mask) {
SDValue Carry = DAG.getConstant(0, VT);
SDValue Result = DAG.getNode(ISD::ADD, dl, VT, N0, N2);
SDValue Ops [] = { Carry, Result };
return DAG.getMergeValues(Ops, 2, dl);
}
}
}
break;
case XCoreISD::LSUB: {
SDValue N0 = N->getOperand(0);
SDValue N1 = N->getOperand(1);
SDValue N2 = N->getOperand(2);
ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
EVT VT = N0.getValueType();
// fold (lsub 0, 0, x) -> x, -x iff x has only the low bit set
if (N0C && N0C->isNullValue() && N1C && N1C->isNullValue()) {
APInt KnownZero, KnownOne;
APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(),
VT.getSizeInBits() - 1);
DAG.ComputeMaskedBits(N2, Mask, KnownZero, KnownOne);
if (KnownZero == Mask) {
SDValue Borrow = N2;
SDValue Result = DAG.getNode(ISD::SUB, dl, VT,
DAG.getConstant(0, VT), N2);
SDValue Ops [] = { Borrow, Result };
return DAG.getMergeValues(Ops, 2, dl);
}
}
// fold (lsub x, 0, y) -> 0, sub x, y iff borrow is unused and y has only the
// low bit set
if (N1C && N1C->isNullValue() && N->hasNUsesOfValue(0, 0)) {
APInt KnownZero, KnownOne;
APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(),
VT.getSizeInBits() - 1);
DAG.ComputeMaskedBits(N2, Mask, KnownZero, KnownOne);
if (KnownZero == Mask) {
SDValue Borrow = DAG.getConstant(0, VT);
SDValue Result = DAG.getNode(ISD::SUB, dl, VT, N0, N2);
SDValue Ops [] = { Borrow, Result };
return DAG.getMergeValues(Ops, 2, dl);
}
}
}
break;
case XCoreISD::LMUL: {
SDValue N0 = N->getOperand(0);
SDValue N1 = N->getOperand(1);
SDValue N2 = N->getOperand(2);
SDValue N3 = N->getOperand(3);
ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
EVT VT = N0.getValueType();
// Canonicalize multiplicative constant to RHS. If both multiplicative
// operands are constant canonicalize smallest to RHS.
if ((N0C && !N1C) ||
(N0C && N1C && N0C->getZExtValue() < N1C->getZExtValue()))
return DAG.getNode(XCoreISD::LMUL, dl, DAG.getVTList(VT, VT), N1, N0, N2, N3);
// lmul(x, 0, a, b)
if (N1C && N1C->isNullValue()) {
// If the high result is unused fold to add(a, b)
if (N->hasNUsesOfValue(0, 0)) {
SDValue Lo = DAG.getNode(ISD::ADD, dl, VT, N2, N3);
SDValue Ops [] = { Lo, Lo };
return DAG.getMergeValues(Ops, 2, dl);
}
// Otherwise fold to ladd(a, b, 0)
return DAG.getNode(XCoreISD::LADD, dl, DAG.getVTList(VT, VT), N2, N3, N1);
}
}
break;
case ISD::ADD: {
// Fold 32 bit expressions such as add(add(mul(x,y),a),b) ->
// lmul(x, y, a, b). The high result of lmul will be ignored.
// This is only profitable if the intermediate results are unused
// elsewhere.
SDValue Mul0, Mul1, Addend0, Addend1;
if (N->getValueType(0) == MVT::i32 &&
isADDADDMUL(SDValue(N, 0), Mul0, Mul1, Addend0, Addend1, true)) {
SDValue Ignored = DAG.getNode(XCoreISD::LMUL, dl,
DAG.getVTList(MVT::i32, MVT::i32), Mul0,
Mul1, Addend0, Addend1);
SDValue Result(Ignored.getNode(), 1);
return Result;
}
APInt HighMask = APInt::getHighBitsSet(64, 32);
// Fold 64 bit expression such as add(add(mul(x,y),a),b) ->
// lmul(x, y, a, b) if all operands are zero-extended. We do this
// before type legalization as it is messy to match the operands after
// that.
if (N->getValueType(0) == MVT::i64 &&
isADDADDMUL(SDValue(N, 0), Mul0, Mul1, Addend0, Addend1, false) &&
DAG.MaskedValueIsZero(Mul0, HighMask) &&
DAG.MaskedValueIsZero(Mul1, HighMask) &&
DAG.MaskedValueIsZero(Addend0, HighMask) &&
DAG.MaskedValueIsZero(Addend1, HighMask)) {
SDValue Mul0L = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Mul0, DAG.getConstant(0, MVT::i32));
SDValue Mul1L = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Mul1, DAG.getConstant(0, MVT::i32));
SDValue Addend0L = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Addend0, DAG.getConstant(0, MVT::i32));
SDValue Addend1L = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Addend1, DAG.getConstant(0, MVT::i32));
SDValue Hi = DAG.getNode(XCoreISD::LMUL, dl,
DAG.getVTList(MVT::i32, MVT::i32), Mul0L, Mul1L,
Addend0L, Addend1L);
SDValue Lo(Hi.getNode(), 1);
return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
}
}
break;
case ISD::STORE: {
// Replace unaligned store of unaligned load with memmove.
StoreSDNode *ST = cast<StoreSDNode>(N);
if (!DCI.isBeforeLegalize() ||
allowsUnalignedMemoryAccesses(ST->getMemoryVT()) ||
ST->isVolatile() || ST->isIndexed()) {
break;
}
SDValue Chain = ST->getChain();
unsigned StoreBits = ST->getMemoryVT().getStoreSizeInBits();
if (StoreBits % 8) {
break;
}
unsigned ABIAlignment = getTargetData()->getABITypeAlignment(
ST->getMemoryVT().getTypeForEVT(*DCI.DAG.getContext()));
unsigned Alignment = ST->getAlignment();
if (Alignment >= ABIAlignment) {
break;
}
if (LoadSDNode *LD = dyn_cast<LoadSDNode>(ST->getValue())) {
if (LD->hasNUsesOfValue(1, 0) && ST->getMemoryVT() == LD->getMemoryVT() &&
LD->getAlignment() == Alignment &&
!LD->isVolatile() && !LD->isIndexed() &&
Chain.reachesChainWithoutSideEffects(SDValue(LD, 1))) {
return DAG.getMemmove(Chain, dl, ST->getBasePtr(),
LD->getBasePtr(),
DAG.getConstant(StoreBits/8, MVT::i32),
Alignment, false, ST->getPointerInfo(),
LD->getPointerInfo());
}
}
break;
}
}
return SDValue();
}
void XCoreTargetLowering::computeMaskedBitsForTargetNode(const SDValue Op,
const APInt &Mask,
APInt &KnownZero,
APInt &KnownOne,
const SelectionDAG &DAG,
unsigned Depth) const {
KnownZero = KnownOne = APInt(Mask.getBitWidth(), 0);
switch (Op.getOpcode()) {
default: break;
case XCoreISD::LADD:
case XCoreISD::LSUB:
if (Op.getResNo() == 0) {
// Top bits of carry / borrow are clear.
KnownZero = APInt::getHighBitsSet(Mask.getBitWidth(),
Mask.getBitWidth() - 1);
KnownZero &= Mask;
}
break;
}
}
//===----------------------------------------------------------------------===//
// Addressing mode description hooks
//===----------------------------------------------------------------------===//
static inline bool isImmUs(int64_t val)
{
return (val >= 0 && val <= 11);
}
static inline bool isImmUs2(int64_t val)
{
return (val%2 == 0 && isImmUs(val/2));
}
static inline bool isImmUs4(int64_t val)
{
return (val%4 == 0 && isImmUs(val/4));
}
/// isLegalAddressingMode - Return true if the addressing mode represented
/// by AM is legal for this target, for a load/store of the specified type.
bool
XCoreTargetLowering::isLegalAddressingMode(const AddrMode &AM,
const Type *Ty) const {
if (Ty->getTypeID() == Type::VoidTyID)
return AM.Scale == 0 && isImmUs(AM.BaseOffs) && isImmUs4(AM.BaseOffs);
const TargetData *TD = TM.getTargetData();
unsigned Size = TD->getTypeAllocSize(Ty);
if (AM.BaseGV) {
return Size >= 4 && !AM.HasBaseReg && AM.Scale == 0 &&
AM.BaseOffs%4 == 0;
}
switch (Size) {
case 1:
// reg + imm
if (AM.Scale == 0) {
return isImmUs(AM.BaseOffs);
}
// reg + reg
return AM.Scale == 1 && AM.BaseOffs == 0;
case 2:
case 3:
// reg + imm
if (AM.Scale == 0) {
return isImmUs2(AM.BaseOffs);
}
// reg + reg<<1
return AM.Scale == 2 && AM.BaseOffs == 0;
default:
// reg + imm
if (AM.Scale == 0) {
return isImmUs4(AM.BaseOffs);
}
// reg + reg<<2
return AM.Scale == 4 && AM.BaseOffs == 0;
}
return false;
}
//===----------------------------------------------------------------------===//
// XCore Inline Assembly Support
//===----------------------------------------------------------------------===//
std::vector<unsigned> XCoreTargetLowering::
getRegClassForInlineAsmConstraint(const std::string &Constraint,
EVT VT) const
{
if (Constraint.size() != 1)
return std::vector<unsigned>();
switch (Constraint[0]) {
default : break;
case 'r':
return make_vector<unsigned>(XCore::R0, XCore::R1, XCore::R2,
XCore::R3, XCore::R4, XCore::R5,
XCore::R6, XCore::R7, XCore::R8,
XCore::R9, XCore::R10, XCore::R11, 0);
break;
}
return std::vector<unsigned>();
}