llvm-6502/lib/Target/X86/X86ISelLowering.cpp
2006-03-17 17:27:47 +00:00

2243 lines
85 KiB
C++

//===-- X86ISelLowering.h - X86 DAG Lowering Interface ----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Chris Lattner and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the interfaces that X86 uses to lower LLVM code into a
// selection DAG.
//
//===----------------------------------------------------------------------===//
#include "X86.h"
#include "X86InstrBuilder.h"
#include "X86ISelLowering.h"
#include "X86TargetMachine.h"
#include "llvm/CallingConv.h"
#include "llvm/Constants.h"
#include "llvm/Function.h"
#include "llvm/ADT/VectorExtras.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/SSARegMap.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
// FIXME: temporary.
#include "llvm/Support/CommandLine.h"
static cl::opt<bool> EnableFastCC("enable-x86-fastcc", cl::Hidden,
cl::desc("Enable fastcc on X86"));
X86TargetLowering::X86TargetLowering(TargetMachine &TM)
: TargetLowering(TM) {
Subtarget = &TM.getSubtarget<X86Subtarget>();
X86ScalarSSE = Subtarget->hasSSE2();
// Set up the TargetLowering object.
// X86 is weird, it always uses i8 for shift amounts and setcc results.
setShiftAmountType(MVT::i8);
setSetCCResultType(MVT::i8);
setSetCCResultContents(ZeroOrOneSetCCResult);
setSchedulingPreference(SchedulingForRegPressure);
setShiftAmountFlavor(Mask); // shl X, 32 == shl X, 0
setStackPointerRegisterToSaveRestore(X86::ESP);
// Add legal addressing mode scale values.
addLegalAddressScale(8);
addLegalAddressScale(4);
addLegalAddressScale(2);
// Enter the ones which require both scale + index last. These are more
// expensive.
addLegalAddressScale(9);
addLegalAddressScale(5);
addLegalAddressScale(3);
// Set up the register classes.
addRegisterClass(MVT::i8, X86::R8RegisterClass);
addRegisterClass(MVT::i16, X86::R16RegisterClass);
addRegisterClass(MVT::i32, X86::R32RegisterClass);
// Promote all UINT_TO_FP to larger SINT_TO_FP's, as X86 doesn't have this
// operation.
setOperationAction(ISD::UINT_TO_FP , MVT::i1 , Promote);
setOperationAction(ISD::UINT_TO_FP , MVT::i8 , Promote);
setOperationAction(ISD::UINT_TO_FP , MVT::i16 , Promote);
if (X86ScalarSSE)
// No SSE i64 SINT_TO_FP, so expand i32 UINT_TO_FP instead.
setOperationAction(ISD::UINT_TO_FP , MVT::i32 , Expand);
else
setOperationAction(ISD::UINT_TO_FP , MVT::i32 , Promote);
// Promote i1/i8 SINT_TO_FP to larger SINT_TO_FP's, as X86 doesn't have
// this operation.
setOperationAction(ISD::SINT_TO_FP , MVT::i1 , Promote);
setOperationAction(ISD::SINT_TO_FP , MVT::i8 , Promote);
// SSE has no i16 to fp conversion, only i32
if (X86ScalarSSE)
setOperationAction(ISD::SINT_TO_FP , MVT::i16 , Promote);
else {
setOperationAction(ISD::SINT_TO_FP , MVT::i16 , Custom);
setOperationAction(ISD::SINT_TO_FP , MVT::i32 , Custom);
}
// We can handle SINT_TO_FP and FP_TO_SINT from/to i64 even though i64
// isn't legal.
setOperationAction(ISD::SINT_TO_FP , MVT::i64 , Custom);
setOperationAction(ISD::FP_TO_SINT , MVT::i64 , Custom);
// Promote i1/i8 FP_TO_SINT to larger FP_TO_SINTS's, as X86 doesn't have
// this operation.
setOperationAction(ISD::FP_TO_SINT , MVT::i1 , Promote);
setOperationAction(ISD::FP_TO_SINT , MVT::i8 , Promote);
if (X86ScalarSSE) {
setOperationAction(ISD::FP_TO_SINT , MVT::i16 , Promote);
} else {
setOperationAction(ISD::FP_TO_SINT , MVT::i16 , Custom);
setOperationAction(ISD::FP_TO_SINT , MVT::i32 , Custom);
}
// Handle FP_TO_UINT by promoting the destination to a larger signed
// conversion.
setOperationAction(ISD::FP_TO_UINT , MVT::i1 , Promote);
setOperationAction(ISD::FP_TO_UINT , MVT::i8 , Promote);
setOperationAction(ISD::FP_TO_UINT , MVT::i16 , Promote);
if (X86ScalarSSE && !Subtarget->hasSSE3())
// Expand FP_TO_UINT into a select.
// FIXME: We would like to use a Custom expander here eventually to do
// the optimal thing for SSE vs. the default expansion in the legalizer.
setOperationAction(ISD::FP_TO_UINT , MVT::i32 , Expand);
else
// With SSE3 we can use fisttpll to convert to a signed i64.
setOperationAction(ISD::FP_TO_UINT , MVT::i32 , Promote);
setOperationAction(ISD::BIT_CONVERT , MVT::f32 , Expand);
setOperationAction(ISD::BIT_CONVERT , MVT::i32 , Expand);
setOperationAction(ISD::BRCOND , MVT::Other, Custom);
setOperationAction(ISD::BR_CC , MVT::Other, Expand);
setOperationAction(ISD::SELECT_CC , MVT::Other, Expand);
setOperationAction(ISD::MEMMOVE , MVT::Other, Expand);
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16 , Expand);
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8 , Expand);
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1 , Expand);
setOperationAction(ISD::FP_ROUND_INREG , MVT::f32 , Expand);
setOperationAction(ISD::SEXTLOAD , MVT::i1 , Expand);
setOperationAction(ISD::FREM , MVT::f64 , Expand);
setOperationAction(ISD::CTPOP , MVT::i8 , Expand);
setOperationAction(ISD::CTTZ , MVT::i8 , Expand);
setOperationAction(ISD::CTLZ , MVT::i8 , Expand);
setOperationAction(ISD::CTPOP , MVT::i16 , Expand);
setOperationAction(ISD::CTTZ , MVT::i16 , Expand);
setOperationAction(ISD::CTLZ , MVT::i16 , Expand);
setOperationAction(ISD::CTPOP , MVT::i32 , Expand);
setOperationAction(ISD::CTTZ , MVT::i32 , Expand);
setOperationAction(ISD::CTLZ , MVT::i32 , Expand);
setOperationAction(ISD::READCYCLECOUNTER , MVT::i64 , Custom);
setOperationAction(ISD::BSWAP , MVT::i16 , Expand);
// These should be promoted to a larger select which is supported.
setOperationAction(ISD::SELECT , MVT::i1 , Promote);
setOperationAction(ISD::SELECT , MVT::i8 , Promote);
// X86 wants to expand cmov itself.
setOperationAction(ISD::SELECT , MVT::i16 , Custom);
setOperationAction(ISD::SELECT , MVT::i32 , Custom);
setOperationAction(ISD::SELECT , MVT::f32 , Custom);
setOperationAction(ISD::SELECT , MVT::f64 , Custom);
setOperationAction(ISD::SETCC , MVT::i8 , Custom);
setOperationAction(ISD::SETCC , MVT::i16 , Custom);
setOperationAction(ISD::SETCC , MVT::i32 , Custom);
setOperationAction(ISD::SETCC , MVT::f32 , Custom);
setOperationAction(ISD::SETCC , MVT::f64 , Custom);
// X86 ret instruction may pop stack.
setOperationAction(ISD::RET , MVT::Other, Custom);
// Darwin ABI issue.
setOperationAction(ISD::ConstantPool , MVT::i32 , Custom);
setOperationAction(ISD::GlobalAddress , MVT::i32 , Custom);
setOperationAction(ISD::ExternalSymbol , MVT::i32 , Custom);
// 64-bit addm sub, shl, sra, srl (iff 32-bit x86)
setOperationAction(ISD::SHL_PARTS , MVT::i32 , Custom);
setOperationAction(ISD::SRA_PARTS , MVT::i32 , Custom);
setOperationAction(ISD::SRL_PARTS , MVT::i32 , Custom);
// X86 wants to expand memset / memcpy itself.
setOperationAction(ISD::MEMSET , MVT::Other, Custom);
setOperationAction(ISD::MEMCPY , MVT::Other, Custom);
// We don't have line number support yet.
setOperationAction(ISD::LOCATION, MVT::Other, Expand);
setOperationAction(ISD::DEBUG_LOC, MVT::Other, Expand);
// FIXME - use subtarget debug flags
if (!TM.getSubtarget<X86Subtarget>().isTargetDarwin())
setOperationAction(ISD::DEBUG_LABEL, MVT::Other, Expand);
// VASTART needs to be custom lowered to use the VarArgsFrameIndex
setOperationAction(ISD::VASTART , MVT::Other, Custom);
// Use the default implementation.
setOperationAction(ISD::VAARG , MVT::Other, Expand);
setOperationAction(ISD::VACOPY , MVT::Other, Expand);
setOperationAction(ISD::VAEND , MVT::Other, Expand);
setOperationAction(ISD::STACKSAVE, MVT::Other, Expand);
setOperationAction(ISD::STACKRESTORE, MVT::Other, Expand);
setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32 , Expand);
setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
if (X86ScalarSSE) {
// Set up the FP register classes.
addRegisterClass(MVT::f32, X86::FR32RegisterClass);
addRegisterClass(MVT::f64, X86::FR64RegisterClass);
// SSE has no load+extend ops
setOperationAction(ISD::EXTLOAD, MVT::f32, Expand);
setOperationAction(ISD::ZEXTLOAD, MVT::f32, Expand);
// Use ANDPD to simulate FABS.
setOperationAction(ISD::FABS , MVT::f64, Custom);
setOperationAction(ISD::FABS , MVT::f32, Custom);
// Use XORP to simulate FNEG.
setOperationAction(ISD::FNEG , MVT::f64, Custom);
setOperationAction(ISD::FNEG , MVT::f32, Custom);
// We don't support sin/cos/fmod
setOperationAction(ISD::FSIN , MVT::f64, Expand);
setOperationAction(ISD::FCOS , MVT::f64, Expand);
setOperationAction(ISD::FREM , MVT::f64, Expand);
setOperationAction(ISD::FSIN , MVT::f32, Expand);
setOperationAction(ISD::FCOS , MVT::f32, Expand);
setOperationAction(ISD::FREM , MVT::f32, Expand);
// Expand FP immediates into loads from the stack, except for the special
// cases we handle.
setOperationAction(ISD::ConstantFP, MVT::f64, Expand);
setOperationAction(ISD::ConstantFP, MVT::f32, Expand);
addLegalFPImmediate(+0.0); // xorps / xorpd
} else {
// Set up the FP register classes.
addRegisterClass(MVT::f64, X86::RFPRegisterClass);
setOperationAction(ISD::UNDEF, MVT::f64, Expand);
if (!UnsafeFPMath) {
setOperationAction(ISD::FSIN , MVT::f64 , Expand);
setOperationAction(ISD::FCOS , MVT::f64 , Expand);
}
setOperationAction(ISD::ConstantFP, MVT::f64, Expand);
addLegalFPImmediate(+0.0); // FLD0
addLegalFPImmediate(+1.0); // FLD1
addLegalFPImmediate(-0.0); // FLD0/FCHS
addLegalFPImmediate(-1.0); // FLD1/FCHS
}
// First set operation action for all vector types to expand. Then we
// will selectively turn on ones that can be effectively codegen'd.
for (unsigned VT = (unsigned)MVT::Vector + 1;
VT != (unsigned)MVT::LAST_VALUETYPE; VT++) {
setOperationAction(ISD::ADD , (MVT::ValueType)VT, Expand);
setOperationAction(ISD::SUB , (MVT::ValueType)VT, Expand);
setOperationAction(ISD::MUL , (MVT::ValueType)VT, Expand);
setOperationAction(ISD::LOAD, (MVT::ValueType)VT, Expand);
}
if (TM.getSubtarget<X86Subtarget>().hasMMX()) {
addRegisterClass(MVT::v8i8, X86::VR64RegisterClass);
addRegisterClass(MVT::v4i16, X86::VR64RegisterClass);
addRegisterClass(MVT::v2i32, X86::VR64RegisterClass);
// FIXME: add MMX packed arithmetics
setOperationAction(ISD::ConstantVec, MVT::v8i8, Expand);
setOperationAction(ISD::ConstantVec, MVT::v4i16, Expand);
setOperationAction(ISD::ConstantVec, MVT::v2i32, Expand);
}
if (TM.getSubtarget<X86Subtarget>().hasSSE1()) {
addRegisterClass(MVT::v4f32, X86::VR128RegisterClass);
setOperationAction(ISD::ADD , MVT::v4f32, Legal);
setOperationAction(ISD::SUB , MVT::v4f32, Legal);
setOperationAction(ISD::MUL , MVT::v4f32, Legal);
setOperationAction(ISD::LOAD , MVT::v4f32, Legal);
setOperationAction(ISD::ConstantVec, MVT::v4f32, Expand);
}
if (TM.getSubtarget<X86Subtarget>().hasSSE2()) {
addRegisterClass(MVT::v2f64, X86::VR128RegisterClass);
addRegisterClass(MVT::v16i8, X86::VR128RegisterClass);
addRegisterClass(MVT::v8i16, X86::VR128RegisterClass);
addRegisterClass(MVT::v4i32, X86::VR128RegisterClass);
addRegisterClass(MVT::v2i64, X86::VR128RegisterClass);
setOperationAction(ISD::ADD , MVT::v2f64, Legal);
setOperationAction(ISD::SUB , MVT::v2f64, Legal);
setOperationAction(ISD::MUL , MVT::v2f64, Legal);
setOperationAction(ISD::LOAD , MVT::v2f64, Legal);
setOperationAction(ISD::ConstantVec, MVT::v2f64, Expand);
setOperationAction(ISD::ConstantVec, MVT::v16i8, Expand);
setOperationAction(ISD::ConstantVec, MVT::v8i16, Expand);
setOperationAction(ISD::ConstantVec, MVT::v4i32, Expand);
setOperationAction(ISD::ConstantVec, MVT::v2i64, Expand);
}
computeRegisterProperties();
// FIXME: These should be based on subtarget info. Plus, the values should
// be smaller when we are in optimizing for size mode.
maxStoresPerMemset = 16; // For %llvm.memset -> sequence of stores
maxStoresPerMemcpy = 16; // For %llvm.memcpy -> sequence of stores
maxStoresPerMemmove = 16; // For %llvm.memmove -> sequence of stores
allowUnalignedMemoryAccesses = true; // x86 supports it!
}
std::vector<SDOperand>
X86TargetLowering::LowerArguments(Function &F, SelectionDAG &DAG) {
if (F.getCallingConv() == CallingConv::Fast && EnableFastCC)
return LowerFastCCArguments(F, DAG);
return LowerCCCArguments(F, DAG);
}
std::pair<SDOperand, SDOperand>
X86TargetLowering::LowerCallTo(SDOperand Chain, const Type *RetTy,
bool isVarArg, unsigned CallingConv,
bool isTailCall,
SDOperand Callee, ArgListTy &Args,
SelectionDAG &DAG) {
assert((!isVarArg || CallingConv == CallingConv::C) &&
"Only C takes varargs!");
// 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.
if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
Callee = DAG.getTargetGlobalAddress(G->getGlobal(), getPointerTy());
else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee))
Callee = DAG.getTargetExternalSymbol(S->getSymbol(), getPointerTy());
if (CallingConv == CallingConv::Fast && EnableFastCC)
return LowerFastCCCallTo(Chain, RetTy, isTailCall, Callee, Args, DAG);
return LowerCCCCallTo(Chain, RetTy, isVarArg, isTailCall, Callee, Args, DAG);
}
//===----------------------------------------------------------------------===//
// C Calling Convention implementation
//===----------------------------------------------------------------------===//
std::vector<SDOperand>
X86TargetLowering::LowerCCCArguments(Function &F, SelectionDAG &DAG) {
std::vector<SDOperand> ArgValues;
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo *MFI = MF.getFrameInfo();
// Add DAG nodes to load the arguments... On entry to a function on the X86,
// the stack frame looks like this:
//
// [ESP] -- return address
// [ESP + 4] -- first argument (leftmost lexically)
// [ESP + 8] -- second argument, if first argument is four bytes in size
// ...
//
unsigned ArgOffset = 0; // Frame mechanisms handle retaddr slot
for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E; ++I) {
MVT::ValueType ObjectVT = getValueType(I->getType());
unsigned ArgIncrement = 4;
unsigned ObjSize;
switch (ObjectVT) {
default: assert(0 && "Unhandled argument type!");
case MVT::i1:
case MVT::i8: ObjSize = 1; break;
case MVT::i16: ObjSize = 2; break;
case MVT::i32: ObjSize = 4; break;
case MVT::i64: ObjSize = ArgIncrement = 8; break;
case MVT::f32: ObjSize = 4; break;
case MVT::f64: ObjSize = ArgIncrement = 8; break;
}
// Create the frame index object for this incoming parameter...
int FI = MFI->CreateFixedObject(ObjSize, ArgOffset);
// Create the SelectionDAG nodes corresponding to a load from this parameter
SDOperand FIN = DAG.getFrameIndex(FI, MVT::i32);
// Don't codegen dead arguments. FIXME: remove this check when we can nuke
// dead loads.
SDOperand ArgValue;
if (!I->use_empty())
ArgValue = DAG.getLoad(ObjectVT, DAG.getEntryNode(), FIN,
DAG.getSrcValue(NULL));
else {
if (MVT::isInteger(ObjectVT))
ArgValue = DAG.getConstant(0, ObjectVT);
else
ArgValue = DAG.getConstantFP(0, ObjectVT);
}
ArgValues.push_back(ArgValue);
ArgOffset += ArgIncrement; // Move on to the next argument...
}
// If the function takes variable number of arguments, make a frame index for
// the start of the first vararg value... for expansion of llvm.va_start.
if (F.isVarArg())
VarArgsFrameIndex = MFI->CreateFixedObject(1, ArgOffset);
ReturnAddrIndex = 0; // No return address slot generated yet.
BytesToPopOnReturn = 0; // Callee pops nothing.
BytesCallerReserves = ArgOffset;
// Finally, inform the code generator which regs we return values in.
switch (getValueType(F.getReturnType())) {
default: assert(0 && "Unknown type!");
case MVT::isVoid: break;
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
MF.addLiveOut(X86::EAX);
break;
case MVT::i64:
MF.addLiveOut(X86::EAX);
MF.addLiveOut(X86::EDX);
break;
case MVT::f32:
case MVT::f64:
MF.addLiveOut(X86::ST0);
break;
}
return ArgValues;
}
std::pair<SDOperand, SDOperand>
X86TargetLowering::LowerCCCCallTo(SDOperand Chain, const Type *RetTy,
bool isVarArg, bool isTailCall,
SDOperand Callee, ArgListTy &Args,
SelectionDAG &DAG) {
// Count how many bytes are to be pushed on the stack.
unsigned NumBytes = 0;
if (Args.empty()) {
// Save zero bytes.
Chain = DAG.getCALLSEQ_START(Chain, DAG.getConstant(0, getPointerTy()));
} else {
for (unsigned i = 0, e = Args.size(); i != e; ++i)
switch (getValueType(Args[i].second)) {
default: assert(0 && "Unknown value type!");
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
case MVT::f32:
NumBytes += 4;
break;
case MVT::i64:
case MVT::f64:
NumBytes += 8;
break;
}
Chain = DAG.getCALLSEQ_START(Chain,
DAG.getConstant(NumBytes, getPointerTy()));
// Arguments go on the stack in reverse order, as specified by the ABI.
unsigned ArgOffset = 0;
SDOperand StackPtr = DAG.getRegister(X86::ESP, MVT::i32);
std::vector<SDOperand> Stores;
for (unsigned i = 0, e = Args.size(); i != e; ++i) {
SDOperand PtrOff = DAG.getConstant(ArgOffset, getPointerTy());
PtrOff = DAG.getNode(ISD::ADD, MVT::i32, StackPtr, PtrOff);
switch (getValueType(Args[i].second)) {
default: assert(0 && "Unexpected ValueType for argument!");
case MVT::i1:
case MVT::i8:
case MVT::i16:
// Promote the integer to 32 bits. If the input type is signed use a
// sign extend, otherwise use a zero extend.
if (Args[i].second->isSigned())
Args[i].first =DAG.getNode(ISD::SIGN_EXTEND, MVT::i32, Args[i].first);
else
Args[i].first =DAG.getNode(ISD::ZERO_EXTEND, MVT::i32, Args[i].first);
// FALL THROUGH
case MVT::i32:
case MVT::f32:
Stores.push_back(DAG.getNode(ISD::STORE, MVT::Other, Chain,
Args[i].first, PtrOff,
DAG.getSrcValue(NULL)));
ArgOffset += 4;
break;
case MVT::i64:
case MVT::f64:
Stores.push_back(DAG.getNode(ISD::STORE, MVT::Other, Chain,
Args[i].first, PtrOff,
DAG.getSrcValue(NULL)));
ArgOffset += 8;
break;
}
}
Chain = DAG.getNode(ISD::TokenFactor, MVT::Other, Stores);
}
std::vector<MVT::ValueType> RetVals;
MVT::ValueType RetTyVT = getValueType(RetTy);
RetVals.push_back(MVT::Other);
// The result values produced have to be legal. Promote the result.
switch (RetTyVT) {
case MVT::isVoid: break;
default:
RetVals.push_back(RetTyVT);
break;
case MVT::i1:
case MVT::i8:
case MVT::i16:
RetVals.push_back(MVT::i32);
break;
case MVT::f32:
if (X86ScalarSSE)
RetVals.push_back(MVT::f32);
else
RetVals.push_back(MVT::f64);
break;
case MVT::i64:
RetVals.push_back(MVT::i32);
RetVals.push_back(MVT::i32);
break;
}
std::vector<MVT::ValueType> NodeTys;
NodeTys.push_back(MVT::Other); // Returns a chain
NodeTys.push_back(MVT::Flag); // Returns a flag for retval copy to use.
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(Callee);
// FIXME: Do not generate X86ISD::TAILCALL for now.
Chain = DAG.getNode(X86ISD::CALL, NodeTys, Ops);
SDOperand InFlag = Chain.getValue(1);
NodeTys.clear();
NodeTys.push_back(MVT::Other); // Returns a chain
NodeTys.push_back(MVT::Flag); // Returns a flag for retval copy to use.
Ops.clear();
Ops.push_back(Chain);
Ops.push_back(DAG.getConstant(NumBytes, getPointerTy()));
Ops.push_back(DAG.getConstant(0, getPointerTy()));
Ops.push_back(InFlag);
Chain = DAG.getNode(ISD::CALLSEQ_END, NodeTys, Ops);
InFlag = Chain.getValue(1);
SDOperand RetVal;
if (RetTyVT != MVT::isVoid) {
switch (RetTyVT) {
default: assert(0 && "Unknown value type to return!");
case MVT::i1:
case MVT::i8:
RetVal = DAG.getCopyFromReg(Chain, X86::AL, MVT::i8, InFlag);
Chain = RetVal.getValue(1);
if (RetTyVT == MVT::i1)
RetVal = DAG.getNode(ISD::TRUNCATE, MVT::i1, RetVal);
break;
case MVT::i16:
RetVal = DAG.getCopyFromReg(Chain, X86::AX, MVT::i16, InFlag);
Chain = RetVal.getValue(1);
break;
case MVT::i32:
RetVal = DAG.getCopyFromReg(Chain, X86::EAX, MVT::i32, InFlag);
Chain = RetVal.getValue(1);
break;
case MVT::i64: {
SDOperand Lo = DAG.getCopyFromReg(Chain, X86::EAX, MVT::i32, InFlag);
SDOperand Hi = DAG.getCopyFromReg(Lo.getValue(1), X86::EDX, MVT::i32,
Lo.getValue(2));
RetVal = DAG.getNode(ISD::BUILD_PAIR, MVT::i64, Lo, Hi);
Chain = Hi.getValue(1);
break;
}
case MVT::f32:
case MVT::f64: {
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::f64);
Tys.push_back(MVT::Other);
Tys.push_back(MVT::Flag);
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(InFlag);
RetVal = DAG.getNode(X86ISD::FP_GET_RESULT, Tys, Ops);
Chain = RetVal.getValue(1);
InFlag = RetVal.getValue(2);
if (X86ScalarSSE) {
// FIXME: Currently the FST is flagged to the FP_GET_RESULT. This
// shouldn't be necessary except that RFP cannot be live across
// multiple blocks. When stackifier is fixed, they can be uncoupled.
MachineFunction &MF = DAG.getMachineFunction();
int SSFI = MF.getFrameInfo()->CreateStackObject(8, 8);
SDOperand StackSlot = DAG.getFrameIndex(SSFI, getPointerTy());
Tys.clear();
Tys.push_back(MVT::Other);
Ops.clear();
Ops.push_back(Chain);
Ops.push_back(RetVal);
Ops.push_back(StackSlot);
Ops.push_back(DAG.getValueType(RetTyVT));
Ops.push_back(InFlag);
Chain = DAG.getNode(X86ISD::FST, Tys, Ops);
RetVal = DAG.getLoad(RetTyVT, Chain, StackSlot,
DAG.getSrcValue(NULL));
Chain = RetVal.getValue(1);
}
if (RetTyVT == MVT::f32 && !X86ScalarSSE)
// FIXME: we would really like to remember that this FP_ROUND
// operation is okay to eliminate if we allow excess FP precision.
RetVal = DAG.getNode(ISD::FP_ROUND, MVT::f32, RetVal);
break;
}
}
}
return std::make_pair(RetVal, Chain);
}
//===----------------------------------------------------------------------===//
// Fast Calling Convention implementation
//===----------------------------------------------------------------------===//
//
// The X86 'fast' calling convention passes up to two integer arguments in
// registers (an appropriate portion of EAX/EDX), passes arguments in C order,
// and requires that the callee pop its arguments off the stack (allowing proper
// tail calls), and has the same return value conventions as C calling convs.
//
// This calling convention always arranges for the callee pop value to be 8n+4
// bytes, which is needed for tail recursion elimination and stack alignment
// reasons.
//
// Note that this can be enhanced in the future to pass fp vals in registers
// (when we have a global fp allocator) and do other tricks.
//
/// AddLiveIn - This helper function adds the specified physical register to the
/// MachineFunction as a live in value. It also creates a corresponding virtual
/// register for it.
static unsigned AddLiveIn(MachineFunction &MF, unsigned PReg,
TargetRegisterClass *RC) {
assert(RC->contains(PReg) && "Not the correct regclass!");
unsigned VReg = MF.getSSARegMap()->createVirtualRegister(RC);
MF.addLiveIn(PReg, VReg);
return VReg;
}
// FASTCC_NUM_INT_ARGS_INREGS - This is the max number of integer arguments
// to pass in registers. 0 is none, 1 is is "use EAX", 2 is "use EAX and
// EDX". Anything more is illegal.
//
// FIXME: The linscan register allocator currently has problem with
// coallescing. At the time of this writing, whenever it decides to coallesce
// a physreg with a virtreg, this increases the size of the physreg's live
// range, and the live range cannot ever be reduced. This causes problems if
// too many physregs are coalleced with virtregs, which can cause the register
// allocator to wedge itself.
//
// This code triggers this problem more often if we pass args in registers,
// so disable it until this is fixed.
//
// NOTE: this isn't marked const, so that GCC doesn't emit annoying warnings
// about code being dead.
//
static unsigned FASTCC_NUM_INT_ARGS_INREGS = 0;
std::vector<SDOperand>
X86TargetLowering::LowerFastCCArguments(Function &F, SelectionDAG &DAG) {
std::vector<SDOperand> ArgValues;
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo *MFI = MF.getFrameInfo();
// Add DAG nodes to load the arguments... On entry to a function the stack
// frame looks like this:
//
// [ESP] -- return address
// [ESP + 4] -- first nonreg argument (leftmost lexically)
// [ESP + 8] -- second nonreg argument, if first argument is 4 bytes in size
// ...
unsigned ArgOffset = 0; // Frame mechanisms handle retaddr slot
// Keep track of the number of integer regs passed so far. This can be either
// 0 (neither EAX or EDX used), 1 (EAX is used) or 2 (EAX and EDX are both
// used).
unsigned NumIntRegs = 0;
for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E; ++I) {
MVT::ValueType ObjectVT = getValueType(I->getType());
unsigned ArgIncrement = 4;
unsigned ObjSize = 0;
SDOperand ArgValue;
switch (ObjectVT) {
default: assert(0 && "Unhandled argument type!");
case MVT::i1:
case MVT::i8:
if (NumIntRegs < FASTCC_NUM_INT_ARGS_INREGS) {
if (!I->use_empty()) {
unsigned VReg = AddLiveIn(MF, NumIntRegs ? X86::DL : X86::AL,
X86::R8RegisterClass);
ArgValue = DAG.getCopyFromReg(DAG.getRoot(), VReg, MVT::i8);
DAG.setRoot(ArgValue.getValue(1));
if (ObjectVT == MVT::i1)
// FIXME: Should insert a assertzext here.
ArgValue = DAG.getNode(ISD::TRUNCATE, MVT::i1, ArgValue);
}
++NumIntRegs;
break;
}
ObjSize = 1;
break;
case MVT::i16:
if (NumIntRegs < FASTCC_NUM_INT_ARGS_INREGS) {
if (!I->use_empty()) {
unsigned VReg = AddLiveIn(MF, NumIntRegs ? X86::DX : X86::AX,
X86::R16RegisterClass);
ArgValue = DAG.getCopyFromReg(DAG.getRoot(), VReg, MVT::i16);
DAG.setRoot(ArgValue.getValue(1));
}
++NumIntRegs;
break;
}
ObjSize = 2;
break;
case MVT::i32:
if (NumIntRegs < FASTCC_NUM_INT_ARGS_INREGS) {
if (!I->use_empty()) {
unsigned VReg = AddLiveIn(MF, NumIntRegs ? X86::EDX : X86::EAX,
X86::R32RegisterClass);
ArgValue = DAG.getCopyFromReg(DAG.getRoot(), VReg, MVT::i32);
DAG.setRoot(ArgValue.getValue(1));
}
++NumIntRegs;
break;
}
ObjSize = 4;
break;
case MVT::i64:
if (NumIntRegs+2 <= FASTCC_NUM_INT_ARGS_INREGS) {
if (!I->use_empty()) {
unsigned BotReg = AddLiveIn(MF, X86::EAX, X86::R32RegisterClass);
unsigned TopReg = AddLiveIn(MF, X86::EDX, X86::R32RegisterClass);
SDOperand Low = DAG.getCopyFromReg(DAG.getRoot(), BotReg, MVT::i32);
SDOperand Hi = DAG.getCopyFromReg(Low.getValue(1), TopReg, MVT::i32);
DAG.setRoot(Hi.getValue(1));
ArgValue = DAG.getNode(ISD::BUILD_PAIR, MVT::i64, Low, Hi);
}
NumIntRegs += 2;
break;
} else if (NumIntRegs+1 <= FASTCC_NUM_INT_ARGS_INREGS) {
if (!I->use_empty()) {
unsigned BotReg = AddLiveIn(MF, X86::EDX, X86::R32RegisterClass);
SDOperand Low = DAG.getCopyFromReg(DAG.getRoot(), BotReg, MVT::i32);
DAG.setRoot(Low.getValue(1));
// Load the high part from memory.
// Create the frame index object for this incoming parameter...
int FI = MFI->CreateFixedObject(4, ArgOffset);
SDOperand FIN = DAG.getFrameIndex(FI, MVT::i32);
SDOperand Hi = DAG.getLoad(MVT::i32, DAG.getEntryNode(), FIN,
DAG.getSrcValue(NULL));
ArgValue = DAG.getNode(ISD::BUILD_PAIR, MVT::i64, Low, Hi);
}
ArgOffset += 4;
NumIntRegs = FASTCC_NUM_INT_ARGS_INREGS;
break;
}
ObjSize = ArgIncrement = 8;
break;
case MVT::f32: ObjSize = 4; break;
case MVT::f64: ObjSize = ArgIncrement = 8; break;
}
// Don't codegen dead arguments. FIXME: remove this check when we can nuke
// dead loads.
if (ObjSize && !I->use_empty()) {
// Create the frame index object for this incoming parameter...
int FI = MFI->CreateFixedObject(ObjSize, ArgOffset);
// Create the SelectionDAG nodes corresponding to a load from this
// parameter.
SDOperand FIN = DAG.getFrameIndex(FI, MVT::i32);
ArgValue = DAG.getLoad(ObjectVT, DAG.getEntryNode(), FIN,
DAG.getSrcValue(NULL));
} else if (ArgValue.Val == 0) {
if (MVT::isInteger(ObjectVT))
ArgValue = DAG.getConstant(0, ObjectVT);
else
ArgValue = DAG.getConstantFP(0, ObjectVT);
}
ArgValues.push_back(ArgValue);
if (ObjSize)
ArgOffset += ArgIncrement; // Move on to the next argument.
}
// Make sure the instruction takes 8n+4 bytes to make sure the start of the
// arguments and the arguments after the retaddr has been pushed are aligned.
if ((ArgOffset & 7) == 0)
ArgOffset += 4;
VarArgsFrameIndex = 0xAAAAAAA; // fastcc functions can't have varargs.
ReturnAddrIndex = 0; // No return address slot generated yet.
BytesToPopOnReturn = ArgOffset; // Callee pops all stack arguments.
BytesCallerReserves = 0;
// Finally, inform the code generator which regs we return values in.
switch (getValueType(F.getReturnType())) {
default: assert(0 && "Unknown type!");
case MVT::isVoid: break;
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
MF.addLiveOut(X86::EAX);
break;
case MVT::i64:
MF.addLiveOut(X86::EAX);
MF.addLiveOut(X86::EDX);
break;
case MVT::f32:
case MVT::f64:
MF.addLiveOut(X86::ST0);
break;
}
return ArgValues;
}
std::pair<SDOperand, SDOperand>
X86TargetLowering::LowerFastCCCallTo(SDOperand Chain, const Type *RetTy,
bool isTailCall, SDOperand Callee,
ArgListTy &Args, SelectionDAG &DAG) {
// Count how many bytes are to be pushed on the stack.
unsigned NumBytes = 0;
// Keep track of the number of integer regs passed so far. This can be either
// 0 (neither EAX or EDX used), 1 (EAX is used) or 2 (EAX and EDX are both
// used).
unsigned NumIntRegs = 0;
for (unsigned i = 0, e = Args.size(); i != e; ++i)
switch (getValueType(Args[i].second)) {
default: assert(0 && "Unknown value type!");
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
if (NumIntRegs < FASTCC_NUM_INT_ARGS_INREGS) {
++NumIntRegs;
break;
}
// fall through
case MVT::f32:
NumBytes += 4;
break;
case MVT::i64:
if (NumIntRegs+2 <= FASTCC_NUM_INT_ARGS_INREGS) {
NumIntRegs += 2;
break;
} else if (NumIntRegs+1 <= FASTCC_NUM_INT_ARGS_INREGS) {
NumIntRegs = FASTCC_NUM_INT_ARGS_INREGS;
NumBytes += 4;
break;
}
// fall through
case MVT::f64:
NumBytes += 8;
break;
}
// Make sure the instruction takes 8n+4 bytes to make sure the start of the
// arguments and the arguments after the retaddr has been pushed are aligned.
if ((NumBytes & 7) == 0)
NumBytes += 4;
Chain = DAG.getCALLSEQ_START(Chain,DAG.getConstant(NumBytes, getPointerTy()));
// Arguments go on the stack in reverse order, as specified by the ABI.
unsigned ArgOffset = 0;
SDOperand StackPtr = DAG.getRegister(X86::ESP, MVT::i32);
NumIntRegs = 0;
std::vector<SDOperand> Stores;
std::vector<SDOperand> RegValuesToPass;
for (unsigned i = 0, e = Args.size(); i != e; ++i) {
switch (getValueType(Args[i].second)) {
default: assert(0 && "Unexpected ValueType for argument!");
case MVT::i1:
Args[i].first = DAG.getNode(ISD::ANY_EXTEND, MVT::i8, Args[i].first);
// Fall through.
case MVT::i8:
case MVT::i16:
case MVT::i32:
if (NumIntRegs < FASTCC_NUM_INT_ARGS_INREGS) {
RegValuesToPass.push_back(Args[i].first);
++NumIntRegs;
break;
}
// Fall through
case MVT::f32: {
SDOperand PtrOff = DAG.getConstant(ArgOffset, getPointerTy());
PtrOff = DAG.getNode(ISD::ADD, MVT::i32, StackPtr, PtrOff);
Stores.push_back(DAG.getNode(ISD::STORE, MVT::Other, Chain,
Args[i].first, PtrOff,
DAG.getSrcValue(NULL)));
ArgOffset += 4;
break;
}
case MVT::i64:
// Can pass (at least) part of it in regs?
if (NumIntRegs < FASTCC_NUM_INT_ARGS_INREGS) {
SDOperand Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, MVT::i32,
Args[i].first, DAG.getConstant(1, MVT::i32));
SDOperand Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, MVT::i32,
Args[i].first, DAG.getConstant(0, MVT::i32));
RegValuesToPass.push_back(Lo);
++NumIntRegs;
// Pass both parts in regs?
if (NumIntRegs < FASTCC_NUM_INT_ARGS_INREGS) {
RegValuesToPass.push_back(Hi);
++NumIntRegs;
} else {
// Pass the high part in memory.
SDOperand PtrOff = DAG.getConstant(ArgOffset, getPointerTy());
PtrOff = DAG.getNode(ISD::ADD, MVT::i32, StackPtr, PtrOff);
Stores.push_back(DAG.getNode(ISD::STORE, MVT::Other, Chain,
Hi, PtrOff, DAG.getSrcValue(NULL)));
ArgOffset += 4;
}
break;
}
// Fall through
case MVT::f64:
SDOperand PtrOff = DAG.getConstant(ArgOffset, getPointerTy());
PtrOff = DAG.getNode(ISD::ADD, MVT::i32, StackPtr, PtrOff);
Stores.push_back(DAG.getNode(ISD::STORE, MVT::Other, Chain,
Args[i].first, PtrOff,
DAG.getSrcValue(NULL)));
ArgOffset += 8;
break;
}
}
if (!Stores.empty())
Chain = DAG.getNode(ISD::TokenFactor, MVT::Other, Stores);
// Make sure the instruction takes 8n+4 bytes to make sure the start of the
// arguments and the arguments after the retaddr has been pushed are aligned.
if ((ArgOffset & 7) == 0)
ArgOffset += 4;
std::vector<MVT::ValueType> RetVals;
MVT::ValueType RetTyVT = getValueType(RetTy);
RetVals.push_back(MVT::Other);
// The result values produced have to be legal. Promote the result.
switch (RetTyVT) {
case MVT::isVoid: break;
default:
RetVals.push_back(RetTyVT);
break;
case MVT::i1:
case MVT::i8:
case MVT::i16:
RetVals.push_back(MVT::i32);
break;
case MVT::f32:
if (X86ScalarSSE)
RetVals.push_back(MVT::f32);
else
RetVals.push_back(MVT::f64);
break;
case MVT::i64:
RetVals.push_back(MVT::i32);
RetVals.push_back(MVT::i32);
break;
}
// Build a sequence of copy-to-reg nodes chained together with token chain
// and flag operands which copy the outgoing args into registers.
SDOperand InFlag;
for (unsigned i = 0, e = RegValuesToPass.size(); i != e; ++i) {
unsigned CCReg;
SDOperand RegToPass = RegValuesToPass[i];
switch (RegToPass.getValueType()) {
default: assert(0 && "Bad thing to pass in regs");
case MVT::i8:
CCReg = (i == 0) ? X86::AL : X86::DL;
break;
case MVT::i16:
CCReg = (i == 0) ? X86::AX : X86::DX;
break;
case MVT::i32:
CCReg = (i == 0) ? X86::EAX : X86::EDX;
break;
}
Chain = DAG.getCopyToReg(Chain, CCReg, RegToPass, InFlag);
InFlag = Chain.getValue(1);
}
std::vector<MVT::ValueType> NodeTys;
NodeTys.push_back(MVT::Other); // Returns a chain
NodeTys.push_back(MVT::Flag); // Returns a flag for retval copy to use.
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(Callee);
if (InFlag.Val)
Ops.push_back(InFlag);
// FIXME: Do not generate X86ISD::TAILCALL for now.
Chain = DAG.getNode(X86ISD::CALL, NodeTys, Ops);
InFlag = Chain.getValue(1);
NodeTys.clear();
NodeTys.push_back(MVT::Other); // Returns a chain
NodeTys.push_back(MVT::Flag); // Returns a flag for retval copy to use.
Ops.clear();
Ops.push_back(Chain);
Ops.push_back(DAG.getConstant(ArgOffset, getPointerTy()));
Ops.push_back(DAG.getConstant(ArgOffset, getPointerTy()));
Ops.push_back(InFlag);
Chain = DAG.getNode(ISD::CALLSEQ_END, NodeTys, Ops);
InFlag = Chain.getValue(1);
SDOperand RetVal;
if (RetTyVT != MVT::isVoid) {
switch (RetTyVT) {
default: assert(0 && "Unknown value type to return!");
case MVT::i1:
case MVT::i8:
RetVal = DAG.getCopyFromReg(Chain, X86::AL, MVT::i8, InFlag);
Chain = RetVal.getValue(1);
if (RetTyVT == MVT::i1)
RetVal = DAG.getNode(ISD::TRUNCATE, MVT::i1, RetVal);
break;
case MVT::i16:
RetVal = DAG.getCopyFromReg(Chain, X86::AX, MVT::i16, InFlag);
Chain = RetVal.getValue(1);
break;
case MVT::i32:
RetVal = DAG.getCopyFromReg(Chain, X86::EAX, MVT::i32, InFlag);
Chain = RetVal.getValue(1);
break;
case MVT::i64: {
SDOperand Lo = DAG.getCopyFromReg(Chain, X86::EAX, MVT::i32, InFlag);
SDOperand Hi = DAG.getCopyFromReg(Lo.getValue(1), X86::EDX, MVT::i32,
Lo.getValue(2));
RetVal = DAG.getNode(ISD::BUILD_PAIR, MVT::i64, Lo, Hi);
Chain = Hi.getValue(1);
break;
}
case MVT::f32:
case MVT::f64: {
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::f64);
Tys.push_back(MVT::Other);
Tys.push_back(MVT::Flag);
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(InFlag);
RetVal = DAG.getNode(X86ISD::FP_GET_RESULT, Tys, Ops);
Chain = RetVal.getValue(1);
InFlag = RetVal.getValue(2);
if (X86ScalarSSE) {
// FIXME: Currently the FST is flagged to the FP_GET_RESULT. This
// shouldn't be necessary except that RFP cannot be live across
// multiple blocks. When stackifier is fixed, they can be uncoupled.
MachineFunction &MF = DAG.getMachineFunction();
int SSFI = MF.getFrameInfo()->CreateStackObject(8, 8);
SDOperand StackSlot = DAG.getFrameIndex(SSFI, getPointerTy());
Tys.clear();
Tys.push_back(MVT::Other);
Ops.clear();
Ops.push_back(Chain);
Ops.push_back(RetVal);
Ops.push_back(StackSlot);
Ops.push_back(DAG.getValueType(RetTyVT));
Ops.push_back(InFlag);
Chain = DAG.getNode(X86ISD::FST, Tys, Ops);
RetVal = DAG.getLoad(RetTyVT, Chain, StackSlot,
DAG.getSrcValue(NULL));
Chain = RetVal.getValue(1);
}
if (RetTyVT == MVT::f32 && !X86ScalarSSE)
// FIXME: we would really like to remember that this FP_ROUND
// operation is okay to eliminate if we allow excess FP precision.
RetVal = DAG.getNode(ISD::FP_ROUND, MVT::f32, RetVal);
break;
}
}
}
return std::make_pair(RetVal, Chain);
}
SDOperand X86TargetLowering::getReturnAddressFrameIndex(SelectionDAG &DAG) {
if (ReturnAddrIndex == 0) {
// Set up a frame object for the return address.
MachineFunction &MF = DAG.getMachineFunction();
ReturnAddrIndex = MF.getFrameInfo()->CreateFixedObject(4, -4);
}
return DAG.getFrameIndex(ReturnAddrIndex, MVT::i32);
}
std::pair<SDOperand, SDOperand> X86TargetLowering::
LowerFrameReturnAddress(bool isFrameAddress, SDOperand Chain, unsigned Depth,
SelectionDAG &DAG) {
SDOperand Result;
if (Depth) // Depths > 0 not supported yet!
Result = DAG.getConstant(0, getPointerTy());
else {
SDOperand RetAddrFI = getReturnAddressFrameIndex(DAG);
if (!isFrameAddress)
// Just load the return address
Result = DAG.getLoad(MVT::i32, DAG.getEntryNode(), RetAddrFI,
DAG.getSrcValue(NULL));
else
Result = DAG.getNode(ISD::SUB, MVT::i32, RetAddrFI,
DAG.getConstant(4, MVT::i32));
}
return std::make_pair(Result, Chain);
}
/// getCondBrOpcodeForX86CC - Returns the X86 conditional branch opcode
/// which corresponds to the condition code.
static unsigned getCondBrOpcodeForX86CC(unsigned X86CC) {
switch (X86CC) {
default: assert(0 && "Unknown X86 conditional code!");
case X86ISD::COND_A: return X86::JA;
case X86ISD::COND_AE: return X86::JAE;
case X86ISD::COND_B: return X86::JB;
case X86ISD::COND_BE: return X86::JBE;
case X86ISD::COND_E: return X86::JE;
case X86ISD::COND_G: return X86::JG;
case X86ISD::COND_GE: return X86::JGE;
case X86ISD::COND_L: return X86::JL;
case X86ISD::COND_LE: return X86::JLE;
case X86ISD::COND_NE: return X86::JNE;
case X86ISD::COND_NO: return X86::JNO;
case X86ISD::COND_NP: return X86::JNP;
case X86ISD::COND_NS: return X86::JNS;
case X86ISD::COND_O: return X86::JO;
case X86ISD::COND_P: return X86::JP;
case X86ISD::COND_S: return X86::JS;
}
}
/// translateX86CC - do a one to one translation of a ISD::CondCode to the X86
/// specific condition code. It returns a false if it cannot do a direct
/// translation. X86CC is the translated CondCode. Flip is set to true if the
/// the order of comparison operands should be flipped.
static bool translateX86CC(SDOperand CC, bool isFP, unsigned &X86CC,
bool &Flip) {
ISD::CondCode SetCCOpcode = cast<CondCodeSDNode>(CC)->get();
Flip = false;
X86CC = X86ISD::COND_INVALID;
if (!isFP) {
switch (SetCCOpcode) {
default: break;
case ISD::SETEQ: X86CC = X86ISD::COND_E; break;
case ISD::SETGT: X86CC = X86ISD::COND_G; break;
case ISD::SETGE: X86CC = X86ISD::COND_GE; break;
case ISD::SETLT: X86CC = X86ISD::COND_L; break;
case ISD::SETLE: X86CC = X86ISD::COND_LE; break;
case ISD::SETNE: X86CC = X86ISD::COND_NE; break;
case ISD::SETULT: X86CC = X86ISD::COND_B; break;
case ISD::SETUGT: X86CC = X86ISD::COND_A; break;
case ISD::SETULE: X86CC = X86ISD::COND_BE; break;
case ISD::SETUGE: X86CC = X86ISD::COND_AE; break;
}
} else {
// On a floating point condition, the flags are set as follows:
// ZF PF CF op
// 0 | 0 | 0 | X > Y
// 0 | 0 | 1 | X < Y
// 1 | 0 | 0 | X == Y
// 1 | 1 | 1 | unordered
switch (SetCCOpcode) {
default: break;
case ISD::SETUEQ:
case ISD::SETEQ: X86CC = X86ISD::COND_E; break;
case ISD::SETOLE: Flip = true; // Fallthrough
case ISD::SETOGT:
case ISD::SETGT: X86CC = X86ISD::COND_A; break;
case ISD::SETOLT: Flip = true; // Fallthrough
case ISD::SETOGE:
case ISD::SETGE: X86CC = X86ISD::COND_AE; break;
case ISD::SETUGE: Flip = true; // Fallthrough
case ISD::SETULT:
case ISD::SETLT: X86CC = X86ISD::COND_B; break;
case ISD::SETUGT: Flip = true; // Fallthrough
case ISD::SETULE:
case ISD::SETLE: X86CC = X86ISD::COND_BE; break;
case ISD::SETONE:
case ISD::SETNE: X86CC = X86ISD::COND_NE; break;
case ISD::SETUO: X86CC = X86ISD::COND_P; break;
case ISD::SETO: X86CC = X86ISD::COND_NP; break;
}
}
return X86CC != X86ISD::COND_INVALID;
}
/// hasFPCMov - is there a floating point cmov for the specific X86 condition
/// code. Current x86 isa includes the following FP cmov instructions:
/// fcmovb, fcomvbe, fcomve, fcmovu, fcmovae, fcmova, fcmovne, fcmovnu.
static bool hasFPCMov(unsigned X86CC) {
switch (X86CC) {
default:
return false;
case X86ISD::COND_B:
case X86ISD::COND_BE:
case X86ISD::COND_E:
case X86ISD::COND_P:
case X86ISD::COND_A:
case X86ISD::COND_AE:
case X86ISD::COND_NE:
case X86ISD::COND_NP:
return true;
}
}
MachineBasicBlock *
X86TargetLowering::InsertAtEndOfBasicBlock(MachineInstr *MI,
MachineBasicBlock *BB) {
switch (MI->getOpcode()) {
default: assert(false && "Unexpected instr type to insert");
case X86::CMOV_FR32:
case X86::CMOV_FR64: {
// 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();
ilist<MachineBasicBlock>::iterator It = BB;
++It;
// thisMBB:
// ...
// TrueVal = ...
// cmpTY ccX, r1, r2
// bCC copy1MBB
// fallthrough --> copy0MBB
MachineBasicBlock *thisMBB = BB;
MachineBasicBlock *copy0MBB = new MachineBasicBlock(LLVM_BB);
MachineBasicBlock *sinkMBB = new MachineBasicBlock(LLVM_BB);
unsigned Opc = getCondBrOpcodeForX86CC(MI->getOperand(3).getImmedValue());
BuildMI(BB, Opc, 1).addMBB(sinkMBB);
MachineFunction *F = BB->getParent();
F->getBasicBlockList().insert(It, copy0MBB);
F->getBasicBlockList().insert(It, sinkMBB);
// Update machine-CFG edges
BB->addSuccessor(copy0MBB);
BB->addSuccessor(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, X86::PHI, 4, MI->getOperand(0).getReg())
.addReg(MI->getOperand(1).getReg()).addMBB(copy0MBB)
.addReg(MI->getOperand(2).getReg()).addMBB(thisMBB);
delete MI; // The pseudo instruction is gone now.
return BB;
}
case X86::FP_TO_INT16_IN_MEM:
case X86::FP_TO_INT32_IN_MEM:
case X86::FP_TO_INT64_IN_MEM: {
// Change the floating point control register to use "round towards zero"
// mode when truncating to an integer value.
MachineFunction *F = BB->getParent();
int CWFrameIdx = F->getFrameInfo()->CreateStackObject(2, 2);
addFrameReference(BuildMI(BB, X86::FNSTCW16m, 4), CWFrameIdx);
// Load the old value of the high byte of the control word...
unsigned OldCW =
F->getSSARegMap()->createVirtualRegister(X86::R16RegisterClass);
addFrameReference(BuildMI(BB, X86::MOV16rm, 4, OldCW), CWFrameIdx);
// Set the high part to be round to zero...
addFrameReference(BuildMI(BB, X86::MOV16mi, 5), CWFrameIdx).addImm(0xC7F);
// Reload the modified control word now...
addFrameReference(BuildMI(BB, X86::FLDCW16m, 4), CWFrameIdx);
// Restore the memory image of control word to original value
addFrameReference(BuildMI(BB, X86::MOV16mr, 5), CWFrameIdx).addReg(OldCW);
// Get the X86 opcode to use.
unsigned Opc;
switch (MI->getOpcode()) {
default: assert(0 && "illegal opcode!");
case X86::FP_TO_INT16_IN_MEM: Opc = X86::FpIST16m; break;
case X86::FP_TO_INT32_IN_MEM: Opc = X86::FpIST32m; break;
case X86::FP_TO_INT64_IN_MEM: Opc = X86::FpIST64m; break;
}
X86AddressMode AM;
MachineOperand &Op = MI->getOperand(0);
if (Op.isRegister()) {
AM.BaseType = X86AddressMode::RegBase;
AM.Base.Reg = Op.getReg();
} else {
AM.BaseType = X86AddressMode::FrameIndexBase;
AM.Base.FrameIndex = Op.getFrameIndex();
}
Op = MI->getOperand(1);
if (Op.isImmediate())
AM.Scale = Op.getImmedValue();
Op = MI->getOperand(2);
if (Op.isImmediate())
AM.IndexReg = Op.getImmedValue();
Op = MI->getOperand(3);
if (Op.isGlobalAddress()) {
AM.GV = Op.getGlobal();
} else {
AM.Disp = Op.getImmedValue();
}
addFullAddress(BuildMI(BB, Opc, 5), AM).addReg(MI->getOperand(4).getReg());
// Reload the original control word now.
addFrameReference(BuildMI(BB, X86::FLDCW16m, 4), CWFrameIdx);
delete MI; // The pseudo instruction is gone now.
return BB;
}
}
}
//===----------------------------------------------------------------------===//
// X86 Custom Lowering Hooks
//===----------------------------------------------------------------------===//
/// DarwinGVRequiresExtraLoad - true if accessing the GV requires an extra
/// load. For Darwin, external and weak symbols are indirect, loading the value
/// at address GV rather then the value of GV itself. This means that the
/// GlobalAddress must be in the base or index register of the address, not the
/// GV offset field.
static bool DarwinGVRequiresExtraLoad(GlobalValue *GV) {
return (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
(GV->isExternal() && !GV->hasNotBeenReadFromBytecode()));
}
/// LowerOperation - Provide custom lowering hooks for some operations.
///
SDOperand X86TargetLowering::LowerOperation(SDOperand Op, SelectionDAG &DAG) {
switch (Op.getOpcode()) {
default: assert(0 && "Should not custom lower this!");
case ISD::SHL_PARTS:
case ISD::SRA_PARTS:
case ISD::SRL_PARTS: {
assert(Op.getNumOperands() == 3 && Op.getValueType() == MVT::i32 &&
"Not an i64 shift!");
bool isSRA = Op.getOpcode() == ISD::SRA_PARTS;
SDOperand ShOpLo = Op.getOperand(0);
SDOperand ShOpHi = Op.getOperand(1);
SDOperand ShAmt = Op.getOperand(2);
SDOperand Tmp1 = isSRA ? DAG.getNode(ISD::SRA, MVT::i32, ShOpHi,
DAG.getConstant(31, MVT::i8))
: DAG.getConstant(0, MVT::i32);
SDOperand Tmp2, Tmp3;
if (Op.getOpcode() == ISD::SHL_PARTS) {
Tmp2 = DAG.getNode(X86ISD::SHLD, MVT::i32, ShOpHi, ShOpLo, ShAmt);
Tmp3 = DAG.getNode(ISD::SHL, MVT::i32, ShOpLo, ShAmt);
} else {
Tmp2 = DAG.getNode(X86ISD::SHRD, MVT::i32, ShOpLo, ShOpHi, ShAmt);
Tmp3 = DAG.getNode(isSRA ? ISD::SRA : ISD::SRL, MVT::i32, ShOpHi, ShAmt);
}
SDOperand InFlag = DAG.getNode(X86ISD::TEST, MVT::Flag,
ShAmt, DAG.getConstant(32, MVT::i8));
SDOperand Hi, Lo;
SDOperand CC = DAG.getConstant(X86ISD::COND_NE, MVT::i8);
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::i32);
Tys.push_back(MVT::Flag);
std::vector<SDOperand> Ops;
if (Op.getOpcode() == ISD::SHL_PARTS) {
Ops.push_back(Tmp2);
Ops.push_back(Tmp3);
Ops.push_back(CC);
Ops.push_back(InFlag);
Hi = DAG.getNode(X86ISD::CMOV, Tys, Ops);
InFlag = Hi.getValue(1);
Ops.clear();
Ops.push_back(Tmp3);
Ops.push_back(Tmp1);
Ops.push_back(CC);
Ops.push_back(InFlag);
Lo = DAG.getNode(X86ISD::CMOV, Tys, Ops);
} else {
Ops.push_back(Tmp2);
Ops.push_back(Tmp3);
Ops.push_back(CC);
Ops.push_back(InFlag);
Lo = DAG.getNode(X86ISD::CMOV, Tys, Ops);
InFlag = Lo.getValue(1);
Ops.clear();
Ops.push_back(Tmp3);
Ops.push_back(Tmp1);
Ops.push_back(CC);
Ops.push_back(InFlag);
Hi = DAG.getNode(X86ISD::CMOV, Tys, Ops);
}
Tys.clear();
Tys.push_back(MVT::i32);
Tys.push_back(MVT::i32);
Ops.clear();
Ops.push_back(Lo);
Ops.push_back(Hi);
return DAG.getNode(ISD::MERGE_VALUES, Tys, Ops);
}
case ISD::SINT_TO_FP: {
assert(Op.getOperand(0).getValueType() <= MVT::i64 &&
Op.getOperand(0).getValueType() >= MVT::i16 &&
"Unknown SINT_TO_FP to lower!");
SDOperand Result;
MVT::ValueType SrcVT = Op.getOperand(0).getValueType();
unsigned Size = MVT::getSizeInBits(SrcVT)/8;
MachineFunction &MF = DAG.getMachineFunction();
int SSFI = MF.getFrameInfo()->CreateStackObject(Size, Size);
SDOperand StackSlot = DAG.getFrameIndex(SSFI, getPointerTy());
SDOperand Chain = DAG.getNode(ISD::STORE, MVT::Other,
DAG.getEntryNode(), Op.getOperand(0),
StackSlot, DAG.getSrcValue(NULL));
// Build the FILD
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::f64);
Tys.push_back(MVT::Other);
if (X86ScalarSSE) Tys.push_back(MVT::Flag);
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(StackSlot);
Ops.push_back(DAG.getValueType(SrcVT));
Result = DAG.getNode(X86ScalarSSE ? X86ISD::FILD_FLAG :X86ISD::FILD,
Tys, Ops);
if (X86ScalarSSE) {
Chain = Result.getValue(1);
SDOperand InFlag = Result.getValue(2);
// FIXME: Currently the FST is flagged to the FILD_FLAG. This
// shouldn't be necessary except that RFP cannot be live across
// multiple blocks. When stackifier is fixed, they can be uncoupled.
MachineFunction &MF = DAG.getMachineFunction();
int SSFI = MF.getFrameInfo()->CreateStackObject(8, 8);
SDOperand StackSlot = DAG.getFrameIndex(SSFI, getPointerTy());
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::Other);
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(Result);
Ops.push_back(StackSlot);
Ops.push_back(DAG.getValueType(Op.getValueType()));
Ops.push_back(InFlag);
Chain = DAG.getNode(X86ISD::FST, Tys, Ops);
Result = DAG.getLoad(Op.getValueType(), Chain, StackSlot,
DAG.getSrcValue(NULL));
}
return Result;
}
case ISD::FP_TO_SINT: {
assert(Op.getValueType() <= MVT::i64 && Op.getValueType() >= MVT::i16 &&
"Unknown FP_TO_SINT to lower!");
// We lower FP->sint64 into FISTP64, followed by a load, all to a temporary
// stack slot.
MachineFunction &MF = DAG.getMachineFunction();
unsigned MemSize = MVT::getSizeInBits(Op.getValueType())/8;
int SSFI = MF.getFrameInfo()->CreateStackObject(MemSize, MemSize);
SDOperand StackSlot = DAG.getFrameIndex(SSFI, getPointerTy());
unsigned Opc;
switch (Op.getValueType()) {
default: assert(0 && "Invalid FP_TO_SINT to lower!");
case MVT::i16: Opc = X86ISD::FP_TO_INT16_IN_MEM; break;
case MVT::i32: Opc = X86ISD::FP_TO_INT32_IN_MEM; break;
case MVT::i64: Opc = X86ISD::FP_TO_INT64_IN_MEM; break;
}
SDOperand Chain = DAG.getEntryNode();
SDOperand Value = Op.getOperand(0);
if (X86ScalarSSE) {
assert(Op.getValueType() == MVT::i64 && "Invalid FP_TO_SINT to lower!");
Chain = DAG.getNode(ISD::STORE, MVT::Other, Chain, Value, StackSlot,
DAG.getSrcValue(0));
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::f64);
Tys.push_back(MVT::Other);
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(StackSlot);
Ops.push_back(DAG.getValueType(Op.getOperand(0).getValueType()));
Value = DAG.getNode(X86ISD::FLD, Tys, Ops);
Chain = Value.getValue(1);
SSFI = MF.getFrameInfo()->CreateStackObject(MemSize, MemSize);
StackSlot = DAG.getFrameIndex(SSFI, getPointerTy());
}
// Build the FP_TO_INT*_IN_MEM
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(Value);
Ops.push_back(StackSlot);
SDOperand FIST = DAG.getNode(Opc, MVT::Other, Ops);
// Load the result.
return DAG.getLoad(Op.getValueType(), FIST, StackSlot,
DAG.getSrcValue(NULL));
}
case ISD::READCYCLECOUNTER: {
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::Other);
Tys.push_back(MVT::Flag);
std::vector<SDOperand> Ops;
Ops.push_back(Op.getOperand(0));
SDOperand rd = DAG.getNode(X86ISD::RDTSC_DAG, Tys, Ops);
Ops.clear();
Ops.push_back(DAG.getCopyFromReg(rd, X86::EAX, MVT::i32, rd.getValue(1)));
Ops.push_back(DAG.getCopyFromReg(Ops[0].getValue(1), X86::EDX,
MVT::i32, Ops[0].getValue(2)));
Ops.push_back(Ops[1].getValue(1));
Tys[0] = Tys[1] = MVT::i32;
Tys.push_back(MVT::Other);
return DAG.getNode(ISD::MERGE_VALUES, Tys, Ops);
}
case ISD::FABS: {
MVT::ValueType VT = Op.getValueType();
const Type *OpNTy = MVT::getTypeForValueType(VT);
std::vector<Constant*> CV;
if (VT == MVT::f64) {
CV.push_back(ConstantFP::get(OpNTy, BitsToDouble(~(1ULL << 63))));
CV.push_back(ConstantFP::get(OpNTy, 0.0));
} else {
CV.push_back(ConstantFP::get(OpNTy, BitsToFloat(~(1U << 31))));
CV.push_back(ConstantFP::get(OpNTy, 0.0));
CV.push_back(ConstantFP::get(OpNTy, 0.0));
CV.push_back(ConstantFP::get(OpNTy, 0.0));
}
Constant *CS = ConstantStruct::get(CV);
SDOperand CPIdx = DAG.getConstantPool(CS, getPointerTy(), 4);
SDOperand Mask
= DAG.getNode(X86ISD::LOAD_PACK,
VT, DAG.getEntryNode(), CPIdx, DAG.getSrcValue(NULL));
return DAG.getNode(X86ISD::FAND, VT, Op.getOperand(0), Mask);
}
case ISD::FNEG: {
MVT::ValueType VT = Op.getValueType();
const Type *OpNTy = MVT::getTypeForValueType(VT);
std::vector<Constant*> CV;
if (VT == MVT::f64) {
CV.push_back(ConstantFP::get(OpNTy, BitsToDouble(1ULL << 63)));
CV.push_back(ConstantFP::get(OpNTy, 0.0));
} else {
CV.push_back(ConstantFP::get(OpNTy, BitsToFloat(1U << 31)));
CV.push_back(ConstantFP::get(OpNTy, 0.0));
CV.push_back(ConstantFP::get(OpNTy, 0.0));
CV.push_back(ConstantFP::get(OpNTy, 0.0));
}
Constant *CS = ConstantStruct::get(CV);
SDOperand CPIdx = DAG.getConstantPool(CS, getPointerTy(), 4);
SDOperand Mask
= DAG.getNode(X86ISD::LOAD_PACK,
VT, DAG.getEntryNode(), CPIdx, DAG.getSrcValue(NULL));
return DAG.getNode(X86ISD::FXOR, VT, Op.getOperand(0), Mask);
}
case ISD::SETCC: {
assert(Op.getValueType() == MVT::i8 && "SetCC type must be 8-bit integer");
SDOperand Cond;
SDOperand CC = Op.getOperand(2);
ISD::CondCode SetCCOpcode = cast<CondCodeSDNode>(CC)->get();
bool isFP = MVT::isFloatingPoint(Op.getOperand(1).getValueType());
bool Flip;
unsigned X86CC;
if (translateX86CC(CC, isFP, X86CC, Flip)) {
if (Flip)
Cond = DAG.getNode(X86ISD::CMP, MVT::Flag,
Op.getOperand(1), Op.getOperand(0));
else
Cond = DAG.getNode(X86ISD::CMP, MVT::Flag,
Op.getOperand(0), Op.getOperand(1));
return DAG.getNode(X86ISD::SETCC, MVT::i8,
DAG.getConstant(X86CC, MVT::i8), Cond);
} else {
assert(isFP && "Illegal integer SetCC!");
Cond = DAG.getNode(X86ISD::CMP, MVT::Flag,
Op.getOperand(0), Op.getOperand(1));
std::vector<MVT::ValueType> Tys;
std::vector<SDOperand> Ops;
switch (SetCCOpcode) {
default: assert(false && "Illegal floating point SetCC!");
case ISD::SETOEQ: { // !PF & ZF
Tys.push_back(MVT::i8);
Tys.push_back(MVT::Flag);
Ops.push_back(DAG.getConstant(X86ISD::COND_NP, MVT::i8));
Ops.push_back(Cond);
SDOperand Tmp1 = DAG.getNode(X86ISD::SETCC, Tys, Ops);
SDOperand Tmp2 = DAG.getNode(X86ISD::SETCC, MVT::i8,
DAG.getConstant(X86ISD::COND_E, MVT::i8),
Tmp1.getValue(1));
return DAG.getNode(ISD::AND, MVT::i8, Tmp1, Tmp2);
}
case ISD::SETUNE: { // PF | !ZF
Tys.push_back(MVT::i8);
Tys.push_back(MVT::Flag);
Ops.push_back(DAG.getConstant(X86ISD::COND_P, MVT::i8));
Ops.push_back(Cond);
SDOperand Tmp1 = DAG.getNode(X86ISD::SETCC, Tys, Ops);
SDOperand Tmp2 = DAG.getNode(X86ISD::SETCC, MVT::i8,
DAG.getConstant(X86ISD::COND_NE, MVT::i8),
Tmp1.getValue(1));
return DAG.getNode(ISD::OR, MVT::i8, Tmp1, Tmp2);
}
}
}
}
case ISD::SELECT: {
MVT::ValueType VT = Op.getValueType();
bool isFP = MVT::isFloatingPoint(VT);
bool isFPStack = isFP && !X86ScalarSSE;
bool isFPSSE = isFP && X86ScalarSSE;
bool addTest = false;
SDOperand Op0 = Op.getOperand(0);
SDOperand Cond, CC;
if (Op0.getOpcode() == ISD::SETCC)
Op0 = LowerOperation(Op0, DAG);
if (Op0.getOpcode() == X86ISD::SETCC) {
// If condition flag is set by a X86ISD::CMP, then make a copy of it
// (since flag operand cannot be shared). If the X86ISD::SETCC does not
// have another use it will be eliminated.
// If the X86ISD::SETCC has more than one use, then it's probably better
// to use a test instead of duplicating the X86ISD::CMP (for register
// pressure reason).
if (Op0.getOperand(1).getOpcode() == X86ISD::CMP) {
if (!Op0.hasOneUse()) {
std::vector<MVT::ValueType> Tys;
for (unsigned i = 0; i < Op0.Val->getNumValues(); ++i)
Tys.push_back(Op0.Val->getValueType(i));
std::vector<SDOperand> Ops;
for (unsigned i = 0; i < Op0.getNumOperands(); ++i)
Ops.push_back(Op0.getOperand(i));
Op0 = DAG.getNode(X86ISD::SETCC, Tys, Ops);
}
CC = Op0.getOperand(0);
Cond = Op0.getOperand(1);
// Make a copy as flag result cannot be used by more than one.
Cond = DAG.getNode(X86ISD::CMP, MVT::Flag,
Cond.getOperand(0), Cond.getOperand(1));
addTest =
isFPStack && !hasFPCMov(cast<ConstantSDNode>(CC)->getSignExtended());
} else
addTest = true;
} else
addTest = true;
if (addTest) {
CC = DAG.getConstant(X86ISD::COND_NE, MVT::i8);
Cond = DAG.getNode(X86ISD::TEST, MVT::Flag, Op0, Op0);
}
std::vector<MVT::ValueType> Tys;
Tys.push_back(Op.getValueType());
Tys.push_back(MVT::Flag);
std::vector<SDOperand> Ops;
// X86ISD::CMOV means set the result (which is operand 1) to the RHS if
// condition is true.
Ops.push_back(Op.getOperand(2));
Ops.push_back(Op.getOperand(1));
Ops.push_back(CC);
Ops.push_back(Cond);
return DAG.getNode(X86ISD::CMOV, Tys, Ops);
}
case ISD::BRCOND: {
bool addTest = false;
SDOperand Cond = Op.getOperand(1);
SDOperand Dest = Op.getOperand(2);
SDOperand CC;
if (Cond.getOpcode() == ISD::SETCC)
Cond = LowerOperation(Cond, DAG);
if (Cond.getOpcode() == X86ISD::SETCC) {
// If condition flag is set by a X86ISD::CMP, then make a copy of it
// (since flag operand cannot be shared). If the X86ISD::SETCC does not
// have another use it will be eliminated.
// If the X86ISD::SETCC has more than one use, then it's probably better
// to use a test instead of duplicating the X86ISD::CMP (for register
// pressure reason).
if (Cond.getOperand(1).getOpcode() == X86ISD::CMP) {
if (!Cond.hasOneUse()) {
std::vector<MVT::ValueType> Tys;
for (unsigned i = 0; i < Cond.Val->getNumValues(); ++i)
Tys.push_back(Cond.Val->getValueType(i));
std::vector<SDOperand> Ops;
for (unsigned i = 0; i < Cond.getNumOperands(); ++i)
Ops.push_back(Cond.getOperand(i));
Cond = DAG.getNode(X86ISD::SETCC, Tys, Ops);
}
CC = Cond.getOperand(0);
Cond = Cond.getOperand(1);
// Make a copy as flag result cannot be used by more than one.
Cond = DAG.getNode(X86ISD::CMP, MVT::Flag,
Cond.getOperand(0), Cond.getOperand(1));
} else
addTest = true;
} else
addTest = true;
if (addTest) {
CC = DAG.getConstant(X86ISD::COND_NE, MVT::i8);
Cond = DAG.getNode(X86ISD::TEST, MVT::Flag, Cond, Cond);
}
return DAG.getNode(X86ISD::BRCOND, Op.getValueType(),
Op.getOperand(0), Op.getOperand(2), CC, Cond);
}
case ISD::MEMSET: {
SDOperand InFlag(0, 0);
SDOperand Chain = Op.getOperand(0);
unsigned Align =
(unsigned)cast<ConstantSDNode>(Op.getOperand(4))->getValue();
if (Align == 0) Align = 1;
ConstantSDNode *I = dyn_cast<ConstantSDNode>(Op.getOperand(3));
// If not DWORD aligned, call memset if size is less than the threshold.
// It knows how to align to the right boundary first.
if ((Align & 3) != 0 ||
(I && I->getValue() < Subtarget->getMinRepStrSizeThreshold())) {
MVT::ValueType IntPtr = getPointerTy();
const Type *IntPtrTy = getTargetData().getIntPtrType();
std::vector<std::pair<SDOperand, const Type*> > Args;
Args.push_back(std::make_pair(Op.getOperand(1), IntPtrTy));
// Extend the ubyte argument to be an int value for the call.
SDOperand Val = DAG.getNode(ISD::ZERO_EXTEND, MVT::i32, Op.getOperand(2));
Args.push_back(std::make_pair(Val, IntPtrTy));
Args.push_back(std::make_pair(Op.getOperand(3), IntPtrTy));
std::pair<SDOperand,SDOperand> CallResult =
LowerCallTo(Chain, Type::VoidTy, false, CallingConv::C, false,
DAG.getExternalSymbol("memset", IntPtr), Args, DAG);
return CallResult.second;
}
MVT::ValueType AVT;
SDOperand Count;
ConstantSDNode *ValC = dyn_cast<ConstantSDNode>(Op.getOperand(2));
unsigned BytesLeft = 0;
bool TwoRepStos = false;
if (ValC) {
unsigned ValReg;
unsigned Val = ValC->getValue() & 255;
// If the value is a constant, then we can potentially use larger sets.
switch (Align & 3) {
case 2: // WORD aligned
AVT = MVT::i16;
Count = DAG.getConstant(I->getValue() / 2, MVT::i32);
BytesLeft = I->getValue() % 2;
Val = (Val << 8) | Val;
ValReg = X86::AX;
break;
case 0: // DWORD aligned
AVT = MVT::i32;
if (I) {
Count = DAG.getConstant(I->getValue() / 4, MVT::i32);
BytesLeft = I->getValue() % 4;
} else {
Count = DAG.getNode(ISD::SRL, MVT::i32, Op.getOperand(3),
DAG.getConstant(2, MVT::i8));
TwoRepStos = true;
}
Val = (Val << 8) | Val;
Val = (Val << 16) | Val;
ValReg = X86::EAX;
break;
default: // Byte aligned
AVT = MVT::i8;
Count = Op.getOperand(3);
ValReg = X86::AL;
break;
}
Chain = DAG.getCopyToReg(Chain, ValReg, DAG.getConstant(Val, AVT),
InFlag);
InFlag = Chain.getValue(1);
} else {
AVT = MVT::i8;
Count = Op.getOperand(3);
Chain = DAG.getCopyToReg(Chain, X86::AL, Op.getOperand(2), InFlag);
InFlag = Chain.getValue(1);
}
Chain = DAG.getCopyToReg(Chain, X86::ECX, Count, InFlag);
InFlag = Chain.getValue(1);
Chain = DAG.getCopyToReg(Chain, X86::EDI, Op.getOperand(1), InFlag);
InFlag = Chain.getValue(1);
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::Other);
Tys.push_back(MVT::Flag);
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(DAG.getValueType(AVT));
Ops.push_back(InFlag);
Chain = DAG.getNode(X86ISD::REP_STOS, Tys, Ops);
if (TwoRepStos) {
InFlag = Chain.getValue(1);
Count = Op.getOperand(3);
MVT::ValueType CVT = Count.getValueType();
SDOperand Left = DAG.getNode(ISD::AND, CVT, Count,
DAG.getConstant(3, CVT));
Chain = DAG.getCopyToReg(Chain, X86::ECX, Left, InFlag);
InFlag = Chain.getValue(1);
Tys.clear();
Tys.push_back(MVT::Other);
Tys.push_back(MVT::Flag);
Ops.clear();
Ops.push_back(Chain);
Ops.push_back(DAG.getValueType(MVT::i8));
Ops.push_back(InFlag);
Chain = DAG.getNode(X86ISD::REP_STOS, Tys, Ops);
} else if (BytesLeft) {
// Issue stores for the last 1 - 3 bytes.
SDOperand Value;
unsigned Val = ValC->getValue() & 255;
unsigned Offset = I->getValue() - BytesLeft;
SDOperand DstAddr = Op.getOperand(1);
MVT::ValueType AddrVT = DstAddr.getValueType();
if (BytesLeft >= 2) {
Value = DAG.getConstant((Val << 8) | Val, MVT::i16);
Chain = DAG.getNode(ISD::STORE, MVT::Other, Chain, Value,
DAG.getNode(ISD::ADD, AddrVT, DstAddr,
DAG.getConstant(Offset, AddrVT)),
DAG.getSrcValue(NULL));
BytesLeft -= 2;
Offset += 2;
}
if (BytesLeft == 1) {
Value = DAG.getConstant(Val, MVT::i8);
Chain = DAG.getNode(ISD::STORE, MVT::Other, Chain, Value,
DAG.getNode(ISD::ADD, AddrVT, DstAddr,
DAG.getConstant(Offset, AddrVT)),
DAG.getSrcValue(NULL));
}
}
return Chain;
}
case ISD::MEMCPY: {
SDOperand Chain = Op.getOperand(0);
unsigned Align =
(unsigned)cast<ConstantSDNode>(Op.getOperand(4))->getValue();
if (Align == 0) Align = 1;
ConstantSDNode *I = dyn_cast<ConstantSDNode>(Op.getOperand(3));
// If not DWORD aligned, call memcpy if size is less than the threshold.
// It knows how to align to the right boundary first.
if ((Align & 3) != 0 ||
(I && I->getValue() < Subtarget->getMinRepStrSizeThreshold())) {
MVT::ValueType IntPtr = getPointerTy();
const Type *IntPtrTy = getTargetData().getIntPtrType();
std::vector<std::pair<SDOperand, const Type*> > Args;
Args.push_back(std::make_pair(Op.getOperand(1), IntPtrTy));
Args.push_back(std::make_pair(Op.getOperand(2), IntPtrTy));
Args.push_back(std::make_pair(Op.getOperand(3), IntPtrTy));
std::pair<SDOperand,SDOperand> CallResult =
LowerCallTo(Chain, Type::VoidTy, false, CallingConv::C, false,
DAG.getExternalSymbol("memcpy", IntPtr), Args, DAG);
return CallResult.second;
}
MVT::ValueType AVT;
SDOperand Count;
unsigned BytesLeft = 0;
bool TwoRepMovs = false;
switch (Align & 3) {
case 2: // WORD aligned
AVT = MVT::i16;
Count = DAG.getConstant(I->getValue() / 2, MVT::i32);
BytesLeft = I->getValue() % 2;
break;
case 0: // DWORD aligned
AVT = MVT::i32;
if (I) {
Count = DAG.getConstant(I->getValue() / 4, MVT::i32);
BytesLeft = I->getValue() % 4;
} else {
Count = DAG.getNode(ISD::SRL, MVT::i32, Op.getOperand(3),
DAG.getConstant(2, MVT::i8));
TwoRepMovs = true;
}
break;
default: // Byte aligned
AVT = MVT::i8;
Count = Op.getOperand(3);
break;
}
SDOperand InFlag(0, 0);
Chain = DAG.getCopyToReg(Chain, X86::ECX, Count, InFlag);
InFlag = Chain.getValue(1);
Chain = DAG.getCopyToReg(Chain, X86::EDI, Op.getOperand(1), InFlag);
InFlag = Chain.getValue(1);
Chain = DAG.getCopyToReg(Chain, X86::ESI, Op.getOperand(2), InFlag);
InFlag = Chain.getValue(1);
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::Other);
Tys.push_back(MVT::Flag);
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(DAG.getValueType(AVT));
Ops.push_back(InFlag);
Chain = DAG.getNode(X86ISD::REP_MOVS, Tys, Ops);
if (TwoRepMovs) {
InFlag = Chain.getValue(1);
Count = Op.getOperand(3);
MVT::ValueType CVT = Count.getValueType();
SDOperand Left = DAG.getNode(ISD::AND, CVT, Count,
DAG.getConstant(3, CVT));
Chain = DAG.getCopyToReg(Chain, X86::ECX, Left, InFlag);
InFlag = Chain.getValue(1);
Tys.clear();
Tys.push_back(MVT::Other);
Tys.push_back(MVT::Flag);
Ops.clear();
Ops.push_back(Chain);
Ops.push_back(DAG.getValueType(MVT::i8));
Ops.push_back(InFlag);
Chain = DAG.getNode(X86ISD::REP_MOVS, Tys, Ops);
} else if (BytesLeft) {
// Issue loads and stores for the last 1 - 3 bytes.
unsigned Offset = I->getValue() - BytesLeft;
SDOperand DstAddr = Op.getOperand(1);
MVT::ValueType DstVT = DstAddr.getValueType();
SDOperand SrcAddr = Op.getOperand(2);
MVT::ValueType SrcVT = SrcAddr.getValueType();
SDOperand Value;
if (BytesLeft >= 2) {
Value = DAG.getLoad(MVT::i16, Chain,
DAG.getNode(ISD::ADD, SrcVT, SrcAddr,
DAG.getConstant(Offset, SrcVT)),
DAG.getSrcValue(NULL));
Chain = Value.getValue(1);
Chain = DAG.getNode(ISD::STORE, MVT::Other, Chain, Value,
DAG.getNode(ISD::ADD, DstVT, DstAddr,
DAG.getConstant(Offset, DstVT)),
DAG.getSrcValue(NULL));
BytesLeft -= 2;
Offset += 2;
}
if (BytesLeft == 1) {
Value = DAG.getLoad(MVT::i8, Chain,
DAG.getNode(ISD::ADD, SrcVT, SrcAddr,
DAG.getConstant(Offset, SrcVT)),
DAG.getSrcValue(NULL));
Chain = Value.getValue(1);
Chain = DAG.getNode(ISD::STORE, MVT::Other, Chain, Value,
DAG.getNode(ISD::ADD, DstVT, DstAddr,
DAG.getConstant(Offset, DstVT)),
DAG.getSrcValue(NULL));
}
}
return Chain;
}
// ConstantPool, GlobalAddress, and ExternalSymbol are lowered as their
// target countpart wrapped in the X86ISD::Wrapper node. Suppose N is
// one of the above mentioned nodes. It has to be wrapped because otherwise
// Select(N) returns N. So the raw TargetGlobalAddress nodes, etc. can only
// be used to form addressing mode. These wrapped nodes will be selected
// into MOV32ri.
case ISD::ConstantPool: {
ConstantPoolSDNode *CP = cast<ConstantPoolSDNode>(Op);
SDOperand Result = DAG.getNode(X86ISD::Wrapper, getPointerTy(),
DAG.getTargetConstantPool(CP->get(), getPointerTy(),
CP->getAlignment()));
if (getTargetMachine().getSubtarget<X86Subtarget>().isTargetDarwin()) {
// With PIC, the address is actually $g + Offset.
if (getTargetMachine().getRelocationModel() == Reloc::PIC)
Result = DAG.getNode(ISD::ADD, getPointerTy(),
DAG.getNode(X86ISD::GlobalBaseReg, getPointerTy()), Result);
}
return Result;
}
case ISD::GlobalAddress: {
GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
SDOperand Result = DAG.getNode(X86ISD::Wrapper, getPointerTy(),
DAG.getTargetGlobalAddress(GV, getPointerTy()));
if (getTargetMachine().
getSubtarget<X86Subtarget>().isTargetDarwin()) {
// With PIC, the address is actually $g + Offset.
if (getTargetMachine().getRelocationModel() == Reloc::PIC)
Result = DAG.getNode(ISD::ADD, getPointerTy(),
DAG.getNode(X86ISD::GlobalBaseReg, getPointerTy()), Result);
// For Darwin, external and weak symbols are indirect, so we want to load
// the value at address GV, not the value of GV itself. This means that
// the GlobalAddress must be in the base or index register of the address,
// not the GV offset field.
if (getTargetMachine().getRelocationModel() != Reloc::Static &&
DarwinGVRequiresExtraLoad(GV))
Result = DAG.getLoad(MVT::i32, DAG.getEntryNode(),
Result, DAG.getSrcValue(NULL));
}
return Result;
}
case ISD::ExternalSymbol: {
const char *Sym = cast<ExternalSymbolSDNode>(Op)->getSymbol();
SDOperand Result = DAG.getNode(X86ISD::Wrapper, getPointerTy(),
DAG.getTargetExternalSymbol(Sym, getPointerTy()));
if (getTargetMachine().
getSubtarget<X86Subtarget>().isTargetDarwin()) {
// With PIC, the address is actually $g + Offset.
if (getTargetMachine().getRelocationModel() == Reloc::PIC)
Result = DAG.getNode(ISD::ADD, getPointerTy(),
DAG.getNode(X86ISD::GlobalBaseReg, getPointerTy()), Result);
}
return Result;
}
case ISD::VASTART: {
// vastart just stores the address of the VarArgsFrameIndex slot into the
// memory location argument.
// FIXME: Replace MVT::i32 with PointerTy
SDOperand FR = DAG.getFrameIndex(VarArgsFrameIndex, MVT::i32);
return DAG.getNode(ISD::STORE, MVT::Other, Op.getOperand(0), FR,
Op.getOperand(1), Op.getOperand(2));
}
case ISD::RET: {
SDOperand Copy;
switch(Op.getNumOperands()) {
default:
assert(0 && "Do not know how to return this many arguments!");
abort();
case 1:
return DAG.getNode(X86ISD::RET_FLAG, MVT::Other, Op.getOperand(0),
DAG.getConstant(getBytesToPopOnReturn(), MVT::i16));
case 2: {
MVT::ValueType ArgVT = Op.getOperand(1).getValueType();
if (MVT::isInteger(ArgVT))
Copy = DAG.getCopyToReg(Op.getOperand(0), X86::EAX, Op.getOperand(1),
SDOperand());
else if (!X86ScalarSSE) {
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::Other);
Tys.push_back(MVT::Flag);
std::vector<SDOperand> Ops;
Ops.push_back(Op.getOperand(0));
Ops.push_back(Op.getOperand(1));
Copy = DAG.getNode(X86ISD::FP_SET_RESULT, Tys, Ops);
} else {
SDOperand MemLoc;
SDOperand Chain = Op.getOperand(0);
SDOperand Value = Op.getOperand(1);
if (Value.getOpcode() == ISD::LOAD &&
(Chain == Value.getValue(1) || Chain == Value.getOperand(0))) {
Chain = Value.getOperand(0);
MemLoc = Value.getOperand(1);
} else {
// Spill the value to memory and reload it into top of stack.
unsigned Size = MVT::getSizeInBits(ArgVT)/8;
MachineFunction &MF = DAG.getMachineFunction();
int SSFI = MF.getFrameInfo()->CreateStackObject(Size, Size);
MemLoc = DAG.getFrameIndex(SSFI, getPointerTy());
Chain = DAG.getNode(ISD::STORE, MVT::Other, Op.getOperand(0),
Value, MemLoc, DAG.getSrcValue(0));
}
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::f64);
Tys.push_back(MVT::Other);
std::vector<SDOperand> Ops;
Ops.push_back(Chain);
Ops.push_back(MemLoc);
Ops.push_back(DAG.getValueType(ArgVT));
Copy = DAG.getNode(X86ISD::FLD, Tys, Ops);
Tys.clear();
Tys.push_back(MVT::Other);
Tys.push_back(MVT::Flag);
Ops.clear();
Ops.push_back(Copy.getValue(1));
Ops.push_back(Copy);
Copy = DAG.getNode(X86ISD::FP_SET_RESULT, Tys, Ops);
}
break;
}
case 3:
Copy = DAG.getCopyToReg(Op.getOperand(0), X86::EDX, Op.getOperand(2),
SDOperand());
Copy = DAG.getCopyToReg(Copy, X86::EAX,Op.getOperand(1),Copy.getValue(1));
break;
}
return DAG.getNode(X86ISD::RET_FLAG, MVT::Other,
Copy, DAG.getConstant(getBytesToPopOnReturn(), MVT::i16),
Copy.getValue(1));
}
}
}
const char *X86TargetLowering::getTargetNodeName(unsigned Opcode) const {
switch (Opcode) {
default: return NULL;
case X86ISD::SHLD: return "X86ISD::SHLD";
case X86ISD::SHRD: return "X86ISD::SHRD";
case X86ISD::FAND: return "X86ISD::FAND";
case X86ISD::FXOR: return "X86ISD::FXOR";
case X86ISD::FILD: return "X86ISD::FILD";
case X86ISD::FILD_FLAG: return "X86ISD::FILD_FLAG";
case X86ISD::FP_TO_INT16_IN_MEM: return "X86ISD::FP_TO_INT16_IN_MEM";
case X86ISD::FP_TO_INT32_IN_MEM: return "X86ISD::FP_TO_INT32_IN_MEM";
case X86ISD::FP_TO_INT64_IN_MEM: return "X86ISD::FP_TO_INT64_IN_MEM";
case X86ISD::FLD: return "X86ISD::FLD";
case X86ISD::FST: return "X86ISD::FST";
case X86ISD::FP_GET_RESULT: return "X86ISD::FP_GET_RESULT";
case X86ISD::FP_SET_RESULT: return "X86ISD::FP_SET_RESULT";
case X86ISD::CALL: return "X86ISD::CALL";
case X86ISD::TAILCALL: return "X86ISD::TAILCALL";
case X86ISD::RDTSC_DAG: return "X86ISD::RDTSC_DAG";
case X86ISD::CMP: return "X86ISD::CMP";
case X86ISD::TEST: return "X86ISD::TEST";
case X86ISD::SETCC: return "X86ISD::SETCC";
case X86ISD::CMOV: return "X86ISD::CMOV";
case X86ISD::BRCOND: return "X86ISD::BRCOND";
case X86ISD::RET_FLAG: return "X86ISD::RET_FLAG";
case X86ISD::REP_STOS: return "X86ISD::REP_STOS";
case X86ISD::REP_MOVS: return "X86ISD::REP_MOVS";
case X86ISD::LOAD_PACK: return "X86ISD::LOAD_PACK";
case X86ISD::GlobalBaseReg: return "X86ISD::GlobalBaseReg";
case X86ISD::Wrapper: return "X86ISD::Wrapper";
}
}
void X86TargetLowering::computeMaskedBitsForTargetNode(const SDOperand Op,
uint64_t Mask,
uint64_t &KnownZero,
uint64_t &KnownOne,
unsigned Depth) const {
unsigned Opc = Op.getOpcode();
KnownZero = KnownOne = 0; // Don't know anything.
switch (Opc) {
default:
assert(Opc >= ISD::BUILTIN_OP_END && "Expected a target specific node");
break;
case X86ISD::SETCC:
KnownZero |= (MVT::getIntVTBitMask(Op.getValueType()) ^ 1ULL);
break;
}
}
std::vector<unsigned> X86TargetLowering::
getRegClassForInlineAsmConstraint(const std::string &Constraint,
MVT::ValueType VT) const {
if (Constraint.size() == 1) {
// FIXME: not handling fp-stack yet!
// FIXME: not handling MMX registers yet ('y' constraint).
switch (Constraint[0]) { // GCC X86 Constraint Letters
default: break; // Unknown constriant letter
case 'r': // GENERAL_REGS
case 'R': // LEGACY_REGS
return make_vector<unsigned>(X86::EAX, X86::EBX, X86::ECX, X86::EDX,
X86::ESI, X86::EDI, X86::EBP, X86::ESP, 0);
case 'l': // INDEX_REGS
return make_vector<unsigned>(X86::EAX, X86::EBX, X86::ECX, X86::EDX,
X86::ESI, X86::EDI, X86::EBP, 0);
case 'q': // Q_REGS (GENERAL_REGS in 64-bit mode)
case 'Q': // Q_REGS
return make_vector<unsigned>(X86::EAX, X86::EBX, X86::ECX, X86::EDX, 0);
case 'x': // SSE_REGS if SSE1 allowed
if (Subtarget->hasSSE1())
return make_vector<unsigned>(X86::XMM0, X86::XMM1, X86::XMM2, X86::XMM3,
X86::XMM4, X86::XMM5, X86::XMM6, X86::XMM7,
0);
return std::vector<unsigned>();
case 'Y': // SSE_REGS if SSE2 allowed
if (Subtarget->hasSSE2())
return make_vector<unsigned>(X86::XMM0, X86::XMM1, X86::XMM2, X86::XMM3,
X86::XMM4, X86::XMM5, X86::XMM6, X86::XMM7,
0);
return std::vector<unsigned>();
}
}
return std::vector<unsigned>();
}
/// isLegalAddressImmediate - Return true if the integer value or
/// GlobalValue can be used as the offset of the target addressing mode.
bool X86TargetLowering::isLegalAddressImmediate(int64_t V) const {
// X86 allows a sign-extended 32-bit immediate field.
return (V > -(1LL << 32) && V < (1LL << 32)-1);
}
bool X86TargetLowering::isLegalAddressImmediate(GlobalValue *GV) const {
if (getTargetMachine().
getSubtarget<X86Subtarget>().isTargetDarwin()) {
Reloc::Model RModel = getTargetMachine().getRelocationModel();
if (RModel == Reloc::Static)
return true;
else if (RModel == Reloc::DynamicNoPIC)
return !DarwinGVRequiresExtraLoad(GV);
else
return false;
} else
return true;
}