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X86FastISel.cpp
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//===-- X86FastISel.cpp - X86 FastISel implementation ---------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines the X86-specific support for the FastISel class. Much
// of the target-specific code is generated by tablegen in the file
// X86GenFastISel.inc, which is #included here.
//
//===----------------------------------------------------------------------===//
#include "X86.h"
#include "X86CallingConv.h"
#include "X86InstrBuilder.h"
#include "X86InstrInfo.h"
#include "X86MachineFunctionInfo.h"
#include "X86RegisterInfo.h"
#include "X86Subtarget.h"
#include "X86TargetMachine.h"
#include "llvm/Analysis/BranchProbabilityInfo.h"
#include "llvm/CodeGen/FastISel.h"
#include "llvm/CodeGen/FunctionLoweringInfo.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/IntrinsicsX86.h"
#include "llvm/IR/Operator.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
namespace {
class X86FastISel final : public FastISel {
/// Subtarget - Keep a pointer to the X86Subtarget around so that we can
/// make the right decision when generating code for different targets.
const X86Subtarget *Subtarget;
/// X86ScalarSSEf32, X86ScalarSSEf64 - Select between SSE or x87
/// floating point ops.
/// When SSE is available, use it for f32 operations.
/// When SSE2 is available, use it for f64 operations.
bool X86ScalarSSEf64;
bool X86ScalarSSEf32;
public:
explicit X86FastISel(FunctionLoweringInfo &funcInfo,
const TargetLibraryInfo *libInfo)
: FastISel(funcInfo, libInfo) {
Subtarget = &funcInfo.MF->getSubtarget<X86Subtarget>();
X86ScalarSSEf64 = Subtarget->hasSSE2();
X86ScalarSSEf32 = Subtarget->hasSSE1();
}
bool fastSelectInstruction(const Instruction *I) override;
/// The specified machine instr operand is a vreg, and that
/// vreg is being provided by the specified load instruction. If possible,
/// try to fold the load as an operand to the instruction, returning true if
/// possible.
bool tryToFoldLoadIntoMI(MachineInstr *MI, unsigned OpNo,
const LoadInst *LI) override;
bool fastLowerArguments() override;
bool fastLowerCall(CallLoweringInfo &CLI) override;
bool fastLowerIntrinsicCall(const IntrinsicInst *II) override;
#include "X86GenFastISel.inc"
private:
bool X86FastEmitCompare(const Value *LHS, const Value *RHS, EVT VT,
const DebugLoc &DL);
bool X86FastEmitLoad(MVT VT, X86AddressMode &AM, MachineMemOperand *MMO,
unsigned &ResultReg, unsigned Alignment = 1);
bool X86FastEmitStore(EVT VT, const Value *Val, X86AddressMode &AM,
MachineMemOperand *MMO = nullptr, bool Aligned = false);
bool X86FastEmitStore(EVT VT, unsigned ValReg, X86AddressMode &AM,
MachineMemOperand *MMO = nullptr, bool Aligned = false);
bool X86FastEmitExtend(ISD::NodeType Opc, EVT DstVT, unsigned Src, EVT SrcVT,
unsigned &ResultReg);
bool X86SelectAddress(const Value *V, X86AddressMode &AM);
bool X86SelectCallAddress(const Value *V, X86AddressMode &AM);
bool X86SelectLoad(const Instruction *I);
bool X86SelectStore(const Instruction *I);
bool X86SelectRet(const Instruction *I);
bool X86SelectCmp(const Instruction *I);
bool X86SelectZExt(const Instruction *I);
bool X86SelectSExt(const Instruction *I);
bool X86SelectBranch(const Instruction *I);
bool X86SelectShift(const Instruction *I);
bool X86SelectDivRem(const Instruction *I);
bool X86FastEmitCMoveSelect(MVT RetVT, const Instruction *I);
bool X86FastEmitSSESelect(MVT RetVT, const Instruction *I);
bool X86FastEmitPseudoSelect(MVT RetVT, const Instruction *I);
bool X86SelectSelect(const Instruction *I);
bool X86SelectTrunc(const Instruction *I);
bool X86SelectFPExtOrFPTrunc(const Instruction *I, unsigned Opc,
const TargetRegisterClass *RC);
bool X86SelectFPExt(const Instruction *I);
bool X86SelectFPTrunc(const Instruction *I);
bool X86SelectSIToFP(const Instruction *I);
bool X86SelectUIToFP(const Instruction *I);
bool X86SelectIntToFP(const Instruction *I, bool IsSigned);
const X86InstrInfo *getInstrInfo() const {
return Subtarget->getInstrInfo();
}
const X86TargetMachine *getTargetMachine() const {
return static_cast<const X86TargetMachine *>(&TM);
}
bool handleConstantAddresses(const Value *V, X86AddressMode &AM);
unsigned X86MaterializeInt(const ConstantInt *CI, MVT VT);
unsigned X86MaterializeFP(const ConstantFP *CFP, MVT VT);
unsigned X86MaterializeGV(const GlobalValue *GV, MVT VT);
unsigned fastMaterializeConstant(const Constant *C) override;
unsigned fastMaterializeAlloca(const AllocaInst *C) override;
unsigned fastMaterializeFloatZero(const ConstantFP *CF) override;
/// isScalarFPTypeInSSEReg - Return true if the specified scalar FP type is
/// computed in an SSE register, not on the X87 floating point stack.
bool isScalarFPTypeInSSEReg(EVT VT) const {
return (VT == MVT::f64 && X86ScalarSSEf64) || // f64 is when SSE2
(VT == MVT::f32 && X86ScalarSSEf32); // f32 is when SSE1
}
bool isTypeLegal(Type *Ty, MVT &VT, bool AllowI1 = false);
bool IsMemcpySmall(uint64_t Len);
bool TryEmitSmallMemcpy(X86AddressMode DestAM,
X86AddressMode SrcAM, uint64_t Len);
bool foldX86XALUIntrinsic(X86::CondCode &CC, const Instruction *I,
const Value *Cond);
const MachineInstrBuilder &addFullAddress(const MachineInstrBuilder &MIB,
X86AddressMode &AM);
unsigned fastEmitInst_rrrr(unsigned MachineInstOpcode,
const TargetRegisterClass *RC, unsigned Op0,
unsigned Op1, unsigned Op2, unsigned Op3);
};
} // end anonymous namespace.
static std::pair<unsigned, bool>
getX86SSEConditionCode(CmpInst::Predicate Predicate) {
unsigned CC;
bool NeedSwap = false;
// SSE Condition code mapping:
// 0 - EQ
// 1 - LT
// 2 - LE
// 3 - UNORD
// 4 - NEQ
// 5 - NLT
// 6 - NLE
// 7 - ORD
switch (Predicate) {
default: llvm_unreachable("Unexpected predicate");
case CmpInst::FCMP_OEQ: CC = 0; break;
case CmpInst::FCMP_OGT: NeedSwap = true; LLVM_FALLTHROUGH;
case CmpInst::FCMP_OLT: CC = 1; break;
case CmpInst::FCMP_OGE: NeedSwap = true; LLVM_FALLTHROUGH;
case CmpInst::FCMP_OLE: CC = 2; break;
case CmpInst::FCMP_UNO: CC = 3; break;
case CmpInst::FCMP_UNE: CC = 4; break;
case CmpInst::FCMP_ULE: NeedSwap = true; LLVM_FALLTHROUGH;
case CmpInst::FCMP_UGE: CC = 5; break;
case CmpInst::FCMP_ULT: NeedSwap = true; LLVM_FALLTHROUGH;
case CmpInst::FCMP_UGT: CC = 6; break;
case CmpInst::FCMP_ORD: CC = 7; break;
case CmpInst::FCMP_UEQ: CC = 8; break;
case CmpInst::FCMP_ONE: CC = 12; break;
}
return std::make_pair(CC, NeedSwap);
}
/// Adds a complex addressing mode to the given machine instr builder.
/// Note, this will constrain the index register. If its not possible to
/// constrain the given index register, then a new one will be created. The
/// IndexReg field of the addressing mode will be updated to match in this case.
const MachineInstrBuilder &
X86FastISel::addFullAddress(const MachineInstrBuilder &MIB,
X86AddressMode &AM) {
// First constrain the index register. It needs to be a GR64_NOSP.
AM.IndexReg = constrainOperandRegClass(MIB->getDesc(), AM.IndexReg,
MIB->getNumOperands() +
X86::AddrIndexReg);
return ::addFullAddress(MIB, AM);
}
/// Check if it is possible to fold the condition from the XALU intrinsic
/// into the user. The condition code will only be updated on success.
bool X86FastISel::foldX86XALUIntrinsic(X86::CondCode &CC, const Instruction *I,
const Value *Cond) {
if (!isa<ExtractValueInst>(Cond))
return false;
const auto *EV = cast<ExtractValueInst>(Cond);
if (!isa<IntrinsicInst>(EV->getAggregateOperand()))
return false;
const auto *II = cast<IntrinsicInst>(EV->getAggregateOperand());
MVT RetVT;
const Function *Callee = II->getCalledFunction();
Type *RetTy =
cast<StructType>(Callee->getReturnType())->getTypeAtIndex(0U);
if (!isTypeLegal(RetTy, RetVT))
return false;
if (RetVT != MVT::i32 && RetVT != MVT::i64)
return false;
X86::CondCode TmpCC;
switch (II->getIntrinsicID()) {
default: return false;
case Intrinsic::sadd_with_overflow:
case Intrinsic::ssub_with_overflow:
case Intrinsic::smul_with_overflow:
case Intrinsic::umul_with_overflow: TmpCC = X86::COND_O; break;
case Intrinsic::uadd_with_overflow:
case Intrinsic::usub_with_overflow: TmpCC = X86::COND_B; break;
}
// Check if both instructions are in the same basic block.
if (II->getParent() != I->getParent())
return false;
// Make sure nothing is in the way
BasicBlock::const_iterator Start(I);
BasicBlock::const_iterator End(II);
for (auto Itr = std::prev(Start); Itr != End; --Itr) {
// We only expect extractvalue instructions between the intrinsic and the
// instruction to be selected.
if (!isa<ExtractValueInst>(Itr))
return false;
// Check that the extractvalue operand comes from the intrinsic.
const auto *EVI = cast<ExtractValueInst>(Itr);
if (EVI->getAggregateOperand() != II)
return false;
}
// Make sure no potentially eflags clobbering phi moves can be inserted in
// between.
auto HasPhis = [](const BasicBlock *Succ) {
return !llvm::empty(Succ->phis());
};
if (I->isTerminator() && llvm::any_of(successors(I), HasPhis))
return false;
CC = TmpCC;
return true;
}
bool X86FastISel::isTypeLegal(Type *Ty, MVT &VT, bool AllowI1) {
EVT evt = TLI.getValueType(DL, Ty, /*AllowUnknown=*/true);
if (evt == MVT::Other || !evt.isSimple())
// Unhandled type. Halt "fast" selection and bail.
return false;
VT = evt.getSimpleVT();
// For now, require SSE/SSE2 for performing floating-point operations,
// since x87 requires additional work.
if (VT == MVT::f64 && !X86ScalarSSEf64)
return false;
if (VT == MVT::f32 && !X86ScalarSSEf32)
return false;
// Similarly, no f80 support yet.
if (VT == MVT::f80)
return false;
// We only handle legal types. For example, on x86-32 the instruction
// selector contains all of the 64-bit instructions from x86-64,
// under the assumption that i64 won't be used if the target doesn't
// support it.
return (AllowI1 && VT == MVT::i1) || TLI.isTypeLegal(VT);
}
/// X86FastEmitLoad - Emit a machine instruction to load a value of type VT.
/// The address is either pre-computed, i.e. Ptr, or a GlobalAddress, i.e. GV.
/// Return true and the result register by reference if it is possible.
bool X86FastISel::X86FastEmitLoad(MVT VT, X86AddressMode &AM,
MachineMemOperand *MMO, unsigned &ResultReg,
unsigned Alignment) {
bool HasSSE41 = Subtarget->hasSSE41();
bool HasAVX = Subtarget->hasAVX();
bool HasAVX2 = Subtarget->hasAVX2();
bool HasAVX512 = Subtarget->hasAVX512();
bool HasVLX = Subtarget->hasVLX();
bool IsNonTemporal = MMO && MMO->isNonTemporal();
// Treat i1 loads the same as i8 loads. Masking will be done when storing.
if (VT == MVT::i1)
VT = MVT::i8;
// Get opcode and regclass of the output for the given load instruction.
unsigned Opc = 0;
switch (VT.SimpleTy) {
default: return false;
case MVT::i8:
Opc = X86::MOV8rm;
break;
case MVT::i16:
Opc = X86::MOV16rm;
break;
case MVT::i32:
Opc = X86::MOV32rm;
break;
case MVT::i64:
// Must be in x86-64 mode.
Opc = X86::MOV64rm;
break;
case MVT::f32:
if (X86ScalarSSEf32)
Opc = HasAVX512 ? X86::VMOVSSZrm_alt :
HasAVX ? X86::VMOVSSrm_alt :
X86::MOVSSrm_alt;
else
Opc = X86::LD_Fp32m;
break;
case MVT::f64:
if (X86ScalarSSEf64)
Opc = HasAVX512 ? X86::VMOVSDZrm_alt :
HasAVX ? X86::VMOVSDrm_alt :
X86::MOVSDrm_alt;
else
Opc = X86::LD_Fp64m;
break;
case MVT::f80:
// No f80 support yet.
return false;
case MVT::v4f32:
if (IsNonTemporal && Alignment >= 16 && HasSSE41)
Opc = HasVLX ? X86::VMOVNTDQAZ128rm :
HasAVX ? X86::VMOVNTDQArm : X86::MOVNTDQArm;
else if (Alignment >= 16)
Opc = HasVLX ? X86::VMOVAPSZ128rm :
HasAVX ? X86::VMOVAPSrm : X86::MOVAPSrm;
else
Opc = HasVLX ? X86::VMOVUPSZ128rm :
HasAVX ? X86::VMOVUPSrm : X86::MOVUPSrm;
break;
case MVT::v2f64:
if (IsNonTemporal && Alignment >= 16 && HasSSE41)
Opc = HasVLX ? X86::VMOVNTDQAZ128rm :
HasAVX ? X86::VMOVNTDQArm : X86::MOVNTDQArm;
else if (Alignment >= 16)
Opc = HasVLX ? X86::VMOVAPDZ128rm :
HasAVX ? X86::VMOVAPDrm : X86::MOVAPDrm;
else
Opc = HasVLX ? X86::VMOVUPDZ128rm :
HasAVX ? X86::VMOVUPDrm : X86::MOVUPDrm;
break;
case MVT::v4i32:
case MVT::v2i64:
case MVT::v8i16:
case MVT::v16i8:
if (IsNonTemporal && Alignment >= 16 && HasSSE41)
Opc = HasVLX ? X86::VMOVNTDQAZ128rm :
HasAVX ? X86::VMOVNTDQArm : X86::MOVNTDQArm;
else if (Alignment >= 16)
Opc = HasVLX ? X86::VMOVDQA64Z128rm :
HasAVX ? X86::VMOVDQArm : X86::MOVDQArm;
else
Opc = HasVLX ? X86::VMOVDQU64Z128rm :
HasAVX ? X86::VMOVDQUrm : X86::MOVDQUrm;
break;
case MVT::v8f32:
assert(HasAVX);
if (IsNonTemporal && Alignment >= 32 && HasAVX2)
Opc = HasVLX ? X86::VMOVNTDQAZ256rm : X86::VMOVNTDQAYrm;
else if (IsNonTemporal && Alignment >= 16)
return false; // Force split for X86::VMOVNTDQArm
else if (Alignment >= 32)
Opc = HasVLX ? X86::VMOVAPSZ256rm : X86::VMOVAPSYrm;
else
Opc = HasVLX ? X86::VMOVUPSZ256rm : X86::VMOVUPSYrm;
break;
case MVT::v4f64:
assert(HasAVX);
if (IsNonTemporal && Alignment >= 32 && HasAVX2)
Opc = HasVLX ? X86::VMOVNTDQAZ256rm : X86::VMOVNTDQAYrm;
else if (IsNonTemporal && Alignment >= 16)
return false; // Force split for X86::VMOVNTDQArm
else if (Alignment >= 32)
Opc = HasVLX ? X86::VMOVAPDZ256rm : X86::VMOVAPDYrm;
else
Opc = HasVLX ? X86::VMOVUPDZ256rm : X86::VMOVUPDYrm;
break;
case MVT::v8i32:
case MVT::v4i64:
case MVT::v16i16:
case MVT::v32i8:
assert(HasAVX);
if (IsNonTemporal && Alignment >= 32 && HasAVX2)
Opc = HasVLX ? X86::VMOVNTDQAZ256rm : X86::VMOVNTDQAYrm;
else if (IsNonTemporal && Alignment >= 16)
return false; // Force split for X86::VMOVNTDQArm
else if (Alignment >= 32)
Opc = HasVLX ? X86::VMOVDQA64Z256rm : X86::VMOVDQAYrm;
else
Opc = HasVLX ? X86::VMOVDQU64Z256rm : X86::VMOVDQUYrm;
break;
case MVT::v16f32:
assert(HasAVX512);
if (IsNonTemporal && Alignment >= 64)
Opc = X86::VMOVNTDQAZrm;
else
Opc = (Alignment >= 64) ? X86::VMOVAPSZrm : X86::VMOVUPSZrm;
break;
case MVT::v8f64:
assert(HasAVX512);
if (IsNonTemporal && Alignment >= 64)
Opc = X86::VMOVNTDQAZrm;
else
Opc = (Alignment >= 64) ? X86::VMOVAPDZrm : X86::VMOVUPDZrm;
break;
case MVT::v8i64:
case MVT::v16i32:
case MVT::v32i16:
case MVT::v64i8:
assert(HasAVX512);
// Note: There are a lot more choices based on type with AVX-512, but
// there's really no advantage when the load isn't masked.
if (IsNonTemporal && Alignment >= 64)
Opc = X86::VMOVNTDQAZrm;
else
Opc = (Alignment >= 64) ? X86::VMOVDQA64Zrm : X86::VMOVDQU64Zrm;
break;
}
const TargetRegisterClass *RC = TLI.getRegClassFor(VT);
ResultReg = createResultReg(RC);
MachineInstrBuilder MIB =
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc), ResultReg);
addFullAddress(MIB, AM);
if (MMO)
MIB->addMemOperand(*FuncInfo.MF, MMO);
return true;
}
/// X86FastEmitStore - Emit a machine instruction to store a value Val of
/// type VT. The address is either pre-computed, consisted of a base ptr, Ptr
/// and a displacement offset, or a GlobalAddress,
/// i.e. V. Return true if it is possible.
bool X86FastISel::X86FastEmitStore(EVT VT, unsigned ValReg, X86AddressMode &AM,
MachineMemOperand *MMO, bool Aligned) {
bool HasSSE1 = Subtarget->hasSSE1();
bool HasSSE2 = Subtarget->hasSSE2();
bool HasSSE4A = Subtarget->hasSSE4A();
bool HasAVX = Subtarget->hasAVX();
bool HasAVX512 = Subtarget->hasAVX512();
bool HasVLX = Subtarget->hasVLX();
bool IsNonTemporal = MMO && MMO->isNonTemporal();
// Get opcode and regclass of the output for the given store instruction.
unsigned Opc = 0;
switch (VT.getSimpleVT().SimpleTy) {
case MVT::f80: // No f80 support yet.
default: return false;
case MVT::i1: {
// Mask out all but lowest bit.
Register AndResult = createResultReg(&X86::GR8RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(X86::AND8ri), AndResult)
.addReg(ValReg).addImm(1);
ValReg = AndResult;
LLVM_FALLTHROUGH; // handle i1 as i8.
}
case MVT::i8: Opc = X86::MOV8mr; break;
case MVT::i16: Opc = X86::MOV16mr; break;
case MVT::i32:
Opc = (IsNonTemporal && HasSSE2) ? X86::MOVNTImr : X86::MOV32mr;
break;
case MVT::i64:
// Must be in x86-64 mode.
Opc = (IsNonTemporal && HasSSE2) ? X86::MOVNTI_64mr : X86::MOV64mr;
break;
case MVT::f32:
if (X86ScalarSSEf32) {
if (IsNonTemporal && HasSSE4A)
Opc = X86::MOVNTSS;
else
Opc = HasAVX512 ? X86::VMOVSSZmr :
HasAVX ? X86::VMOVSSmr : X86::MOVSSmr;
} else
Opc = X86::ST_Fp32m;
break;
case MVT::f64:
if (X86ScalarSSEf32) {
if (IsNonTemporal && HasSSE4A)
Opc = X86::MOVNTSD;
else
Opc = HasAVX512 ? X86::VMOVSDZmr :
HasAVX ? X86::VMOVSDmr : X86::MOVSDmr;
} else
Opc = X86::ST_Fp64m;
break;
case MVT::x86mmx:
Opc = (IsNonTemporal && HasSSE1) ? X86::MMX_MOVNTQmr : X86::MMX_MOVQ64mr;
break;
case MVT::v4f32:
if (Aligned) {
if (IsNonTemporal)
Opc = HasVLX ? X86::VMOVNTPSZ128mr :
HasAVX ? X86::VMOVNTPSmr : X86::MOVNTPSmr;
else
Opc = HasVLX ? X86::VMOVAPSZ128mr :
HasAVX ? X86::VMOVAPSmr : X86::MOVAPSmr;
} else
Opc = HasVLX ? X86::VMOVUPSZ128mr :
HasAVX ? X86::VMOVUPSmr : X86::MOVUPSmr;
break;
case MVT::v2f64:
if (Aligned) {
if (IsNonTemporal)
Opc = HasVLX ? X86::VMOVNTPDZ128mr :
HasAVX ? X86::VMOVNTPDmr : X86::MOVNTPDmr;
else
Opc = HasVLX ? X86::VMOVAPDZ128mr :
HasAVX ? X86::VMOVAPDmr : X86::MOVAPDmr;
} else
Opc = HasVLX ? X86::VMOVUPDZ128mr :
HasAVX ? X86::VMOVUPDmr : X86::MOVUPDmr;
break;
case MVT::v4i32:
case MVT::v2i64:
case MVT::v8i16:
case MVT::v16i8:
if (Aligned) {
if (IsNonTemporal)
Opc = HasVLX ? X86::VMOVNTDQZ128mr :
HasAVX ? X86::VMOVNTDQmr : X86::MOVNTDQmr;
else
Opc = HasVLX ? X86::VMOVDQA64Z128mr :
HasAVX ? X86::VMOVDQAmr : X86::MOVDQAmr;
} else
Opc = HasVLX ? X86::VMOVDQU64Z128mr :
HasAVX ? X86::VMOVDQUmr : X86::MOVDQUmr;
break;
case MVT::v8f32:
assert(HasAVX);
if (Aligned) {
if (IsNonTemporal)
Opc = HasVLX ? X86::VMOVNTPSZ256mr : X86::VMOVNTPSYmr;
else
Opc = HasVLX ? X86::VMOVAPSZ256mr : X86::VMOVAPSYmr;
} else
Opc = HasVLX ? X86::VMOVUPSZ256mr : X86::VMOVUPSYmr;
break;
case MVT::v4f64:
assert(HasAVX);
if (Aligned) {
if (IsNonTemporal)
Opc = HasVLX ? X86::VMOVNTPDZ256mr : X86::VMOVNTPDYmr;
else
Opc = HasVLX ? X86::VMOVAPDZ256mr : X86::VMOVAPDYmr;
} else
Opc = HasVLX ? X86::VMOVUPDZ256mr : X86::VMOVUPDYmr;
break;
case MVT::v8i32:
case MVT::v4i64:
case MVT::v16i16:
case MVT::v32i8:
assert(HasAVX);
if (Aligned) {
if (IsNonTemporal)
Opc = HasVLX ? X86::VMOVNTDQZ256mr : X86::VMOVNTDQYmr;
else
Opc = HasVLX ? X86::VMOVDQA64Z256mr : X86::VMOVDQAYmr;
} else
Opc = HasVLX ? X86::VMOVDQU64Z256mr : X86::VMOVDQUYmr;
break;
case MVT::v16f32:
assert(HasAVX512);
if (Aligned)
Opc = IsNonTemporal ? X86::VMOVNTPSZmr : X86::VMOVAPSZmr;
else
Opc = X86::VMOVUPSZmr;
break;
case MVT::v8f64:
assert(HasAVX512);
if (Aligned) {
Opc = IsNonTemporal ? X86::VMOVNTPDZmr : X86::VMOVAPDZmr;
} else
Opc = X86::VMOVUPDZmr;
break;
case MVT::v8i64:
case MVT::v16i32:
case MVT::v32i16:
case MVT::v64i8:
assert(HasAVX512);
// Note: There are a lot more choices based on type with AVX-512, but
// there's really no advantage when the store isn't masked.
if (Aligned)
Opc = IsNonTemporal ? X86::VMOVNTDQZmr : X86::VMOVDQA64Zmr;
else
Opc = X86::VMOVDQU64Zmr;
break;
}
const MCInstrDesc &Desc = TII.get(Opc);
// Some of the instructions in the previous switch use FR128 instead
// of FR32 for ValReg. Make sure the register we feed the instruction
// matches its register class constraints.
// Note: This is fine to do a copy from FR32 to FR128, this is the
// same registers behind the scene and actually why it did not trigger
// any bugs before.
ValReg = constrainOperandRegClass(Desc, ValReg, Desc.getNumOperands() - 1);
MachineInstrBuilder MIB =
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, Desc);
addFullAddress(MIB, AM).addReg(ValReg);
if (MMO)
MIB->addMemOperand(*FuncInfo.MF, MMO);
return true;
}
bool X86FastISel::X86FastEmitStore(EVT VT, const Value *Val,
X86AddressMode &AM,
MachineMemOperand *MMO, bool Aligned) {
// Handle 'null' like i32/i64 0.
if (isa<ConstantPointerNull>(Val))
Val = Constant::getNullValue(DL.getIntPtrType(Val->getContext()));
// If this is a store of a simple constant, fold the constant into the store.
if (const ConstantInt *CI = dyn_cast<ConstantInt>(Val)) {
unsigned Opc = 0;
bool Signed = true;
switch (VT.getSimpleVT().SimpleTy) {
default: break;
case MVT::i1:
Signed = false;
LLVM_FALLTHROUGH; // Handle as i8.
case MVT::i8: Opc = X86::MOV8mi; break;
case MVT::i16: Opc = X86::MOV16mi; break;
case MVT::i32: Opc = X86::MOV32mi; break;
case MVT::i64:
// Must be a 32-bit sign extended value.
if (isInt<32>(CI->getSExtValue()))
Opc = X86::MOV64mi32;
break;
}
if (Opc) {
MachineInstrBuilder MIB =
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc));
addFullAddress(MIB, AM).addImm(Signed ? (uint64_t) CI->getSExtValue()
: CI->getZExtValue());
if (MMO)
MIB->addMemOperand(*FuncInfo.MF, MMO);
return true;
}
}
Register ValReg = getRegForValue(Val);
if (ValReg == 0)
return false;
return X86FastEmitStore(VT, ValReg, AM, MMO, Aligned);
}
/// X86FastEmitExtend - Emit a machine instruction to extend a value Src of
/// type SrcVT to type DstVT using the specified extension opcode Opc (e.g.
/// ISD::SIGN_EXTEND).
bool X86FastISel::X86FastEmitExtend(ISD::NodeType Opc, EVT DstVT,
unsigned Src, EVT SrcVT,
unsigned &ResultReg) {
unsigned RR = fastEmit_r(SrcVT.getSimpleVT(), DstVT.getSimpleVT(), Opc, Src);
if (RR == 0)
return false;
ResultReg = RR;
return true;
}
bool X86FastISel::handleConstantAddresses(const Value *V, X86AddressMode &AM) {
// Handle constant address.
if (const GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
// Can't handle alternate code models yet.
if (TM.getCodeModel() != CodeModel::Small)
return false;
// Can't handle TLS yet.
if (GV->isThreadLocal())
return false;
// Can't handle !absolute_symbol references yet.
if (GV->isAbsoluteSymbolRef())
return false;
// RIP-relative addresses can't have additional register operands, so if
// we've already folded stuff into the addressing mode, just force the
// global value into its own register, which we can use as the basereg.
if (!Subtarget->isPICStyleRIPRel() ||
(AM.Base.Reg == 0 && AM.IndexReg == 0)) {
// Okay, we've committed to selecting this global. Set up the address.
AM.GV = GV;
// Allow the subtarget to classify the global.
unsigned char GVFlags = Subtarget->classifyGlobalReference(GV);
// If this reference is relative to the pic base, set it now.
if (isGlobalRelativeToPICBase(GVFlags)) {
// FIXME: How do we know Base.Reg is free??
AM.Base.Reg = getInstrInfo()->getGlobalBaseReg(FuncInfo.MF);
}
// Unless the ABI requires an extra load, return a direct reference to
// the global.
if (!isGlobalStubReference(GVFlags)) {
if (Subtarget->isPICStyleRIPRel()) {
// Use rip-relative addressing if we can. Above we verified that the
// base and index registers are unused.
assert(AM.Base.Reg == 0 && AM.IndexReg == 0);
AM.Base.Reg = X86::RIP;
}
AM.GVOpFlags = GVFlags;
return true;
}
// Ok, we need to do a load from a stub. If we've already loaded from
// this stub, reuse the loaded pointer, otherwise emit the load now.
DenseMap<const Value *, Register>::iterator I = LocalValueMap.find(V);
Register LoadReg;
if (I != LocalValueMap.end() && I->second) {
LoadReg = I->second;
} else {
// Issue load from stub.
unsigned Opc = 0;
const TargetRegisterClass *RC = nullptr;
X86AddressMode StubAM;
StubAM.Base.Reg = AM.Base.Reg;
StubAM.GV = GV;
StubAM.GVOpFlags = GVFlags;
// Prepare for inserting code in the local-value area.
SavePoint SaveInsertPt = enterLocalValueArea();
if (TLI.getPointerTy(DL) == MVT::i64) {
Opc = X86::MOV64rm;
RC = &X86::GR64RegClass;
} else {
Opc = X86::MOV32rm;
RC = &X86::GR32RegClass;
}
if (Subtarget->isPICStyleRIPRel() || GVFlags == X86II::MO_GOTPCREL)
StubAM.Base.Reg = X86::RIP;
LoadReg = createResultReg(RC);
MachineInstrBuilder LoadMI =
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc), LoadReg);
addFullAddress(LoadMI, StubAM);
// Ok, back to normal mode.
leaveLocalValueArea(SaveInsertPt);
// Prevent loading GV stub multiple times in same MBB.
LocalValueMap[V] = LoadReg;
}
// Now construct the final address. Note that the Disp, Scale,
// and Index values may already be set here.
AM.Base.Reg = LoadReg;
AM.GV = nullptr;
return true;
}
}
// If all else fails, try to materialize the value in a register.
if (!AM.GV || !Subtarget->isPICStyleRIPRel()) {
if (AM.Base.Reg == 0) {
AM.Base.Reg = getRegForValue(V);
return AM.Base.Reg != 0;
}
if (AM.IndexReg == 0) {
assert(AM.Scale == 1 && "Scale with no index!");
AM.IndexReg = getRegForValue(V);
return AM.IndexReg != 0;
}
}
return false;
}
/// X86SelectAddress - Attempt to fill in an address from the given value.
///
bool X86FastISel::X86SelectAddress(const Value *V, X86AddressMode &AM) {
SmallVector<const Value *, 32> GEPs;
redo_gep:
const User *U = nullptr;
unsigned Opcode = Instruction::UserOp1;
if (const Instruction *I = dyn_cast<Instruction>(V)) {
// Don't walk into other basic blocks; it's possible we haven't
// visited them yet, so the instructions may not yet be assigned
// virtual registers.
if (FuncInfo.StaticAllocaMap.count(static_cast<const AllocaInst *>(V)) ||
FuncInfo.MBBMap[I->getParent()] == FuncInfo.MBB) {
Opcode = I->getOpcode();
U = I;
}
} else if (const ConstantExpr *C = dyn_cast<ConstantExpr>(V)) {
Opcode = C->getOpcode();
U = C;
}
if (PointerType *Ty = dyn_cast<PointerType>(V->getType()))
if (Ty->getAddressSpace() > 255)
// Fast instruction selection doesn't support the special
// address spaces.
return false;
switch (Opcode) {
default: break;
case Instruction::BitCast:
// Look past bitcasts.
return X86SelectAddress(U->getOperand(0), AM);
case Instruction::IntToPtr:
// Look past no-op inttoptrs.
if (TLI.getValueType(DL, U->getOperand(0)->getType()) ==
TLI.getPointerTy(DL))
return X86SelectAddress(U->getOperand(0), AM);
break;
case Instruction::PtrToInt:
// Look past no-op ptrtoints.
if (TLI.getValueType(DL, U->getType()) == TLI.getPointerTy(DL))
return X86SelectAddress(U->getOperand(0), AM);
break;
case Instruction::Alloca: {
// Do static allocas.
const AllocaInst *A = cast<AllocaInst>(V);
DenseMap<const AllocaInst *, int>::iterator SI =
FuncInfo.StaticAllocaMap.find(A);
if (SI != FuncInfo.StaticAllocaMap.end()) {
AM.BaseType = X86AddressMode::FrameIndexBase;
AM.Base.FrameIndex = SI->second;
return true;
}
break;
}
case Instruction::Add: {
// Adds of constants are common and easy enough.
if (const ConstantInt *CI = dyn_cast<ConstantInt>(U->getOperand(1))) {
uint64_t Disp = (int32_t)AM.Disp + (uint64_t)CI->getSExtValue();
// They have to fit in the 32-bit signed displacement field though.
if (isInt<32>(Disp)) {
AM.Disp = (uint32_t)Disp;
return X86SelectAddress(U->getOperand(0), AM);
}
}
break;
}
case Instruction::GetElementPtr: {
X86AddressMode SavedAM = AM;
// Pattern-match simple GEPs.
uint64_t Disp = (int32_t)AM.Disp;
unsigned IndexReg = AM.IndexReg;
unsigned Scale = AM.Scale;
gep_type_iterator GTI = gep_type_begin(U);
// Iterate through the indices, folding what we can. Constants can be
// folded, and one dynamic index can be handled, if the scale is supported.
for (User::const_op_iterator i = U->op_begin() + 1, e = U->op_end();
i != e; ++i, ++GTI) {
const Value *Op = *i;
if (StructType *STy = GTI.getStructTypeOrNull()) {
const StructLayout *SL = DL.getStructLayout(STy);
Disp += SL->getElementOffset(cast<ConstantInt>(Op)->getZExtValue());
continue;
}
// A array/variable index is always of the form i*S where S is the
// constant scale size. See if we can push the scale into immediates.
uint64_t S = DL.getTypeAllocSize(GTI.getIndexedType());
for (;;) {
if (const ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
// Constant-offset addressing.
Disp += CI->getSExtValue() * S;
break;
}
if (canFoldAddIntoGEP(U, Op)) {
// A compatible add with a constant operand. Fold the constant.
ConstantInt *CI =
cast<ConstantInt>(cast<AddOperator>(Op)->getOperand(1));
Disp += CI->getSExtValue() * S;
// Iterate on the other operand.
Op = cast<AddOperator>(Op)->getOperand(0);
continue;
}
if (IndexReg == 0 &&
(!AM.GV || !Subtarget->isPICStyleRIPRel()) &&
(S == 1 || S == 2 || S == 4 || S == 8)) {
// Scaled-index addressing.
Scale = S;
IndexReg = getRegForGEPIndex(Op);
if (IndexReg == 0)
return false;
break;
}
// Unsupported.
goto unsupported_gep;
}
}
// Check for displacement overflow.
if (!isInt<32>(Disp))
break;
AM.IndexReg = IndexReg;
AM.Scale = Scale;
AM.Disp = (uint32_t)Disp;
GEPs.push_back(V);
if (const GetElementPtrInst *GEP =
dyn_cast<GetElementPtrInst>(U->getOperand(0))) {
// Ok, the GEP indices were covered by constant-offset and scaled-index
// addressing. Update the address state and move on to examining the base.
V = GEP;
goto redo_gep;
} else if (X86SelectAddress(U->getOperand(0), AM)) {
return true;
}
// If we couldn't merge the gep value into this addr mode, revert back to
// our address and just match the value instead of completely failing.
AM = SavedAM;
for (const Value *I : reverse(GEPs))
if (handleConstantAddresses(I, AM))
return true;
return false;
unsupported_gep:
// Ok, the GEP indices weren't all covered.
break;
}
}
return handleConstantAddresses(V, AM);
}
/// X86SelectCallAddress - Attempt to fill in an address from the given value.
///
bool X86FastISel::X86SelectCallAddress(const Value *V, X86AddressMode &AM) {
const User *U = nullptr;
unsigned Opcode = Instruction::UserOp1;
const Instruction *I = dyn_cast<Instruction>(V);
// Record if the value is defined in the same basic block.
//
// This information is crucial to know whether or not folding an
// operand is valid.
// Indeed, FastISel generates or reuses a virtual register for all
// operands of all instructions it selects. Obviously, the definition and