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//===- ARMFastISel.cpp - ARM 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 ARM-specific support for the FastISel class. Some
// of the target-specific code is generated by tablegen in the file
// ARMGenFastISel.inc, which is #included here.
//
//===----------------------------------------------------------------------===//
#include "ARM.h"
#include "ARMBaseInstrInfo.h"
#include "ARMBaseRegisterInfo.h"
#include "ARMCallingConv.h"
#include "ARMConstantPoolValue.h"
#include "ARMISelLowering.h"
#include "ARMMachineFunctionInfo.h"
#include "ARMSubtarget.h"
#include "MCTargetDesc/ARMAddressingModes.h"
#include "MCTargetDesc/ARMBaseInfo.h"
#include "Utils/ARMBaseInfo.h"
#include "llvm/ADT/APFloat.h"
#include "llvm/ADT/APInt.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/CodeGen/CallingConvLower.h"
#include "llvm/CodeGen/FastISel.h"
#include "llvm/CodeGen/FunctionLoweringInfo.h"
#include "llvm/CodeGen/ISDOpcodes.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineMemOperand.h"
#include "llvm/CodeGen/MachineOperand.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RuntimeLibcalls.h"
#include "llvm/CodeGen/TargetInstrInfo.h"
#include "llvm/CodeGen/TargetLowering.h"
#include "llvm/CodeGen/TargetOpcodes.h"
#include "llvm/CodeGen/TargetRegisterInfo.h"
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/CodeGenTypes/MachineValueType.h"
#include "llvm/IR/Argument.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/Constant.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/GlobalValue.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/User.h"
#include "llvm/IR/Value.h"
#include "llvm/MC/MCInstrDesc.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include <cassert>
#include <cstdint>
#include <utility>
using namespace llvm;
namespace {
// All possible address modes, plus some.
struct Address {
enum {
RegBase,
FrameIndexBase
} BaseType = RegBase;
union {
unsigned Reg;
int FI;
} Base;
int Offset = 0;
// Innocuous defaults for our address.
Address() {
Base.Reg = 0;
}
};
class ARMFastISel final : public FastISel {
/// Subtarget - Keep a pointer to the ARMSubtarget around so that we can
/// make the right decision when generating code for different targets.
const ARMSubtarget *Subtarget;
Module &M;
const TargetMachine &TM;
const TargetInstrInfo &TII;
const TargetLowering &TLI;
ARMFunctionInfo *AFI;
// Convenience variables to avoid some queries.
bool isThumb2;
LLVMContext *Context;
public:
explicit ARMFastISel(FunctionLoweringInfo &funcInfo,
const TargetLibraryInfo *libInfo)
: FastISel(funcInfo, libInfo),
Subtarget(&funcInfo.MF->getSubtarget<ARMSubtarget>()),
M(const_cast<Module &>(*funcInfo.Fn->getParent())),
TM(funcInfo.MF->getTarget()), TII(*Subtarget->getInstrInfo()),
TLI(*Subtarget->getTargetLowering()) {
AFI = funcInfo.MF->getInfo<ARMFunctionInfo>();
isThumb2 = AFI->isThumbFunction();
Context = &funcInfo.Fn->getContext();
}
private:
// Code from FastISel.cpp.
unsigned fastEmitInst_r(unsigned MachineInstOpcode,
const TargetRegisterClass *RC, unsigned Op0);
unsigned fastEmitInst_rr(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, unsigned Op1);
unsigned fastEmitInst_ri(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, uint64_t Imm);
unsigned fastEmitInst_i(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
uint64_t Imm);
// Backend specific FastISel code.
bool fastSelectInstruction(const Instruction *I) override;
unsigned fastMaterializeConstant(const Constant *C) override;
unsigned fastMaterializeAlloca(const AllocaInst *AI) override;
bool tryToFoldLoadIntoMI(MachineInstr *MI, unsigned OpNo,
const LoadInst *LI) override;
bool fastLowerArguments() override;
#include "ARMGenFastISel.inc"
// Instruction selection routines.
bool SelectLoad(const Instruction *I);
bool SelectStore(const Instruction *I);
bool SelectBranch(const Instruction *I);
bool SelectIndirectBr(const Instruction *I);
bool SelectCmp(const Instruction *I);
bool SelectFPExt(const Instruction *I);
bool SelectFPTrunc(const Instruction *I);
bool SelectBinaryIntOp(const Instruction *I, unsigned ISDOpcode);
bool SelectBinaryFPOp(const Instruction *I, unsigned ISDOpcode);
bool SelectIToFP(const Instruction *I, bool isSigned);
bool SelectFPToI(const Instruction *I, bool isSigned);
bool SelectDiv(const Instruction *I, bool isSigned);
bool SelectRem(const Instruction *I, bool isSigned);
bool SelectCall(const Instruction *I, const char *IntrMemName);
bool SelectIntrinsicCall(const IntrinsicInst &I);
bool SelectSelect(const Instruction *I);
bool SelectRet(const Instruction *I);
bool SelectTrunc(const Instruction *I);
bool SelectIntExt(const Instruction *I);
bool SelectShift(const Instruction *I, ARM_AM::ShiftOpc ShiftTy);
// Utility routines.
bool isPositionIndependent() const;
bool isTypeLegal(Type *Ty, MVT &VT);
bool isLoadTypeLegal(Type *Ty, MVT &VT);
bool ARMEmitCmp(const Value *Src1Value, const Value *Src2Value,
bool isZExt);
bool ARMEmitLoad(MVT VT, Register &ResultReg, Address &Addr,
MaybeAlign Alignment = std::nullopt, bool isZExt = true,
bool allocReg = true);
bool ARMEmitStore(MVT VT, unsigned SrcReg, Address &Addr,
MaybeAlign Alignment = std::nullopt);
bool ARMComputeAddress(const Value *Obj, Address &Addr);
void ARMSimplifyAddress(Address &Addr, MVT VT, bool useAM3);
bool ARMIsMemCpySmall(uint64_t Len);
bool ARMTryEmitSmallMemCpy(Address Dest, Address Src, uint64_t Len,
MaybeAlign Alignment);
unsigned ARMEmitIntExt(MVT SrcVT, unsigned SrcReg, MVT DestVT, bool isZExt);
unsigned ARMMaterializeFP(const ConstantFP *CFP, MVT VT);
unsigned ARMMaterializeInt(const Constant *C, MVT VT);
unsigned ARMMaterializeGV(const GlobalValue *GV, MVT VT);
unsigned ARMMoveToFPReg(MVT VT, unsigned SrcReg);
unsigned ARMMoveToIntReg(MVT VT, unsigned SrcReg);
unsigned ARMSelectCallOp(bool UseReg);
unsigned ARMLowerPICELF(const GlobalValue *GV, MVT VT);
const TargetLowering *getTargetLowering() { return &TLI; }
// Call handling routines.
CCAssignFn *CCAssignFnForCall(CallingConv::ID CC,
bool Return,
bool isVarArg);
bool ProcessCallArgs(SmallVectorImpl<Value*> &Args,
SmallVectorImpl<Register> &ArgRegs,
SmallVectorImpl<MVT> &ArgVTs,
SmallVectorImpl<ISD::ArgFlagsTy> &ArgFlags,
SmallVectorImpl<Register> &RegArgs,
CallingConv::ID CC,
unsigned &NumBytes,
bool isVarArg);
unsigned getLibcallReg(const Twine &Name);
bool FinishCall(MVT RetVT, SmallVectorImpl<Register> &UsedRegs,
const Instruction *I, CallingConv::ID CC,
unsigned &NumBytes, bool isVarArg);
bool ARMEmitLibcall(const Instruction *I, RTLIB::Libcall Call);
// OptionalDef handling routines.
bool isARMNEONPred(const MachineInstr *MI);
bool DefinesOptionalPredicate(MachineInstr *MI, bool *CPSR);
const MachineInstrBuilder &AddOptionalDefs(const MachineInstrBuilder &MIB);
void AddLoadStoreOperands(MVT VT, Address &Addr,
const MachineInstrBuilder &MIB,
MachineMemOperand::Flags Flags, bool useAM3);
};
} // end anonymous namespace
// DefinesOptionalPredicate - This is different from DefinesPredicate in that
// we don't care about implicit defs here, just places we'll need to add a
// default CCReg argument. Sets CPSR if we're setting CPSR instead of CCR.
bool ARMFastISel::DefinesOptionalPredicate(MachineInstr *MI, bool *CPSR) {
if (!MI->hasOptionalDef())
return false;
// Look to see if our OptionalDef is defining CPSR or CCR.
for (const MachineOperand &MO : MI->operands()) {
if (!MO.isReg() || !MO.isDef()) continue;
if (MO.getReg() == ARM::CPSR)
*CPSR = true;
}
return true;
}
bool ARMFastISel::isARMNEONPred(const MachineInstr *MI) {
const MCInstrDesc &MCID = MI->getDesc();
// If we're a thumb2 or not NEON function we'll be handled via isPredicable.
if ((MCID.TSFlags & ARMII::DomainMask) != ARMII::DomainNEON ||
AFI->isThumb2Function())
return MI->isPredicable();
for (const MCOperandInfo &opInfo : MCID.operands())
if (opInfo.isPredicate())
return true;
return false;
}
// If the machine is predicable go ahead and add the predicate operands, if
// it needs default CC operands add those.
// TODO: If we want to support thumb1 then we'll need to deal with optional
// CPSR defs that need to be added before the remaining operands. See s_cc_out
// for descriptions why.
const MachineInstrBuilder &
ARMFastISel::AddOptionalDefs(const MachineInstrBuilder &MIB) {
MachineInstr *MI = &*MIB;
// Do we use a predicate? or...
// Are we NEON in ARM mode and have a predicate operand? If so, I know
// we're not predicable but add it anyways.
if (isARMNEONPred(MI))
MIB.add(predOps(ARMCC::AL));
// Do we optionally set a predicate? Preds is size > 0 iff the predicate
// defines CPSR. All other OptionalDefines in ARM are the CCR register.
bool CPSR = false;
if (DefinesOptionalPredicate(MI, &CPSR))
MIB.add(CPSR ? t1CondCodeOp() : condCodeOp());
return MIB;
}
unsigned ARMFastISel::fastEmitInst_r(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0) {
Register ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
// Make sure the input operand is sufficiently constrained to be legal
// for this instruction.
Op0 = constrainOperandRegClass(II, Op0, 1);
if (II.getNumDefs() >= 1) {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, II,
ResultReg).addReg(Op0));
} else {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, II)
.addReg(Op0));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(TargetOpcode::COPY), ResultReg)
.addReg(II.implicit_defs()[0]));
}
return ResultReg;
}
unsigned ARMFastISel::fastEmitInst_rr(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, unsigned Op1) {
Register ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
// Make sure the input operands are sufficiently constrained to be legal
// for this instruction.
Op0 = constrainOperandRegClass(II, Op0, 1);
Op1 = constrainOperandRegClass(II, Op1, 2);
if (II.getNumDefs() >= 1) {
AddOptionalDefs(
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, II, ResultReg)
.addReg(Op0)
.addReg(Op1));
} else {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, II)
.addReg(Op0)
.addReg(Op1));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(TargetOpcode::COPY), ResultReg)
.addReg(II.implicit_defs()[0]));
}
return ResultReg;
}
unsigned ARMFastISel::fastEmitInst_ri(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, uint64_t Imm) {
Register ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
// Make sure the input operand is sufficiently constrained to be legal
// for this instruction.
Op0 = constrainOperandRegClass(II, Op0, 1);
if (II.getNumDefs() >= 1) {
AddOptionalDefs(
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, II, ResultReg)
.addReg(Op0)
.addImm(Imm));
} else {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, II)
.addReg(Op0)
.addImm(Imm));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(TargetOpcode::COPY), ResultReg)
.addReg(II.implicit_defs()[0]));
}
return ResultReg;
}
unsigned ARMFastISel::fastEmitInst_i(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
uint64_t Imm) {
Register ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
if (II.getNumDefs() >= 1) {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, II,
ResultReg).addImm(Imm));
} else {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, II)
.addImm(Imm));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(TargetOpcode::COPY), ResultReg)
.addReg(II.implicit_defs()[0]));
}
return ResultReg;
}
// TODO: Don't worry about 64-bit now, but when this is fixed remove the
// checks from the various callers.
unsigned ARMFastISel::ARMMoveToFPReg(MVT VT, unsigned SrcReg) {
if (VT == MVT::f64) return 0;
Register MoveReg = createResultReg(TLI.getRegClassFor(VT));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::VMOVSR), MoveReg)
.addReg(SrcReg));
return MoveReg;
}
unsigned ARMFastISel::ARMMoveToIntReg(MVT VT, unsigned SrcReg) {
if (VT == MVT::i64) return 0;
Register MoveReg = createResultReg(TLI.getRegClassFor(VT));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::VMOVRS), MoveReg)
.addReg(SrcReg));
return MoveReg;
}
// For double width floating point we need to materialize two constants
// (the high and the low) into integer registers then use a move to get
// the combined constant into an FP reg.
unsigned ARMFastISel::ARMMaterializeFP(const ConstantFP *CFP, MVT VT) {
const APFloat Val = CFP->getValueAPF();
bool is64bit = VT == MVT::f64;
// This checks to see if we can use VFP3 instructions to materialize
// a constant, otherwise we have to go through the constant pool.
if (TLI.isFPImmLegal(Val, VT)) {
int Imm;
unsigned Opc;
if (is64bit) {
Imm = ARM_AM::getFP64Imm(Val);
Opc = ARM::FCONSTD;
} else {
Imm = ARM_AM::getFP32Imm(Val);
Opc = ARM::FCONSTS;
}
Register DestReg = createResultReg(TLI.getRegClassFor(VT));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), DestReg).addImm(Imm));
return DestReg;
}
// Require VFP2 for loading fp constants.
if (!Subtarget->hasVFP2Base()) return false;
// MachineConstantPool wants an explicit alignment.
Align Alignment = DL.getPrefTypeAlign(CFP->getType());
unsigned Idx = MCP.getConstantPoolIndex(cast<Constant>(CFP), Alignment);
Register DestReg = createResultReg(TLI.getRegClassFor(VT));
unsigned Opc = is64bit ? ARM::VLDRD : ARM::VLDRS;
// The extra reg is for addrmode5.
AddOptionalDefs(
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(Opc), DestReg)
.addConstantPoolIndex(Idx)
.addReg(0));
return DestReg;
}
unsigned ARMFastISel::ARMMaterializeInt(const Constant *C, MVT VT) {
if (VT != MVT::i32 && VT != MVT::i16 && VT != MVT::i8 && VT != MVT::i1)
return 0;
// If we can do this in a single instruction without a constant pool entry
// do so now.
const ConstantInt *CI = cast<ConstantInt>(C);
if (Subtarget->hasV6T2Ops() && isUInt<16>(CI->getZExtValue())) {
unsigned Opc = isThumb2 ? ARM::t2MOVi16 : ARM::MOVi16;
const TargetRegisterClass *RC = isThumb2 ? &ARM::rGPRRegClass :
&ARM::GPRRegClass;
Register ImmReg = createResultReg(RC);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), ImmReg)
.addImm(CI->getZExtValue()));
return ImmReg;
}
// Use MVN to emit negative constants.
if (VT == MVT::i32 && Subtarget->hasV6T2Ops() && CI->isNegative()) {
unsigned Imm = (unsigned)~(CI->getSExtValue());
bool UseImm = isThumb2 ? (ARM_AM::getT2SOImmVal(Imm) != -1) :
(ARM_AM::getSOImmVal(Imm) != -1);
if (UseImm) {
unsigned Opc = isThumb2 ? ARM::t2MVNi : ARM::MVNi;
const TargetRegisterClass *RC = isThumb2 ? &ARM::rGPRRegClass :
&ARM::GPRRegClass;
Register ImmReg = createResultReg(RC);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), ImmReg)
.addImm(Imm));
return ImmReg;
}
}
unsigned ResultReg = 0;
if (Subtarget->useMovt())
ResultReg = fastEmit_i(VT, VT, ISD::Constant, CI->getZExtValue());
if (ResultReg)
return ResultReg;
// Load from constant pool. For now 32-bit only.
if (VT != MVT::i32)
return 0;
// MachineConstantPool wants an explicit alignment.
Align Alignment = DL.getPrefTypeAlign(C->getType());
unsigned Idx = MCP.getConstantPoolIndex(C, Alignment);
ResultReg = createResultReg(TLI.getRegClassFor(VT));
if (isThumb2)
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::t2LDRpci), ResultReg)
.addConstantPoolIndex(Idx));
else {
// The extra immediate is for addrmode2.
ResultReg = constrainOperandRegClass(TII.get(ARM::LDRcp), ResultReg, 0);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::LDRcp), ResultReg)
.addConstantPoolIndex(Idx)
.addImm(0));
}
return ResultReg;
}
bool ARMFastISel::isPositionIndependent() const {
return TLI.isPositionIndependent();
}
unsigned ARMFastISel::ARMMaterializeGV(const GlobalValue *GV, MVT VT) {
// For now 32-bit only.
if (VT != MVT::i32 || GV->isThreadLocal()) return 0;
// ROPI/RWPI not currently supported.
if (Subtarget->isROPI() || Subtarget->isRWPI())
return 0;
bool IsIndirect = Subtarget->isGVIndirectSymbol(GV);
const TargetRegisterClass *RC = isThumb2 ? &ARM::rGPRRegClass
: &ARM::GPRRegClass;
Register DestReg = createResultReg(RC);
// FastISel TLS support on non-MachO is broken, punt to SelectionDAG.
const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
bool IsThreadLocal = GVar && GVar->isThreadLocal();
if (!Subtarget->isTargetMachO() && IsThreadLocal) return 0;
bool IsPositionIndependent = isPositionIndependent();
// Use movw+movt when possible, it avoids constant pool entries.
// Non-darwin targets only support static movt relocations in FastISel.
if (Subtarget->useMovt() &&
(Subtarget->isTargetMachO() || !IsPositionIndependent)) {
unsigned Opc;
unsigned char TF = 0;
if (Subtarget->isTargetMachO())
TF = ARMII::MO_NONLAZY;
if (IsPositionIndependent)
Opc = isThumb2 ? ARM::t2MOV_ga_pcrel : ARM::MOV_ga_pcrel;
else
Opc = isThumb2 ? ARM::t2MOVi32imm : ARM::MOVi32imm;
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), DestReg).addGlobalAddress(GV, 0, TF));
} else {
// MachineConstantPool wants an explicit alignment.
Align Alignment = DL.getPrefTypeAlign(GV->getType());
if (Subtarget->isTargetELF() && IsPositionIndependent)
return ARMLowerPICELF(GV, VT);
// Grab index.
unsigned PCAdj = IsPositionIndependent ? (Subtarget->isThumb() ? 4 : 8) : 0;
unsigned Id = AFI->createPICLabelUId();
ARMConstantPoolValue *CPV = ARMConstantPoolConstant::Create(GV, Id,
ARMCP::CPValue,
PCAdj);
unsigned Idx = MCP.getConstantPoolIndex(CPV, Alignment);
// Load value.
MachineInstrBuilder MIB;
if (isThumb2) {
unsigned Opc = IsPositionIndependent ? ARM::t2LDRpci_pic : ARM::t2LDRpci;
MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(Opc),
DestReg).addConstantPoolIndex(Idx);
if (IsPositionIndependent)
MIB.addImm(Id);
AddOptionalDefs(MIB);
} else {
// The extra immediate is for addrmode2.
DestReg = constrainOperandRegClass(TII.get(ARM::LDRcp), DestReg, 0);
MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::LDRcp), DestReg)
.addConstantPoolIndex(Idx)
.addImm(0);
AddOptionalDefs(MIB);
if (IsPositionIndependent) {
unsigned Opc = IsIndirect ? ARM::PICLDR : ARM::PICADD;
Register NewDestReg = createResultReg(TLI.getRegClassFor(VT));
MachineInstrBuilder MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt,
MIMD, TII.get(Opc), NewDestReg)
.addReg(DestReg)
.addImm(Id);
AddOptionalDefs(MIB);
return NewDestReg;
}
}
}
if ((Subtarget->isTargetELF() && Subtarget->isGVInGOT(GV)) ||
(Subtarget->isTargetMachO() && IsIndirect)) {
MachineInstrBuilder MIB;
Register NewDestReg = createResultReg(TLI.getRegClassFor(VT));
if (isThumb2)
MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::t2LDRi12), NewDestReg)
.addReg(DestReg)
.addImm(0);
else
MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::LDRi12), NewDestReg)
.addReg(DestReg)
.addImm(0);
DestReg = NewDestReg;
AddOptionalDefs(MIB);
}
return DestReg;
}
unsigned ARMFastISel::fastMaterializeConstant(const Constant *C) {
EVT CEVT = TLI.getValueType(DL, C->getType(), true);
// Only handle simple types.
if (!CEVT.isSimple()) return 0;
MVT VT = CEVT.getSimpleVT();
if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C))
return ARMMaterializeFP(CFP, VT);
else if (const GlobalValue *GV = dyn_cast<GlobalValue>(C))
return ARMMaterializeGV(GV, VT);
else if (isa<ConstantInt>(C))
return ARMMaterializeInt(C, VT);
return 0;
}
// TODO: unsigned ARMFastISel::TargetMaterializeFloatZero(const ConstantFP *CF);
unsigned ARMFastISel::fastMaterializeAlloca(const AllocaInst *AI) {
// Don't handle dynamic allocas.
if (!FuncInfo.StaticAllocaMap.count(AI)) return 0;
MVT VT;
if (!isLoadTypeLegal(AI->getType(), VT)) return 0;
DenseMap<const AllocaInst*, int>::iterator SI =
FuncInfo.StaticAllocaMap.find(AI);
// This will get lowered later into the correct offsets and registers
// via rewriteXFrameIndex.
if (SI != FuncInfo.StaticAllocaMap.end()) {
unsigned Opc = isThumb2 ? ARM::t2ADDri : ARM::ADDri;
const TargetRegisterClass* RC = TLI.getRegClassFor(VT);
Register ResultReg = createResultReg(RC);
ResultReg = constrainOperandRegClass(TII.get(Opc), ResultReg, 0);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), ResultReg)
.addFrameIndex(SI->second)
.addImm(0));
return ResultReg;
}
return 0;
}
bool ARMFastISel::isTypeLegal(Type *Ty, MVT &VT) {
EVT evt = TLI.getValueType(DL, Ty, true);
// Only handle simple types.
if (evt == MVT::Other || !evt.isSimple()) return false;
VT = evt.getSimpleVT();
// Handle all legal types, i.e. a register that will directly hold this
// value.
return TLI.isTypeLegal(VT);
}
bool ARMFastISel::isLoadTypeLegal(Type *Ty, MVT &VT) {
if (isTypeLegal(Ty, VT)) return true;
// If this is a type than can be sign or zero-extended to a basic operation
// go ahead and accept it now.
if (VT == MVT::i1 || VT == MVT::i8 || VT == MVT::i16)
return true;
return false;
}
// Computes the address to get to an object.
bool ARMFastISel::ARMComputeAddress(const Value *Obj, Address &Addr) {
// Some boilerplate from the X86 FastISel.
const User *U = nullptr;
unsigned Opcode = Instruction::UserOp1;
if (const Instruction *I = dyn_cast<Instruction>(Obj)) {
// Don't walk into other basic blocks unless the object is an alloca from
// another block, otherwise it may not have a virtual register assigned.
if (FuncInfo.StaticAllocaMap.count(static_cast<const AllocaInst *>(Obj)) ||
FuncInfo.MBBMap[I->getParent()] == FuncInfo.MBB) {
Opcode = I->getOpcode();
U = I;
}
} else if (const ConstantExpr *C = dyn_cast<ConstantExpr>(Obj)) {
Opcode = C->getOpcode();
U = C;
}
if (PointerType *Ty = dyn_cast<PointerType>(Obj->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 through bitcasts.
return ARMComputeAddress(U->getOperand(0), Addr);
case Instruction::IntToPtr:
// Look past no-op inttoptrs.
if (TLI.getValueType(DL, U->getOperand(0)->getType()) ==
TLI.getPointerTy(DL))
return ARMComputeAddress(U->getOperand(0), Addr);
break;
case Instruction::PtrToInt:
// Look past no-op ptrtoints.
if (TLI.getValueType(DL, U->getType()) == TLI.getPointerTy(DL))
return ARMComputeAddress(U->getOperand(0), Addr);
break;
case Instruction::GetElementPtr: {
Address SavedAddr = Addr;
int TmpOffset = Addr.Offset;
// Iterate through the GEP folding the constants into offsets where
// we can.
gep_type_iterator GTI = gep_type_begin(U);
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);
unsigned Idx = cast<ConstantInt>(Op)->getZExtValue();
TmpOffset += SL->getElementOffset(Idx);
} else {
uint64_t S = GTI.getSequentialElementStride(DL);
while (true) {
if (const ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
// Constant-offset addressing.
TmpOffset += 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));
TmpOffset += CI->getSExtValue() * S;
// Iterate on the other operand.
Op = cast<AddOperator>(Op)->getOperand(0);
continue;
}
// Unsupported
goto unsupported_gep;
}
}
}
// Try to grab the base operand now.
Addr.Offset = TmpOffset;
if (ARMComputeAddress(U->getOperand(0), Addr)) return true;
// We failed, restore everything and try the other options.
Addr = SavedAddr;
unsupported_gep:
break;
}
case Instruction::Alloca: {
const AllocaInst *AI = cast<AllocaInst>(Obj);
DenseMap<const AllocaInst*, int>::iterator SI =
FuncInfo.StaticAllocaMap.find(AI);
if (SI != FuncInfo.StaticAllocaMap.end()) {
Addr.BaseType = Address::FrameIndexBase;
Addr.Base.FI = SI->second;
return true;
}
break;
}
}
// Try to get this in a register if nothing else has worked.
if (Addr.Base.Reg == 0) Addr.Base.Reg = getRegForValue(Obj);
return Addr.Base.Reg != 0;
}
void ARMFastISel::ARMSimplifyAddress(Address &Addr, MVT VT, bool useAM3) {
bool needsLowering = false;
switch (VT.SimpleTy) {
default: llvm_unreachable("Unhandled load/store type!");
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
if (!useAM3) {
// Integer loads/stores handle 12-bit offsets.
needsLowering = ((Addr.Offset & 0xfff) != Addr.Offset);
// Handle negative offsets.
if (needsLowering && isThumb2)
needsLowering = !(Subtarget->hasV6T2Ops() && Addr.Offset < 0 &&
Addr.Offset > -256);
} else {
// ARM halfword load/stores and signed byte loads use +/-imm8 offsets.
needsLowering = (Addr.Offset > 255 || Addr.Offset < -255);
}
break;
case MVT::f32:
case MVT::f64:
// Floating point operands handle 8-bit offsets.
needsLowering = ((Addr.Offset & 0xff) != Addr.Offset);
break;
}
// If this is a stack pointer and the offset needs to be simplified then
// put the alloca address into a register, set the base type back to
// register and continue. This should almost never happen.
if (needsLowering && Addr.BaseType == Address::FrameIndexBase) {
const TargetRegisterClass *RC = isThumb2 ? &ARM::tGPRRegClass
: &ARM::GPRRegClass;
Register ResultReg = createResultReg(RC);
unsigned Opc = isThumb2 ? ARM::t2ADDri : ARM::ADDri;
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), ResultReg)
.addFrameIndex(Addr.Base.FI)
.addImm(0));
Addr.Base.Reg = ResultReg;
Addr.BaseType = Address::RegBase;
}
// Since the offset is too large for the load/store instruction
// get the reg+offset into a register.
if (needsLowering) {
Addr.Base.Reg = fastEmit_ri_(MVT::i32, ISD::ADD, Addr.Base.Reg,
Addr.Offset, MVT::i32);
Addr.Offset = 0;
}
}
void ARMFastISel::AddLoadStoreOperands(MVT VT, Address &Addr,
const MachineInstrBuilder &MIB,
MachineMemOperand::Flags Flags,
bool useAM3) {
// addrmode5 output depends on the selection dag addressing dividing the
// offset by 4 that it then later multiplies. Do this here as well.
if (VT.SimpleTy == MVT::f32 || VT.SimpleTy == MVT::f64)
Addr.Offset /= 4;
// Frame base works a bit differently. Handle it separately.
if (Addr.BaseType == Address::FrameIndexBase) {
int FI = Addr.Base.FI;
int Offset = Addr.Offset;
MachineMemOperand *MMO = FuncInfo.MF->getMachineMemOperand(
MachinePointerInfo::getFixedStack(*FuncInfo.MF, FI, Offset), Flags,
MFI.getObjectSize(FI), MFI.getObjectAlign(FI));
// Now add the rest of the operands.
MIB.addFrameIndex(FI);
// ARM halfword load/stores and signed byte loads need an additional
// operand.
if (useAM3) {
int Imm = (Addr.Offset < 0) ? (0x100 | -Addr.Offset) : Addr.Offset;
MIB.addReg(0);
MIB.addImm(Imm);
} else {
MIB.addImm(Addr.Offset);
}
MIB.addMemOperand(MMO);
} else {
// Now add the rest of the operands.
MIB.addReg(Addr.Base.Reg);
// ARM halfword load/stores and signed byte loads need an additional
// operand.
if (useAM3) {
int Imm = (Addr.Offset < 0) ? (0x100 | -Addr.Offset) : Addr.Offset;
MIB.addReg(0);
MIB.addImm(Imm);
} else {
MIB.addImm(Addr.Offset);
}
}
AddOptionalDefs(MIB);
}
bool ARMFastISel::ARMEmitLoad(MVT VT, Register &ResultReg, Address &Addr,
MaybeAlign Alignment, bool isZExt,
bool allocReg) {
unsigned Opc;
bool useAM3 = false;
bool needVMOV = false;
const TargetRegisterClass *RC;
switch (VT.SimpleTy) {
// This is mostly going to be Neon/vector support.
default: return false;
case MVT::i1:
case MVT::i8:
if (isThumb2) {
if (Addr.Offset < 0 && Addr.Offset > -256 && Subtarget->hasV6T2Ops())
Opc = isZExt ? ARM::t2LDRBi8 : ARM::t2LDRSBi8;
else
Opc = isZExt ? ARM::t2LDRBi12 : ARM::t2LDRSBi12;
} else {
if (isZExt) {
Opc = ARM::LDRBi12;
} else {
Opc = ARM::LDRSB;
useAM3 = true;
}
}
RC = isThumb2 ? &ARM::rGPRRegClass : &ARM::GPRnopcRegClass;
break;
case MVT::i16:
if (Alignment && *Alignment < Align(2) &&
!Subtarget->allowsUnalignedMem())
return false;
if (isThumb2) {
if (Addr.Offset < 0 && Addr.Offset > -256 && Subtarget->hasV6T2Ops())
Opc = isZExt ? ARM::t2LDRHi8 : ARM::t2LDRSHi8;
else
Opc = isZExt ? ARM::t2LDRHi12 : ARM::t2LDRSHi12;
} else {
Opc = isZExt ? ARM::LDRH : ARM::LDRSH;
useAM3 = true;
}
RC = isThumb2 ? &ARM::rGPRRegClass : &ARM::GPRnopcRegClass;
break;
case MVT::i32:
if (Alignment && *Alignment < Align(4) &&
!Subtarget->allowsUnalignedMem())
return false;
if (isThumb2) {
if (Addr.Offset < 0 && Addr.Offset > -256 && Subtarget->hasV6T2Ops())
Opc = ARM::t2LDRi8;
else
Opc = ARM::t2LDRi12;
} else {
Opc = ARM::LDRi12;
}
RC = isThumb2 ? &ARM::rGPRRegClass : &ARM::GPRnopcRegClass;
break;
case MVT::f32:
if (!Subtarget->hasVFP2Base()) return false;
// Unaligned loads need special handling. Floats require word-alignment.
if (Alignment && *Alignment < Align(4)) {
needVMOV = true;
VT = MVT::i32;
Opc = isThumb2 ? ARM::t2LDRi12 : ARM::LDRi12;
RC = isThumb2 ? &ARM::rGPRRegClass : &ARM::GPRnopcRegClass;
} else {
Opc = ARM::VLDRS;
RC = TLI.getRegClassFor(VT);
}
break;
case MVT::f64:
// Can load and store double precision even without FeatureFP64
if (!Subtarget->hasVFP2Base()) return false;
// FIXME: Unaligned loads need special handling. Doublewords require
// word-alignment.
if (Alignment && *Alignment < Align(4))
return false;
Opc = ARM::VLDRD;
RC = TLI.getRegClassFor(VT);
break;
}
// Simplify this down to something we can handle.
ARMSimplifyAddress(Addr, VT, useAM3);
// Create the base instruction, then add the operands.
if (allocReg)
ResultReg = createResultReg(RC);
assert(ResultReg > 255 && "Expected an allocated virtual register.");
MachineInstrBuilder MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), ResultReg);
AddLoadStoreOperands(VT, Addr, MIB, MachineMemOperand::MOLoad, useAM3);
// If we had an unaligned load of a float we've converted it to an regular
// load. Now we must move from the GRP to the FP register.
if (needVMOV) {
Register MoveReg = createResultReg(TLI.getRegClassFor(MVT::f32));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::VMOVSR), MoveReg)
.addReg(ResultReg));
ResultReg = MoveReg;
}
return true;
}
bool ARMFastISel::SelectLoad(const Instruction *I) {
// Atomic loads need special handling.
if (cast<LoadInst>(I)->isAtomic())
return false;
const Value *SV = I->getOperand(0);
if (TLI.supportSwiftError()) {
// Swifterror values can come from either a function parameter with
// swifterror attribute or an alloca with swifterror attribute.
if (const Argument *Arg = dyn_cast<Argument>(SV)) {
if (Arg->hasSwiftErrorAttr())
return false;
}
if (const AllocaInst *Alloca = dyn_cast<AllocaInst>(SV)) {
if (Alloca->isSwiftError())
return false;
}
}
// Verify we have a legal type before going any further.
MVT VT;
if (!isLoadTypeLegal(I->getType(), VT))
return false;
// See if we can handle this address.
Address Addr;
if (!ARMComputeAddress(I->getOperand(0), Addr)) return false;
Register ResultReg;
if (!ARMEmitLoad(VT, ResultReg, Addr, cast<LoadInst>(I)->getAlign()))
return false;
updateValueMap(I, ResultReg);
return true;
}
bool ARMFastISel::ARMEmitStore(MVT VT, unsigned SrcReg, Address &Addr,
MaybeAlign Alignment) {
unsigned StrOpc;
bool useAM3 = false;
switch (VT.SimpleTy) {
// This is mostly going to be Neon/vector support.
default: return false;
case MVT::i1: {
Register Res = createResultReg(isThumb2 ? &ARM::tGPRRegClass
: &ARM::GPRRegClass);
unsigned Opc = isThumb2 ? ARM::t2ANDri : ARM::ANDri;
SrcReg = constrainOperandRegClass(TII.get(Opc), SrcReg, 1);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), Res)
.addReg(SrcReg).addImm(1));
SrcReg = Res;
[[fallthrough]];
}
case MVT::i8:
if (isThumb2) {
if (Addr.Offset < 0 && Addr.Offset > -256 && Subtarget->hasV6T2Ops())
StrOpc = ARM::t2STRBi8;
else
StrOpc = ARM::t2STRBi12;
} else {
StrOpc = ARM::STRBi12;
}
break;
case MVT::i16:
if (Alignment && *Alignment < Align(2) &&
!Subtarget->allowsUnalignedMem())
return false;
if (isThumb2) {
if (Addr.Offset < 0 && Addr.Offset > -256 && Subtarget->hasV6T2Ops())
StrOpc = ARM::t2STRHi8;
else
StrOpc = ARM::t2STRHi12;
} else {
StrOpc = ARM::STRH;
useAM3 = true;
}
break;
case MVT::i32:
if (Alignment && *Alignment < Align(4) &&
!Subtarget->allowsUnalignedMem())
return false;
if (isThumb2) {
if (Addr.Offset < 0 && Addr.Offset > -256 && Subtarget->hasV6T2Ops())
StrOpc = ARM::t2STRi8;
else
StrOpc = ARM::t2STRi12;
} else {
StrOpc = ARM::STRi12;
}
break;
case MVT::f32:
if (!Subtarget->hasVFP2Base()) return false;
// Unaligned stores need special handling. Floats require word-alignment.
if (Alignment && *Alignment < Align(4)) {
Register MoveReg = createResultReg(TLI.getRegClassFor(MVT::i32));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::VMOVRS), MoveReg)
.addReg(SrcReg));
SrcReg = MoveReg;
VT = MVT::i32;
StrOpc = isThumb2 ? ARM::t2STRi12 : ARM::STRi12;
} else {
StrOpc = ARM::VSTRS;
}
break;
case MVT::f64:
// Can load and store double precision even without FeatureFP64
if (!Subtarget->hasVFP2Base()) return false;
// FIXME: Unaligned stores need special handling. Doublewords require
// word-alignment.
if (Alignment && *Alignment < Align(4))
return false;
StrOpc = ARM::VSTRD;
break;
}
// Simplify this down to something we can handle.
ARMSimplifyAddress(Addr, VT, useAM3);
// Create the base instruction, then add the operands.
SrcReg = constrainOperandRegClass(TII.get(StrOpc), SrcReg, 0);
MachineInstrBuilder MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(StrOpc))
.addReg(SrcReg);
AddLoadStoreOperands(VT, Addr, MIB, MachineMemOperand::MOStore, useAM3);
return true;
}
bool ARMFastISel::SelectStore(const Instruction *I) {
Value *Op0 = I->getOperand(0);
unsigned SrcReg = 0;
// Atomic stores need special handling.
if (cast<StoreInst>(I)->isAtomic())
return false;
const Value *PtrV = I->getOperand(1);
if (TLI.supportSwiftError()) {
// Swifterror values can come from either a function parameter with
// swifterror attribute or an alloca with swifterror attribute.
if (const Argument *Arg = dyn_cast<Argument>(PtrV)) {
if (Arg->hasSwiftErrorAttr())
return false;
}
if (const AllocaInst *Alloca = dyn_cast<AllocaInst>(PtrV)) {
if (Alloca->isSwiftError())
return false;
}
}
// Verify we have a legal type before going any further.
MVT VT;
if (!isLoadTypeLegal(I->getOperand(0)->getType(), VT))
return false;
// Get the value to be stored into a register.
SrcReg = getRegForValue(Op0);
if (SrcReg == 0) return false;
// See if we can handle this address.
Address Addr;
if (!ARMComputeAddress(I->getOperand(1), Addr))
return false;
if (!ARMEmitStore(VT, SrcReg, Addr, cast<StoreInst>(I)->getAlign()))
return false;
return true;
}
static ARMCC::CondCodes getComparePred(CmpInst::Predicate Pred) {
switch (Pred) {
// Needs two compares...
case CmpInst::FCMP_ONE:
case CmpInst::FCMP_UEQ:
default:
// AL is our "false" for now. The other two need more compares.
return ARMCC::AL;
case CmpInst::ICMP_EQ:
case CmpInst::FCMP_OEQ:
return ARMCC::EQ;
case CmpInst::ICMP_SGT:
case CmpInst::FCMP_OGT:
return ARMCC::GT;
case CmpInst::ICMP_SGE:
case CmpInst::FCMP_OGE:
return ARMCC::GE;
case CmpInst::ICMP_UGT:
case CmpInst::FCMP_UGT:
return ARMCC::HI;
case CmpInst::FCMP_OLT:
return ARMCC::MI;
case CmpInst::ICMP_ULE:
case CmpInst::FCMP_OLE:
return ARMCC::LS;
case CmpInst::FCMP_ORD:
return ARMCC::VC;
case CmpInst::FCMP_UNO:
return ARMCC::VS;
case CmpInst::FCMP_UGE:
return ARMCC::PL;
case CmpInst::ICMP_SLT:
case CmpInst::FCMP_ULT:
return ARMCC::LT;
case CmpInst::ICMP_SLE:
case CmpInst::FCMP_ULE:
return ARMCC::LE;
case CmpInst::FCMP_UNE:
case CmpInst::ICMP_NE:
return ARMCC::NE;
case CmpInst::ICMP_UGE:
return ARMCC::HS;
case CmpInst::ICMP_ULT:
return ARMCC::LO;
}
}
bool ARMFastISel::SelectBranch(const Instruction *I) {
const BranchInst *BI = cast<BranchInst>(I);
MachineBasicBlock *TBB = FuncInfo.MBBMap[BI->getSuccessor(0)];
MachineBasicBlock *FBB = FuncInfo.MBBMap[BI->getSuccessor(1)];
// Simple branch support.
// If we can, avoid recomputing the compare - redoing it could lead to wonky
// behavior.
if (const CmpInst *CI = dyn_cast<CmpInst>(BI->getCondition())) {
if (CI->hasOneUse() && (CI->getParent() == I->getParent())) {
// Get the compare predicate.
// Try to take advantage of fallthrough opportunities.
CmpInst::Predicate Predicate = CI->getPredicate();
if (FuncInfo.MBB->isLayoutSuccessor(TBB)) {
std::swap(TBB, FBB);
Predicate = CmpInst::getInversePredicate(Predicate);
}
ARMCC::CondCodes ARMPred = getComparePred(Predicate);
// We may not handle every CC for now.
if (ARMPred == ARMCC::AL) return false;
// Emit the compare.
if (!ARMEmitCmp(CI->getOperand(0), CI->getOperand(1), CI->isUnsigned()))
return false;
unsigned BrOpc = isThumb2 ? ARM::t2Bcc : ARM::Bcc;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(BrOpc))
.addMBB(TBB).addImm(ARMPred).addReg(ARM::CPSR);
finishCondBranch(BI->getParent(), TBB, FBB);
return true;
}
} else if (TruncInst *TI = dyn_cast<TruncInst>(BI->getCondition())) {
MVT SourceVT;
if (TI->hasOneUse() && TI->getParent() == I->getParent() &&
(isLoadTypeLegal(TI->getOperand(0)->getType(), SourceVT))) {
unsigned TstOpc = isThumb2 ? ARM::t2TSTri : ARM::TSTri;
Register OpReg = getRegForValue(TI->getOperand(0));
OpReg = constrainOperandRegClass(TII.get(TstOpc), OpReg, 0);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(TstOpc))
.addReg(OpReg).addImm(1));
unsigned CCMode = ARMCC::NE;
if (FuncInfo.MBB->isLayoutSuccessor(TBB)) {
std::swap(TBB, FBB);
CCMode = ARMCC::EQ;
}
unsigned BrOpc = isThumb2 ? ARM::t2Bcc : ARM::Bcc;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(BrOpc))
.addMBB(TBB).addImm(CCMode).addReg(ARM::CPSR);
finishCondBranch(BI->getParent(), TBB, FBB);
return true;
}
} else if (const ConstantInt *CI =
dyn_cast<ConstantInt>(BI->getCondition())) {
uint64_t Imm = CI->getZExtValue();
MachineBasicBlock *Target = (Imm == 0) ? FBB : TBB;
fastEmitBranch(Target, MIMD.getDL());
return true;
}
Register CmpReg = getRegForValue(BI->getCondition());
if (CmpReg == 0) return false;
// We've been divorced from our compare! Our block was split, and
// now our compare lives in a predecessor block. We musn't
// re-compare here, as the children of the compare aren't guaranteed
// live across the block boundary (we *could* check for this).
// Regardless, the compare has been done in the predecessor block,
// and it left a value for us in a virtual register. Ergo, we test
// the one-bit value left in the virtual register.
unsigned TstOpc = isThumb2 ? ARM::t2TSTri : ARM::TSTri;
CmpReg = constrainOperandRegClass(TII.get(TstOpc), CmpReg, 0);
AddOptionalDefs(
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(TstOpc))
.addReg(CmpReg)
.addImm(1));
unsigned CCMode = ARMCC::NE;
if (FuncInfo.MBB->isLayoutSuccessor(TBB)) {
std::swap(TBB, FBB);
CCMode = ARMCC::EQ;
}
unsigned BrOpc = isThumb2 ? ARM::t2Bcc : ARM::Bcc;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(BrOpc))
.addMBB(TBB).addImm(CCMode).addReg(ARM::CPSR);
finishCondBranch(BI->getParent(), TBB, FBB);
return true;
}
bool ARMFastISel::SelectIndirectBr(const Instruction *I) {
Register AddrReg = getRegForValue(I->getOperand(0));
if (AddrReg == 0) return false;
unsigned Opc = isThumb2 ? ARM::tBRIND : ARM::BX;
assert(isThumb2 || Subtarget->hasV4TOps());
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc)).addReg(AddrReg));
const IndirectBrInst *IB = cast<IndirectBrInst>(I);
for (const BasicBlock *SuccBB : IB->successors())
FuncInfo.MBB->addSuccessor(FuncInfo.MBBMap[SuccBB]);
return true;
}
bool ARMFastISel::ARMEmitCmp(const Value *Src1Value, const Value *Src2Value,
bool isZExt) {
Type *Ty = Src1Value->getType();
EVT SrcEVT = TLI.getValueType(DL, Ty, true);
if (!SrcEVT.isSimple()) return false;
MVT SrcVT = SrcEVT.getSimpleVT();
if (Ty->isFloatTy() && !Subtarget->hasVFP2Base())
return false;
if (Ty->isDoubleTy() && (!Subtarget->hasVFP2Base() || !Subtarget->hasFP64()))
return false;
// Check to see if the 2nd operand is a constant that we can encode directly
// in the compare.
int Imm = 0;
bool UseImm = false;
bool isNegativeImm = false;
// FIXME: At -O0 we don't have anything that canonicalizes operand order.
// Thus, Src1Value may be a ConstantInt, but we're missing it.
if (const ConstantInt *ConstInt = dyn_cast<ConstantInt>(Src2Value)) {
if (SrcVT == MVT::i32 || SrcVT == MVT::i16 || SrcVT == MVT::i8 ||
SrcVT == MVT::i1) {
const APInt &CIVal = ConstInt->getValue();
Imm = (isZExt) ? (int)CIVal.getZExtValue() : (int)CIVal.getSExtValue();
// For INT_MIN/LONG_MIN (i.e., 0x80000000) we need to use a cmp, rather
// then a cmn, because there is no way to represent 2147483648 as a
// signed 32-bit int.
if (Imm < 0 && Imm != (int)0x80000000) {
isNegativeImm = true;
Imm = -Imm;
}
UseImm = isThumb2 ? (ARM_AM::getT2SOImmVal(Imm) != -1) :
(ARM_AM::getSOImmVal(Imm) != -1);
}
} else if (const ConstantFP *ConstFP = dyn_cast<ConstantFP>(Src2Value)) {
if (SrcVT == MVT::f32 || SrcVT == MVT::f64)
if (ConstFP->isZero() && !ConstFP->isNegative())
UseImm = true;
}
unsigned CmpOpc;
bool isICmp = true;
bool needsExt = false;
switch (SrcVT.SimpleTy) {
default: return false;
// TODO: Verify compares.
case MVT::f32:
isICmp = false;
CmpOpc = UseImm ? ARM::VCMPZS : ARM::VCMPS;
break;
case MVT::f64:
isICmp = false;
CmpOpc = UseImm ? ARM::VCMPZD : ARM::VCMPD;
break;
case MVT::i1:
case MVT::i8:
case MVT::i16:
needsExt = true;
[[fallthrough]];
case MVT::i32:
if (isThumb2) {
if (!UseImm)
CmpOpc = ARM::t2CMPrr;
else
CmpOpc = isNegativeImm ? ARM::t2CMNri : ARM::t2CMPri;
} else {
if (!UseImm)
CmpOpc = ARM::CMPrr;
else
CmpOpc = isNegativeImm ? ARM::CMNri : ARM::CMPri;
}
break;
}
Register SrcReg1 = getRegForValue(Src1Value);
if (SrcReg1 == 0) return false;
unsigned SrcReg2 = 0;
if (!UseImm) {
SrcReg2 = getRegForValue(Src2Value);
if (SrcReg2 == 0) return false;
}
// We have i1, i8, or i16, we need to either zero extend or sign extend.
if (needsExt) {
SrcReg1 = ARMEmitIntExt(SrcVT, SrcReg1, MVT::i32, isZExt);
if (SrcReg1 == 0) return false;
if (!UseImm) {
SrcReg2 = ARMEmitIntExt(SrcVT, SrcReg2, MVT::i32, isZExt);
if (SrcReg2 == 0) return false;
}
}
const MCInstrDesc &II = TII.get(CmpOpc);
SrcReg1 = constrainOperandRegClass(II, SrcReg1, 0);
if (!UseImm) {
SrcReg2 = constrainOperandRegClass(II, SrcReg2, 1);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, II)
.addReg(SrcReg1).addReg(SrcReg2));
} else {
MachineInstrBuilder MIB;
MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, II)
.addReg(SrcReg1);
// Only add immediate for icmp as the immediate for fcmp is an implicit 0.0.
if (isICmp)
MIB.addImm(Imm);
AddOptionalDefs(MIB);
}
// For floating point we need to move the result to a comparison register
// that we can then use for branches.
if (Ty->isFloatTy() || Ty->isDoubleTy())
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::FMSTAT)));
return true;
}
bool ARMFastISel::SelectCmp(const Instruction *I) {
const CmpInst *CI = cast<CmpInst>(I);
// Get the compare predicate.
ARMCC::CondCodes ARMPred = getComparePred(CI->getPredicate());
// We may not handle every CC for now.
if (ARMPred == ARMCC::AL) return false;
// Emit the compare.
if (!ARMEmitCmp(CI->getOperand(0), CI->getOperand(1), CI->isUnsigned()))
return false;
// Now set a register based on the comparison. Explicitly set the predicates
// here.
unsigned MovCCOpc = isThumb2 ? ARM::t2MOVCCi : ARM::MOVCCi;
const TargetRegisterClass *RC = isThumb2 ? &ARM::rGPRRegClass
: &ARM::GPRRegClass;
Register DestReg = createResultReg(RC);
Constant *Zero = ConstantInt::get(Type::getInt32Ty(*Context), 0);
unsigned ZeroReg = fastMaterializeConstant(Zero);
// ARMEmitCmp emits a FMSTAT when necessary, so it's always safe to use CPSR.
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(MovCCOpc), DestReg)
.addReg(ZeroReg).addImm(1)
.addImm(ARMPred).addReg(ARM::CPSR);
updateValueMap(I, DestReg);
return true;
}
bool ARMFastISel::SelectFPExt(const Instruction *I) {
// Make sure we have VFP and that we're extending float to double.
if (!Subtarget->hasVFP2Base() || !Subtarget->hasFP64()) return false;
Value *V = I->getOperand(0);
if (!I->getType()->isDoubleTy() ||
!V->getType()->isFloatTy()) return false;
Register Op = getRegForValue(V);
if (Op == 0) return false;
Register Result = createResultReg(&ARM::DPRRegClass);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::VCVTDS), Result)
.addReg(Op));
updateValueMap(I, Result);
return true;
}
bool ARMFastISel::SelectFPTrunc(const Instruction *I) {
// Make sure we have VFP and that we're truncating double to float.
if (!Subtarget->hasVFP2Base() || !Subtarget->hasFP64()) return false;
Value *V = I->getOperand(0);
if (!(I->getType()->isFloatTy() &&
V->getType()->isDoubleTy())) return false;
Register Op = getRegForValue(V);
if (Op == 0) return false;
Register Result = createResultReg(&ARM::SPRRegClass);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::VCVTSD), Result)
.addReg(Op));
updateValueMap(I, Result);
return true;
}
bool ARMFastISel::SelectIToFP(const Instruction *I, bool isSigned) {
// Make sure we have VFP.
if (!Subtarget->hasVFP2Base()) return false;
MVT DstVT;
Type *Ty = I->getType();
if (!isTypeLegal(Ty, DstVT))
return false;
Value *Src = I->getOperand(0);
EVT SrcEVT = TLI.getValueType(DL, Src->getType(), true);
if (!SrcEVT.isSimple())
return false;
MVT SrcVT = SrcEVT.getSimpleVT();
if (SrcVT != MVT::i32 && SrcVT != MVT::i16 && SrcVT != MVT::i8)
return false;
Register SrcReg = getRegForValue(Src);
if (SrcReg == 0) return false;
// Handle sign-extension.
if (SrcVT == MVT::i16 || SrcVT == MVT::i8) {
SrcReg = ARMEmitIntExt(SrcVT, SrcReg, MVT::i32,
/*isZExt*/!isSigned);
if (SrcReg == 0) return false;
}
// The conversion routine works on fp-reg to fp-reg and the operand above
// was an integer, move it to the fp registers if possible.
unsigned FP = ARMMoveToFPReg(MVT::f32, SrcReg);
if (FP == 0) return false;
unsigned Opc;
if (Ty->isFloatTy()) Opc = isSigned ? ARM::VSITOS : ARM::VUITOS;
else if (Ty->isDoubleTy() && Subtarget->hasFP64())
Opc = isSigned ? ARM::VSITOD : ARM::VUITOD;
else return false;
Register ResultReg = createResultReg(TLI.getRegClassFor(DstVT));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), ResultReg).addReg(FP));
updateValueMap(I, ResultReg);
return true;
}
bool ARMFastISel::SelectFPToI(const Instruction *I, bool isSigned) {
// Make sure we have VFP.
if (!Subtarget->hasVFP2Base()) return false;
MVT DstVT;
Type *RetTy = I->getType();
if (!isTypeLegal(RetTy, DstVT))
return false;
Register Op = getRegForValue(I->getOperand(0));
if (Op == 0) return false;
unsigned Opc;
Type *OpTy = I->getOperand(0)->getType();
if (OpTy->isFloatTy()) Opc = isSigned ? ARM::VTOSIZS : ARM::VTOUIZS;
else if (OpTy->isDoubleTy() && Subtarget->hasFP64())
Opc = isSigned ? ARM::VTOSIZD : ARM::VTOUIZD;
else return false;
// f64->s32/u32 or f32->s32/u32 both need an intermediate f32 reg.
Register ResultReg = createResultReg(TLI.getRegClassFor(MVT::f32));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), ResultReg).addReg(Op));
// This result needs to be in an integer register, but the conversion only
// takes place in fp-regs.
unsigned IntReg = ARMMoveToIntReg(DstVT, ResultReg);
if (IntReg == 0) return false;
updateValueMap(I, IntReg);
return true;
}
bool ARMFastISel::SelectSelect(const Instruction *I) {
MVT VT;
if (!isTypeLegal(I->getType(), VT))
return false;
// Things need to be register sized for register moves.
if (VT != MVT::i32) return false;
Register CondReg = getRegForValue(I->getOperand(0));
if (CondReg == 0) return false;
Register Op1Reg = getRegForValue(I->getOperand(1));
if (Op1Reg == 0) return false;
// Check to see if we can use an immediate in the conditional move.
int Imm = 0;
bool UseImm = false;
bool isNegativeImm = false;
if (const ConstantInt *ConstInt = dyn_cast<ConstantInt>(I->getOperand(2))) {
assert(VT == MVT::i32 && "Expecting an i32.");
Imm = (int)ConstInt->getValue().getZExtValue();
if (Imm < 0) {
isNegativeImm = true;
Imm = ~Imm;
}
UseImm = isThumb2 ? (ARM_AM::getT2SOImmVal(Imm) != -1) :
(ARM_AM::getSOImmVal(Imm) != -1);
}
unsigned Op2Reg = 0;
if (!UseImm) {
Op2Reg = getRegForValue(I->getOperand(2));
if (Op2Reg == 0) return false;
}
unsigned TstOpc = isThumb2 ? ARM::t2TSTri : ARM::TSTri;
CondReg = constrainOperandRegClass(TII.get(TstOpc), CondReg, 0);
AddOptionalDefs(
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(TstOpc))
.addReg(CondReg)
.addImm(1));
unsigned MovCCOpc;
const TargetRegisterClass *RC;
if (!UseImm) {
RC = isThumb2 ? &ARM::tGPRRegClass : &ARM::GPRRegClass;
MovCCOpc = isThumb2 ? ARM::t2MOVCCr : ARM::MOVCCr;
} else {
RC = isThumb2 ? &ARM::rGPRRegClass : &ARM::GPRRegClass;
if (!isNegativeImm)
MovCCOpc = isThumb2 ? ARM::t2MOVCCi : ARM::MOVCCi;
else
MovCCOpc = isThumb2 ? ARM::t2MVNCCi : ARM::MVNCCi;
}
Register ResultReg = createResultReg(RC);
if (!UseImm) {
Op2Reg = constrainOperandRegClass(TII.get(MovCCOpc), Op2Reg, 1);
Op1Reg = constrainOperandRegClass(TII.get(MovCCOpc), Op1Reg, 2);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(MovCCOpc),
ResultReg)
.addReg(Op2Reg)
.addReg(Op1Reg)
.addImm(ARMCC::NE)
.addReg(ARM::CPSR);
} else {
Op1Reg = constrainOperandRegClass(TII.get(MovCCOpc), Op1Reg, 1);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(MovCCOpc),
ResultReg)
.addReg(Op1Reg)
.addImm(Imm)
.addImm(ARMCC::EQ)
.addReg(ARM::CPSR);
}
updateValueMap(I, ResultReg);
return true;
}
bool ARMFastISel::SelectDiv(const Instruction *I, bool isSigned) {
MVT VT;
Type *Ty = I->getType();
if (!isTypeLegal(Ty, VT))
return false;
// If we have integer div support we should have selected this automagically.
// In case we have a real miss go ahead and return false and we'll pick
// it up later.
if (Subtarget->hasDivideInThumbMode())
return false;
// Otherwise emit a libcall.
RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
if (VT == MVT::i8)
LC = isSigned ? RTLIB::SDIV_I8 : RTLIB::UDIV_I8;
else if (VT == MVT::i16)
LC = isSigned ? RTLIB::SDIV_I16 : RTLIB::UDIV_I16;
else if (VT == MVT::i32)
LC = isSigned ? RTLIB::SDIV_I32 : RTLIB::UDIV_I32;
else if (VT == MVT::i64)
LC = isSigned ? RTLIB::SDIV_I64 : RTLIB::UDIV_I64;
else if (VT == MVT::i128)
LC = isSigned ? RTLIB::SDIV_I128 : RTLIB::UDIV_I128;
assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unsupported SDIV!");
return ARMEmitLibcall(I, LC);
}
bool ARMFastISel::SelectRem(const Instruction *I, bool isSigned) {
MVT VT;
Type *Ty = I->getType();
if (!isTypeLegal(Ty, VT))
return false;
// Many ABIs do not provide a libcall for standalone remainder, so we need to
// use divrem (see the RTABI 4.3.1). Since FastISel can't handle non-double
// multi-reg returns, we'll have to bail out.
if (!TLI.hasStandaloneRem(VT)) {
return false;
}
RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
if (VT == MVT::i8)
LC = isSigned ? RTLIB::SREM_I8 : RTLIB::UREM_I8;
else if (VT == MVT::i16)
LC = isSigned ? RTLIB::SREM_I16 : RTLIB::UREM_I16;
else if (VT == MVT::i32)
LC = isSigned ? RTLIB::SREM_I32 : RTLIB::UREM_I32;
else if (VT == MVT::i64)
LC = isSigned ? RTLIB::SREM_I64 : RTLIB::UREM_I64;
else if (VT == MVT::i128)
LC = isSigned ? RTLIB::SREM_I128 : RTLIB::UREM_I128;
assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unsupported SREM!");
return ARMEmitLibcall(I, LC);
}
bool ARMFastISel::SelectBinaryIntOp(const Instruction *I, unsigned ISDOpcode) {
EVT DestVT = TLI.getValueType(DL, I->getType(), true);
// We can get here in the case when we have a binary operation on a non-legal
// type and the target independent selector doesn't know how to handle it.
if (DestVT != MVT::i16 && DestVT != MVT::i8 && DestVT != MVT::i1)
return false;
unsigned Opc;
switch (ISDOpcode) {
default: return false;
case ISD::ADD:
Opc = isThumb2 ? ARM::t2ADDrr : ARM::ADDrr;
break;
case ISD::OR:
Opc = isThumb2 ? ARM::t2ORRrr : ARM::ORRrr;
break;
case ISD::SUB:
Opc = isThumb2 ? ARM::t2SUBrr : ARM::SUBrr;
break;
}
Register SrcReg1 = getRegForValue(I->getOperand(0));
if (SrcReg1 == 0) return false;
// TODO: Often the 2nd operand is an immediate, which can be encoded directly
// in the instruction, rather then materializing the value in a register.
Register SrcReg2 = getRegForValue(I->getOperand(1));
if (SrcReg2 == 0) return false;
Register ResultReg = createResultReg(&ARM::GPRnopcRegClass);
SrcReg1 = constrainOperandRegClass(TII.get(Opc), SrcReg1, 1);
SrcReg2 = constrainOperandRegClass(TII.get(Opc), SrcReg2, 2);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), ResultReg)
.addReg(SrcReg1).addReg(SrcReg2));
updateValueMap(I, ResultReg);
return true;
}
bool ARMFastISel::SelectBinaryFPOp(const Instruction *I, unsigned ISDOpcode) {
EVT FPVT = TLI.getValueType(DL, I->getType(), true);
if (!FPVT.isSimple()) return false;
MVT VT = FPVT.getSimpleVT();
// FIXME: Support vector types where possible.
if (VT.isVector())
return false;
// We can get here in the case when we want to use NEON for our fp
// operations, but can't figure out how to. Just use the vfp instructions
// if we have them.
// FIXME: It'd be nice to use NEON instructions.
Type *Ty = I->getType();
if (Ty->isFloatTy() && !Subtarget->hasVFP2Base())
return false;
if (Ty->isDoubleTy() && (!Subtarget->hasVFP2Base() || !Subtarget->hasFP64()))
return false;
unsigned Opc;
bool is64bit = VT == MVT::f64 || VT == MVT::i64;
switch (ISDOpcode) {
default: return false;
case ISD::FADD:
Opc = is64bit ? ARM::VADDD : ARM::VADDS;
break;
case ISD::FSUB:
Opc = is64bit ? ARM::VSUBD : ARM::VSUBS;
break;
case ISD::FMUL:
Opc = is64bit ? ARM::VMULD : ARM::VMULS;
break;
}
Register Op1 = getRegForValue(I->getOperand(0));
if (Op1 == 0) return false;
Register Op2 = getRegForValue(I->getOperand(1));
if (Op2 == 0) return false;
Register ResultReg = createResultReg(TLI.getRegClassFor(VT.SimpleTy));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), ResultReg)
.addReg(Op1).addReg(Op2));
updateValueMap(I, ResultReg);
return true;
}
// Call Handling Code
// This is largely taken directly from CCAssignFnForNode
// TODO: We may not support all of this.
CCAssignFn *ARMFastISel::CCAssignFnForCall(CallingConv::ID CC,
bool Return,
bool isVarArg) {
switch (CC) {
default:
report_fatal_error("Unsupported calling convention");
case CallingConv::Fast:
if (Subtarget->hasVFP2Base() && !isVarArg) {
if (!Subtarget->isAAPCS_ABI())
return (Return ? RetFastCC_ARM_APCS : FastCC_ARM_APCS);
// For AAPCS ABI targets, just use VFP variant of the calling convention.
return (Return ? RetCC_ARM_AAPCS_VFP : CC_ARM_AAPCS_VFP);
}
[[fallthrough]];
case CallingConv::C:
case CallingConv::CXX_FAST_TLS:
// Use target triple & subtarget features to do actual dispatch.
if (Subtarget->isAAPCS_ABI()) {
if (Subtarget->hasFPRegs() &&
TM.Options.FloatABIType == FloatABI::Hard && !isVarArg)
return (Return ? RetCC_ARM_AAPCS_VFP: CC_ARM_AAPCS_VFP);
else
return (Return ? RetCC_ARM_AAPCS: CC_ARM_AAPCS);
} else {
return (Return ? RetCC_ARM_APCS: CC_ARM_APCS);
}
case CallingConv::ARM_AAPCS_VFP:
case CallingConv::Swift:
case CallingConv::SwiftTail:
if (!isVarArg)
return (Return ? RetCC_ARM_AAPCS_VFP: CC_ARM_AAPCS_VFP);
// Fall through to soft float variant, variadic functions don't
// use hard floating point ABI.
[[fallthrough]];
case CallingConv::ARM_AAPCS:
return (Return ? RetCC_ARM_AAPCS: CC_ARM_AAPCS);
case CallingConv::ARM_APCS:
return (Return ? RetCC_ARM_APCS: CC_ARM_APCS);
case CallingConv::GHC:
if (Return)
report_fatal_error("Can't return in GHC call convention");
else
return CC_ARM_APCS_GHC;
case CallingConv::CFGuard_Check:
return (Return ? RetCC_ARM_AAPCS : CC_ARM_Win32_CFGuard_Check);
}
}
bool ARMFastISel::ProcessCallArgs(SmallVectorImpl<Value*> &Args,
SmallVectorImpl<Register> &ArgRegs,
SmallVectorImpl<MVT> &ArgVTs,
SmallVectorImpl<ISD::ArgFlagsTy> &ArgFlags,
SmallVectorImpl<Register> &RegArgs,
CallingConv::ID CC,
unsigned &NumBytes,
bool isVarArg) {
SmallVector<CCValAssign, 16> ArgLocs;
CCState CCInfo(CC, isVarArg, *FuncInfo.MF, ArgLocs, *Context);
CCInfo.AnalyzeCallOperands(ArgVTs, ArgFlags,
CCAssignFnForCall(CC, false, isVarArg));
// Check that we can handle all of the arguments. If we can't, then bail out
// now before we add code to the MBB.
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
CCValAssign &VA = ArgLocs[i];
MVT ArgVT = ArgVTs[VA.getValNo()];
// We don't handle NEON/vector parameters yet.
if (ArgVT.isVector() || ArgVT.getSizeInBits() > 64)
return false;
// Now copy/store arg to correct locations.
if (VA.isRegLoc() && !VA.needsCustom()) {
continue;
} else if (VA.needsCustom()) {
// TODO: We need custom lowering for vector (v2f64) args.
if (VA.getLocVT() != MVT::f64 ||
// TODO: Only handle register args for now.
!VA.isRegLoc() || !ArgLocs[++i].isRegLoc())
return false;
} else {
switch (ArgVT.SimpleTy) {
default:
return false;
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
break;
case MVT::f32:
if (!Subtarget->hasVFP2Base())
return false;
break;
case MVT::f64:
if (!Subtarget->hasVFP2Base())
return false;
break;
}
}
}
// At the point, we are able to handle the call's arguments in fast isel.
// Get a count of how many bytes are to be pushed on the stack.
NumBytes = CCInfo.getStackSize();
// Issue CALLSEQ_START
unsigned AdjStackDown = TII.getCallFrameSetupOpcode();
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(AdjStackDown))
.addImm(NumBytes).addImm(0));
// Process the args.
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
CCValAssign &VA = ArgLocs[i];
const Value *ArgVal = Args[VA.getValNo()];
Register Arg = ArgRegs[VA.getValNo()];
MVT ArgVT = ArgVTs[VA.getValNo()];
assert((!ArgVT.isVector() && ArgVT.getSizeInBits() <= 64) &&
"We don't handle NEON/vector parameters yet.");
// Handle arg promotion, etc.
switch (VA.getLocInfo()) {
case CCValAssign::Full: break;
case CCValAssign::SExt: {
MVT DestVT = VA.getLocVT();
Arg = ARMEmitIntExt(ArgVT, Arg, DestVT, /*isZExt*/false);
assert(Arg != 0 && "Failed to emit a sext");
ArgVT = DestVT;
break;
}
case CCValAssign::AExt:
// Intentional fall-through. Handle AExt and ZExt.
case CCValAssign::ZExt: {
MVT DestVT = VA.getLocVT();
Arg = ARMEmitIntExt(ArgVT, Arg, DestVT, /*isZExt*/true);
assert(Arg != 0 && "Failed to emit a zext");
ArgVT = DestVT;
break;
}
case CCValAssign::BCvt: {
unsigned BC = fastEmit_r(ArgVT, VA.getLocVT(), ISD::BITCAST, Arg);
assert(BC != 0 && "Failed to emit a bitcast!");
Arg = BC;
ArgVT = VA.getLocVT();
break;
}
default: llvm_unreachable("Unknown arg promotion!");
}
// Now copy/store arg to correct locations.
if (VA.isRegLoc() && !VA.needsCustom()) {
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(TargetOpcode::COPY), VA.getLocReg()).addReg(Arg);
RegArgs.push_back(VA.getLocReg());
} else if (VA.needsCustom()) {
// TODO: We need custom lowering for vector (v2f64) args.
assert(VA.getLocVT() == MVT::f64 &&
"Custom lowering for v2f64 args not available");
// FIXME: ArgLocs[++i] may extend beyond ArgLocs.size()
CCValAssign &NextVA = ArgLocs[++i];
assert(VA.isRegLoc() && NextVA.isRegLoc() &&
"We only handle register args!");
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::VMOVRRD), VA.getLocReg())
.addReg(NextVA.getLocReg(), RegState::Define)
.addReg(Arg));
RegArgs.push_back(VA.getLocReg());
RegArgs.push_back(NextVA.getLocReg());
} else {
assert(VA.isMemLoc());
// Need to store on the stack.
// Don't emit stores for undef values.
if (isa<UndefValue>(ArgVal))
continue;
Address Addr;
Addr.BaseType = Address::RegBase;
Addr.Base.Reg = ARM::SP;
Addr.Offset = VA.getLocMemOffset();
bool EmitRet = ARMEmitStore(ArgVT, Arg, Addr); (void)EmitRet;
assert(EmitRet && "Could not emit a store for argument!");
}
}
return true;
}
bool ARMFastISel::FinishCall(MVT RetVT, SmallVectorImpl<Register> &UsedRegs,
const Instruction *I, CallingConv::ID CC,
unsigned &NumBytes, bool isVarArg) {
// Issue CALLSEQ_END
unsigned AdjStackUp = TII.getCallFrameDestroyOpcode();
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(AdjStackUp))
.addImm(NumBytes).addImm(-1ULL));
// Now the return value.
if (RetVT != MVT::isVoid) {
SmallVector<CCValAssign, 16> RVLocs;
CCState CCInfo(CC, isVarArg, *FuncInfo.MF, RVLocs, *Context);
CCInfo.AnalyzeCallResult(RetVT, CCAssignFnForCall(CC, true, isVarArg));
// Copy all of the result registers out of their specified physreg.
if (RVLocs.size() == 2 && RetVT == MVT::f64) {
// For this move we copy into two registers and then move into the
// double fp reg we want.
MVT DestVT = RVLocs[0].getValVT();
const TargetRegisterClass* DstRC = TLI.getRegClassFor(DestVT);
Register ResultReg = createResultReg(DstRC);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::VMOVDRR), ResultReg)
.addReg(RVLocs[0].getLocReg())
.addReg(RVLocs[1].getLocReg()));
UsedRegs.push_back(RVLocs[0].getLocReg());
UsedRegs.push_back(RVLocs[1].getLocReg());
// Finally update the result.
updateValueMap(I, ResultReg);
} else {
assert(RVLocs.size() == 1 &&"Can't handle non-double multi-reg retvals!");
MVT CopyVT = RVLocs[0].getValVT();
// Special handling for extended integers.
if (RetVT == MVT::i1 || RetVT == MVT::i8 || RetVT == MVT::i16)
CopyVT = MVT::i32;
const TargetRegisterClass* DstRC = TLI.getRegClassFor(CopyVT);
Register ResultReg = createResultReg(DstRC);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(TargetOpcode::COPY),
ResultReg).addReg(RVLocs[0].getLocReg());
UsedRegs.push_back(RVLocs[0].getLocReg());
// Finally update the result.
updateValueMap(I, ResultReg);
}
}
return true;
}
bool ARMFastISel::SelectRet(const Instruction *I) {
const ReturnInst *Ret = cast<ReturnInst>(I);
const Function &F = *I->getParent()->getParent();
const bool IsCmseNSEntry = F.hasFnAttribute("cmse_nonsecure_entry");
if (!FuncInfo.CanLowerReturn)
return false;
if (TLI.supportSwiftError() &&
F.getAttributes().hasAttrSomewhere(Attribute::SwiftError))
return false;
if (TLI.supportSplitCSR(FuncInfo.MF))
return false;
// Build a list of return value registers.
SmallVector<unsigned, 4> RetRegs;
CallingConv::ID CC = F.getCallingConv();
if (Ret->getNumOperands() > 0) {
SmallVector<ISD::OutputArg, 4> Outs;
GetReturnInfo(CC, F.getReturnType(), F.getAttributes(), Outs, TLI, DL);
// Analyze operands of the call, assigning locations to each operand.
SmallVector<CCValAssign, 16> ValLocs;
CCState CCInfo(CC, F.isVarArg(), *FuncInfo.MF, ValLocs, I->getContext());
CCInfo.AnalyzeReturn(Outs, CCAssignFnForCall(CC, true /* is Ret */,
F.isVarArg()));
const Value *RV = Ret->getOperand(0);
Register Reg = getRegForValue(RV);
if (Reg == 0)
return false;
// Only handle a single return value for now.
if (ValLocs.size() != 1)
return false;
CCValAssign &VA = ValLocs[0];
// Don't bother handling odd stuff for now.
if (VA.getLocInfo() != CCValAssign::Full)
return false;
// Only handle register returns for now.
if (!VA.isRegLoc())
return false;
unsigned SrcReg = Reg + VA.getValNo();
EVT RVEVT = TLI.getValueType(DL, RV->getType());
if (!RVEVT.isSimple()) return false;
MVT RVVT = RVEVT.getSimpleVT();
MVT DestVT = VA.getValVT();
// Special handling for extended integers.
if (RVVT != DestVT) {
if (RVVT != MVT::i1 && RVVT != MVT::i8 && RVVT != MVT::i16)
return false;
assert(DestVT == MVT::i32 && "ARM should always ext to i32");
// Perform extension if flagged as either zext or sext. Otherwise, do
// nothing.
if (Outs[0].Flags.isZExt() || Outs[0].Flags.isSExt()) {
SrcReg = ARMEmitIntExt(RVVT, SrcReg, DestVT, Outs[0].Flags.isZExt());
if (SrcReg == 0) return false;
}
}
// Make the copy.
Register DstReg = VA.getLocReg();
const TargetRegisterClass* SrcRC = MRI.getRegClass(SrcReg);
// Avoid a cross-class copy. This is very unlikely.
if (!SrcRC->contains(DstReg))
return false;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(TargetOpcode::COPY), DstReg).addReg(SrcReg);
// Add register to return instruction.
RetRegs.push_back(VA.getLocReg());
}
unsigned RetOpc;
if (IsCmseNSEntry)
if (isThumb2)
RetOpc = ARM::tBXNS_RET;
else
llvm_unreachable("CMSE not valid for non-Thumb targets");
else
RetOpc = Subtarget->getReturnOpcode();
MachineInstrBuilder MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(RetOpc));
AddOptionalDefs(MIB);
for (unsigned R : RetRegs)
MIB.addReg(R, RegState::Implicit);
return true;
}
unsigned ARMFastISel::ARMSelectCallOp(bool UseReg) {
if (UseReg)
return isThumb2 ? gettBLXrOpcode(*MF) : getBLXOpcode(*MF);
else
return isThumb2 ? ARM::tBL : ARM::BL;
}
unsigned ARMFastISel::getLibcallReg(const Twine &Name) {
// Manually compute the global's type to avoid building it when unnecessary.
Type *GVTy = PointerType::get(*Context, /*AS=*/0);
EVT LCREVT = TLI.getValueType(DL, GVTy);
if (!LCREVT.isSimple()) return 0;
GlobalValue *GV = M.getNamedGlobal(Name.str());
if (!GV)
GV = new GlobalVariable(M, Type::getInt32Ty(*Context), false,
GlobalValue::ExternalLinkage, nullptr, Name);
return ARMMaterializeGV(GV, LCREVT.getSimpleVT());
}
// A quick function that will emit a call for a named libcall in F with the
// vector of passed arguments for the Instruction in I. We can assume that we
// can emit a call for any libcall we can produce. This is an abridged version
// of the full call infrastructure since we won't need to worry about things
// like computed function pointers or strange arguments at call sites.
// TODO: Try to unify this and the normal call bits for ARM, then try to unify
// with X86.
bool ARMFastISel::ARMEmitLibcall(const Instruction *I, RTLIB::Libcall Call) {
CallingConv::ID CC = TLI.getLibcallCallingConv(Call);
// Handle *simple* calls for now.
Type *RetTy = I->getType();
MVT RetVT;
if (RetTy->isVoidTy())
RetVT = MVT::isVoid;
else if (!isTypeLegal(RetTy, RetVT))
return false;
// Can't handle non-double multi-reg retvals.
if (RetVT != MVT::isVoid && RetVT != MVT::i32) {
SmallVector<CCValAssign, 16> RVLocs;
CCState CCInfo(CC, false, *FuncInfo.MF, RVLocs, *Context);
CCInfo.AnalyzeCallResult(RetVT, CCAssignFnForCall(CC, true, false));
if (RVLocs.size() >= 2 && RetVT != MVT::f64)
return false;
}
// Set up the argument vectors.
SmallVector<Value*, 8> Args;
SmallVector<Register, 8> ArgRegs;
SmallVector<MVT, 8> ArgVTs;
SmallVector<ISD::ArgFlagsTy, 8> ArgFlags;
Args.reserve(I->getNumOperands());
ArgRegs.reserve(I->getNumOperands());
ArgVTs.reserve(I->getNumOperands());
ArgFlags.reserve(I->getNumOperands());
for (Value *Op : I->operands()) {
Register Arg = getRegForValue(Op);
if (Arg == 0) return false;
Type *ArgTy = Op->getType();
MVT ArgVT;
if (!isTypeLegal(ArgTy, ArgVT)) return false;
ISD::ArgFlagsTy Flags;
Flags.setOrigAlign(DL.getABITypeAlign(ArgTy));
Args.push_back(Op);
ArgRegs.push_back(Arg);
ArgVTs.push_back(ArgVT);
ArgFlags.push_back(Flags);
}
// Handle the arguments now that we've gotten them.
SmallVector<Register, 4> RegArgs;
unsigned NumBytes;
if (!ProcessCallArgs(Args, ArgRegs, ArgVTs, ArgFlags,
RegArgs, CC, NumBytes, false))
return false;
Register CalleeReg;
if (Subtarget->genLongCalls()) {
CalleeReg = getLibcallReg(TLI.getLibcallName(Call));
if (CalleeReg == 0) return false;
}
// Issue the call.
unsigned CallOpc = ARMSelectCallOp(Subtarget->genLongCalls());
MachineInstrBuilder MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt,
MIMD, TII.get(CallOpc));
// BL / BLX don't take a predicate, but tBL / tBLX do.
if (isThumb2)
MIB.add(predOps(ARMCC::AL));
if (Subtarget->genLongCalls()) {
CalleeReg =
constrainOperandRegClass(TII.get(CallOpc), CalleeReg, isThumb2 ? 2 : 0);
MIB.addReg(CalleeReg);
} else
MIB.addExternalSymbol(TLI.getLibcallName(Call));
// Add implicit physical register uses to the call.
for (Register R : RegArgs)
MIB.addReg(R, RegState::Implicit);
// Add a register mask with the call-preserved registers.
// Proper defs for return values will be added by setPhysRegsDeadExcept().
MIB.addRegMask(TRI.getCallPreservedMask(*FuncInfo.MF, CC));
// Finish off the call including any return values.
SmallVector<Register, 4> UsedRegs;
if (!FinishCall(RetVT, UsedRegs, I, CC, NumBytes, false)) return false;
// Set all unused physreg defs as dead.
static_cast<MachineInstr *>(MIB)->setPhysRegsDeadExcept(UsedRegs, TRI);
return true;
}
bool ARMFastISel::SelectCall(const Instruction *I,
const char *IntrMemName = nullptr) {
const CallInst *CI = cast<CallInst>(I);
const Value *Callee = CI->getCalledOperand();
// Can't handle inline asm.
if (isa<InlineAsm>(Callee)) return false;
// Allow SelectionDAG isel to handle tail calls.
if (CI->isTailCall()) return false;
// Check the calling convention.
CallingConv::ID CC = CI->getCallingConv();
// TODO: Avoid some calling conventions?
FunctionType *FTy = CI->getFunctionType();
bool isVarArg = FTy->isVarArg();
// Handle *simple* calls for now.
Type *RetTy = I->getType();
MVT RetVT;
if (RetTy->isVoidTy())
RetVT = MVT::isVoid;
else if (!isTypeLegal(RetTy, RetVT) && RetVT != MVT::i16 &&
RetVT != MVT::i8 && RetVT != MVT::i1)
return false;
// Can't handle non-double multi-reg retvals.
if (RetVT != MVT::isVoid && RetVT != MVT::i1 && RetVT != MVT::i8 &&
RetVT != MVT::i16 && RetVT != MVT::i32) {
SmallVector<CCValAssign, 16> RVLocs;
CCState CCInfo(CC, isVarArg, *FuncInfo.MF, RVLocs, *Context);
CCInfo.AnalyzeCallResult(RetVT, CCAssignFnForCall(CC, true, isVarArg));
if (RVLocs.size() >= 2 && RetVT != MVT::f64)
return false;
}
// Set up the argument vectors.
SmallVector<Value*, 8> Args;
SmallVector<Register, 8> ArgRegs;
SmallVector<MVT, 8> ArgVTs;
SmallVector<ISD::ArgFlagsTy, 8> ArgFlags;
unsigned arg_size = CI->arg_size();
Args.reserve(arg_size);
ArgRegs.reserve(arg_size);
ArgVTs.reserve(arg_size);
ArgFlags.reserve(arg_size);
for (auto ArgI = CI->arg_begin(), ArgE = CI->arg_end(); ArgI != ArgE; ++ArgI) {
// If we're lowering a memory intrinsic instead of a regular call, skip the
// last argument, which shouldn't be passed to the underlying function.
if (IntrMemName && ArgE - ArgI <= 1)
break;
ISD::ArgFlagsTy Flags;
unsigned ArgIdx = ArgI - CI->arg_begin();
if (CI->paramHasAttr(ArgIdx, Attribute::SExt))
Flags.setSExt();
if (CI->paramHasAttr(ArgIdx, Attribute::ZExt))
Flags.setZExt();
// FIXME: Only handle *easy* calls for now.
if (CI->paramHasAttr(ArgIdx, Attribute::InReg) ||
CI->paramHasAttr(ArgIdx, Attribute::StructRet) ||
CI->paramHasAttr(ArgIdx, Attribute::SwiftSelf) ||
CI->paramHasAttr(ArgIdx, Attribute::SwiftError) ||
CI->paramHasAttr(ArgIdx, Attribute::Nest) ||
CI->paramHasAttr(ArgIdx, Attribute::ByVal))
return false;
Type *ArgTy = (*ArgI)->getType();
MVT ArgVT;
if (!isTypeLegal(ArgTy, ArgVT) && ArgVT != MVT::i16 && ArgVT != MVT::i8 &&
ArgVT != MVT::i1)
return false;
Register Arg = getRegForValue(*ArgI);
if (!Arg.isValid())
return false;
Flags.setOrigAlign(DL.getABITypeAlign(ArgTy));
Args.push_back(*ArgI);
ArgRegs.push_back(Arg);
ArgVTs.push_back(ArgVT);
ArgFlags.push_back(Flags);
}
// Handle the arguments now that we've gotten them.
SmallVector<Register, 4> RegArgs;
unsigned NumBytes;
if (!ProcessCallArgs(Args, ArgRegs, ArgVTs, ArgFlags,
RegArgs, CC, NumBytes, isVarArg))
return false;
bool UseReg = false;
const GlobalValue *GV = dyn_cast<GlobalValue>(Callee);
if (!GV || Subtarget->genLongCalls()) UseReg = true;
Register CalleeReg;
if (UseReg) {
if (IntrMemName)
CalleeReg = getLibcallReg(IntrMemName);
else
CalleeReg = getRegForValue(Callee);
if (CalleeReg == 0) return false;
}
// Issue the call.
unsigned CallOpc = ARMSelectCallOp(UseReg);
MachineInstrBuilder MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt,
MIMD, TII.get(CallOpc));
// ARM calls don't take a predicate, but tBL / tBLX do.
if(isThumb2)
MIB.add(predOps(ARMCC::AL));
if (UseReg) {
CalleeReg =
constrainOperandRegClass(TII.get(CallOpc), CalleeReg, isThumb2 ? 2 : 0);
MIB.addReg(CalleeReg);
} else if (!IntrMemName)
MIB.addGlobalAddress(GV, 0, 0);
else
MIB.addExternalSymbol(IntrMemName, 0);
// Add implicit physical register uses to the call.
for (Register R : RegArgs)
MIB.addReg(R, RegState::Implicit);
// Add a register mask with the call-preserved registers.
// Proper defs for return values will be added by setPhysRegsDeadExcept().
MIB.addRegMask(TRI.getCallPreservedMask(*FuncInfo.MF, CC));
// Finish off the call including any return values.
SmallVector<Register, 4> UsedRegs;
if (!FinishCall(RetVT, UsedRegs, I, CC, NumBytes, isVarArg))
return false;
// Set all unused physreg defs as dead.
static_cast<MachineInstr *>(MIB)->setPhysRegsDeadExcept(UsedRegs, TRI);
return true;
}
bool ARMFastISel::ARMIsMemCpySmall(uint64_t Len) {
return Len <= 16;
}
bool ARMFastISel::ARMTryEmitSmallMemCpy(Address Dest, Address Src, uint64_t Len,
MaybeAlign Alignment) {
// Make sure we don't bloat code by inlining very large memcpy's.
if (!ARMIsMemCpySmall(Len))
return false;
while (Len) {
MVT VT;
if (!Alignment || *Alignment >= 4) {
if (Len >= 4)
VT = MVT::i32;
else if (Len >= 2)
VT = MVT::i16;
else {
assert(Len == 1 && "Expected a length of 1!");
VT = MVT::i8;
}
} else {
assert(Alignment && "Alignment is set in this branch");
// Bound based on alignment.
if (Len >= 2 && *Alignment == 2)
VT = MVT::i16;
else {
VT = MVT::i8;
}
}
bool RV;
Register ResultReg;
RV = ARMEmitLoad(VT, ResultReg, Src);
assert(RV && "Should be able to handle this load.");
RV = ARMEmitStore(VT, ResultReg, Dest);
assert(RV && "Should be able to handle this store.");
(void)RV;
unsigned Size = VT.getSizeInBits()/8;
Len -= Size;
Dest.Offset += Size;
Src.Offset += Size;
}
return true;
}
bool ARMFastISel::SelectIntrinsicCall(const IntrinsicInst &I) {
// FIXME: Handle more intrinsics.
switch (I.getIntrinsicID()) {
default: return false;
case Intrinsic::frameaddress: {
MachineFrameInfo &MFI = FuncInfo.MF->getFrameInfo();
MFI.setFrameAddressIsTaken(true);
unsigned LdrOpc = isThumb2 ? ARM::t2LDRi12 : ARM::LDRi12;
const TargetRegisterClass *RC = isThumb2 ? &ARM::tGPRRegClass
: &ARM::GPRRegClass;
const ARMBaseRegisterInfo *RegInfo =
static_cast<const ARMBaseRegisterInfo *>(Subtarget->getRegisterInfo());
Register FramePtr = RegInfo->getFrameRegister(*(FuncInfo.MF));
unsigned SrcReg = FramePtr;
// Recursively load frame address
// ldr r0 [fp]
// ldr r0 [r0]
// ldr r0 [r0]
// ...
unsigned DestReg;
unsigned Depth = cast<ConstantInt>(I.getOperand(0))->getZExtValue();
while (Depth--) {
DestReg = createResultReg(RC);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(LdrOpc), DestReg)
.addReg(SrcReg).addImm(0));
SrcReg = DestReg;
}
updateValueMap(&I, SrcReg);
return true;
}
case Intrinsic::memcpy:
case Intrinsic::memmove: {
const MemTransferInst &MTI = cast<MemTransferInst>(I);
// Don't handle volatile.
if (MTI.isVolatile())
return false;
// Disable inlining for memmove before calls to ComputeAddress. Otherwise,
// we would emit dead code because we don't currently handle memmoves.
bool isMemCpy = (I.getIntrinsicID() == Intrinsic::memcpy);
if (isa<ConstantInt>(MTI.getLength()) && isMemCpy) {
// Small memcpy's are common enough that we want to do them without a call
// if possible.
uint64_t Len = cast<ConstantInt>(MTI.getLength())->getZExtValue();
if (ARMIsMemCpySmall(Len)) {
Address Dest, Src;
if (!ARMComputeAddress(MTI.getRawDest(), Dest) ||
!ARMComputeAddress(MTI.getRawSource(), Src))
return false;
MaybeAlign Alignment;
if (MTI.getDestAlign() || MTI.getSourceAlign())
Alignment = std::min(MTI.getDestAlign().valueOrOne(),
MTI.getSourceAlign().valueOrOne());
if (ARMTryEmitSmallMemCpy(Dest, Src, Len, Alignment))
return true;
}
}
if (!MTI.getLength()->getType()->isIntegerTy(32))
return false;
if (MTI.getSourceAddressSpace() > 255 || MTI.getDestAddressSpace() > 255)
return false;
const char *IntrMemName = isa<MemCpyInst>(I) ? "memcpy" : "memmove";
return SelectCall(&I, IntrMemName);
}
case Intrinsic::memset: {
const MemSetInst &MSI = cast<MemSetInst>(I);
// Don't handle volatile.
if (MSI.isVolatile())
return false;
if (!MSI.getLength()->getType()->isIntegerTy(32))
return false;
if (MSI.getDestAddressSpace() > 255)
return false;
return SelectCall(&I, "memset");
}
case Intrinsic::trap: {
unsigned Opcode;
if (Subtarget->isThumb())
Opcode = ARM::tTRAP;
else
Opcode = Subtarget->useNaClTrap() ? ARM::TRAPNaCl : ARM::TRAP;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(Opcode));
return true;
}
}
}
bool ARMFastISel::SelectTrunc(const Instruction *I) {
// The high bits for a type smaller than the register size are assumed to be
// undefined.
Value *Op = I->getOperand(0);
EVT SrcVT, DestVT;
SrcVT = TLI.getValueType(DL, Op->getType(), true);
DestVT = TLI.getValueType(DL, I->getType(), true);
if (SrcVT != MVT::i32 && SrcVT != MVT::i16 && SrcVT != MVT::i8)
return false;
if (DestVT != MVT::i16 && DestVT != MVT::i8 && DestVT != MVT::i1)
return false;
Register SrcReg = getRegForValue(Op);
if (!SrcReg) return false;
// Because the high bits are undefined, a truncate doesn't generate
// any code.
updateValueMap(I, SrcReg);
return true;
}
unsigned ARMFastISel::ARMEmitIntExt(MVT SrcVT, unsigned SrcReg, MVT DestVT,
bool isZExt) {
if (DestVT != MVT::i32 && DestVT != MVT::i16 && DestVT != MVT::i8)
return 0;
if (SrcVT != MVT::i16 && SrcVT != MVT::i8 && SrcVT != MVT::i1)
return 0;
// Table of which combinations can be emitted as a single instruction,
// and which will require two.
static const uint8_t isSingleInstrTbl[3][2][2][2] = {
// ARM Thumb
// !hasV6Ops hasV6Ops !hasV6Ops hasV6Ops
// ext: s z s z s z s z
/* 1 */ { { { 0, 1 }, { 0, 1 } }, { { 0, 0 }, { 0, 1 } } },
/* 8 */ { { { 0, 1 }, { 1, 1 } }, { { 0, 0 }, { 1, 1 } } },
/* 16 */ { { { 0, 0 }, { 1, 1 } }, { { 0, 0 }, { 1, 1 } } }
};
// Target registers for:
// - For ARM can never be PC.
// - For 16-bit Thumb are restricted to lower 8 registers.
// - For 32-bit Thumb are restricted to non-SP and non-PC.
static const TargetRegisterClass *RCTbl[2][2] = {
// Instructions: Two Single
/* ARM */ { &ARM::GPRnopcRegClass, &ARM::GPRnopcRegClass },
/* Thumb */ { &ARM::tGPRRegClass, &ARM::rGPRRegClass }
};
// Table governing the instruction(s) to be emitted.
static const struct InstructionTable {
uint32_t Opc : 16;
uint32_t hasS : 1; // Some instructions have an S bit, always set it to 0.
uint32_t Shift : 7; // For shift operand addressing mode, used by MOVsi.
uint32_t Imm : 8; // All instructions have either a shift or a mask.
} IT[2][2][3][2] = {
{ // Two instructions (first is left shift, second is in this table).
{ // ARM Opc S Shift Imm
/* 1 bit sext */ { { ARM::MOVsi , 1, ARM_AM::asr , 31 },
/* 1 bit zext */ { ARM::MOVsi , 1, ARM_AM::lsr , 31 } },
/* 8 bit sext */ { { ARM::MOVsi , 1, ARM_AM::asr , 24 },
/* 8 bit zext */ { ARM::MOVsi , 1, ARM_AM::lsr , 24 } },
/* 16 bit sext */ { { ARM::MOVsi , 1, ARM_AM::asr , 16 },
/* 16 bit zext */ { ARM::MOVsi , 1, ARM_AM::lsr , 16 } }
},
{ // Thumb Opc S Shift Imm
/* 1 bit sext */ { { ARM::tASRri , 0, ARM_AM::no_shift, 31 },
/* 1 bit zext */ { ARM::tLSRri , 0, ARM_AM::no_shift, 31 } },
/* 8 bit sext */ { { ARM::tASRri , 0, ARM_AM::no_shift, 24 },
/* 8 bit zext */ { ARM::tLSRri , 0, ARM_AM::no_shift, 24 } },
/* 16 bit sext */ { { ARM::tASRri , 0, ARM_AM::no_shift, 16 },
/* 16 bit zext */ { ARM::tLSRri , 0, ARM_AM::no_shift, 16 } }
}
},
{ // Single instruction.
{ // ARM Opc S Shift Imm
/* 1 bit sext */ { { ARM::KILL , 0, ARM_AM::no_shift, 0 },
/* 1 bit zext */ { ARM::ANDri , 1, ARM_AM::no_shift, 1 } },
/* 8 bit sext */ { { ARM::SXTB , 0, ARM_AM::no_shift, 0 },
/* 8 bit zext */ { ARM::ANDri , 1, ARM_AM::no_shift, 255 } },
/* 16 bit sext */ { { ARM::SXTH , 0, ARM_AM::no_shift, 0 },
/* 16 bit zext */ { ARM::UXTH , 0, ARM_AM::no_shift, 0 } }
},
{ // Thumb Opc S Shift Imm
/* 1 bit sext */ { { ARM::KILL , 0, ARM_AM::no_shift, 0 },
/* 1 bit zext */ { ARM::t2ANDri, 1, ARM_AM::no_shift, 1 } },
/* 8 bit sext */ { { ARM::t2SXTB , 0, ARM_AM::no_shift, 0 },
/* 8 bit zext */ { ARM::t2ANDri, 1, ARM_AM::no_shift, 255 } },
/* 16 bit sext */ { { ARM::t2SXTH , 0, ARM_AM::no_shift, 0 },
/* 16 bit zext */ { ARM::t2UXTH , 0, ARM_AM::no_shift, 0 } }
}
}
};
unsigned SrcBits = SrcVT.getSizeInBits();
unsigned DestBits = DestVT.getSizeInBits();
(void) DestBits;
assert((SrcBits < DestBits) && "can only extend to larger types");
assert((DestBits == 32 || DestBits == 16 || DestBits == 8) &&
"other sizes unimplemented");
assert((SrcBits == 16 || SrcBits == 8 || SrcBits == 1) &&
"other sizes unimplemented");
bool hasV6Ops = Subtarget->hasV6Ops();
unsigned Bitness = SrcBits / 8; // {1,8,16}=>{0,1,2}
assert((Bitness < 3) && "sanity-check table bounds");
bool isSingleInstr = isSingleInstrTbl[Bitness][isThumb2][hasV6Ops][isZExt];
const TargetRegisterClass *RC = RCTbl[isThumb2][isSingleInstr];
const InstructionTable *ITP = &IT[isSingleInstr][isThumb2][Bitness][isZExt];
unsigned Opc = ITP->Opc;
assert(ARM::KILL != Opc && "Invalid table entry");
unsigned hasS = ITP->hasS;
ARM_AM::ShiftOpc Shift = (ARM_AM::ShiftOpc) ITP->Shift;
assert(((Shift == ARM_AM::no_shift) == (Opc != ARM::MOVsi)) &&
"only MOVsi has shift operand addressing mode");
unsigned Imm = ITP->Imm;
// 16-bit Thumb instructions always set CPSR (unless they're in an IT block).
bool setsCPSR = &ARM::tGPRRegClass == RC;
unsigned LSLOpc = isThumb2 ? ARM::tLSLri : ARM::MOVsi;
unsigned ResultReg;
// MOVsi encodes shift and immediate in shift operand addressing mode.
// The following condition has the same value when emitting two
// instruction sequences: both are shifts.
bool ImmIsSO = (Shift != ARM_AM::no_shift);
// Either one or two instructions are emitted.
// They're always of the form:
// dst = in OP imm
// CPSR is set only by 16-bit Thumb instructions.
// Predicate, if any, is AL.
// S bit, if available, is always 0.
// When two are emitted the first's result will feed as the second's input,
// that value is then dead.
unsigned NumInstrsEmitted = isSingleInstr ? 1 : 2;
for (unsigned Instr = 0; Instr != NumInstrsEmitted; ++Instr) {
ResultReg = createResultReg(RC);
bool isLsl = (0 == Instr) && !isSingleInstr;
unsigned Opcode = isLsl ? LSLOpc : Opc;
ARM_AM::ShiftOpc ShiftAM = isLsl ? ARM_AM::lsl : Shift;
unsigned ImmEnc = ImmIsSO ? ARM_AM::getSORegOpc(ShiftAM, Imm) : Imm;
bool isKill = 1 == Instr;
MachineInstrBuilder MIB = BuildMI(
*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(Opcode), ResultReg);
if (setsCPSR)
MIB.addReg(ARM::CPSR, RegState::Define);
SrcReg = constrainOperandRegClass(TII.get(Opcode), SrcReg, 1 + setsCPSR);
MIB.addReg(SrcReg, isKill * RegState::Kill)
.addImm(ImmEnc)
.add(predOps(ARMCC::AL));
if (hasS)
MIB.add(condCodeOp());
// Second instruction consumes the first's result.
SrcReg = ResultReg;
}
return ResultReg;
}
bool ARMFastISel::SelectIntExt(const Instruction *I) {
// On ARM, in general, integer casts don't involve legal types; this code
// handles promotable integers.
Type *DestTy = I->getType();
Value *Src = I->getOperand(0);
Type *SrcTy = Src->getType();
bool isZExt = isa<ZExtInst>(I);
Register SrcReg = getRegForValue(Src);
if (!SrcReg) return false;
EVT SrcEVT, DestEVT;
SrcEVT = TLI.getValueType(DL, SrcTy, true);
DestEVT = TLI.getValueType(DL, DestTy, true);
if (!SrcEVT.isSimple()) return false;
if (!DestEVT.isSimple()) return false;
MVT SrcVT = SrcEVT.getSimpleVT();
MVT DestVT = DestEVT.getSimpleVT();
unsigned ResultReg = ARMEmitIntExt(SrcVT, SrcReg, DestVT, isZExt);
if (ResultReg == 0) return false;
updateValueMap(I, ResultReg);
return true;
}
bool ARMFastISel::SelectShift(const Instruction *I,
ARM_AM::ShiftOpc ShiftTy) {
// We handle thumb2 mode by target independent selector
// or SelectionDAG ISel.
if (isThumb2)
return false;
// Only handle i32 now.
EVT DestVT = TLI.getValueType(DL, I->getType(), true);
if (DestVT != MVT::i32)
return false;
unsigned Opc = ARM::MOVsr;
unsigned ShiftImm;
Value *Src2Value = I->getOperand(1);
if (const ConstantInt *CI = dyn_cast<ConstantInt>(Src2Value)) {
ShiftImm = CI->getZExtValue();
// Fall back to selection DAG isel if the shift amount
// is zero or greater than the width of the value type.
if (ShiftImm == 0 || ShiftImm >=32)
return false;
Opc = ARM::MOVsi;
}
Value *Src1Value = I->getOperand(0);
Register Reg1 = getRegForValue(Src1Value);
if (Reg1 == 0) return false;
unsigned Reg2 = 0;
if (Opc == ARM::MOVsr) {
Reg2 = getRegForValue(Src2Value);
if (Reg2 == 0) return false;
}
Register ResultReg = createResultReg(&ARM::GPRnopcRegClass);
if(ResultReg == 0) return false;
MachineInstrBuilder MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(Opc), ResultReg)
.addReg(Reg1);
if (Opc == ARM::MOVsi)
MIB.addImm(ARM_AM::getSORegOpc(ShiftTy, ShiftImm));
else if (Opc == ARM::MOVsr) {
MIB.addReg(Reg2);
MIB.addImm(ARM_AM::getSORegOpc(ShiftTy, 0));
}
AddOptionalDefs(MIB);
updateValueMap(I, ResultReg);
return true;
}
// TODO: SoftFP support.
bool ARMFastISel::fastSelectInstruction(const Instruction *I) {
switch (I->getOpcode()) {
case Instruction::Load:
return SelectLoad(I);
case Instruction::Store:
return SelectStore(I);
case Instruction::Br:
return SelectBranch(I);
case Instruction::IndirectBr:
return SelectIndirectBr(I);
case Instruction::ICmp:
case Instruction::FCmp:
return SelectCmp(I);
case Instruction::FPExt:
return SelectFPExt(I);
case Instruction::FPTrunc:
return SelectFPTrunc(I);
case Instruction::SIToFP:
return SelectIToFP(I, /*isSigned*/ true);
case Instruction::UIToFP:
return SelectIToFP(I, /*isSigned*/ false);
case Instruction::FPToSI:
return SelectFPToI(I, /*isSigned*/ true);
case Instruction::FPToUI:
return SelectFPToI(I, /*isSigned*/ false);
case Instruction::Add:
return SelectBinaryIntOp(I, ISD::ADD);
case Instruction::Or:
return SelectBinaryIntOp(I, ISD::OR);
case Instruction::Sub:
return SelectBinaryIntOp(I, ISD::SUB);
case Instruction::FAdd:
return SelectBinaryFPOp(I, ISD::FADD);
case Instruction::FSub:
return SelectBinaryFPOp(I, ISD::FSUB);
case Instruction::FMul:
return SelectBinaryFPOp(I, ISD::FMUL);
case Instruction::SDiv:
return SelectDiv(I, /*isSigned*/ true);
case Instruction::UDiv:
return SelectDiv(I, /*isSigned*/ false);
case Instruction::SRem:
return SelectRem(I, /*isSigned*/ true);
case Instruction::URem:
return SelectRem(I, /*isSigned*/ false);
case Instruction::Call:
if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(I))
return SelectIntrinsicCall(*II);
return SelectCall(I);
case Instruction::Select:
return SelectSelect(I);
case Instruction::Ret:
return SelectRet(I);
case Instruction::Trunc:
return SelectTrunc(I);
case Instruction::ZExt:
case Instruction::SExt:
return SelectIntExt(I);
case Instruction::Shl:
return SelectShift(I, ARM_AM::lsl);
case Instruction::LShr:
return SelectShift(I, ARM_AM::lsr);
case Instruction::AShr:
return SelectShift(I, ARM_AM::asr);
default: break;
}
return false;
}
// This table describes sign- and zero-extend instructions which can be
// folded into a preceding load. All of these extends have an immediate
// (sometimes a mask and sometimes a shift) that's applied after
// extension.
static const struct FoldableLoadExtendsStruct {
uint16_t Opc[2]; // ARM, Thumb.
uint8_t ExpectedImm;
uint8_t isZExt : 1;
uint8_t ExpectedVT : 7;
} FoldableLoadExtends[] = {
{ { ARM::SXTH, ARM::t2SXTH }, 0, 0, MVT::i16 },
{ { ARM::UXTH, ARM::t2UXTH }, 0, 1, MVT::i16 },
{ { ARM::ANDri, ARM::t2ANDri }, 255, 1, MVT::i8 },
{ { ARM::SXTB, ARM::t2SXTB }, 0, 0, MVT::i8 },
{ { ARM::UXTB, ARM::t2UXTB }, 0, 1, MVT::i8 }
};
/// 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
/// successful.
bool ARMFastISel::tryToFoldLoadIntoMI(MachineInstr *MI, unsigned OpNo,
const LoadInst *LI) {
// Verify we have a legal type before going any further.
MVT VT;
if (!isLoadTypeLegal(LI->getType(), VT))
return false;
// Combine load followed by zero- or sign-extend.
// ldrb r1, [r0] ldrb r1, [r0]
// uxtb r2, r1 =>
// mov r3, r2 mov r3, r1
if (MI->getNumOperands() < 3 || !MI->getOperand(2).isImm())
return false;
const uint64_t Imm = MI->getOperand(2).getImm();
bool Found = false;
bool isZExt;
for (const FoldableLoadExtendsStruct &FLE : FoldableLoadExtends) {
if (FLE.Opc[isThumb2] == MI->getOpcode() &&
(uint64_t)FLE.ExpectedImm == Imm &&
MVT((MVT::SimpleValueType)FLE.ExpectedVT) == VT) {
Found = true;
isZExt = FLE.isZExt;
}
}
if (!Found) return false;
// See if we can handle this address.
Address Addr;
if (!ARMComputeAddress(LI->getOperand(0), Addr)) return false;
Register ResultReg = MI->getOperand(0).getReg();
if (!ARMEmitLoad(VT, ResultReg, Addr, LI->getAlign(), isZExt, false))
return false;
MachineBasicBlock::iterator I(MI);
removeDeadCode(I, std::next(I));
return true;
}
unsigned ARMFastISel::ARMLowerPICELF(const GlobalValue *GV, MVT VT) {
bool UseGOT_PREL = !GV->isDSOLocal();
LLVMContext *Context = &MF->getFunction().getContext();
unsigned ARMPCLabelIndex = AFI->createPICLabelUId();
unsigned PCAdj = Subtarget->isThumb() ? 4 : 8;
ARMConstantPoolValue *CPV = ARMConstantPoolConstant::Create(
GV, ARMPCLabelIndex, ARMCP::CPValue, PCAdj,
UseGOT_PREL ? ARMCP::GOT_PREL : ARMCP::no_modifier,
/*AddCurrentAddress=*/UseGOT_PREL);
Align ConstAlign =
MF->getDataLayout().getPrefTypeAlign(PointerType::get(*Context, 0));
unsigned Idx = MF->getConstantPool()->getConstantPoolIndex(CPV, ConstAlign);
MachineMemOperand *CPMMO =
MF->getMachineMemOperand(MachinePointerInfo::getConstantPool(*MF),
MachineMemOperand::MOLoad, 4, Align(4));
Register TempReg = MF->getRegInfo().createVirtualRegister(&ARM::rGPRRegClass);
unsigned Opc = isThumb2 ? ARM::t2LDRpci : ARM::LDRcp;
MachineInstrBuilder MIB =
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(Opc), TempReg)
.addConstantPoolIndex(Idx)
.addMemOperand(CPMMO);
if (Opc == ARM::LDRcp)
MIB.addImm(0);
MIB.add(predOps(ARMCC::AL));
// Fix the address by adding pc.
Register DestReg = createResultReg(TLI.getRegClassFor(VT));
Opc = Subtarget->isThumb() ? ARM::tPICADD : UseGOT_PREL ? ARM::PICLDR
: ARM::PICADD;
DestReg = constrainOperandRegClass(TII.get(Opc), DestReg, 0);
MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD, TII.get(Opc), DestReg)
.addReg(TempReg)
.addImm(ARMPCLabelIndex);
if (!Subtarget->isThumb())
MIB.add(predOps(ARMCC::AL));
if (UseGOT_PREL && Subtarget->isThumb()) {
Register NewDestReg = createResultReg(TLI.getRegClassFor(VT));
MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(ARM::t2LDRi12), NewDestReg)
.addReg(DestReg)
.addImm(0);
DestReg = NewDestReg;
AddOptionalDefs(MIB);
}
return DestReg;
}
bool ARMFastISel::fastLowerArguments() {
if (!FuncInfo.CanLowerReturn)
return false;
const Function *F = FuncInfo.Fn;
if (F->isVarArg())
return false;
CallingConv::ID CC = F->getCallingConv();
switch (CC) {
default:
return false;
case CallingConv::Fast:
case CallingConv::C:
case CallingConv::ARM_AAPCS_VFP:
case CallingConv::ARM_AAPCS:
case CallingConv::ARM_APCS:
case CallingConv::Swift:
case CallingConv::SwiftTail:
break;
}
// Only handle simple cases. i.e. Up to 4 i8/i16/i32 scalar arguments
// which are passed in r0 - r3.
for (const Argument &Arg : F->args()) {
if (Arg.getArgNo() >= 4)
return false;
if (Arg.hasAttribute(Attribute::InReg) ||
Arg.hasAttribute(Attribute::StructRet) ||
Arg.hasAttribute(Attribute::SwiftSelf) ||
Arg.hasAttribute(Attribute::SwiftError) ||
Arg.hasAttribute(Attribute::ByVal))
return false;
Type *ArgTy = Arg.getType();
if (ArgTy->isStructTy() || ArgTy->isArrayTy() || ArgTy->isVectorTy())
return false;
EVT ArgVT = TLI.getValueType(DL, ArgTy);
if (!ArgVT.isSimple()) return false;
switch (ArgVT.getSimpleVT().SimpleTy) {
case MVT::i8:
case MVT::i16:
case MVT::i32:
break;
default:
return false;
}
}
static const MCPhysReg GPRArgRegs[] = {
ARM::R0, ARM::R1, ARM::R2, ARM::R3
};
const TargetRegisterClass *RC = &ARM::rGPRRegClass;
for (const Argument &Arg : F->args()) {
unsigned ArgNo = Arg.getArgNo();
unsigned SrcReg = GPRArgRegs[ArgNo];
Register DstReg = FuncInfo.MF->addLiveIn(SrcReg, RC);
// FIXME: Unfortunately it's necessary to emit a copy from the livein copy.
// Without this, EmitLiveInCopies may eliminate the livein if its only
// use is a bitcast (which isn't turned into an instruction).
Register ResultReg = createResultReg(RC);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(TargetOpcode::COPY),
ResultReg).addReg(DstReg, getKillRegState(true));
updateValueMap(&Arg, ResultReg);
}
return true;
}
namespace llvm {
FastISel *ARM::createFastISel(FunctionLoweringInfo &funcInfo,
const TargetLibraryInfo *libInfo) {
if (funcInfo.MF->getSubtarget<ARMSubtarget>().useFastISel())
return new ARMFastISel(funcInfo, libInfo);
return nullptr;
}
} // end namespace llvm