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llvm-project/llvm/lib/Target/ARM/ARMFastISel.cpp

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//===-- ARMFastISel.cpp - ARM FastISel implementation ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// 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 "ARMRegisterInfo.h"
#include "ARMTargetMachine.h"
#include "ARMSubtarget.h"
#include "llvm/CallingConv.h"
#include "llvm/DerivedTypes.h"
#include "llvm/GlobalVariable.h"
#include "llvm/Instructions.h"
#include "llvm/IntrinsicInst.h"
#include "llvm/CodeGen/Analysis.h"
#include "llvm/CodeGen/FastISel.h"
#include "llvm/CodeGen/FunctionLoweringInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/Support/CallSite.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
static cl::opt<bool>
EnableARMFastISel("arm-fast-isel",
cl::desc("Turn on experimental ARM fast-isel support"),
cl::init(false), cl::Hidden);
namespace {
class ARMFastISel : 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;
const TargetMachine &TM;
const TargetInstrInfo &TII;
const TargetLowering &TLI;
const ARMFunctionInfo *AFI;
// Convenience variable to avoid checking all the time.
bool isThumb;
public:
explicit ARMFastISel(FunctionLoweringInfo &funcInfo)
: FastISel(funcInfo),
TM(funcInfo.MF->getTarget()),
TII(*TM.getInstrInfo()),
TLI(*TM.getTargetLowering()) {
Subtarget = &TM.getSubtarget<ARMSubtarget>();
AFI = funcInfo.MF->getInfo<ARMFunctionInfo>();
isThumb = AFI->isThumbFunction();
}
// Code from FastISel.cpp.
virtual unsigned FastEmitInst_(unsigned MachineInstOpcode,
const TargetRegisterClass *RC);
virtual unsigned FastEmitInst_r(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill);
virtual unsigned FastEmitInst_rr(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill,
unsigned Op1, bool Op1IsKill);
virtual unsigned FastEmitInst_ri(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill,
uint64_t Imm);
virtual unsigned FastEmitInst_rf(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill,
const ConstantFP *FPImm);
virtual unsigned FastEmitInst_i(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
uint64_t Imm);
virtual unsigned FastEmitInst_rri(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill,
unsigned Op1, bool Op1IsKill,
uint64_t Imm);
virtual unsigned FastEmitInst_extractsubreg(MVT RetVT,
unsigned Op0, bool Op0IsKill,
uint32_t Idx);
// Backend specific FastISel code.
virtual bool TargetSelectInstruction(const Instruction *I);
virtual unsigned TargetMaterializeConstant(const Constant *C);
#include "ARMGenFastISel.inc"
// Instruction selection routines.
virtual bool ARMSelectLoad(const Instruction *I);
virtual bool ARMSelectStore(const Instruction *I);
virtual bool ARMSelectBranch(const Instruction *I);
virtual bool ARMSelectCmp(const Instruction *I);
virtual bool ARMSelectFPExt(const Instruction *I);
virtual bool ARMSelectBinaryOp(const Instruction *I, unsigned ISDOpcode);
// Utility routines.
private:
bool isTypeLegal(const Type *Ty, EVT &VT);
bool isLoadTypeLegal(const Type *Ty, EVT &VT);
bool ARMEmitLoad(EVT VT, unsigned &ResultReg, unsigned Reg, int Offset);
bool ARMEmitStore(EVT VT, unsigned SrcReg, unsigned Reg, int Offset);
bool ARMLoadAlloca(const Instruction *I, EVT VT);
bool ARMStoreAlloca(const Instruction *I, unsigned SrcReg, EVT VT);
bool ARMComputeRegOffset(const Value *Obj, unsigned &Reg, int &Offset);
unsigned ARMMaterializeFP(const ConstantFP *CFP, EVT VT);
unsigned ARMMaterializeInt(const Constant *C);
bool DefinesOptionalPredicate(MachineInstr *MI, bool *CPSR);
const MachineInstrBuilder &AddOptionalDefs(const MachineInstrBuilder &MIB);
};
} // end anonymous namespace
// #include "ARMGenCallingConv.inc"
// 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) {
const TargetInstrDesc &TID = MI->getDesc();
if (!TID.hasOptionalDef())
return false;
// Look to see if our OptionalDef is defining CPSR or CCR.
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
const MachineOperand &MO = MI->getOperand(i);
if (!MO.isReg() || !MO.isDef()) continue;
if (MO.getReg() == ARM::CPSR)
*CPSR = true;
}
return true;
}
// If the machine is predicable go ahead and add the predicate operands, if
// it needs default CC operands add those.
const MachineInstrBuilder &
ARMFastISel::AddOptionalDefs(const MachineInstrBuilder &MIB) {
MachineInstr *MI = &*MIB;
// Do we use a predicate?
if (TII.isPredicable(MI))
AddDefaultPred(MIB);
// 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)) {
if (CPSR)
AddDefaultT1CC(MIB);
else
AddDefaultCC(MIB);
}
return MIB;
}
unsigned ARMFastISel::FastEmitInst_(unsigned MachineInstOpcode,
const TargetRegisterClass* RC) {
unsigned ResultReg = createResultReg(RC);
const TargetInstrDesc &II = TII.get(MachineInstOpcode);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg));
return ResultReg;
}
unsigned ARMFastISel::FastEmitInst_r(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill) {
unsigned ResultReg = createResultReg(RC);
const TargetInstrDesc &II = TII.get(MachineInstOpcode);
if (II.getNumDefs() >= 1)
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill));
else {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
.addReg(Op0, Op0IsKill * RegState::Kill));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(TargetOpcode::COPY), ResultReg)
.addReg(II.ImplicitDefs[0]));
}
return ResultReg;
}
unsigned ARMFastISel::FastEmitInst_rr(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill,
unsigned Op1, bool Op1IsKill) {
unsigned ResultReg = createResultReg(RC);
const TargetInstrDesc &II = TII.get(MachineInstOpcode);
if (II.getNumDefs() >= 1)
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
.addReg(Op1, Op1IsKill * RegState::Kill));
else {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
.addReg(Op0, Op0IsKill * RegState::Kill)
.addReg(Op1, Op1IsKill * RegState::Kill));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(TargetOpcode::COPY), ResultReg)
.addReg(II.ImplicitDefs[0]));
}
return ResultReg;
}
unsigned ARMFastISel::FastEmitInst_ri(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill,
uint64_t Imm) {
unsigned ResultReg = createResultReg(RC);
const TargetInstrDesc &II = TII.get(MachineInstOpcode);
if (II.getNumDefs() >= 1)
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
.addImm(Imm));
else {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
.addReg(Op0, Op0IsKill * RegState::Kill)
.addImm(Imm));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(TargetOpcode::COPY), ResultReg)
.addReg(II.ImplicitDefs[0]));
}
return ResultReg;
}
unsigned ARMFastISel::FastEmitInst_rf(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill,
const ConstantFP *FPImm) {
unsigned ResultReg = createResultReg(RC);
const TargetInstrDesc &II = TII.get(MachineInstOpcode);
if (II.getNumDefs() >= 1)
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
.addFPImm(FPImm));
else {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
.addReg(Op0, Op0IsKill * RegState::Kill)
.addFPImm(FPImm));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(TargetOpcode::COPY), ResultReg)
.addReg(II.ImplicitDefs[0]));
}
return ResultReg;
}
unsigned ARMFastISel::FastEmitInst_rri(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill,
unsigned Op1, bool Op1IsKill,
uint64_t Imm) {
unsigned ResultReg = createResultReg(RC);
const TargetInstrDesc &II = TII.get(MachineInstOpcode);
if (II.getNumDefs() >= 1)
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
.addReg(Op1, Op1IsKill * RegState::Kill)
.addImm(Imm));
else {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
.addReg(Op0, Op0IsKill * RegState::Kill)
.addReg(Op1, Op1IsKill * RegState::Kill)
.addImm(Imm));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(TargetOpcode::COPY), ResultReg)
.addReg(II.ImplicitDefs[0]));
}
return ResultReg;
}
unsigned ARMFastISel::FastEmitInst_i(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
uint64_t Imm) {
unsigned ResultReg = createResultReg(RC);
const TargetInstrDesc &II = TII.get(MachineInstOpcode);
if (II.getNumDefs() >= 1)
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
.addImm(Imm));
else {
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
.addImm(Imm));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(TargetOpcode::COPY), ResultReg)
.addReg(II.ImplicitDefs[0]));
}
return ResultReg;
}
unsigned ARMFastISel::FastEmitInst_extractsubreg(MVT RetVT,
unsigned Op0, bool Op0IsKill,
uint32_t Idx) {
unsigned ResultReg = createResultReg(TLI.getRegClassFor(RetVT));
assert(TargetRegisterInfo::isVirtualRegister(Op0) &&
"Cannot yet extract from physregs");
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt,
DL, TII.get(TargetOpcode::COPY), ResultReg)
.addReg(Op0, getKillRegState(Op0IsKill), Idx));
return ResultReg;
}
// 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, EVT VT) {
const APFloat Val = CFP->getValueAPF();
bool is64bit = VT.getSimpleVT().SimpleTy == 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)) {
unsigned Opc = is64bit ? ARM::FCONSTD : ARM::FCONSTS;
unsigned DestReg = createResultReg(TLI.getRegClassFor(VT));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(Opc),
DestReg)
.addFPImm(CFP));
return DestReg;
}
// No 64-bit at the moment.
if (is64bit) return 0;
// Load this from the constant pool.
unsigned DestReg = ARMMaterializeInt(cast<Constant>(CFP));
// If we have a floating point constant we expect it in a floating point
// register.
unsigned MoveReg = createResultReg(TLI.getRegClassFor(VT));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(ARM::VMOVRS), MoveReg)
.addReg(DestReg));
return MoveReg;
}
unsigned ARMFastISel::ARMMaterializeInt(const Constant *C) {
// MachineConstantPool wants an explicit alignment.
unsigned Align = TD.getPrefTypeAlignment(C->getType());
if (Align == 0) {
// TODO: Figure out if this is correct.
Align = TD.getTypeAllocSize(C->getType());
}
unsigned Idx = MCP.getConstantPoolIndex(C, Align);
unsigned DestReg = createResultReg(TLI.getRegClassFor(MVT::i32));
if (isThumb)
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(ARM::t2LDRpci))
.addReg(DestReg).addConstantPoolIndex(Idx));
else
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(ARM::LDRcp))
.addReg(DestReg).addConstantPoolIndex(Idx)
.addReg(0).addImm(0));
return DestReg;
}
unsigned ARMFastISel::TargetMaterializeConstant(const Constant *C) {
EVT VT = TLI.getValueType(C->getType(), true);
// Only handle simple types.
if (!VT.isSimple()) return 0;
if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C))
return ARMMaterializeFP(CFP, VT);
return ARMMaterializeInt(C);
}
bool ARMFastISel::isTypeLegal(const Type *Ty, EVT &VT) {
VT = TLI.getValueType(Ty, true);
// Only handle simple types.
if (VT == MVT::Other || !VT.isSimple()) return false;
// Handle all legal types, i.e. a register that will directly hold this
// value.
return TLI.isTypeLegal(VT);
}
bool ARMFastISel::isLoadTypeLegal(const Type *Ty, EVT &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::i8 || VT == MVT::i16)
return true;
return false;
}
// Computes the Reg+Offset to get to an object.
bool ARMFastISel::ARMComputeRegOffset(const Value *Obj, unsigned &Reg,
int &Offset) {
// Some boilerplate from the X86 FastISel.
const User *U = NULL;
unsigned Opcode = Instruction::UserOp1;
if (const Instruction *I = dyn_cast<Instruction>(Obj)) {
// Don't walk into other basic blocks; it's possible we haven't
// visited them yet, so the instructions may not yet be assigned
// virtual registers.
if (FuncInfo.MBBMap[I->getParent()] != FuncInfo.MBB)
return false;
Opcode = I->getOpcode();
U = I;
} else if (const ConstantExpr *C = dyn_cast<ConstantExpr>(Obj)) {
Opcode = C->getOpcode();
U = C;
}
if (const 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:
//errs() << "Failing Opcode is: " << *Op1 << "\n";
break;
case Instruction::Alloca: {
assert(false && "Alloca should have been handled earlier!");
return false;
}
}
if (const GlobalValue *GV = dyn_cast<GlobalValue>(Obj)) {
//errs() << "Failing GV is: " << GV << "\n";
(void)GV;
return false;
}
// Try to get this in a register if nothing else has worked.
Reg = getRegForValue(Obj);
if (Reg == 0) return false;
// Since the offset may be too large for the load instruction
// get the reg+offset into a register.
// TODO: Verify the additions work, otherwise we'll need to add the
// offset instead of 0 to the instructions and do all sorts of operand
// munging.
// TODO: Optimize this somewhat.
if (Offset != 0) {
ARMCC::CondCodes Pred = ARMCC::AL;
unsigned PredReg = 0;
if (!isThumb)
emitARMRegPlusImmediate(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
Reg, Reg, Offset, Pred, PredReg,
static_cast<const ARMBaseInstrInfo&>(TII));
else {
assert(AFI->isThumb2Function());
emitT2RegPlusImmediate(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
Reg, Reg, Offset, Pred, PredReg,
static_cast<const ARMBaseInstrInfo&>(TII));
}
}
return true;
}
bool ARMFastISel::ARMLoadAlloca(const Instruction *I, EVT VT) {
Value *Op0 = I->getOperand(0);
// Verify it's an alloca.
if (const AllocaInst *AI = dyn_cast<AllocaInst>(Op0)) {
DenseMap<const AllocaInst*, int>::iterator SI =
FuncInfo.StaticAllocaMap.find(AI);
if (SI != FuncInfo.StaticAllocaMap.end()) {
TargetRegisterClass* RC = TLI.getRegClassFor(VT);
unsigned ResultReg = createResultReg(RC);
TII.loadRegFromStackSlot(*FuncInfo.MBB, *FuncInfo.InsertPt,
ResultReg, SI->second, RC,
TM.getRegisterInfo());
UpdateValueMap(I, ResultReg);
return true;
}
}
return false;
}
bool ARMFastISel::ARMEmitLoad(EVT VT, unsigned &ResultReg,
unsigned Reg, int Offset) {
assert(VT.isSimple() && "Non-simple types are invalid here!");
unsigned Opc;
switch (VT.getSimpleVT().SimpleTy) {
default:
assert(false && "Trying to emit for an unhandled type!");
return false;
case MVT::i16:
Opc = isThumb ? ARM::tLDRH : ARM::LDRH;
VT = MVT::i32;
break;
case MVT::i8:
Opc = isThumb ? ARM::tLDRB : ARM::LDRB;
VT = MVT::i32;
break;
case MVT::i32:
Opc = isThumb ? ARM::tLDR : ARM::LDR;
break;
}
ResultReg = createResultReg(TLI.getRegClassFor(VT));
// TODO: Fix the Addressing modes so that these can share some code.
// Since this is a Thumb1 load this will work in Thumb1 or 2 mode.
if (isThumb)
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(Opc), ResultReg)
.addReg(Reg).addImm(Offset).addReg(0));
else
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(Opc), ResultReg)
.addReg(Reg).addReg(0).addImm(Offset));
return true;
}
bool ARMFastISel::ARMStoreAlloca(const Instruction *I, unsigned SrcReg, EVT VT){
Value *Op1 = I->getOperand(1);
// Verify it's an alloca.
if (const AllocaInst *AI = dyn_cast<AllocaInst>(Op1)) {
DenseMap<const AllocaInst*, int>::iterator SI =
FuncInfo.StaticAllocaMap.find(AI);
if (SI != FuncInfo.StaticAllocaMap.end()) {
TargetRegisterClass* RC = TLI.getRegClassFor(VT);
assert(SrcReg != 0 && "Nothing to store!");
TII.storeRegToStackSlot(*FuncInfo.MBB, *FuncInfo.InsertPt,
SrcReg, true /*isKill*/, SI->second, RC,
TM.getRegisterInfo());
return true;
}
}
return false;
}
bool ARMFastISel::ARMEmitStore(EVT VT, unsigned SrcReg,
unsigned DstReg, int Offset) {
unsigned StrOpc;
switch (VT.getSimpleVT().SimpleTy) {
default: return false;
case MVT::i1:
case MVT::i8: StrOpc = isThumb ? ARM::tSTRB : ARM::STRB; break;
case MVT::i16: StrOpc = isThumb ? ARM::tSTRH : ARM::STRH; break;
case MVT::i32: StrOpc = isThumb ? ARM::tSTR : ARM::STR; break;
case MVT::f32:
if (!Subtarget->hasVFP2()) return false;
StrOpc = ARM::VSTRS;
break;
case MVT::f64:
if (!Subtarget->hasVFP2()) return false;
StrOpc = ARM::VSTRD;
break;
}
if (isThumb)
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(StrOpc), SrcReg)
.addReg(DstReg).addImm(Offset).addReg(0));
else
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(StrOpc), SrcReg)
.addReg(DstReg).addReg(0).addImm(Offset));
return true;
}
bool ARMFastISel::ARMSelectStore(const Instruction *I) {
Value *Op0 = I->getOperand(0);
unsigned SrcReg = 0;
// Yay type legalization
EVT 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;
// If we're an alloca we know we have a frame index and can emit the store
// quickly.
if (ARMStoreAlloca(I, SrcReg, VT))
return true;
// Our register and offset with innocuous defaults.
unsigned Reg = 0;
int Offset = 0;
// See if we can handle this as Reg + Offset
if (!ARMComputeRegOffset(I->getOperand(1), Reg, Offset))
return false;
if (!ARMEmitStore(VT, SrcReg, Reg, Offset /* 0 */)) return false;
return false;
}
bool ARMFastISel::ARMSelectLoad(const Instruction *I) {
// Verify we have a legal type before going any further.
EVT VT;
if (!isLoadTypeLegal(I->getType(), VT))
return false;
// If we're an alloca we know we have a frame index and can emit the load
// directly in short order.
if (ARMLoadAlloca(I, VT))
return true;
// Our register and offset with innocuous defaults.
unsigned Reg = 0;
int Offset = 0;
// See if we can handle this as Reg + Offset
if (!ARMComputeRegOffset(I->getOperand(0), Reg, Offset))
return false;
unsigned ResultReg;
if (!ARMEmitLoad(VT, ResultReg, Reg, Offset /* 0 */)) return false;
UpdateValueMap(I, ResultReg);
return true;
}
bool ARMFastISel::ARMSelectBranch(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.
unsigned CondReg = getRegForValue(BI->getCondition());
if (CondReg == 0) return false;
unsigned CmpOpc = isThumb ? ARM::t2CMPrr : ARM::CMPrr;
unsigned BrOpc = isThumb ? ARM::t2Bcc : ARM::Bcc;
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(CmpOpc))
.addReg(CondReg).addReg(CondReg));
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(BrOpc))
.addMBB(TBB).addImm(ARMCC::NE).addReg(ARM::CPSR);
FastEmitBranch(FBB, DL);
FuncInfo.MBB->addSuccessor(TBB);
return true;
}
bool ARMFastISel::ARMSelectCmp(const Instruction *I) {
const CmpInst *CI = cast<CmpInst>(I);
EVT VT;
const Type *Ty = CI->getOperand(0)->getType();
if (!isTypeLegal(Ty, VT))
return false;
bool isFloat = (Ty->isDoubleTy() || Ty->isFloatTy());
if (isFloat && !Subtarget->hasVFP2())
return false;
unsigned CmpOpc;
switch (VT.getSimpleVT().SimpleTy) {
default: return false;
// TODO: Verify compares.
case MVT::f32:
CmpOpc = ARM::VCMPES;
break;
case MVT::f64:
CmpOpc = ARM::VCMPED;
break;
case MVT::i32:
CmpOpc = isThumb ? ARM::t2CMPrr : ARM::CMPrr;
break;
}
unsigned Arg1 = getRegForValue(CI->getOperand(0));
if (Arg1 == 0) return false;
unsigned Arg2 = getRegForValue(CI->getOperand(1));
if (Arg2 == 0) return false;
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(CmpOpc))
.addReg(Arg1).addReg(Arg2));
// For floating point we need to move the result to a register we can
// actually do something with.
if (isFloat)
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(ARM::FMSTAT)));
return true;
}
bool ARMFastISel::ARMSelectFPExt(const Instruction *I) {
// Make sure we have VFP and that we're extending float to double.
if (!Subtarget->hasVFP2()) return false;
Value *V = I->getOperand(0);
if (!I->getType()->isDoubleTy() ||
!V->getType()->isFloatTy()) return false;
unsigned Op = getRegForValue(V);
if (Op == 0) return false;
unsigned Result = createResultReg(ARM::DPRRegisterClass);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(ARM::VCVTDS), Result)
.addReg(Op));
UpdateValueMap(I, Result);
return true;
}
bool ARMFastISel::ARMSelectBinaryOp(const Instruction *I, unsigned ISDOpcode) {
EVT VT = TLI.getValueType(I->getType(), true);
// 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.
const Type *Ty = I->getType();
bool isFloat = (Ty->isDoubleTy() || Ty->isFloatTy());
if (isFloat && !Subtarget->hasVFP2())
return false;
unsigned Op1 = getRegForValue(I->getOperand(0));
if (Op1 == 0) return false;
unsigned Op2 = getRegForValue(I->getOperand(1));
if (Op2 == 0) return false;
unsigned Opc;
bool is64bit = VT.getSimpleVT().SimpleTy == MVT::f64 ||
VT.getSimpleVT().SimpleTy == 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;
}
unsigned ResultReg = createResultReg(TLI.getRegClassFor(VT));
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
TII.get(Opc), ResultReg)
.addReg(Op1).addReg(Op2));
return true;
}
// TODO: SoftFP support.
bool ARMFastISel::TargetSelectInstruction(const Instruction *I) {
// No Thumb-1 for now.
if (isThumb && !AFI->isThumb2Function()) return false;
switch (I->getOpcode()) {
case Instruction::Load:
return ARMSelectLoad(I);
case Instruction::Store:
return ARMSelectStore(I);
case Instruction::Br:
return ARMSelectBranch(I);
case Instruction::ICmp:
case Instruction::FCmp:
return ARMSelectCmp(I);
case Instruction::FPExt:
return ARMSelectFPExt(I);
case Instruction::FAdd:
return ARMSelectBinaryOp(I, ISD::FADD);
case Instruction::FSub:
return ARMSelectBinaryOp(I, ISD::FSUB);
case Instruction::FMul:
return ARMSelectBinaryOp(I, ISD::FMUL);
default: break;
}
return false;
}
namespace llvm {
llvm::FastISel *ARM::createFastISel(FunctionLoweringInfo &funcInfo) {
if (EnableARMFastISel) return new ARMFastISel(funcInfo);
return 0;
}
}
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