maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity
llvm-project/llvm/lib/Target/WebAssembly/WebAssemblyFastISel.cpp

1436 lines
42 KiB
C++
Raw Blame History

//===-- WebAssemblyFastISel.cpp - WebAssembly 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
//
//===----------------------------------------------------------------------===//
///
/// \file
/// This file defines the WebAssembly-specific support for the FastISel
/// class. Some of the target-specific code is generated by tablegen in the file
/// WebAssemblyGenFastISel.inc, which is #included here.
///
/// TODO: kill flags
///
//===----------------------------------------------------------------------===//
#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
#include "Utils/WebAssemblyTypeUtilities.h"
#include "Utils/WebAssemblyUtilities.h"
#include "WebAssembly.h"
#include "WebAssemblyMachineFunctionInfo.h"
#include "WebAssemblySubtarget.h"
#include "WebAssemblyTargetMachine.h"
#include "llvm/Analysis/BranchProbabilityInfo.h"
#include "llvm/CodeGen/FastISel.h"
#include "llvm/CodeGen/FunctionLoweringInfo.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/PatternMatch.h"
using namespace llvm;
using namespace PatternMatch;
#define DEBUG_TYPE "wasm-fastisel"
namespace {
class WebAssemblyFastISel final : public FastISel {
// All possible address modes.
class Address {
public:
using BaseKind = enum { RegBase, FrameIndexBase };
private:
BaseKind Kind = RegBase;
union {
unsigned Reg;
int FI;
} Base;
// Whether the base has been determined yet
bool IsBaseSet = false;
int64_t Offset = 0;
const GlobalValue *GV = nullptr;
public:
// Innocuous defaults for our address.
Address() { Base.Reg = 0; }
void setKind(BaseKind K) {
assert(!isSet() && "Can't change kind with non-zero base");
Kind = K;
}
BaseKind getKind() const { return Kind; }
bool isRegBase() const { return Kind == RegBase; }
bool isFIBase() const { return Kind == FrameIndexBase; }
void setReg(unsigned Reg) {
assert(isRegBase() && "Invalid base register access!");
assert(!IsBaseSet && "Base cannot be reset");
Base.Reg = Reg;
IsBaseSet = true;
}
unsigned getReg() const {
assert(isRegBase() && "Invalid base register access!");
return Base.Reg;
}
void setFI(unsigned FI) {
assert(isFIBase() && "Invalid base frame index access!");
assert(!IsBaseSet && "Base cannot be reset");
Base.FI = FI;
IsBaseSet = true;
}
unsigned getFI() const {
assert(isFIBase() && "Invalid base frame index access!");
return Base.FI;
}
void setOffset(int64_t NewOffset) {
assert(NewOffset >= 0 && "Offsets must be non-negative");
Offset = NewOffset;
}
int64_t getOffset() const { return Offset; }
void setGlobalValue(const GlobalValue *G) { GV = G; }
const GlobalValue *getGlobalValue() const { return GV; }
bool isSet() const { return IsBaseSet; }
};
/// Keep a pointer to the WebAssemblySubtarget around so that we can make the
/// right decision when generating code for different targets.
const WebAssemblySubtarget *Subtarget;
LLVMContext *Context;
private:
// Utility helper routines
MVT::SimpleValueType getSimpleType(Type *Ty) {
EVT VT = TLI.getValueType(DL, Ty, /*AllowUnknown=*/true);
return VT.isSimple() ? VT.getSimpleVT().SimpleTy
: MVT::INVALID_SIMPLE_VALUE_TYPE;
}
MVT::SimpleValueType getLegalType(MVT::SimpleValueType VT) {
switch (VT) {
case MVT::i1:
case MVT::i8:
case MVT::i16:
return MVT::i32;
case MVT::i32:
case MVT::i64:
case MVT::f32:
case MVT::f64:
return VT;
case MVT::funcref:
case MVT::externref:
if (Subtarget->hasReferenceTypes())
return VT;
break;
case MVT::f16:
return MVT::f32;
case MVT::v16i8:
case MVT::v8i16:
case MVT::v4i32:
case MVT::v4f32:
case MVT::v2i64:
case MVT::v2f64:
if (Subtarget->hasSIMD128())
return VT;
break;
default:
break;
}
return MVT::INVALID_SIMPLE_VALUE_TYPE;
}
bool computeAddress(const Value *Obj, Address &Addr);
void materializeLoadStoreOperands(Address &Addr);
void addLoadStoreOperands(const Address &Addr, const MachineInstrBuilder &MIB,
MachineMemOperand *MMO);
unsigned maskI1Value(unsigned Reg, const Value *V);
unsigned getRegForI1Value(const Value *V, const BasicBlock *BB, bool &Not);
unsigned zeroExtendToI32(unsigned Reg, const Value *V,
MVT::SimpleValueType From);
unsigned signExtendToI32(unsigned Reg, const Value *V,
MVT::SimpleValueType From);
unsigned zeroExtend(unsigned Reg, const Value *V, MVT::SimpleValueType From,
MVT::SimpleValueType To);
unsigned signExtend(unsigned Reg, const Value *V, MVT::SimpleValueType From,
MVT::SimpleValueType To);
unsigned getRegForUnsignedValue(const Value *V);
unsigned getRegForSignedValue(const Value *V);
unsigned getRegForPromotedValue(const Value *V, bool IsSigned);
unsigned notValue(unsigned Reg);
unsigned copyValue(unsigned Reg);
// Backend specific FastISel code.
unsigned fastMaterializeAlloca(const AllocaInst *AI) override;
unsigned fastMaterializeConstant(const Constant *C) override;
bool fastLowerArguments() override;
// Selection routines.
bool selectCall(const Instruction *I);
bool selectSelect(const Instruction *I);
bool selectTrunc(const Instruction *I);
bool selectZExt(const Instruction *I);
bool selectSExt(const Instruction *I);
bool selectICmp(const Instruction *I);
bool selectFCmp(const Instruction *I);
bool selectBitCast(const Instruction *I);
bool selectLoad(const Instruction *I);
bool selectStore(const Instruction *I);
bool selectBr(const Instruction *I);
bool selectRet(const Instruction *I);
bool selectUnreachable(const Instruction *I);
public:
// Backend specific FastISel code.
WebAssemblyFastISel(FunctionLoweringInfo &FuncInfo,
const TargetLibraryInfo *LibInfo)
: FastISel(FuncInfo, LibInfo, /*SkipTargetIndependentISel=*/true) {
Subtarget = &FuncInfo.MF->getSubtarget<WebAssemblySubtarget>();
Context = &FuncInfo.Fn->getContext();
}
bool fastSelectInstruction(const Instruction *I) override;
#include "WebAssemblyGenFastISel.inc"
};
} // end anonymous namespace
bool WebAssemblyFastISel::computeAddress(const Value *Obj, Address &Addr) {
const User *U = nullptr;
unsigned Opcode = Instruction::UserOp1;
if (const auto *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 auto *C = dyn_cast<ConstantExpr>(Obj)) {
Opcode = C->getOpcode();
U = C;
}
if (auto *Ty = dyn_cast<PointerType>(Obj->getType()))
if (Ty->getAddressSpace() > 255)
// Fast instruction selection doesn't support the special
// address spaces.
return false;
if (const auto *GV = dyn_cast<GlobalValue>(Obj)) {
if (TLI.isPositionIndependent())
return false;
if (Addr.getGlobalValue())
return false;
if (GV->isThreadLocal())
return false;
Addr.setGlobalValue(GV);
return true;
}
switch (Opcode) {
default:
break;
case Instruction::BitCast: {
// Look through bitcasts.
return computeAddress(U->getOperand(0), Addr);
}
case Instruction::IntToPtr: {
// Look past no-op inttoptrs.
if (TLI.getValueType(DL, U->getOperand(0)->getType()) ==
TLI.getPointerTy(DL))
return computeAddress(U->getOperand(0), Addr);
break;
}
case Instruction::PtrToInt: {
// Look past no-op ptrtoints.
if (TLI.getValueType(DL, U->getType()) == TLI.getPointerTy(DL))
return computeAddress(U->getOperand(0), Addr);
break;
}
case Instruction::GetElementPtr: {
Address SavedAddr = Addr;
uint64_t TmpOffset = Addr.getOffset();
// Non-inbounds geps can wrap; wasm's offsets can't.
if (!cast<GEPOperator>(U)->isInBounds())
goto unsupported_gep;
// Iterate through the GEP folding the constants into offsets where
// we can.
for (gep_type_iterator GTI = gep_type_begin(U), E = gep_type_end(U);
GTI != E; ++GTI) {
const Value *Op = GTI.getOperand();
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 = DL.getTypeAllocSize(GTI.getIndexedType());
for (;;) {
if (const auto *CI = dyn_cast<ConstantInt>(Op)) {
// Constant-offset addressing.
TmpOffset += CI->getSExtValue() * S;
break;
}
if (S == 1 && Addr.isRegBase() && Addr.getReg() == 0) {
// An unscaled add of a register. Set it as the new base.
Register Reg = getRegForValue(Op);
if (Reg == 0)
return false;
Addr.setReg(Reg);
break;
}
if (canFoldAddIntoGEP(U, Op)) {
// A compatible add with a constant operand. Fold the constant.
auto *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;
}
}
}
// Don't fold in negative offsets.
if (int64_t(TmpOffset) >= 0) {
// Try to grab the base operand now.
Addr.setOffset(TmpOffset);
if (computeAddress(U->getOperand(0), Addr))
return true;
}
// We failed, restore everything and try the other options.
Addr = SavedAddr;
unsupported_gep:
break;
}
case Instruction::Alloca: {
const auto *AI = cast<AllocaInst>(Obj);
DenseMap<const AllocaInst *, int>::iterator SI =
FuncInfo.StaticAllocaMap.find(AI);
if (SI != FuncInfo.StaticAllocaMap.end()) {
if (Addr.isSet()) {
return false;
}
Addr.setKind(Address::FrameIndexBase);
Addr.setFI(SI->second);
return true;
}
break;
}
case Instruction::Add: {
// Adds of constants are common and easy enough.
const Value *LHS = U->getOperand(0);
const Value *RHS = U->getOperand(1);
if (isa<ConstantInt>(LHS))
std::swap(LHS, RHS);
if (const auto *CI = dyn_cast<ConstantInt>(RHS)) {
uint64_t TmpOffset = Addr.getOffset() + CI->getSExtValue();
if (int64_t(TmpOffset) >= 0) {
Addr.setOffset(TmpOffset);
return computeAddress(LHS, Addr);
}
}
Address Backup = Addr;
if (computeAddress(LHS, Addr) && computeAddress(RHS, Addr))
return true;
Addr = Backup;
break;
}
case Instruction::Sub: {
// Subs of constants are common and easy enough.
const Value *LHS = U->getOperand(0);
const Value *RHS = U->getOperand(1);
if (const auto *CI = dyn_cast<ConstantInt>(RHS)) {
int64_t TmpOffset = Addr.getOffset() - CI->getSExtValue();
if (TmpOffset >= 0) {
Addr.setOffset(TmpOffset);
return computeAddress(LHS, Addr);
}
}
break;
}
}
if (Addr.isSet()) {
return false;
}
Register Reg = getRegForValue(Obj);
if (Reg == 0)
return false;
Addr.setReg(Reg);
return Addr.getReg() != 0;
}
void WebAssemblyFastISel::materializeLoadStoreOperands(Address &Addr) {
if (Addr.isRegBase()) {
unsigned Reg = Addr.getReg();
if (Reg == 0) {
Reg = createResultReg(Subtarget->hasAddr64() ? &WebAssembly::I64RegClass
: &WebAssembly::I32RegClass);
unsigned Opc = Subtarget->hasAddr64() ? WebAssembly::CONST_I64
: WebAssembly::CONST_I32;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc), Reg)
.addImm(0);
Addr.setReg(Reg);
}
}
}
void WebAssemblyFastISel::addLoadStoreOperands(const Address &Addr,
const MachineInstrBuilder &MIB,
MachineMemOperand *MMO) {
// Set the alignment operand (this is rewritten in SetP2AlignOperands).
// TODO: Disable SetP2AlignOperands for FastISel and just do it here.
MIB.addImm(0);
if (const GlobalValue *GV = Addr.getGlobalValue())
MIB.addGlobalAddress(GV, Addr.getOffset());
else
MIB.addImm(Addr.getOffset());
if (Addr.isRegBase())
MIB.addReg(Addr.getReg());
else
MIB.addFrameIndex(Addr.getFI());
MIB.addMemOperand(MMO);
}
unsigned WebAssemblyFastISel::maskI1Value(unsigned Reg, const Value *V) {
return zeroExtendToI32(Reg, V, MVT::i1);
}
unsigned WebAssemblyFastISel::getRegForI1Value(const Value *V,
const BasicBlock *BB,
bool &Not) {
if (const auto *ICmp = dyn_cast<ICmpInst>(V))
if (const ConstantInt *C = dyn_cast<ConstantInt>(ICmp->getOperand(1)))
if (ICmp->isEquality() && C->isZero() && C->getType()->isIntegerTy(32) &&
ICmp->getParent() == BB) {
Not = ICmp->isTrueWhenEqual();
return getRegForValue(ICmp->getOperand(0));
}
Not = false;
Register Reg = getRegForValue(V);
if (Reg == 0)
return 0;
return maskI1Value(Reg, V);
}
unsigned WebAssemblyFastISel::zeroExtendToI32(unsigned Reg, const Value *V,
MVT::SimpleValueType From) {
if (Reg == 0)
return 0;
switch (From) {
case MVT::i1:
// If the value is naturally an i1, we don't need to mask it. We only know
// if a value is naturally an i1 if it is definitely lowered by FastISel,
// not a DAG ISel fallback.
if (V != nullptr && isa<Argument>(V) && cast<Argument>(V)->hasZExtAttr())
return copyValue(Reg);
break;
case MVT::i8:
case MVT::i16:
break;
case MVT::i32:
return copyValue(Reg);
default:
return 0;
}
Register Imm = createResultReg(&WebAssembly::I32RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(WebAssembly::CONST_I32), Imm)
.addImm(~(~uint64_t(0) << MVT(From).getSizeInBits()));
Register Result = createResultReg(&WebAssembly::I32RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(WebAssembly::AND_I32), Result)
.addReg(Reg)
.addReg(Imm);
return Result;
}
unsigned WebAssemblyFastISel::signExtendToI32(unsigned Reg, const Value *V,
MVT::SimpleValueType From) {
if (Reg == 0)
return 0;
switch (From) {
case MVT::i1:
case MVT::i8:
case MVT::i16:
break;
case MVT::i32:
return copyValue(Reg);
default:
return 0;
}
Register Imm = createResultReg(&WebAssembly::I32RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(WebAssembly::CONST_I32), Imm)
.addImm(32 - MVT(From).getSizeInBits());
Register Left = createResultReg(&WebAssembly::I32RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(WebAssembly::SHL_I32), Left)
.addReg(Reg)
.addReg(Imm);
Register Right = createResultReg(&WebAssembly::I32RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(WebAssembly::SHR_S_I32), Right)
.addReg(Left)
.addReg(Imm);
return Right;
}
unsigned WebAssemblyFastISel::zeroExtend(unsigned Reg, const Value *V,
MVT::SimpleValueType From,
MVT::SimpleValueType To) {
if (To == MVT::i64) {
if (From == MVT::i64)
return copyValue(Reg);
Reg = zeroExtendToI32(Reg, V, From);
Register Result = createResultReg(&WebAssembly::I64RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(WebAssembly::I64_EXTEND_U_I32), Result)
.addReg(Reg);
return Result;
}
if (To == MVT::i32)
return zeroExtendToI32(Reg, V, From);
return 0;
}
unsigned WebAssemblyFastISel::signExtend(unsigned Reg, const Value *V,
MVT::SimpleValueType From,
MVT::SimpleValueType To) {
if (To == MVT::i64) {
if (From == MVT::i64)
return copyValue(Reg);
Reg = signExtendToI32(Reg, V, From);
Register Result = createResultReg(&WebAssembly::I64RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(WebAssembly::I64_EXTEND_S_I32), Result)
.addReg(Reg);
return Result;
}
if (To == MVT::i32)
return signExtendToI32(Reg, V, From);
return 0;
}
unsigned WebAssemblyFastISel::getRegForUnsignedValue(const Value *V) {
MVT::SimpleValueType From = getSimpleType(V->getType());
MVT::SimpleValueType To = getLegalType(From);
Register VReg = getRegForValue(V);
if (VReg == 0)
return 0;
return zeroExtend(VReg, V, From, To);
}
unsigned WebAssemblyFastISel::getRegForSignedValue(const Value *V) {
MVT::SimpleValueType From = getSimpleType(V->getType());
MVT::SimpleValueType To = getLegalType(From);
Register VReg = getRegForValue(V);
if (VReg == 0)
return 0;
return signExtend(VReg, V, From, To);
}
unsigned WebAssemblyFastISel::getRegForPromotedValue(const Value *V,
bool IsSigned) {
return IsSigned ? getRegForSignedValue(V) : getRegForUnsignedValue(V);
}
unsigned WebAssemblyFastISel::notValue(unsigned Reg) {
assert(MRI.getRegClass(Reg) == &WebAssembly::I32RegClass);
Register NotReg = createResultReg(&WebAssembly::I32RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(WebAssembly::EQZ_I32), NotReg)
.addReg(Reg);
return NotReg;
}
unsigned WebAssemblyFastISel::copyValue(unsigned Reg) {
Register ResultReg = createResultReg(MRI.getRegClass(Reg));
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(WebAssembly::COPY),
ResultReg)
.addReg(Reg);
return ResultReg;
}
unsigned WebAssemblyFastISel::fastMaterializeAlloca(const AllocaInst *AI) {
DenseMap<const AllocaInst *, int>::iterator SI =
FuncInfo.StaticAllocaMap.find(AI);
if (SI != FuncInfo.StaticAllocaMap.end()) {
Register ResultReg =
createResultReg(Subtarget->hasAddr64() ? &WebAssembly::I64RegClass
: &WebAssembly::I32RegClass);
unsigned Opc =
Subtarget->hasAddr64() ? WebAssembly::COPY_I64 : WebAssembly::COPY_I32;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc), ResultReg)
.addFrameIndex(SI->second);
return ResultReg;
}
return 0;
}
unsigned WebAssemblyFastISel::fastMaterializeConstant(const Constant *C) {
if (const GlobalValue *GV = dyn_cast<GlobalValue>(C)) {
if (TLI.isPositionIndependent())
return 0;
if (GV->isThreadLocal())
return 0;
Register ResultReg =
createResultReg(Subtarget->hasAddr64() ? &WebAssembly::I64RegClass
: &WebAssembly::I32RegClass);
unsigned Opc = Subtarget->hasAddr64() ? WebAssembly::CONST_I64
: WebAssembly::CONST_I32;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc), ResultReg)
.addGlobalAddress(GV);
return ResultReg;
}
// Let target-independent code handle it.
return 0;
}
bool WebAssemblyFastISel::fastLowerArguments() {
if (!FuncInfo.CanLowerReturn)
return false;
const Function *F = FuncInfo.Fn;
if (F->isVarArg())
return false;
if (FuncInfo.Fn->getCallingConv() == CallingConv::Swift)
return false;
unsigned I = 0;
for (auto const &Arg : F->args()) {
const AttributeList &Attrs = F->getAttributes();
if (Attrs.hasParamAttr(I, Attribute::ByVal) ||
Attrs.hasParamAttr(I, Attribute::SwiftSelf) ||
Attrs.hasParamAttr(I, Attribute::SwiftError) ||
Attrs.hasParamAttr(I, Attribute::InAlloca) ||
Attrs.hasParamAttr(I, Attribute::Nest))
return false;
Type *ArgTy = Arg.getType();
if (ArgTy->isStructTy() || ArgTy->isArrayTy())
return false;
if (!Subtarget->hasSIMD128() && ArgTy->isVectorTy())
return false;
unsigned Opc;
const TargetRegisterClass *RC;
switch (getSimpleType(ArgTy)) {
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
Opc = WebAssembly::ARGUMENT_i32;
RC = &WebAssembly::I32RegClass;
break;
case MVT::i64:
Opc = WebAssembly::ARGUMENT_i64;
RC = &WebAssembly::I64RegClass;
break;
case MVT::f32:
Opc = WebAssembly::ARGUMENT_f32;
RC = &WebAssembly::F32RegClass;
break;
case MVT::f64:
Opc = WebAssembly::ARGUMENT_f64;
RC = &WebAssembly::F64RegClass;
break;
case MVT::v16i8:
Opc = WebAssembly::ARGUMENT_v16i8;
RC = &WebAssembly::V128RegClass;
break;
case MVT::v8i16:
Opc = WebAssembly::ARGUMENT_v8i16;
RC = &WebAssembly::V128RegClass;
break;
case MVT::v4i32:
Opc = WebAssembly::ARGUMENT_v4i32;
RC = &WebAssembly::V128RegClass;
break;
case MVT::v2i64:
Opc = WebAssembly::ARGUMENT_v2i64;
RC = &WebAssembly::V128RegClass;
break;
case MVT::v4f32:
Opc = WebAssembly::ARGUMENT_v4f32;
RC = &WebAssembly::V128RegClass;
break;
case MVT::v2f64:
Opc = WebAssembly::ARGUMENT_v2f64;
RC = &WebAssembly::V128RegClass;
break;
case MVT::funcref:
Opc = WebAssembly::ARGUMENT_funcref;
RC = &WebAssembly::FUNCREFRegClass;
break;
case MVT::externref:
Opc = WebAssembly::ARGUMENT_externref;
RC = &WebAssembly::EXTERNREFRegClass;
break;
default:
return false;
}
Register ResultReg = createResultReg(RC);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc), ResultReg)
.addImm(I);
updateValueMap(&Arg, ResultReg);
++I;
}
MRI.addLiveIn(WebAssembly::ARGUMENTS);
auto *MFI = MF->getInfo<WebAssemblyFunctionInfo>();
for (auto const &Arg : F->args()) {
MVT::SimpleValueType ArgTy = getLegalType(getSimpleType(Arg.getType()));
if (ArgTy == MVT::INVALID_SIMPLE_VALUE_TYPE) {
MFI->clearParamsAndResults();
return false;
}
MFI->addParam(ArgTy);
}
if (!F->getReturnType()->isVoidTy()) {
MVT::SimpleValueType RetTy =
getLegalType(getSimpleType(F->getReturnType()));
if (RetTy == MVT::INVALID_SIMPLE_VALUE_TYPE) {
MFI->clearParamsAndResults();
return false;
}
MFI->addResult(RetTy);
}
return true;
}
bool WebAssemblyFastISel::selectCall(const Instruction *I) {
const auto *Call = cast<CallInst>(I);
// TODO: Support tail calls in FastISel
if (Call->isMustTailCall() || Call->isInlineAsm() ||
Call->getFunctionType()->isVarArg())
return false;
Function *Func = Call->getCalledFunction();
if (Func && Func->isIntrinsic())
return false;
if (Call->getCallingConv() == CallingConv::Swift)
return false;
bool IsDirect = Func != nullptr;
if (!IsDirect && isa<ConstantExpr>(Call->getCalledOperand()))
return false;
FunctionType *FuncTy = Call->getFunctionType();
unsigned Opc = IsDirect ? WebAssembly::CALL : WebAssembly::CALL_INDIRECT;
bool IsVoid = FuncTy->getReturnType()->isVoidTy();
unsigned ResultReg;
if (!IsVoid) {
if (!Subtarget->hasSIMD128() && Call->getType()->isVectorTy())
return false;
MVT::SimpleValueType RetTy = getSimpleType(Call->getType());
switch (RetTy) {
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
ResultReg = createResultReg(&WebAssembly::I32RegClass);
break;
case MVT::i64:
ResultReg = createResultReg(&WebAssembly::I64RegClass);
break;
case MVT::f32:
ResultReg = createResultReg(&WebAssembly::F32RegClass);
break;
case MVT::f64:
ResultReg = createResultReg(&WebAssembly::F64RegClass);
break;
case MVT::v16i8:
ResultReg = createResultReg(&WebAssembly::V128RegClass);
break;
case MVT::v8i16:
ResultReg = createResultReg(&WebAssembly::V128RegClass);
break;
case MVT::v4i32:
ResultReg = createResultReg(&WebAssembly::V128RegClass);
break;
case MVT::v2i64:
ResultReg = createResultReg(&WebAssembly::V128RegClass);
break;
case MVT::v4f32:
ResultReg = createResultReg(&WebAssembly::V128RegClass);
break;
case MVT::v2f64:
ResultReg = createResultReg(&WebAssembly::V128RegClass);
break;
case MVT::funcref:
ResultReg = createResultReg(&WebAssembly::FUNCREFRegClass);
break;
case MVT::externref:
ResultReg = createResultReg(&WebAssembly::EXTERNREFRegClass);
break;
default:
return false;
}
}
SmallVector<unsigned, 8> Args;
for (unsigned I = 0, E = Call->arg_size(); I < E; ++I) {
Value *V = Call->getArgOperand(I);
MVT::SimpleValueType ArgTy = getSimpleType(V->getType());
if (ArgTy == MVT::INVALID_SIMPLE_VALUE_TYPE)
return false;
const AttributeList &Attrs = Call->getAttributes();
if (Attrs.hasParamAttr(I, Attribute::ByVal) ||
Attrs.hasParamAttr(I, Attribute::SwiftSelf) ||
Attrs.hasParamAttr(I, Attribute::SwiftError) ||
Attrs.hasParamAttr(I, Attribute::InAlloca) ||
Attrs.hasParamAttr(I, Attribute::Nest))
return false;
unsigned Reg;
if (Attrs.hasParamAttr(I, Attribute::SExt))
Reg = getRegForSignedValue(V);
else if (Attrs.hasParamAttr(I, Attribute::ZExt))
Reg = getRegForUnsignedValue(V);
else
Reg = getRegForValue(V);
if (Reg == 0)
return false;
Args.push_back(Reg);
}
unsigned CalleeReg = 0;
if (!IsDirect) {
CalleeReg = getRegForValue(Call->getCalledOperand());
if (!CalleeReg)
return false;
}
auto MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc));
if (!IsVoid)
MIB.addReg(ResultReg, RegState::Define);
if (IsDirect) {
MIB.addGlobalAddress(Func);
} else {
// Placeholder for the type index.
MIB.addImm(0);
// The table into which this call_indirect indexes.
MCSymbolWasm *Table = WebAssembly::getOrCreateFunctionTableSymbol(
MF->getMMI().getContext(), Subtarget);
if (Subtarget->hasReferenceTypes()) {
MIB.addSym(Table);
} else {
// Otherwise for the MVP there is at most one table whose number is 0, but
// we can't write a table symbol or issue relocations. Instead we just
// ensure the table is live.
Table->setNoStrip();
MIB.addImm(0);
}
// See if we must truncate the function pointer.
// CALL_INDIRECT takes an i32, but in wasm64 we represent function pointers
// as 64-bit for uniformity with other pointer types.
// See also: WebAssemblyISelLowering.cpp: LowerCallResults
if (Subtarget->hasAddr64()) {
auto Wrap = BuildMI(*FuncInfo.MBB, std::prev(FuncInfo.InsertPt), DbgLoc,
TII.get(WebAssembly::I32_WRAP_I64));
Register Reg32 = createResultReg(&WebAssembly::I32RegClass);
Wrap.addReg(Reg32, RegState::Define);
Wrap.addReg(CalleeReg);
CalleeReg = Reg32;
}
}
for (unsigned ArgReg : Args)
MIB.addReg(ArgReg);
if (!IsDirect)
MIB.addReg(CalleeReg);
if (!IsVoid)
updateValueMap(Call, ResultReg);
return true;
}
bool WebAssemblyFastISel::selectSelect(const Instruction *I) {
const auto *Select = cast<SelectInst>(I);
bool Not;
unsigned CondReg =
getRegForI1Value(Select->getCondition(), I->getParent(), Not);
if (CondReg == 0)
return false;
Register TrueReg = getRegForValue(Select->getTrueValue());
if (TrueReg == 0)
return false;
Register FalseReg = getRegForValue(Select->getFalseValue());
if (FalseReg == 0)
return false;
if (Not)
std::swap(TrueReg, FalseReg);
unsigned Opc;
const TargetRegisterClass *RC;
switch (getSimpleType(Select->getType())) {
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
Opc = WebAssembly::SELECT_I32;
RC = &WebAssembly::I32RegClass;
break;
case MVT::i64:
Opc = WebAssembly::SELECT_I64;
RC = &WebAssembly::I64RegClass;
break;
case MVT::f32:
Opc = WebAssembly::SELECT_F32;
RC = &WebAssembly::F32RegClass;
break;
case MVT::f64:
Opc = WebAssembly::SELECT_F64;
RC = &WebAssembly::F64RegClass;
break;
case MVT::funcref:
Opc = WebAssembly::SELECT_FUNCREF;
RC = &WebAssembly::FUNCREFRegClass;
break;
case MVT::externref:
Opc = WebAssembly::SELECT_EXTERNREF;
RC = &WebAssembly::EXTERNREFRegClass;
break;
default:
return false;
}
Register ResultReg = createResultReg(RC);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc), ResultReg)
.addReg(TrueReg)
.addReg(FalseReg)
.addReg(CondReg);
updateValueMap(Select, ResultReg);
return true;
}
bool WebAssemblyFastISel::selectTrunc(const Instruction *I) {
const auto *Trunc = cast<TruncInst>(I);
Register Reg = getRegForValue(Trunc->getOperand(0));
if (Reg == 0)
return false;
if (Trunc->getOperand(0)->getType()->isIntegerTy(64)) {
Register Result = createResultReg(&WebAssembly::I32RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(WebAssembly::I32_WRAP_I64), Result)
.addReg(Reg);
Reg = Result;
}
updateValueMap(Trunc, Reg);
return true;
}
bool WebAssemblyFastISel::selectZExt(const Instruction *I) {
const auto *ZExt = cast<ZExtInst>(I);
const Value *Op = ZExt->getOperand(0);
MVT::SimpleValueType From = getSimpleType(Op->getType());
MVT::SimpleValueType To = getLegalType(getSimpleType(ZExt->getType()));
Register In = getRegForValue(Op);
if (In == 0)
return false;
unsigned Reg = zeroExtend(In, Op, From, To);
if (Reg == 0)
return false;
updateValueMap(ZExt, Reg);
return true;
}
bool WebAssemblyFastISel::selectSExt(const Instruction *I) {
const auto *SExt = cast<SExtInst>(I);
const Value *Op = SExt->getOperand(0);
MVT::SimpleValueType From = getSimpleType(Op->getType());
MVT::SimpleValueType To = getLegalType(getSimpleType(SExt->getType()));
Register In = getRegForValue(Op);
if (In == 0)
return false;
unsigned Reg = signExtend(In, Op, From, To);
if (Reg == 0)
return false;
updateValueMap(SExt, Reg);
return true;
}
bool WebAssemblyFastISel::selectICmp(const Instruction *I) {
const auto *ICmp = cast<ICmpInst>(I);
bool I32 = getSimpleType(ICmp->getOperand(0)->getType()) != MVT::i64;
unsigned Opc;
bool IsSigned = false;
switch (ICmp->getPredicate()) {
case ICmpInst::ICMP_EQ:
Opc = I32 ? WebAssembly::EQ_I32 : WebAssembly::EQ_I64;
break;
case ICmpInst::ICMP_NE:
Opc = I32 ? WebAssembly::NE_I32 : WebAssembly::NE_I64;
break;
case ICmpInst::ICMP_UGT:
Opc = I32 ? WebAssembly::GT_U_I32 : WebAssembly::GT_U_I64;
break;
case ICmpInst::ICMP_UGE:
Opc = I32 ? WebAssembly::GE_U_I32 : WebAssembly::GE_U_I64;
break;
case ICmpInst::ICMP_ULT:
Opc = I32 ? WebAssembly::LT_U_I32 : WebAssembly::LT_U_I64;
break;
case ICmpInst::ICMP_ULE:
Opc = I32 ? WebAssembly::LE_U_I32 : WebAssembly::LE_U_I64;
break;
case ICmpInst::ICMP_SGT:
Opc = I32 ? WebAssembly::GT_S_I32 : WebAssembly::GT_S_I64;
IsSigned = true;
break;
case ICmpInst::ICMP_SGE:
Opc = I32 ? WebAssembly::GE_S_I32 : WebAssembly::GE_S_I64;
IsSigned = true;
break;
case ICmpInst::ICMP_SLT:
Opc = I32 ? WebAssembly::LT_S_I32 : WebAssembly::LT_S_I64;
IsSigned = true;
break;
case ICmpInst::ICMP_SLE:
Opc = I32 ? WebAssembly::LE_S_I32 : WebAssembly::LE_S_I64;
IsSigned = true;
break;
default:
return false;
}
unsigned LHS = getRegForPromotedValue(ICmp->getOperand(0), IsSigned);
if (LHS == 0)
return false;
unsigned RHS = getRegForPromotedValue(ICmp->getOperand(1), IsSigned);
if (RHS == 0)
return false;
Register ResultReg = createResultReg(&WebAssembly::I32RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc), ResultReg)
.addReg(LHS)
.addReg(RHS);
updateValueMap(ICmp, ResultReg);
return true;
}
bool WebAssemblyFastISel::selectFCmp(const Instruction *I) {
const auto *FCmp = cast<FCmpInst>(I);
Register LHS = getRegForValue(FCmp->getOperand(0));
if (LHS == 0)
return false;
Register RHS = getRegForValue(FCmp->getOperand(1));
if (RHS == 0)
return false;
bool F32 = getSimpleType(FCmp->getOperand(0)->getType()) != MVT::f64;
unsigned Opc;
bool Not = false;
switch (FCmp->getPredicate()) {
case FCmpInst::FCMP_OEQ:
Opc = F32 ? WebAssembly::EQ_F32 : WebAssembly::EQ_F64;
break;
case FCmpInst::FCMP_UNE:
Opc = F32 ? WebAssembly::NE_F32 : WebAssembly::NE_F64;
break;
case FCmpInst::FCMP_OGT:
Opc = F32 ? WebAssembly::GT_F32 : WebAssembly::GT_F64;
break;
case FCmpInst::FCMP_OGE:
Opc = F32 ? WebAssembly::GE_F32 : WebAssembly::GE_F64;
break;
case FCmpInst::FCMP_OLT:
Opc = F32 ? WebAssembly::LT_F32 : WebAssembly::LT_F64;
break;
case FCmpInst::FCMP_OLE:
Opc = F32 ? WebAssembly::LE_F32 : WebAssembly::LE_F64;
break;
case FCmpInst::FCMP_UGT:
Opc = F32 ? WebAssembly::LE_F32 : WebAssembly::LE_F64;
Not = true;
break;
case FCmpInst::FCMP_UGE:
Opc = F32 ? WebAssembly::LT_F32 : WebAssembly::LT_F64;
Not = true;
break;
case FCmpInst::FCMP_ULT:
Opc = F32 ? WebAssembly::GE_F32 : WebAssembly::GE_F64;
Not = true;
break;
case FCmpInst::FCMP_ULE:
Opc = F32 ? WebAssembly::GT_F32 : WebAssembly::GT_F64;
Not = true;
break;
default:
return false;
}
Register ResultReg = createResultReg(&WebAssembly::I32RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc), ResultReg)
.addReg(LHS)
.addReg(RHS);
if (Not)
ResultReg = notValue(ResultReg);
updateValueMap(FCmp, ResultReg);
return true;
}
bool WebAssemblyFastISel::selectBitCast(const Instruction *I) {
// Target-independent code can handle this, except it doesn't set the dead
// flag on the ARGUMENTS clobber, so we have to do that manually in order
// to satisfy code that expects this of isBitcast() instructions.
EVT VT = TLI.getValueType(DL, I->getOperand(0)->getType());
EVT RetVT = TLI.getValueType(DL, I->getType());
if (!VT.isSimple() || !RetVT.isSimple())
return false;
Register In = getRegForValue(I->getOperand(0));
if (In == 0)
return false;
if (VT == RetVT) {
// No-op bitcast.
updateValueMap(I, In);
return true;
}
Register Reg = fastEmit_ISD_BITCAST_r(VT.getSimpleVT(), RetVT.getSimpleVT(),
In);
if (!Reg)
return false;
MachineBasicBlock::iterator Iter = FuncInfo.InsertPt;
--Iter;
assert(Iter->isBitcast());
Iter->setPhysRegsDeadExcept(ArrayRef<Register>(), TRI);
updateValueMap(I, Reg);
return true;
}
bool WebAssemblyFastISel::selectLoad(const Instruction *I) {
const auto *Load = cast<LoadInst>(I);
if (Load->isAtomic())
return false;
if (!WebAssembly::isDefaultAddressSpace(Load->getPointerAddressSpace()))
return false;
if (!Subtarget->hasSIMD128() && Load->getType()->isVectorTy())
return false;
Address Addr;
if (!computeAddress(Load->getPointerOperand(), Addr))
return false;
// TODO: Fold a following sign-/zero-extend into the load instruction.
unsigned Opc;
const TargetRegisterClass *RC;
bool A64 = Subtarget->hasAddr64();
switch (getSimpleType(Load->getType())) {
case MVT::i1:
case MVT::i8:
Opc = A64 ? WebAssembly::LOAD8_U_I32_A64 : WebAssembly::LOAD8_U_I32_A32;
RC = &WebAssembly::I32RegClass;
break;
case MVT::i16:
Opc = A64 ? WebAssembly::LOAD16_U_I32_A64 : WebAssembly::LOAD16_U_I32_A32;
RC = &WebAssembly::I32RegClass;
break;
case MVT::i32:
Opc = A64 ? WebAssembly::LOAD_I32_A64 : WebAssembly::LOAD_I32_A32;
RC = &WebAssembly::I32RegClass;
break;
case MVT::i64:
Opc = A64 ? WebAssembly::LOAD_I64_A64 : WebAssembly::LOAD_I64_A32;
RC = &WebAssembly::I64RegClass;
break;
case MVT::f32:
Opc = A64 ? WebAssembly::LOAD_F32_A64 : WebAssembly::LOAD_F32_A32;
RC = &WebAssembly::F32RegClass;
break;
case MVT::f64:
Opc = A64 ? WebAssembly::LOAD_F64_A64 : WebAssembly::LOAD_F64_A32;
RC = &WebAssembly::F64RegClass;
break;
default:
return false;
}
materializeLoadStoreOperands(Addr);
Register ResultReg = createResultReg(RC);
auto MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc),
ResultReg);
addLoadStoreOperands(Addr, MIB, createMachineMemOperandFor(Load));
updateValueMap(Load, ResultReg);
return true;
}
bool WebAssemblyFastISel::selectStore(const Instruction *I) {
const auto *Store = cast<StoreInst>(I);
if (Store->isAtomic())
return false;
if (!WebAssembly::isDefaultAddressSpace(Store->getPointerAddressSpace()))
return false;
if (!Subtarget->hasSIMD128() &&
Store->getValueOperand()->getType()->isVectorTy())
return false;
Address Addr;
if (!computeAddress(Store->getPointerOperand(), Addr))
return false;
unsigned Opc;
bool VTIsi1 = false;
bool A64 = Subtarget->hasAddr64();
switch (getSimpleType(Store->getValueOperand()->getType())) {
case MVT::i1:
VTIsi1 = true;
LLVM_FALLTHROUGH;
case MVT::i8:
Opc = A64 ? WebAssembly::STORE8_I32_A64 : WebAssembly::STORE8_I32_A32;
break;
case MVT::i16:
Opc = A64 ? WebAssembly::STORE16_I32_A64 : WebAssembly::STORE16_I32_A32;
break;
case MVT::i32:
Opc = A64 ? WebAssembly::STORE_I32_A64 : WebAssembly::STORE_I32_A32;
break;
case MVT::i64:
Opc = A64 ? WebAssembly::STORE_I64_A64 : WebAssembly::STORE_I64_A32;
break;
case MVT::f32:
Opc = A64 ? WebAssembly::STORE_F32_A64 : WebAssembly::STORE_F32_A32;
break;
case MVT::f64:
Opc = A64 ? WebAssembly::STORE_F64_A64 : WebAssembly::STORE_F64_A32;
break;
default:
return false;
}
materializeLoadStoreOperands(Addr);
Register ValueReg = getRegForValue(Store->getValueOperand());
if (ValueReg == 0)
return false;
if (VTIsi1)
ValueReg = maskI1Value(ValueReg, Store->getValueOperand());
auto MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc));
addLoadStoreOperands(Addr, MIB, createMachineMemOperandFor(Store));
MIB.addReg(ValueReg);
return true;
}
bool WebAssemblyFastISel::selectBr(const Instruction *I) {
const auto *Br = cast<BranchInst>(I);
if (Br->isUnconditional()) {
MachineBasicBlock *MSucc = FuncInfo.MBBMap[Br->getSuccessor(0)];
fastEmitBranch(MSucc, Br->getDebugLoc());
return true;
}
MachineBasicBlock *TBB = FuncInfo.MBBMap[Br->getSuccessor(0)];
MachineBasicBlock *FBB = FuncInfo.MBBMap[Br->getSuccessor(1)];
bool Not;
unsigned CondReg = getRegForI1Value(Br->getCondition(), Br->getParent(), Not);
if (CondReg == 0)
return false;
unsigned Opc = WebAssembly::BR_IF;
if (Not)
Opc = WebAssembly::BR_UNLESS;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc))
.addMBB(TBB)
.addReg(CondReg);
finishCondBranch(Br->getParent(), TBB, FBB);
return true;
}
bool WebAssemblyFastISel::selectRet(const Instruction *I) {
if (!FuncInfo.CanLowerReturn)
return false;
const auto *Ret = cast<ReturnInst>(I);
if (Ret->getNumOperands() == 0) {
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(WebAssembly::RETURN));
return true;
}
// TODO: support multiple return in FastISel
if (Ret->getNumOperands() > 1)
return false;
Value *RV = Ret->getOperand(0);
if (!Subtarget->hasSIMD128() && RV->getType()->isVectorTy())
return false;
switch (getSimpleType(RV->getType())) {
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
case MVT::i64:
case MVT::f32:
case MVT::f64:
case MVT::v16i8:
case MVT::v8i16:
case MVT::v4i32:
case MVT::v2i64:
case MVT::v4f32:
case MVT::v2f64:
case MVT::funcref:
case MVT::externref:
break;
default:
return false;
}
unsigned Reg;
if (FuncInfo.Fn->getAttributes().hasRetAttr(Attribute::SExt))
Reg = getRegForSignedValue(RV);
else if (FuncInfo.Fn->getAttributes().hasRetAttr(Attribute::ZExt))
Reg = getRegForUnsignedValue(RV);
else
Reg = getRegForValue(RV);
if (Reg == 0)
return false;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(WebAssembly::RETURN))
.addReg(Reg);
return true;
}
bool WebAssemblyFastISel::selectUnreachable(const Instruction *I) {
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(WebAssembly::UNREACHABLE));
return true;
}
bool WebAssemblyFastISel::fastSelectInstruction(const Instruction *I) {
switch (I->getOpcode()) {
case Instruction::Call:
if (selectCall(I))
return true;
break;
case Instruction::Select:
return selectSelect(I);
case Instruction::Trunc:
return selectTrunc(I);
case Instruction::ZExt:
return selectZExt(I);
case Instruction::SExt:
return selectSExt(I);
case Instruction::ICmp:
return selectICmp(I);
case Instruction::FCmp:
return selectFCmp(I);
case Instruction::BitCast:
return selectBitCast(I);
case Instruction::Load:
return selectLoad(I);
case Instruction::Store:
return selectStore(I);
case Instruction::Br:
return selectBr(I);
case Instruction::Ret:
return selectRet(I);
case Instruction::Unreachable:
return selectUnreachable(I);
default:
break;
}
// Fall back to target-independent instruction selection.
return selectOperator(I, I->getOpcode());
}
FastISel *WebAssembly::createFastISel(FunctionLoweringInfo &FuncInfo,
const TargetLibraryInfo *LibInfo) {
return new WebAssemblyFastISel(FuncInfo, LibInfo);
}
Reference in New Issue View Git Blame Copy Permalink