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|
//===- ExpandI64.cpp - Expand i64 and wider integer types -------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===------------------------------------------------------------------===//
//
// This pass expands and lowers all operations on integers i64 and wider
// into 32-bit operations that can be handled by JS in a natural way.
//
// 64-bit variables become pairs of 2 32-bit variables, for the low and
// high 32 bit chunks. This happens for both registers and function
// arguments. Function return values become a return of the low 32 bits
// and a store of the high 32-bits in tempRet0, a global helper variable.
// Larger values become more chunks of 32 bits. Currently we require that
// types be a multiple of 32 bits.
//
// Many operations then become simple pairs of operations, for example
// bitwise AND becomes and AND of each 32-bit chunk. More complex operations
// like addition are lowered into calls into library support code in
// Emscripten (i64Add for example).
//
//===------------------------------------------------------------------===//
#include "llvm/ADT/PostOrderIterator.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/Pass.h"
#include "llvm/Support/CFG.h"
#include "llvm/Transforms/NaCl.h"
#include "llvm/Transforms/Utils/Local.h"
#include <map>
#include "llvm/Support/raw_ostream.h"
#ifdef NDEBUG
#undef assert
#define assert(x) { if (!(x)) report_fatal_error(#x); }
#endif
using namespace llvm;
namespace {
typedef SmallVector<Value*, 2> ChunksVec;
typedef std::map<Value*, ChunksVec> SplitsMap;
typedef SmallVector<PHINode *, 8> PHIVec;
typedef SmallVector<Instruction *, 8> DeadVec;
// This is a ModulePass because the pass recreates functions in
// order to expand i64 arguments to pairs of i32s.
class ExpandI64 : public ModulePass {
bool Changed;
DataLayout *DL;
Module *TheModule;
SplitsMap Splits; // old illegal value to new insts
PHIVec Phis;
// If the function has an illegal return or argument, create a legal version
void ensureLegalFunc(Function *F);
// If a function is illegal, remove it
void removeIllegalFunc(Function *F);
// splits an illegal instruction into 32-bit chunks. We do
// not yet have the values yet, as they depend on other
// splits, so store the parts in Splits, for FinalizeInst.
bool splitInst(Instruction *I);
// For an illegal value, returns the split out chunks
// representing the low and high parts, that splitInst
// generated.
// The value can also be a constant, in which case we just
// split it, or a function argument, in which case we
// map to the proper legalized new arguments
ChunksVec getChunks(Value *V);
Function *Add, *Sub, *Mul, *SDiv, *UDiv, *SRem, *URem, *LShr, *AShr, *Shl, *GetHigh, *SetHigh, *FtoILow, *FtoIHigh, *DtoILow, *DtoIHigh, *SItoF, *UItoF, *SItoD, *UItoD, *BItoD, *BDtoILow, *BDtoIHigh;
void ensureFuncs();
unsigned getNumChunks(Type *T);
public:
static char ID;
ExpandI64() : ModulePass(ID) {
initializeExpandI64Pass(*PassRegistry::getPassRegistry());
Add = Sub = Mul = SDiv = UDiv = SRem = URem = LShr = AShr = Shl = GetHigh = SetHigh = NULL;
}
virtual bool runOnModule(Module &M);
virtual void getAnalysisUsage(AnalysisUsage &AU) const;
};
}
char ExpandI64::ID = 0;
INITIALIZE_PASS(ExpandI64, "expand-illegal-ints",
"Expand and lower illegal >i32 operations into 32-bit chunks",
false, false)
// Utilities
static bool isIllegal(Type *T) {
return T->isIntegerTy() && T->getIntegerBitWidth() > 32;
}
static FunctionType *getLegalizedFunctionType(FunctionType *FT) {
SmallVector<Type*, 0> ArgTypes; // XXX
int Num = FT->getNumParams();
for (int i = 0; i < Num; i++) {
Type *T = FT->getParamType(i);
if (!isIllegal(T)) {
ArgTypes.push_back(T);
} else {
Type *i32 = Type::getInt32Ty(FT->getContext());
ArgTypes.push_back(i32);
ArgTypes.push_back(i32);
}
}
Type *RT = FT->getReturnType();
Type *NewRT;
if (!isIllegal(RT)) {
NewRT = RT;
} else {
NewRT = Type::getInt32Ty(FT->getContext());
}
return FunctionType::get(NewRT, ArgTypes, false);
}
// Implementation of ExpandI64
static bool okToRemainIllegal(Function *F) {
StringRef Name = F->getName();
if (Name == "llvm.dbg.value") return true;
// XXX EMSCRIPTEN: These take an i64 immediate argument; since they're not
// real instructions, we don't need to legalize them.
if (Name == "llvm.lifetime.start") return true;
if (Name == "llvm.lifetime.end") return true;
if (Name == "llvm.invariant.start") return true;
if (Name == "llvm.invariant.end") return true;
return false;
}
unsigned ExpandI64::getNumChunks(Type *T) {
unsigned Num = DL->getTypeSizeInBits(T);
return (Num + 31) / 32;
}
static bool isLegalFunctionType(FunctionType *FT) {
if (isIllegal(FT->getReturnType())) {
return false;
}
int Num = FT->getNumParams();
for (int i = 0; i < Num; i++) {
if (isIllegal(FT->getParamType(i))) {
return false;
}
}
return true;
}
static bool isLegalInstruction(const Instruction *I) {
if (isIllegal(I->getType())) {
return false;
}
for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
if (isIllegal(I->getOperand(i)->getType())) {
return false;
}
}
return true;
}
// We can't use RecreateFunction because we need to handle
// function and argument attributes specially.
static Function *RecreateFunctionLegalized(Function *F, FunctionType *NewType) {
Function *NewFunc = Function::Create(NewType, F->getLinkage());
AttributeSet Attrs = F->getAttributes();
AttributeSet FnAttrs = Attrs.getFnAttributes();
// Legalizing the return value is done by storing part of the value into
// static storage. Subsequent analysis will see this as a memory access,
// so we can no longer claim to be readonly or readnone.
if (isIllegal(F->getReturnType())) {
FnAttrs = FnAttrs.removeAttribute(F->getContext(),
AttributeSet::FunctionIndex,
Attribute::ReadOnly);
FnAttrs = FnAttrs.removeAttribute(F->getContext(),
AttributeSet::FunctionIndex,
Attribute::ReadNone);
}
NewFunc->addAttributes(AttributeSet::FunctionIndex, FnAttrs);
NewFunc->addAttributes(AttributeSet::ReturnIndex, Attrs.getRetAttributes());
Function::arg_iterator AI = F->arg_begin();
for (unsigned i = 0, e = F->arg_size(), j = 0; i != e; ++i, ++j, ++AI) {
AttributeSet ArgAttrs = Attrs.getParamAttributes(i);
if (isIllegal(AI->getType())) {
++j;
} else {
NewFunc->addAttributes(j + 1, ArgAttrs);
}
}
F->getParent()->getFunctionList().insert(F, NewFunc);
NewFunc->takeName(F);
NewFunc->getBasicBlockList().splice(NewFunc->begin(),
F->getBasicBlockList());
F->replaceAllUsesWith(
ConstantExpr::getBitCast(NewFunc,
F->getFunctionType()->getPointerTo()));
return NewFunc;
}
void ExpandI64::ensureLegalFunc(Function *F) {
if (okToRemainIllegal(F)) return;
FunctionType *FT = F->getFunctionType();
if (isLegalFunctionType(FT)) return;
Changed = true;
Function *NF = RecreateFunctionLegalized(F, getLegalizedFunctionType(FT));
std::string Name = NF->getName();
if (strncmp(Name.c_str(), "llvm.", 5) == 0) {
// this is an intrinsic, and we are changing its signature, which will annoy LLVM, so rename
const size_t len = Name.size();
SmallString<256> NewName;
NewName.resize(len);
for (unsigned i = 0; i < len; i++) {
NewName[i] = Name[i] != '.' ? Name[i] : '_';
}
NF->setName(Twine(NewName));
}
// Move and update arguments
for (Function::arg_iterator Arg = F->arg_begin(), E = F->arg_end(), NewArg = NF->arg_begin();
Arg != E; ++Arg) {
if (Arg->getType() == NewArg->getType()) {
NewArg->takeName(Arg);
Arg->replaceAllUsesWith(NewArg);
NewArg++;
} else {
// This was legalized
ChunksVec &Chunks = Splits[&*Arg];
int Num = getNumChunks(Arg->getType());
assert(Num == 2);
for (int i = 0; i < Num; i++) {
Chunks.push_back(&*NewArg);
if (NewArg->hasName()) Chunks[i]->setName(NewArg->getName() + "$" + utostr(i));
NewArg++;
}
}
}
}
void ExpandI64::removeIllegalFunc(Function *F) {
if (okToRemainIllegal(F)) return;
FunctionType *FT = F->getFunctionType();
if (!isLegalFunctionType(FT)) {
F->eraseFromParent();
}
}
bool ExpandI64::splitInst(Instruction *I) {
Type *i32 = Type::getInt32Ty(I->getContext());
Type *i32P = i32->getPointerTo();
Type *i64 = Type::getInt64Ty(I->getContext());
Value *Zero = Constant::getNullValue(i32);
ChunksVec &Chunks = Splits[I];
switch (I->getOpcode()) {
case Instruction::SExt: {
ChunksVec InputChunks;
Value *Op = I->getOperand(0);
if (isIllegal(Op->getType())) {
InputChunks = getChunks(Op);
} else {
InputChunks.push_back(Op);
}
for (unsigned i = 0, e = InputChunks.size(); i != e; ++i) {
Value *Input = InputChunks[i];
Type *T = Input->getType();
Value *Chunk;
if (T->getIntegerBitWidth() < 32) {
Chunk = CopyDebug(new SExtInst(Input, i32, "", I), I);
} else {
assert(T->getIntegerBitWidth() == 32);
Chunk = Input;
}
Chunks.push_back(Chunk);
}
Instruction *Check = CopyDebug(new ICmpInst(I, ICmpInst::ICMP_SLT, Chunks.back(), Zero), I);
int Num = getNumChunks(I->getType());
for (int i = Chunks.size(); i < Num; i++) {
Instruction *High = CopyDebug(new SExtInst(Check, i32, "", I), I);
Chunks.push_back(High);
}
break;
}
case Instruction::PtrToInt:
case Instruction::ZExt: {
Value *Op = I->getOperand(0);
ChunksVec InputChunks;
if (I->getOpcode() == Instruction::PtrToInt) {
InputChunks.push_back(CopyDebug(new PtrToIntInst(Op, i32, "", I), I));
} else if (isIllegal(Op->getType())) {
InputChunks = getChunks(Op);
} else {
InputChunks.push_back(Op);
}
for (unsigned i = 0, e = InputChunks.size(); i != e; ++i) {
Value *Input = InputChunks[i];
Type *T = Input->getType();
Value *Chunk;
if (T->getIntegerBitWidth() < 32) {
Chunk = CopyDebug(new ZExtInst(Input, i32, "", I), I);
} else {
assert(T->getIntegerBitWidth() == 32);
Chunk = Input;
}
Chunks.push_back(Chunk);
}
int Num = getNumChunks(I->getType());
for (int i = Chunks.size(); i < Num; i++) {
Chunks.push_back(Zero);
}
break;
}
case Instruction::IntToPtr:
case Instruction::Trunc: {
unsigned Num = getNumChunks(I->getType());
unsigned NumBits = DL->getTypeSizeInBits(I->getType());
ChunksVec InputChunks = getChunks(I->getOperand(0));
for (unsigned i = 0; i < Num; i++) {
Value *Input = InputChunks[i];
Value *Chunk;
if (NumBits < 32) {
Chunk = CopyDebug(new TruncInst(Input, IntegerType::get(I->getContext(), NumBits), "", I), I);
NumBits = 0;
} else {
Chunk = Input;
NumBits -= 32;
}
if (I->getOpcode() == Instruction::IntToPtr) {
assert(i == 0);
Chunk = CopyDebug(new IntToPtrInst(Chunk, I->getType(), "", I), I);
}
Chunks.push_back(Chunk);
}
if (!isIllegal(I->getType())) {
assert(Chunks.size() == 1);
I->replaceAllUsesWith(Chunks[0]);
}
break;
}
case Instruction::Load: {
LoadInst *LI = cast<LoadInst>(I);
Instruction *AI = CopyDebug(new PtrToIntInst(LI->getPointerOperand(), i32, "", I), I);
int Num = getNumChunks(I->getType());
for (int i = 0; i < Num; i++) {
Instruction *Add = i == 0 ? AI : CopyDebug(BinaryOperator::Create(Instruction::Add, AI, ConstantInt::get(i32, 4*i), "", I), I);
Instruction *Ptr = CopyDebug(new IntToPtrInst(Add, i32P, "", I), I);
LoadInst *Chunk = new LoadInst(Ptr, "", I); CopyDebug(Chunk, I);
Chunk->setAlignment(std::min(4U, LI->getAlignment()));
Chunk->setVolatile(LI->isVolatile());
Chunk->setOrdering(LI->getOrdering());
Chunk->setSynchScope(LI->getSynchScope());
Chunks.push_back(Chunk);
}
break;
}
case Instruction::Store: {
StoreInst *SI = cast<StoreInst>(I);
Instruction *AI = CopyDebug(new PtrToIntInst(SI->getPointerOperand(), i32, "", I), I);
ChunksVec InputChunks = getChunks(SI->getValueOperand());
int Num = InputChunks.size();
for (int i = 0; i < Num; i++) {
Instruction *Add = i == 0 ? AI : CopyDebug(BinaryOperator::Create(Instruction::Add, AI, ConstantInt::get(i32, 4*i), "", I), I);
Instruction *Ptr = CopyDebug(new IntToPtrInst(Add, i32P, "", I), I);
StoreInst *Chunk = new StoreInst(InputChunks[i], Ptr, I);
Chunk->setAlignment(std::min(4U, SI->getAlignment()));
Chunk->setVolatile(SI->isVolatile());
Chunk->setOrdering(SI->getOrdering());
Chunk->setSynchScope(SI->getSynchScope());
CopyDebug(Chunk, I);
}
break;
}
case Instruction::Ret: {
assert(I->getOperand(0)->getType() == i64);
ChunksVec InputChunks = getChunks(I->getOperand(0));
ensureFuncs();
SmallVector<Value *, 1> Args;
Args.push_back(InputChunks[1]);
CopyDebug(CallInst::Create(SetHigh, Args, "", I), I);
CopyDebug(ReturnInst::Create(I->getContext(), InputChunks[0], I), I);
break;
}
case Instruction::Add:
case Instruction::Sub:
case Instruction::Mul:
case Instruction::SDiv:
case Instruction::UDiv:
case Instruction::SRem:
case Instruction::URem:
case Instruction::LShr:
case Instruction::AShr:
case Instruction::Shl: {
ChunksVec LeftChunks = getChunks(I->getOperand(0));
ChunksVec RightChunks = getChunks(I->getOperand(1));
unsigned Num = getNumChunks(I->getType());
if (Num == 2) {
ensureFuncs();
Value *Low = NULL, *High = NULL;
Function *F = NULL;
switch (I->getOpcode()) {
case Instruction::Add: F = Add; break;
case Instruction::Sub: F = Sub; break;
case Instruction::Mul: F = Mul; break;
case Instruction::SDiv: F = SDiv; break;
case Instruction::UDiv: F = UDiv; break;
case Instruction::SRem: F = SRem; break;
case Instruction::URem: F = URem; break;
case Instruction::AShr: F = AShr; break;
case Instruction::LShr: {
if (ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(1))) {
unsigned Shifts = CI->getZExtValue();
if (Shifts == 32) {
Low = LeftChunks[1];
High = Zero;
break;
}
}
F = LShr;
break;
}
case Instruction::Shl: {
if (ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(1))) {
const APInt &Shifts = CI->getValue();
if (Shifts == 32) {
Low = Zero;
High = LeftChunks[0];
break;
}
}
F = Shl;
break;
}
default: assert(0);
}
if (F) {
// use a library call, no special optimization was found
SmallVector<Value *, 4> Args;
Args.push_back(LeftChunks[0]);
Args.push_back(LeftChunks[1]);
Args.push_back(RightChunks[0]);
Args.push_back(RightChunks[1]);
Low = CopyDebug(CallInst::Create(F, Args, "", I), I);
High = CopyDebug(CallInst::Create(GetHigh, "", I), I);
}
Chunks.push_back(Low);
Chunks.push_back(High);
} else {
// more than 64 bits. handle simple shifts for lshr and shl
assert(I->getOpcode() == Instruction::LShr || I->getOpcode() == Instruction::Shl);
ConstantInt *CI = cast<ConstantInt>(I->getOperand(1));
unsigned Shifts = CI->getZExtValue();
Constant *Frac = ConstantInt::get(i32, Shifts % 32);
Constant *Comp = ConstantInt::get(i32, 32 - (Shifts % 32));
Instruction::BinaryOps Opcode, Reverse;
unsigned ShiftChunks, Dir;
if (I->getOpcode() == Instruction::Shl) {
Opcode = Instruction::Shl;
Reverse = Instruction::LShr;
ShiftChunks = -(Shifts/32);
Dir = -1;
} else if (I->getOpcode() == Instruction::LShr) {
Opcode = Instruction::LShr;
Reverse = Instruction::Shl;
ShiftChunks = Shifts/32;
Dir = 1;
} else {
errs() << *I << "\n";
assert(0);
}
for (unsigned i = 0; i < Num; i++) {
Value *L;
if (i + ShiftChunks < LeftChunks.size()) {
L = LeftChunks[i + ShiftChunks];
} else {
L = Zero;
}
Value *H;
if (i + ShiftChunks + Dir < LeftChunks.size()) {
H = LeftChunks[i + ShiftChunks + Dir];
} else {
H = Zero;
}
// shifted the fractional amount
if (Frac != Zero && L != Zero) {
L = CopyDebug(BinaryOperator::Create(Opcode, L, Frac, "", I), I);
}
// shifted the complement-fractional amount to the other side
if (Comp != Zero && H != Zero) {
H = CopyDebug(BinaryOperator::Create(Reverse, H, Comp, "", I), I);
}
// Or the parts together. Since we may have zero, try to fold it away.
if (Value *V = SimplifyBinOp(Instruction::Or, L, H, DL)) {
Chunks.push_back(V);
} else {
Chunks.push_back(CopyDebug(BinaryOperator::Create(Instruction::Or, L, H, "", I), I));
}
}
}
break;
}
case Instruction::ICmp: {
ICmpInst *CE = cast<ICmpInst>(I);
ICmpInst::Predicate Pred = CE->getPredicate();
ChunksVec LeftChunks = getChunks(I->getOperand(0));
ChunksVec RightChunks = getChunks(I->getOperand(1));
switch (Pred) {
case ICmpInst::ICMP_EQ:
case ICmpInst::ICMP_NE: {
ICmpInst::Predicate PartPred; // the predicate to use on each of the parts
llvm::Instruction::BinaryOps CombineOp; // the predicate to use to combine the subcomparisons
int Num = LeftChunks.size();
if (Pred == ICmpInst::ICMP_EQ) {
PartPred = ICmpInst::ICMP_EQ;
CombineOp = Instruction::And;
} else {
PartPred = ICmpInst::ICMP_NE;
CombineOp = Instruction::Or;
}
// first combine 0 and 1. then combine that with 2, etc.
Value *Combined = NULL;
for (int i = 0; i < Num; i++) {
Value *Cmp = CopyDebug(new ICmpInst(I, PartPred, LeftChunks[i], RightChunks[i]), I);
Combined = !Combined ? Cmp : CopyDebug(BinaryOperator::Create(CombineOp, Combined, Cmp, "", I), I);
}
I->replaceAllUsesWith(Combined);
break;
}
case ICmpInst::ICMP_ULT:
case ICmpInst::ICMP_SLT:
case ICmpInst::ICMP_UGT:
case ICmpInst::ICMP_SGT:
case ICmpInst::ICMP_ULE:
case ICmpInst::ICMP_SLE:
case ICmpInst::ICMP_UGE:
case ICmpInst::ICMP_SGE: {
assert(I->getOperand(0)->getType() == i64);
Instruction *A, *B, *C, *D, *Final;
ICmpInst::Predicate StrictPred = Pred;
ICmpInst::Predicate UnsignedPred = Pred;
switch (Pred) {
case ICmpInst::ICMP_ULE: StrictPred = ICmpInst::ICMP_ULT; break;
case ICmpInst::ICMP_UGE: StrictPred = ICmpInst::ICMP_UGT; break;
case ICmpInst::ICMP_SLE: StrictPred = ICmpInst::ICMP_SLT; UnsignedPred = ICmpInst::ICMP_ULE; break;
case ICmpInst::ICMP_SGE: StrictPred = ICmpInst::ICMP_SGT; UnsignedPred = ICmpInst::ICMP_UGE; break;
case ICmpInst::ICMP_SLT: UnsignedPred = ICmpInst::ICMP_ULT; break;
case ICmpInst::ICMP_SGT: UnsignedPred = ICmpInst::ICMP_UGT; break;
case ICmpInst::ICMP_ULT: break;
case ICmpInst::ICMP_UGT: break;
default: assert(0);
}
A = CopyDebug(new ICmpInst(I, StrictPred, LeftChunks[1], RightChunks[1]), I);
B = CopyDebug(new ICmpInst(I, ICmpInst::ICMP_EQ, LeftChunks[1], RightChunks[1]), I);
C = CopyDebug(new ICmpInst(I, UnsignedPred, LeftChunks[0], RightChunks[0]), I);
D = CopyDebug(BinaryOperator::Create(Instruction::And, B, C, "", I), I);
Final = CopyDebug(BinaryOperator::Create(Instruction::Or, A, D, "", I), I);
I->replaceAllUsesWith(Final);
break;
}
default: assert(0);
}
break;
}
case Instruction::Select: {
SelectInst *SI = cast<SelectInst>(I);
Value *Cond = SI->getCondition();
ChunksVec TrueChunks = getChunks(SI->getTrueValue());
ChunksVec FalseChunks = getChunks(SI->getFalseValue());
unsigned Num = getNumChunks(I->getType());
for (unsigned i = 0; i < Num; i++) {
Instruction *Part = CopyDebug(SelectInst::Create(Cond, TrueChunks[i], FalseChunks[i], "", I), I);
Chunks.push_back(Part);
}
break;
}
case Instruction::PHI: {
PHINode *Parent = cast<PHINode>(I);
int Num = getNumChunks(I->getType());
int PhiNum = Parent->getNumIncomingValues();
for (int i = 0; i < Num; i++) {
Instruction *P = CopyDebug(PHINode::Create(i32, PhiNum, "", I), I);
Chunks.push_back(P);
}
// PHI node operands may not be translated yet; we'll handle them at the end.
Phis.push_back(Parent);
break;
}
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
BinaryOperator *BO = cast<BinaryOperator>(I);
ChunksVec LeftChunks = getChunks(BO->getOperand(0));
ChunksVec RightChunks = getChunks(BO->getOperand(1));
int Num = getNumChunks(BO->getType());
for (int i = 0; i < Num; i++) {
// If there's a constant operand, it's likely enough that one of the
// chunks will be a trivial operation, so it's worth calling
// SimplifyBinOp here.
if (Value *V = SimplifyBinOp(BO->getOpcode(), LeftChunks[i], RightChunks[i], DL)) {
Chunks.push_back(V);
} else {
Chunks.push_back(CopyDebug(BinaryOperator::Create(BO->getOpcode(), LeftChunks[i], RightChunks[i], "", BO), BO));
}
}
break;
}
case Instruction::Call: {
CallInst *CI = cast<CallInst>(I);
Function *F = CI->getCalledFunction();
if (F) {
assert(okToRemainIllegal(F));
return false;
}
Value *CV = CI->getCalledValue();
FunctionType *OFT = NULL;
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
assert(CE);
assert(CE->getOpcode() == Instruction::BitCast);
OFT = cast<FunctionType>(cast<PointerType>(CE->getType())->getElementType());
Constant *C = CE->getOperand(0);
CV = ConstantExpr::getBitCast(C, getLegalizedFunctionType(OFT)->getPointerTo());
} else {
// this is a function pointer call
OFT = cast<FunctionType>(cast<PointerType>(CV->getType())->getElementType());
// we need to add a bitcast
CV = new BitCastInst(CV, getLegalizedFunctionType(OFT)->getPointerTo(), "", I);
}
// create a call with space for legal args
SmallVector<Value *, 0> Args; // XXX
int Num = OFT->getNumParams();
for (int i = 0; i < Num; i++) {
Type *T = OFT->getParamType(i);
if (!isIllegal(T)) {
Args.push_back(CI->getArgOperand(i));
} else {
assert(T == i64);
ChunksVec ArgChunks = getChunks(CI->getArgOperand(i));
Args.push_back(ArgChunks[0]);
Args.push_back(ArgChunks[1]);
}
}
Instruction *L = CopyDebug(CallInst::Create(CV, Args, "", I), I);
Instruction *H = NULL;
// legalize return value as well, if necessary
if (isIllegal(I->getType())) {
assert(I->getType() == i64);
ensureFuncs();
H = CopyDebug(CallInst::Create(GetHigh, "", I), I);
Chunks.push_back(L);
Chunks.push_back(H);
} else {
I->replaceAllUsesWith(L);
}
break;
}
case Instruction::FPToUI:
case Instruction::FPToSI: {
assert(I->getType() == i64);
ensureFuncs();
SmallVector<Value *, 1> Args;
Value *Input = I->getOperand(0);
Args.push_back(Input);
Instruction *L, *H;
if (Input->getType()->isFloatTy()) {
L = CopyDebug(CallInst::Create(FtoILow, Args, "", I), I);
H = CopyDebug(CallInst::Create(FtoIHigh, Args, "", I), I);
} else {
L = CopyDebug(CallInst::Create(DtoILow, Args, "", I), I);
H = CopyDebug(CallInst::Create(DtoIHigh, Args, "", I), I);
}
Chunks.push_back(L);
Chunks.push_back(H);
break;
}
case Instruction::BitCast: {
if (I->getType() == Type::getDoubleTy(TheModule->getContext())) {
// fall through to itofp
} else if (I->getOperand(0)->getType() == Type::getDoubleTy(TheModule->getContext())) {
// double to i64
assert(I->getType() == i64);
ensureFuncs();
SmallVector<Value *, 1> Args;
Args.push_back(I->getOperand(0));
Instruction *L = CopyDebug(CallInst::Create(BDtoILow, Args, "", I), I);
Instruction *H = CopyDebug(CallInst::Create(BDtoIHigh, Args, "", I), I);
Chunks.push_back(L);
Chunks.push_back(H);
break;
} else {
// no-op bitcast
assert(I->getType() == I->getOperand(0)->getType());
Chunks = getChunks(I->getOperand(0));
break;
}
}
case Instruction::SIToFP:
case Instruction::UIToFP: {
assert(I->getOperand(0)->getType() == i64);
ensureFuncs();
ChunksVec InputChunks = getChunks(I->getOperand(0));
Function *F;
switch (I->getOpcode()) {
case Instruction::SIToFP: F = I->getType() == Type::getDoubleTy(TheModule->getContext()) ? SItoD : SItoF; break;
case Instruction::UIToFP: F = I->getType() == Type::getDoubleTy(TheModule->getContext()) ? UItoD : UItoF; break;
case Instruction::BitCast: {
assert(I->getType() == Type::getDoubleTy(TheModule->getContext()));
F = BItoD;
break;
}
default: assert(0);
}
Instruction *D = CopyDebug(CallInst::Create(F, InputChunks, "", I), I);
I->replaceAllUsesWith(D);
break;
}
case Instruction::Switch: {
assert(I->getOperand(0)->getType() == i64);
ChunksVec InputChunks = getChunks(I->getOperand(0));
// do a switch on the lower 32 bits, into a different basic block for each target, then do a branch in each of those on the high 32 bits
SwitchInst* SI = cast<SwitchInst>(I);
BasicBlock *DD = SI->getDefaultDest();
BasicBlock *SwitchBB = I->getParent();
Function *F = SwitchBB->getParent();
unsigned NumItems = 0;
for (SwitchInst::CaseIt i = SI->case_begin(), e = SI->case_end(); i != e; ++i) {
NumItems += i.getCaseValueEx().getNumItems();
}
SwitchInst *LowSI = SwitchInst::Create(InputChunks[0], DD, NumItems, I); // same default destination: if lower bits do not match, go straight to default
CopyDebug(LowSI, I);
typedef std::pair<uint32_t, BasicBlock*> Pair;
typedef std::vector<Pair> Vec; // vector of pairs of high 32 bits, basic block
typedef std::map<uint32_t, Vec> Map; // maps low 32 bits to their Vec info
Map Groups; // (as two 64-bit values in the switch may share their lower bits)
for (SwitchInst::CaseIt i = SI->case_begin(), e = SI->case_end(); i != e; ++i) {
BasicBlock *BB = i.getCaseSuccessor();
const IntegersSubset CaseVal = i.getCaseValueEx();
assert(CaseVal.isSingleNumbersOnly());
for (unsigned Index = 0; Index < CaseVal.getNumItems(); Index++) {
uint64_t Bits = CaseVal.getSingleNumber(Index).toConstantInt()->getZExtValue();
uint32_t LowBits = (uint32_t)Bits;
uint32_t HighBits = (uint32_t)(Bits >> 32);
Vec& V = Groups[LowBits];
V.push_back(Pair(HighBits, BB));
}
}
unsigned Counter = 0;
BasicBlock *InsertPoint = SwitchBB;
for (Map::iterator GI = Groups.begin(); GI != Groups.end(); GI++) {
uint32_t LowBits = GI->first;
Vec &V = GI->second;
BasicBlock *NewBB = BasicBlock::Create(F->getContext(), "switch64_" + utostr(Counter++), F);
NewBB->moveAfter(InsertPoint);
InsertPoint = NewBB;
LowSI->addCase(cast<ConstantInt>(ConstantInt::get(i32, LowBits)), NewBB);
/*if (V.size() == 1) {
// just one option, create a branch
Instruction *CheckHigh = CopyDebug(new ICmpInst(*NewBB, ICmpInst::ICMP_EQ, InputChunks[1], ConstantInt::get(i32, V[0]->first)), I);
Split.ToFix.push_back(CheckHigh);
CopyDebug(BranchInst::Create(V[0]->second, DD, CheckHigh, NewBB), I);
} else {*/
// multiple options, create a switch - we could also optimize and make an icmp/branch if just one, as in commented code above
SwitchInst *HighSI = SwitchInst::Create(InputChunks[1], DD, V.size(), NewBB); // same default destination: if lower bits do not match, go straight to default
for (unsigned i = 0; i < V.size(); i++) {
BasicBlock *BB = V[i].second;
HighSI->addCase(cast<ConstantInt>(ConstantInt::get(i32, V[i].first)), BB);
// fix phis, we used to go SwitchBB->BB, but now go SwitchBB->NewBB->BB, so we look like we arrived from NewBB. Replace the phi from the
// now unneeded SwitchBB to the new BB
for (BasicBlock::iterator I = BB->begin(); I != BB->end(); ++I) {
PHINode *Phi = dyn_cast<PHINode>(I);
if (!Phi) break;
Phi->setIncomingBlock(Phi->getBasicBlockIndex(SwitchBB), NewBB);
}
}
// We used to go SwitchBB->DD, but now go SwitchBB->NewBB->DD, fix that like with BB above. However here we do not replace,
// as the switch BB is still possible to arrive from - we can arrive at the default if either the lower bits were wrong (we
// arrive from the switchBB) or from the NewBB if the high bits were wrong.
for (BasicBlock::iterator I = DD->begin(); I != DD->end(); ++I) {
PHINode *Phi = dyn_cast<PHINode>(I);
if (!Phi) break;
Phi->addIncoming(Phi->getIncomingValue(Phi->getBasicBlockIndex(SwitchBB)), NewBB);
// XXX note that we add a new i64 thing here. now the phi was already an i64 operation, and is being legalized anyhow, but we only notice the original inputs!
// we seem to be safe for now due to order of operation (phis show up after switches, but FIXME
}
}
break;
}
default: {
I->dump();
assert(0 && "some i64 thing we can't legalize yet");
}
}
return true;
}
ChunksVec ExpandI64::getChunks(Value *V) {
assert(isIllegal(V->getType()));
Type *i32 = Type::getInt32Ty(V->getContext());
Value *Zero = ConstantInt::get(i32, 0);
unsigned Num = getNumChunks(V->getType());
if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
APInt C = CI->getValue();
ChunksVec Chunks;
for (unsigned i = 0; i < Num; i++) {
Chunks.push_back(ConstantInt::get(i32, C.trunc(32)));
C = C.lshr(32);
}
return Chunks;
} else if (Instruction *I = dyn_cast<Instruction>(V)) {
assert(Splits.find(I) != Splits.end());
return Splits[I];
} else if (isa<UndefValue>(V)) {
ChunksVec Chunks;
for (unsigned i = 0; i < Num; i++) {
Chunks.push_back(Zero);
}
return Chunks;
} else {
assert(Splits.find(V) != Splits.end());
return Splits[V];
}
}
void ExpandI64::ensureFuncs() {
if (Add != NULL) return;
Type *i32 = Type::getInt32Ty(TheModule->getContext());
SmallVector<Type*, 4> FourArgTypes;
FourArgTypes.push_back(i32);
FourArgTypes.push_back(i32);
FourArgTypes.push_back(i32);
FourArgTypes.push_back(i32);
FunctionType *FourFunc = FunctionType::get(i32, FourArgTypes, false);
Add = Function::Create(FourFunc, GlobalValue::ExternalLinkage,
"i64Add", TheModule);
Sub = Function::Create(FourFunc, GlobalValue::ExternalLinkage,
"i64Subtract", TheModule);
Mul = Function::Create(FourFunc, GlobalValue::ExternalLinkage,
"__muldi3", TheModule);
SDiv = Function::Create(FourFunc, GlobalValue::ExternalLinkage,
"__divdi3", TheModule);
UDiv = Function::Create(FourFunc, GlobalValue::ExternalLinkage,
"__udivdi3", TheModule);
SRem = Function::Create(FourFunc, GlobalValue::ExternalLinkage,
"__remdi3", TheModule);
URem = Function::Create(FourFunc, GlobalValue::ExternalLinkage,
"__uremdi3", TheModule);
LShr = Function::Create(FourFunc, GlobalValue::ExternalLinkage,
"bitshift64Lshr", TheModule);
AShr = Function::Create(FourFunc, GlobalValue::ExternalLinkage,
"bitshift64Ashr", TheModule);
Shl = Function::Create(FourFunc, GlobalValue::ExternalLinkage,
"bitshift64Shl", TheModule);
if (!(GetHigh = TheModule->getFunction("getHigh32"))) {
SmallVector<Type*, 0> GetHighArgTypes;
FunctionType *GetHighFunc = FunctionType::get(i32, GetHighArgTypes, false);
GetHigh = Function::Create(GetHighFunc, GlobalValue::ExternalLinkage,
"getHigh32", TheModule);
}
Type *V = Type::getVoidTy(TheModule->getContext());
SmallVector<Type*, 1> SetHighArgTypes;
SetHighArgTypes.push_back(i32);
FunctionType *SetHighFunc = FunctionType::get(V, SetHighArgTypes, false);
SetHigh = Function::Create(SetHighFunc, GlobalValue::ExternalLinkage,
"setHigh32", TheModule);
Type *Double = Type::getDoubleTy(TheModule->getContext());
Type *Float = Type::getFloatTy(TheModule->getContext());
SmallVector<Type*, 1> FtoITypes;
FtoITypes.push_back(Float);
FunctionType *FtoIFunc = FunctionType::get(i32, FtoITypes, false);
SmallVector<Type*, 1> DtoITypes;
DtoITypes.push_back(Double);
FunctionType *DtoIFunc = FunctionType::get(i32, DtoITypes, false);
FtoILow = Function::Create(FtoIFunc, GlobalValue::ExternalLinkage,
"FtoILow", TheModule);
FtoIHigh = Function::Create(FtoIFunc, GlobalValue::ExternalLinkage,
"FtoIHigh", TheModule);
DtoILow = Function::Create(DtoIFunc, GlobalValue::ExternalLinkage,
"DtoILow", TheModule);
DtoIHigh = Function::Create(DtoIFunc, GlobalValue::ExternalLinkage,
"DtoIHigh", TheModule);
BDtoILow = Function::Create(DtoIFunc, GlobalValue::ExternalLinkage,
"BDtoILow", TheModule);
BDtoIHigh = Function::Create(DtoIFunc, GlobalValue::ExternalLinkage,
"BDtoIHigh", TheModule);
SmallVector<Type*, 2> ItoTypes;
ItoTypes.push_back(i32);
ItoTypes.push_back(i32);
FunctionType *ItoFFunc = FunctionType::get(Float, ItoTypes, false);
SItoF = Function::Create(ItoFFunc, GlobalValue::ExternalLinkage,
"SItoF", TheModule);
UItoF = Function::Create(ItoFFunc, GlobalValue::ExternalLinkage,
"UItoF", TheModule);
FunctionType *ItoDFunc = FunctionType::get(Double, ItoTypes, false);
SItoD = Function::Create(ItoDFunc, GlobalValue::ExternalLinkage,
"SItoD", TheModule);
UItoD = Function::Create(ItoDFunc, GlobalValue::ExternalLinkage,
"UItoD", TheModule);
BItoD = Function::Create(ItoDFunc, GlobalValue::ExternalLinkage,
"BItoD", TheModule);
}
bool ExpandI64::runOnModule(Module &M) {
TheModule = &M;
DL = &getAnalysis<DataLayout>();
Splits.clear();
Changed = false;
// pre pass - legalize functions
for (Module::iterator Iter = M.begin(), E = M.end(); Iter != E; ) {
Function *Func = Iter++;
ensureLegalFunc(Func);
}
// first pass - split
DeadVec Dead;
for (Module::iterator Iter = M.begin(), E = M.end(); Iter != E; ++Iter) {
Function *Func = Iter;
if (Func->isDeclaration()) {
continue;
}
// Walk the body of the function. We use reverse postorder so that we visit
// all operands of an instruction before the instruction itself. The
// exception to this is PHI nodes, which we put on a list and handle below.
ReversePostOrderTraversal<Function*> RPOT(Func);
for (ReversePostOrderTraversal<Function*>::rpo_iterator RI = RPOT.begin(),
RE = RPOT.end(); RI != RE; ++RI) {
BasicBlock *BB = *RI;
for (BasicBlock::iterator Iter = BB->begin(), E = BB->end();
Iter != E; ) {
Instruction *I = Iter++;
if (!isLegalInstruction(I)) {
if (splitInst(I)) {
Changed = true;
Dead.push_back(I);
}
}
}
}
// Fix up PHI node operands.
while (!Phis.empty()) {
PHINode *PN = Phis.pop_back_val();
ChunksVec OutputChunks = getChunks(PN);
for (unsigned j = 0, je = PN->getNumIncomingValues(); j != je; ++j) {
Value *Op = PN->getIncomingValue(j);
ChunksVec InputChunks = getChunks(Op);
for (unsigned k = 0, ke = OutputChunks.size(); k != ke; ++k) {
PHINode *NewPN = cast<PHINode>(OutputChunks[k]);
NewPN->addIncoming(InputChunks[k], PN->getIncomingBlock(j));
}
}
PN->dropAllReferences();
}
// Delete instructions which were replaced. We do this after the full walk
// of the instructions so that all uses are replaced first.
while (!Dead.empty()) {
Instruction *D = Dead.pop_back_val();
D->eraseFromParent();
}
// We only visited blocks found by a DFS walk from the entry, so we haven't
// visited any unreachable blocks, and they may still contain illegal
// instructions at this point. Being unreachable, they can simply be deleted.
removeUnreachableBlocks(*Func);
}
// post pass - clean up illegal functions that were legalized. We do this
// after the full walk of the functions so that all uses are replaced first.
for (Module::iterator Iter = M.begin(), E = M.end(); Iter != E; ) {
Function *Func = Iter++;
removeIllegalFunc(Func);
}
return Changed;
}
void ExpandI64::getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<DataLayout>();
ModulePass::getAnalysisUsage(AU);
}
ModulePass *llvm::createExpandI64Pass() {
return new ExpandI64();
}
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