llvm-project/llvm/lib/Target/AMDGPU/AMDGPUPrintfRuntimeBinding.cpp
Reid Kleckner 05da2fe521 Sink all InitializePasses.h includes
This file lists every pass in LLVM, and is included by Pass.h, which is
very popular. Every time we add, remove, or rename a pass in LLVM, it
caused lots of recompilation.

I found this fact by looking at this table, which is sorted by the
number of times a file was changed over the last 100,000 git commits
multiplied by the number of object files that depend on it in the
current checkout:
  recompiles    touches affected_files  header
  342380        95      3604    llvm/include/llvm/ADT/STLExtras.h
  314730        234     1345    llvm/include/llvm/InitializePasses.h
  307036        118     2602    llvm/include/llvm/ADT/APInt.h
  213049        59      3611    llvm/include/llvm/Support/MathExtras.h
  170422        47      3626    llvm/include/llvm/Support/Compiler.h
  162225        45      3605    llvm/include/llvm/ADT/Optional.h
  158319        63      2513    llvm/include/llvm/ADT/Triple.h
  140322        39      3598    llvm/include/llvm/ADT/StringRef.h
  137647        59      2333    llvm/include/llvm/Support/Error.h
  131619        73      1803    llvm/include/llvm/Support/FileSystem.h

Before this change, touching InitializePasses.h would cause 1345 files
to recompile. After this change, touching it only causes 550 compiles in
an incremental rebuild.

Reviewers: bkramer, asbirlea, bollu, jdoerfert

Differential Revision: https://reviews.llvm.org/D70211
2019-11-13 16:34:37 -08:00

594 lines
22 KiB
C++

//=== AMDGPUPrintfRuntimeBinding.cpp - OpenCL printf 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
//
// The pass bind printfs to a kernel arg pointer that will be bound to a buffer
// later by the runtime.
//
// This pass traverses the functions in the module and converts
// each call to printf to a sequence of operations that
// store the following into the printf buffer:
// - format string (passed as a module's metadata unique ID)
// - bitwise copies of printf arguments
// The backend passes will need to store metadata in the kernel
//===----------------------------------------------------------------------===//
#include "AMDGPU.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/InitializePasses.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
using namespace llvm;
#define DEBUG_TYPE "printfToRuntime"
#define DWORD_ALIGN 4
namespace {
class LLVM_LIBRARY_VISIBILITY AMDGPUPrintfRuntimeBinding final
: public ModulePass {
public:
static char ID;
explicit AMDGPUPrintfRuntimeBinding();
private:
bool runOnModule(Module &M) override;
void getConversionSpecifiers(SmallVectorImpl<char> &OpConvSpecifiers,
StringRef fmt, size_t num_ops) const;
bool shouldPrintAsStr(char Specifier, Type *OpType) const;
bool
lowerPrintfForGpu(Module &M,
function_ref<const TargetLibraryInfo &(Function &)> GetTLI);
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<TargetLibraryInfoWrapperPass>();
AU.addRequired<DominatorTreeWrapperPass>();
}
Value *simplify(Instruction *I, const TargetLibraryInfo *TLI) {
return SimplifyInstruction(I, {*TD, TLI, DT});
}
const DataLayout *TD;
const DominatorTree *DT;
SmallVector<CallInst *, 32> Printfs;
};
} // namespace
char AMDGPUPrintfRuntimeBinding::ID = 0;
INITIALIZE_PASS_BEGIN(AMDGPUPrintfRuntimeBinding,
"amdgpu-printf-runtime-binding", "AMDGPU Printf lowering",
false, false)
INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_END(AMDGPUPrintfRuntimeBinding, "amdgpu-printf-runtime-binding",
"AMDGPU Printf lowering", false, false)
char &llvm::AMDGPUPrintfRuntimeBindingID = AMDGPUPrintfRuntimeBinding::ID;
namespace llvm {
ModulePass *createAMDGPUPrintfRuntimeBinding() {
return new AMDGPUPrintfRuntimeBinding();
}
} // namespace llvm
AMDGPUPrintfRuntimeBinding::AMDGPUPrintfRuntimeBinding()
: ModulePass(ID), TD(nullptr), DT(nullptr) {
initializeAMDGPUPrintfRuntimeBindingPass(*PassRegistry::getPassRegistry());
}
void AMDGPUPrintfRuntimeBinding::getConversionSpecifiers(
SmallVectorImpl<char> &OpConvSpecifiers, StringRef Fmt,
size_t NumOps) const {
// not all format characters are collected.
// At this time the format characters of interest
// are %p and %s, which use to know if we
// are either storing a literal string or a
// pointer to the printf buffer.
static const char ConvSpecifiers[] = "cdieEfgGaosuxXp";
size_t CurFmtSpecifierIdx = 0;
size_t PrevFmtSpecifierIdx = 0;
while ((CurFmtSpecifierIdx = Fmt.find_first_of(
ConvSpecifiers, CurFmtSpecifierIdx)) != StringRef::npos) {
bool ArgDump = false;
StringRef CurFmt = Fmt.substr(PrevFmtSpecifierIdx,
CurFmtSpecifierIdx - PrevFmtSpecifierIdx);
size_t pTag = CurFmt.find_last_of("%");
if (pTag != StringRef::npos) {
ArgDump = true;
while (pTag && CurFmt[--pTag] == '%') {
ArgDump = !ArgDump;
}
}
if (ArgDump)
OpConvSpecifiers.push_back(Fmt[CurFmtSpecifierIdx]);
PrevFmtSpecifierIdx = ++CurFmtSpecifierIdx;
}
}
bool AMDGPUPrintfRuntimeBinding::shouldPrintAsStr(char Specifier,
Type *OpType) const {
if (Specifier != 's')
return false;
const PointerType *PT = dyn_cast<PointerType>(OpType);
if (!PT || PT->getAddressSpace() != AMDGPUAS::CONSTANT_ADDRESS)
return false;
Type *ElemType = PT->getContainedType(0);
if (ElemType->getTypeID() != Type::IntegerTyID)
return false;
IntegerType *ElemIType = cast<IntegerType>(ElemType);
return ElemIType->getBitWidth() == 8;
}
bool AMDGPUPrintfRuntimeBinding::lowerPrintfForGpu(
Module &M, function_ref<const TargetLibraryInfo &(Function &)> GetTLI) {
LLVMContext &Ctx = M.getContext();
IRBuilder<> Builder(Ctx);
Type *I32Ty = Type::getInt32Ty(Ctx);
unsigned UniqID = 0;
// NB: This is important for this string size to be divizable by 4
const char NonLiteralStr[4] = "???";
for (auto CI : Printfs) {
unsigned NumOps = CI->getNumArgOperands();
SmallString<16> OpConvSpecifiers;
Value *Op = CI->getArgOperand(0);
if (auto LI = dyn_cast<LoadInst>(Op)) {
Op = LI->getPointerOperand();
for (auto Use : Op->users()) {
if (auto SI = dyn_cast<StoreInst>(Use)) {
Op = SI->getValueOperand();
break;
}
}
}
if (auto I = dyn_cast<Instruction>(Op)) {
Value *Op_simplified = simplify(I, &GetTLI(*I->getFunction()));
if (Op_simplified)
Op = Op_simplified;
}
ConstantExpr *ConstExpr = dyn_cast<ConstantExpr>(Op);
if (ConstExpr) {
GlobalVariable *GVar = dyn_cast<GlobalVariable>(ConstExpr->getOperand(0));
StringRef Str("unknown");
if (GVar && GVar->hasInitializer()) {
auto Init = GVar->getInitializer();
if (auto CA = dyn_cast<ConstantDataArray>(Init)) {
if (CA->isString())
Str = CA->getAsCString();
} else if (isa<ConstantAggregateZero>(Init)) {
Str = "";
}
//
// we need this call to ascertain
// that we are printing a string
// or a pointer. It takes out the
// specifiers and fills up the first
// arg
getConversionSpecifiers(OpConvSpecifiers, Str, NumOps - 1);
}
// Add metadata for the string
std::string AStreamHolder;
raw_string_ostream Sizes(AStreamHolder);
int Sum = DWORD_ALIGN;
Sizes << CI->getNumArgOperands() - 1;
Sizes << ':';
for (unsigned ArgCount = 1; ArgCount < CI->getNumArgOperands() &&
ArgCount <= OpConvSpecifiers.size();
ArgCount++) {
Value *Arg = CI->getArgOperand(ArgCount);
Type *ArgType = Arg->getType();
unsigned ArgSize = TD->getTypeAllocSizeInBits(ArgType);
ArgSize = ArgSize / 8;
//
// ArgSize by design should be a multiple of DWORD_ALIGN,
// expand the arguments that do not follow this rule.
//
if (ArgSize % DWORD_ALIGN != 0) {
llvm::Type *ResType = llvm::Type::getInt32Ty(Ctx);
VectorType *LLVMVecType = llvm::dyn_cast<llvm::VectorType>(ArgType);
int NumElem = LLVMVecType ? LLVMVecType->getNumElements() : 1;
if (LLVMVecType && NumElem > 1)
ResType = llvm::VectorType::get(ResType, NumElem);
Builder.SetInsertPoint(CI);
Builder.SetCurrentDebugLocation(CI->getDebugLoc());
if (OpConvSpecifiers[ArgCount - 1] == 'x' ||
OpConvSpecifiers[ArgCount - 1] == 'X' ||
OpConvSpecifiers[ArgCount - 1] == 'u' ||
OpConvSpecifiers[ArgCount - 1] == 'o')
Arg = Builder.CreateZExt(Arg, ResType);
else
Arg = Builder.CreateSExt(Arg, ResType);
ArgType = Arg->getType();
ArgSize = TD->getTypeAllocSizeInBits(ArgType);
ArgSize = ArgSize / 8;
CI->setOperand(ArgCount, Arg);
}
if (OpConvSpecifiers[ArgCount - 1] == 'f') {
ConstantFP *FpCons = dyn_cast<ConstantFP>(Arg);
if (FpCons)
ArgSize = 4;
else {
FPExtInst *FpExt = dyn_cast<FPExtInst>(Arg);
if (FpExt && FpExt->getType()->isDoubleTy() &&
FpExt->getOperand(0)->getType()->isFloatTy())
ArgSize = 4;
}
}
if (shouldPrintAsStr(OpConvSpecifiers[ArgCount - 1], ArgType)) {
if (ConstantExpr *ConstExpr = dyn_cast<ConstantExpr>(Arg)) {
GlobalVariable *GV =
dyn_cast<GlobalVariable>(ConstExpr->getOperand(0));
if (GV && GV->hasInitializer()) {
Constant *Init = GV->getInitializer();
ConstantDataArray *CA = dyn_cast<ConstantDataArray>(Init);
if (Init->isZeroValue() || CA->isString()) {
size_t SizeStr = Init->isZeroValue()
? 1
: (strlen(CA->getAsCString().data()) + 1);
size_t Rem = SizeStr % DWORD_ALIGN;
size_t NSizeStr = 0;
LLVM_DEBUG(dbgs() << "Printf string original size = " << SizeStr
<< '\n');
if (Rem) {
NSizeStr = SizeStr + (DWORD_ALIGN - Rem);
} else {
NSizeStr = SizeStr;
}
ArgSize = NSizeStr;
}
} else {
ArgSize = sizeof(NonLiteralStr);
}
} else {
ArgSize = sizeof(NonLiteralStr);
}
}
LLVM_DEBUG(dbgs() << "Printf ArgSize (in buffer) = " << ArgSize
<< " for type: " << *ArgType << '\n');
Sizes << ArgSize << ':';
Sum += ArgSize;
}
LLVM_DEBUG(dbgs() << "Printf format string in source = " << Str.str()
<< '\n');
for (size_t I = 0; I < Str.size(); ++I) {
// Rest of the C escape sequences (e.g. \') are handled correctly
// by the MDParser
switch (Str[I]) {
case '\a':
Sizes << "\\a";
break;
case '\b':
Sizes << "\\b";
break;
case '\f':
Sizes << "\\f";
break;
case '\n':
Sizes << "\\n";
break;
case '\r':
Sizes << "\\r";
break;
case '\v':
Sizes << "\\v";
break;
case ':':
// ':' cannot be scanned by Flex, as it is defined as a delimiter
// Replace it with it's octal representation \72
Sizes << "\\72";
break;
default:
Sizes << Str[I];
break;
}
}
// Insert the printf_alloc call
Builder.SetInsertPoint(CI);
Builder.SetCurrentDebugLocation(CI->getDebugLoc());
AttributeList Attr = AttributeList::get(Ctx, AttributeList::FunctionIndex,
Attribute::NoUnwind);
Type *SizetTy = Type::getInt32Ty(Ctx);
Type *Tys_alloc[1] = {SizetTy};
Type *I8Ptr = PointerType::get(Type::getInt8Ty(Ctx), 1);
FunctionType *FTy_alloc = FunctionType::get(I8Ptr, Tys_alloc, false);
FunctionCallee PrintfAllocFn =
M.getOrInsertFunction(StringRef("__printf_alloc"), FTy_alloc, Attr);
LLVM_DEBUG(dbgs() << "Printf metadata = " << Sizes.str() << '\n');
std::string fmtstr = itostr(++UniqID) + ":" + Sizes.str().c_str();
MDString *fmtStrArray = MDString::get(Ctx, fmtstr);
// Instead of creating global variables, the
// printf format strings are extracted
// and passed as metadata. This avoids
// polluting llvm's symbol tables in this module.
// Metadata is going to be extracted
// by the backend passes and inserted
// into the OpenCL binary as appropriate.
StringRef amd("llvm.printf.fmts");
NamedMDNode *metaD = M.getOrInsertNamedMetadata(amd);
MDNode *myMD = MDNode::get(Ctx, fmtStrArray);
metaD->addOperand(myMD);
Value *sumC = ConstantInt::get(SizetTy, Sum, false);
SmallVector<Value *, 1> alloc_args;
alloc_args.push_back(sumC);
CallInst *pcall =
CallInst::Create(PrintfAllocFn, alloc_args, "printf_alloc_fn", CI);
//
// Insert code to split basicblock with a
// piece of hammock code.
// basicblock splits after buffer overflow check
//
ConstantPointerNull *zeroIntPtr =
ConstantPointerNull::get(PointerType::get(Type::getInt8Ty(Ctx), 1));
ICmpInst *cmp =
dyn_cast<ICmpInst>(Builder.CreateICmpNE(pcall, zeroIntPtr, ""));
if (!CI->use_empty()) {
Value *result =
Builder.CreateSExt(Builder.CreateNot(cmp), I32Ty, "printf_res");
CI->replaceAllUsesWith(result);
}
SplitBlock(CI->getParent(), cmp);
Instruction *Brnch =
SplitBlockAndInsertIfThen(cmp, cmp->getNextNode(), false);
Builder.SetInsertPoint(Brnch);
// store unique printf id in the buffer
//
SmallVector<Value *, 1> ZeroIdxList;
ConstantInt *zeroInt =
ConstantInt::get(Ctx, APInt(32, StringRef("0"), 10));
ZeroIdxList.push_back(zeroInt);
GetElementPtrInst *BufferIdx =
dyn_cast<GetElementPtrInst>(GetElementPtrInst::Create(
nullptr, pcall, ZeroIdxList, "PrintBuffID", Brnch));
Type *idPointer = PointerType::get(I32Ty, AMDGPUAS::GLOBAL_ADDRESS);
Value *id_gep_cast =
new BitCastInst(BufferIdx, idPointer, "PrintBuffIdCast", Brnch);
StoreInst *stbuff =
new StoreInst(ConstantInt::get(I32Ty, UniqID), id_gep_cast);
stbuff->insertBefore(Brnch); // to Remove unused variable warning
SmallVector<Value *, 2> FourthIdxList;
ConstantInt *fourInt =
ConstantInt::get(Ctx, APInt(32, StringRef("4"), 10));
FourthIdxList.push_back(fourInt); // 1st 4 bytes hold the printf_id
// the following GEP is the buffer pointer
BufferIdx = cast<GetElementPtrInst>(GetElementPtrInst::Create(
nullptr, pcall, FourthIdxList, "PrintBuffGep", Brnch));
Type *Int32Ty = Type::getInt32Ty(Ctx);
Type *Int64Ty = Type::getInt64Ty(Ctx);
for (unsigned ArgCount = 1; ArgCount < CI->getNumArgOperands() &&
ArgCount <= OpConvSpecifiers.size();
ArgCount++) {
Value *Arg = CI->getArgOperand(ArgCount);
Type *ArgType = Arg->getType();
SmallVector<Value *, 32> WhatToStore;
if (ArgType->isFPOrFPVectorTy() &&
(ArgType->getTypeID() != Type::VectorTyID)) {
Type *IType = (ArgType->isFloatTy()) ? Int32Ty : Int64Ty;
if (OpConvSpecifiers[ArgCount - 1] == 'f') {
ConstantFP *fpCons = dyn_cast<ConstantFP>(Arg);
if (fpCons) {
APFloat Val(fpCons->getValueAPF());
bool Lost = false;
Val.convert(APFloat::IEEEsingle(), APFloat::rmNearestTiesToEven,
&Lost);
Arg = ConstantFP::get(Ctx, Val);
IType = Int32Ty;
} else {
FPExtInst *FpExt = dyn_cast<FPExtInst>(Arg);
if (FpExt && FpExt->getType()->isDoubleTy() &&
FpExt->getOperand(0)->getType()->isFloatTy()) {
Arg = FpExt->getOperand(0);
IType = Int32Ty;
}
}
}
Arg = new BitCastInst(Arg, IType, "PrintArgFP", Brnch);
WhatToStore.push_back(Arg);
} else if (ArgType->getTypeID() == Type::PointerTyID) {
if (shouldPrintAsStr(OpConvSpecifiers[ArgCount - 1], ArgType)) {
const char *S = NonLiteralStr;
if (ConstantExpr *ConstExpr = dyn_cast<ConstantExpr>(Arg)) {
GlobalVariable *GV =
dyn_cast<GlobalVariable>(ConstExpr->getOperand(0));
if (GV && GV->hasInitializer()) {
Constant *Init = GV->getInitializer();
ConstantDataArray *CA = dyn_cast<ConstantDataArray>(Init);
if (Init->isZeroValue() || CA->isString()) {
S = Init->isZeroValue() ? "" : CA->getAsCString().data();
}
}
}
size_t SizeStr = strlen(S) + 1;
size_t Rem = SizeStr % DWORD_ALIGN;
size_t NSizeStr = 0;
if (Rem) {
NSizeStr = SizeStr + (DWORD_ALIGN - Rem);
} else {
NSizeStr = SizeStr;
}
if (S[0]) {
char *MyNewStr = new char[NSizeStr]();
strcpy(MyNewStr, S);
int NumInts = NSizeStr / 4;
int CharC = 0;
while (NumInts) {
int ANum = *(int *)(MyNewStr + CharC);
CharC += 4;
NumInts--;
Value *ANumV = ConstantInt::get(Int32Ty, ANum, false);
WhatToStore.push_back(ANumV);
}
delete[] MyNewStr;
} else {
// Empty string, give a hint to RT it is no NULL
Value *ANumV = ConstantInt::get(Int32Ty, 0xFFFFFF00, false);
WhatToStore.push_back(ANumV);
}
} else {
uint64_t Size = TD->getTypeAllocSizeInBits(ArgType);
assert((Size == 32 || Size == 64) && "unsupported size");
Type *DstType = (Size == 32) ? Int32Ty : Int64Ty;
Arg = new PtrToIntInst(Arg, DstType, "PrintArgPtr", Brnch);
WhatToStore.push_back(Arg);
}
} else if (ArgType->getTypeID() == Type::VectorTyID) {
Type *IType = NULL;
uint32_t EleCount = cast<VectorType>(ArgType)->getNumElements();
uint32_t EleSize = ArgType->getScalarSizeInBits();
uint32_t TotalSize = EleCount * EleSize;
if (EleCount == 3) {
IntegerType *Int32Ty = Type::getInt32Ty(ArgType->getContext());
Constant *Indices[4] = {
ConstantInt::get(Int32Ty, 0), ConstantInt::get(Int32Ty, 1),
ConstantInt::get(Int32Ty, 2), ConstantInt::get(Int32Ty, 2)};
Constant *Mask = ConstantVector::get(Indices);
ShuffleVectorInst *Shuffle = new ShuffleVectorInst(Arg, Arg, Mask);
Shuffle->insertBefore(Brnch);
Arg = Shuffle;
ArgType = Arg->getType();
TotalSize += EleSize;
}
switch (EleSize) {
default:
EleCount = TotalSize / 64;
IType = dyn_cast<Type>(Type::getInt64Ty(ArgType->getContext()));
break;
case 8:
if (EleCount >= 8) {
EleCount = TotalSize / 64;
IType = dyn_cast<Type>(Type::getInt64Ty(ArgType->getContext()));
} else if (EleCount >= 3) {
EleCount = 1;
IType = dyn_cast<Type>(Type::getInt32Ty(ArgType->getContext()));
} else {
EleCount = 1;
IType = dyn_cast<Type>(Type::getInt16Ty(ArgType->getContext()));
}
break;
case 16:
if (EleCount >= 3) {
EleCount = TotalSize / 64;
IType = dyn_cast<Type>(Type::getInt64Ty(ArgType->getContext()));
} else {
EleCount = 1;
IType = dyn_cast<Type>(Type::getInt32Ty(ArgType->getContext()));
}
break;
}
if (EleCount > 1) {
IType = dyn_cast<Type>(VectorType::get(IType, EleCount));
}
Arg = new BitCastInst(Arg, IType, "PrintArgVect", Brnch);
WhatToStore.push_back(Arg);
} else {
WhatToStore.push_back(Arg);
}
for (unsigned I = 0, E = WhatToStore.size(); I != E; ++I) {
Value *TheBtCast = WhatToStore[I];
unsigned ArgSize =
TD->getTypeAllocSizeInBits(TheBtCast->getType()) / 8;
SmallVector<Value *, 1> BuffOffset;
BuffOffset.push_back(ConstantInt::get(I32Ty, ArgSize));
Type *ArgPointer = PointerType::get(TheBtCast->getType(), 1);
Value *CastedGEP =
new BitCastInst(BufferIdx, ArgPointer, "PrintBuffPtrCast", Brnch);
StoreInst *StBuff = new StoreInst(TheBtCast, CastedGEP, Brnch);
LLVM_DEBUG(dbgs() << "inserting store to printf buffer:\n"
<< *StBuff << '\n');
(void)StBuff;
if (I + 1 == E && ArgCount + 1 == CI->getNumArgOperands())
break;
BufferIdx = dyn_cast<GetElementPtrInst>(GetElementPtrInst::Create(
nullptr, BufferIdx, BuffOffset, "PrintBuffNextPtr", Brnch));
LLVM_DEBUG(dbgs() << "inserting gep to the printf buffer:\n"
<< *BufferIdx << '\n');
}
}
}
}
// erase the printf calls
for (auto CI : Printfs)
CI->eraseFromParent();
Printfs.clear();
return true;
}
bool AMDGPUPrintfRuntimeBinding::runOnModule(Module &M) {
Triple TT(M.getTargetTriple());
if (TT.getArch() == Triple::r600)
return false;
auto PrintfFunction = M.getFunction("printf");
if (!PrintfFunction)
return false;
for (auto &U : PrintfFunction->uses()) {
if (auto *CI = dyn_cast<CallInst>(U.getUser())) {
if (CI->isCallee(&U))
Printfs.push_back(CI);
}
}
if (Printfs.empty())
return false;
TD = &M.getDataLayout();
auto DTWP = getAnalysisIfAvailable<DominatorTreeWrapperPass>();
DT = DTWP ? &DTWP->getDomTree() : nullptr;
auto GetTLI = [this](Function &F) -> TargetLibraryInfo & {
return this->getAnalysis<TargetLibraryInfoWrapperPass>().getTLI(F);
};
return lowerPrintfForGpu(M, GetTLI);
}