llvm-6502/lib/Analysis/MemoryBuiltins.cpp

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//===------ MemoryBuiltins.cpp - Identify calls to memory builtins --------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This family of functions identifies calls to builtin functions that allocate
// or free memory.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "memory-builtins"
#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetLibraryInfo.h"
#include "llvm/Transforms/Utils/Local.h"
using namespace llvm;
enum AllocType {
MallocLike = 1<<0, // allocates
CallocLike = 1<<1, // allocates + bzero
ReallocLike = 1<<2, // reallocates
StrDupLike = 1<<3,
AllocLike = MallocLike | CallocLike | StrDupLike,
AnyAlloc = MallocLike | CallocLike | ReallocLike | StrDupLike
};
struct AllocFnsTy {
LibFunc::Func Func;
AllocType AllocTy;
unsigned char NumParams;
// First and Second size parameters (or -1 if unused)
signed char FstParam, SndParam;
};
// FIXME: certain users need more information. E.g., SimplifyLibCalls needs to
// know which functions are nounwind, noalias, nocapture parameters, etc.
static const AllocFnsTy AllocationFnData[] = {
{LibFunc::malloc, MallocLike, 1, 0, -1},
{LibFunc::valloc, MallocLike, 1, 0, -1},
{LibFunc::Znwj, MallocLike, 1, 0, -1}, // new(unsigned int)
{LibFunc::ZnwjRKSt9nothrow_t, MallocLike, 2, 0, -1}, // new(unsigned int, nothrow)
{LibFunc::Znwm, MallocLike, 1, 0, -1}, // new(unsigned long)
{LibFunc::ZnwmRKSt9nothrow_t, MallocLike, 2, 0, -1}, // new(unsigned long, nothrow)
{LibFunc::Znaj, MallocLike, 1, 0, -1}, // new[](unsigned int)
{LibFunc::ZnajRKSt9nothrow_t, MallocLike, 2, 0, -1}, // new[](unsigned int, nothrow)
{LibFunc::Znam, MallocLike, 1, 0, -1}, // new[](unsigned long)
{LibFunc::ZnamRKSt9nothrow_t, MallocLike, 2, 0, -1}, // new[](unsigned long, nothrow)
{LibFunc::posix_memalign, MallocLike, 3, 2, -1},
{LibFunc::calloc, CallocLike, 2, 0, 1},
{LibFunc::realloc, ReallocLike, 2, 1, -1},
{LibFunc::reallocf, ReallocLike, 2, 1, -1},
{LibFunc::strdup, StrDupLike, 1, -1, -1},
{LibFunc::strndup, StrDupLike, 2, 1, -1}
};
static Function *getCalledFunction(const Value *V, bool LookThroughBitCast) {
if (LookThroughBitCast)
V = V->stripPointerCasts();
CallSite CS(const_cast<Value*>(V));
if (!CS.getInstruction())
return 0;
if (CS.isNoBuiltin())
return 0;
Function *Callee = CS.getCalledFunction();
if (!Callee || !Callee->isDeclaration())
return 0;
return Callee;
}
/// \brief Returns the allocation data for the given value if it is a call to a
/// known allocation function, and NULL otherwise.
static const AllocFnsTy *getAllocationData(const Value *V, AllocType AllocTy,
const TargetLibraryInfo *TLI,
bool LookThroughBitCast = false) {
// Skip intrinsics
if (isa<IntrinsicInst>(V))
return 0;
Function *Callee = getCalledFunction(V, LookThroughBitCast);
if (!Callee)
return 0;
// Make sure that the function is available.
StringRef FnName = Callee->getName();
LibFunc::Func TLIFn;
if (!TLI || !TLI->getLibFunc(FnName, TLIFn) || !TLI->has(TLIFn))
return 0;
unsigned i = 0;
bool found = false;
for ( ; i < array_lengthof(AllocationFnData); ++i) {
if (AllocationFnData[i].Func == TLIFn) {
found = true;
break;
}
}
if (!found)
return 0;
const AllocFnsTy *FnData = &AllocationFnData[i];
if ((FnData->AllocTy & AllocTy) == 0)
return 0;
// Check function prototype.
int FstParam = FnData->FstParam;
int SndParam = FnData->SndParam;
FunctionType *FTy = Callee->getFunctionType();
if (FTy->getReturnType() == Type::getInt8PtrTy(FTy->getContext()) &&
FTy->getNumParams() == FnData->NumParams &&
(FstParam < 0 ||
(FTy->getParamType(FstParam)->isIntegerTy(32) ||
FTy->getParamType(FstParam)->isIntegerTy(64))) &&
(SndParam < 0 ||
FTy->getParamType(SndParam)->isIntegerTy(32) ||
FTy->getParamType(SndParam)->isIntegerTy(64)))
return FnData;
return 0;
}
static bool hasNoAliasAttr(const Value *V, bool LookThroughBitCast) {
ImmutableCallSite CS(LookThroughBitCast ? V->stripPointerCasts() : V);
return CS && CS.hasFnAttr(Attribute::NoAlias);
}
/// \brief Tests if a value is a call or invoke to a library function that
/// allocates or reallocates memory (either malloc, calloc, realloc, or strdup
/// like).
bool llvm::isAllocationFn(const Value *V, const TargetLibraryInfo *TLI,
bool LookThroughBitCast) {
return getAllocationData(V, AnyAlloc, TLI, LookThroughBitCast);
}
/// \brief Tests if a value is a call or invoke to a function that returns a
/// NoAlias pointer (including malloc/calloc/realloc/strdup-like functions).
bool llvm::isNoAliasFn(const Value *V, const TargetLibraryInfo *TLI,
bool LookThroughBitCast) {
// it's safe to consider realloc as noalias since accessing the original
// pointer is undefined behavior
return isAllocationFn(V, TLI, LookThroughBitCast) ||
hasNoAliasAttr(V, LookThroughBitCast);
}
/// \brief Tests if a value is a call or invoke to a library function that
/// allocates uninitialized memory (such as malloc).
bool llvm::isMallocLikeFn(const Value *V, const TargetLibraryInfo *TLI,
bool LookThroughBitCast) {
return getAllocationData(V, MallocLike, TLI, LookThroughBitCast);
}
/// \brief Tests if a value is a call or invoke to a library function that
/// allocates zero-filled memory (such as calloc).
bool llvm::isCallocLikeFn(const Value *V, const TargetLibraryInfo *TLI,
bool LookThroughBitCast) {
return getAllocationData(V, CallocLike, TLI, LookThroughBitCast);
}
/// \brief Tests if a value is a call or invoke to a library function that
/// allocates memory (either malloc, calloc, or strdup like).
bool llvm::isAllocLikeFn(const Value *V, const TargetLibraryInfo *TLI,
bool LookThroughBitCast) {
return getAllocationData(V, AllocLike, TLI, LookThroughBitCast);
}
/// \brief Tests if a value is a call or invoke to a library function that
/// reallocates memory (such as realloc).
bool llvm::isReallocLikeFn(const Value *V, const TargetLibraryInfo *TLI,
bool LookThroughBitCast) {
return getAllocationData(V, ReallocLike, TLI, LookThroughBitCast);
}
/// extractMallocCall - Returns the corresponding CallInst if the instruction
/// is a malloc call. Since CallInst::CreateMalloc() only creates calls, we
/// ignore InvokeInst here.
const CallInst *llvm::extractMallocCall(const Value *I,
const TargetLibraryInfo *TLI) {
return isMallocLikeFn(I, TLI) ? dyn_cast<CallInst>(I) : 0;
}
static Value *computeArraySize(const CallInst *CI, const DataLayout *TD,
const TargetLibraryInfo *TLI,
bool LookThroughSExt = false) {
if (!CI)
return 0;
Re-commit r86077 now that r86290 fixes the 179.art and 175.vpr ARM regressions. Here is the original commit message: This commit updates malloc optimizations to operate on malloc calls that have constant int size arguments. Update CreateMalloc so that its callers specify the size to allocate: MallocInst-autoupgrade users use non-TargetData-computed allocation sizes. Optimization uses use TargetData to compute the allocation size. Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays. Extend getMallocType() to support malloc calls that have non-bitcast uses. Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses. The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly. Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses. The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use. Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use. Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86311 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-07 00:16:28 +00:00
// The size of the malloc's result type must be known to determine array size.
Type *T = getMallocAllocatedType(CI, TLI);
Re-commit r86077 now that r86290 fixes the 179.art and 175.vpr ARM regressions. Here is the original commit message: This commit updates malloc optimizations to operate on malloc calls that have constant int size arguments. Update CreateMalloc so that its callers specify the size to allocate: MallocInst-autoupgrade users use non-TargetData-computed allocation sizes. Optimization uses use TargetData to compute the allocation size. Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays. Extend getMallocType() to support malloc calls that have non-bitcast uses. Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses. The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly. Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses. The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use. Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use. Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86311 91177308-0d34-0410-b5e6-96231b3b80d8
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if (!T || !T->isSized() || !TD)
return 0;
unsigned ElementSize = TD->getTypeAllocSize(T);
if (StructType *ST = dyn_cast<StructType>(T))
ElementSize = TD->getStructLayout(ST)->getSizeInBytes();
Re-commit r86077 now that r86290 fixes the 179.art and 175.vpr ARM regressions. Here is the original commit message: This commit updates malloc optimizations to operate on malloc calls that have constant int size arguments. Update CreateMalloc so that its callers specify the size to allocate: MallocInst-autoupgrade users use non-TargetData-computed allocation sizes. Optimization uses use TargetData to compute the allocation size. Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays. Extend getMallocType() to support malloc calls that have non-bitcast uses. Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses. The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly. Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses. The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use. Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use. Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86311 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-07 00:16:28 +00:00
// If malloc call's arg can be determined to be a multiple of ElementSize,
// return the multiple. Otherwise, return NULL.
Value *MallocArg = CI->getArgOperand(0);
Value *Multiple = 0;
if (ComputeMultiple(MallocArg, ElementSize, Multiple,
LookThroughSExt))
return Multiple;
return 0;
}
/// isArrayMalloc - Returns the corresponding CallInst if the instruction
/// is a call to malloc whose array size can be determined and the array size
/// is not constant 1. Otherwise, return NULL.
const CallInst *llvm::isArrayMalloc(const Value *I,
const DataLayout *TD,
const TargetLibraryInfo *TLI) {
const CallInst *CI = extractMallocCall(I, TLI);
Value *ArraySize = computeArraySize(CI, TD, TLI);
if (ConstantInt *ConstSize = dyn_cast_or_null<ConstantInt>(ArraySize))
if (ConstSize->isOne())
return CI;
// CI is a non-array malloc or we can't figure out that it is an array malloc.
return 0;
}
/// getMallocType - Returns the PointerType resulting from the malloc call.
Re-commit r86077 now that r86290 fixes the 179.art and 175.vpr ARM regressions. Here is the original commit message: This commit updates malloc optimizations to operate on malloc calls that have constant int size arguments. Update CreateMalloc so that its callers specify the size to allocate: MallocInst-autoupgrade users use non-TargetData-computed allocation sizes. Optimization uses use TargetData to compute the allocation size. Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays. Extend getMallocType() to support malloc calls that have non-bitcast uses. Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses. The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly. Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses. The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use. Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use. Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86311 91177308-0d34-0410-b5e6-96231b3b80d8
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/// The PointerType depends on the number of bitcast uses of the malloc call:
/// 0: PointerType is the calls' return type.
/// 1: PointerType is the bitcast's result type.
/// >1: Unique PointerType cannot be determined, return NULL.
PointerType *llvm::getMallocType(const CallInst *CI,
const TargetLibraryInfo *TLI) {
assert(isMallocLikeFn(CI, TLI) && "getMallocType and not malloc call");
PointerType *MallocType = 0;
Re-commit r86077 now that r86290 fixes the 179.art and 175.vpr ARM regressions. Here is the original commit message: This commit updates malloc optimizations to operate on malloc calls that have constant int size arguments. Update CreateMalloc so that its callers specify the size to allocate: MallocInst-autoupgrade users use non-TargetData-computed allocation sizes. Optimization uses use TargetData to compute the allocation size. Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays. Extend getMallocType() to support malloc calls that have non-bitcast uses. Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses. The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly. Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses. The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use. Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use. Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86311 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-07 00:16:28 +00:00
unsigned NumOfBitCastUses = 0;
// Determine if CallInst has a bitcast use.
for (Value::const_use_iterator UI = CI->use_begin(), E = CI->use_end();
UI != E; )
Re-commit r86077 now that r86290 fixes the 179.art and 175.vpr ARM regressions. Here is the original commit message: This commit updates malloc optimizations to operate on malloc calls that have constant int size arguments. Update CreateMalloc so that its callers specify the size to allocate: MallocInst-autoupgrade users use non-TargetData-computed allocation sizes. Optimization uses use TargetData to compute the allocation size. Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays. Extend getMallocType() to support malloc calls that have non-bitcast uses. Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses. The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly. Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses. The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use. Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use. Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86311 91177308-0d34-0410-b5e6-96231b3b80d8
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if (const BitCastInst *BCI = dyn_cast<BitCastInst>(*UI++)) {
MallocType = cast<PointerType>(BCI->getDestTy());
NumOfBitCastUses++;
}
Re-commit r86077 now that r86290 fixes the 179.art and 175.vpr ARM regressions. Here is the original commit message: This commit updates malloc optimizations to operate on malloc calls that have constant int size arguments. Update CreateMalloc so that its callers specify the size to allocate: MallocInst-autoupgrade users use non-TargetData-computed allocation sizes. Optimization uses use TargetData to compute the allocation size. Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays. Extend getMallocType() to support malloc calls that have non-bitcast uses. Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses. The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly. Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses. The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use. Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use. Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86311 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-07 00:16:28 +00:00
// Malloc call has 1 bitcast use, so type is the bitcast's destination type.
if (NumOfBitCastUses == 1)
return MallocType;
// Malloc call was not bitcast, so type is the malloc function's return type.
Re-commit r86077 now that r86290 fixes the 179.art and 175.vpr ARM regressions. Here is the original commit message: This commit updates malloc optimizations to operate on malloc calls that have constant int size arguments. Update CreateMalloc so that its callers specify the size to allocate: MallocInst-autoupgrade users use non-TargetData-computed allocation sizes. Optimization uses use TargetData to compute the allocation size. Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays. Extend getMallocType() to support malloc calls that have non-bitcast uses. Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses. The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly. Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses. The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use. Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use. Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86311 91177308-0d34-0410-b5e6-96231b3b80d8
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if (NumOfBitCastUses == 0)
return cast<PointerType>(CI->getType());
// Type could not be determined.
return 0;
}
Re-commit r86077 now that r86290 fixes the 179.art and 175.vpr ARM regressions. Here is the original commit message: This commit updates malloc optimizations to operate on malloc calls that have constant int size arguments. Update CreateMalloc so that its callers specify the size to allocate: MallocInst-autoupgrade users use non-TargetData-computed allocation sizes. Optimization uses use TargetData to compute the allocation size. Now that malloc calls can have constant sizes, update isArrayMallocHelper() to use TargetData to determine the size of the malloced type and the size of malloced arrays. Extend getMallocType() to support malloc calls that have non-bitcast uses. Update OptimizeGlobalAddressOfMalloc() to optimize malloc calls that have non-bitcast uses. The bitcast use of a malloc call has to be treated specially here because the uses of the bitcast need to be replaced and the bitcast needs to be erased (just like the malloc call) for OptimizeGlobalAddressOfMalloc() to work correctly. Update PerformHeapAllocSRoA() to optimize malloc calls that have non-bitcast uses. The bitcast use of the malloc is not handled specially here because ReplaceUsesOfMallocWithGlobal replaces through the bitcast use. Update OptimizeOnceStoredGlobal() to not care about the malloc calls' bitcast use. Update all globalopt malloc tests to not rely on autoupgraded-MallocInsts, but instead use explicit malloc calls with correct allocation sizes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86311 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-07 00:16:28 +00:00
/// getMallocAllocatedType - Returns the Type allocated by malloc call.
/// The Type depends on the number of bitcast uses of the malloc call:
/// 0: PointerType is the malloc calls' return type.
/// 1: PointerType is the bitcast's result type.
/// >1: Unique PointerType cannot be determined, return NULL.
Type *llvm::getMallocAllocatedType(const CallInst *CI,
const TargetLibraryInfo *TLI) {
PointerType *PT = getMallocType(CI, TLI);
return PT ? PT->getElementType() : 0;
}
/// getMallocArraySize - Returns the array size of a malloc call. If the
/// argument passed to malloc is a multiple of the size of the malloced type,
/// then return that multiple. For non-array mallocs, the multiple is
/// constant 1. Otherwise, return NULL for mallocs whose array size cannot be
/// determined.
Value *llvm::getMallocArraySize(CallInst *CI, const DataLayout *TD,
const TargetLibraryInfo *TLI,
bool LookThroughSExt) {
assert(isMallocLikeFn(CI, TLI) && "getMallocArraySize and not malloc call");
return computeArraySize(CI, TD, TLI, LookThroughSExt);
}
/// extractCallocCall - Returns the corresponding CallInst if the instruction
/// is a calloc call.
const CallInst *llvm::extractCallocCall(const Value *I,
const TargetLibraryInfo *TLI) {
return isCallocLikeFn(I, TLI) ? cast<CallInst>(I) : 0;
}
/// isFreeCall - Returns non-null if the value is a call to the builtin free()
const CallInst *llvm::isFreeCall(const Value *I, const TargetLibraryInfo *TLI) {
const CallInst *CI = dyn_cast<CallInst>(I);
if (!CI || isa<IntrinsicInst>(CI))
return 0;
Function *Callee = CI->getCalledFunction();
if (Callee == 0 || !Callee->isDeclaration())
return 0;
StringRef FnName = Callee->getName();
LibFunc::Func TLIFn;
if (!TLI || !TLI->getLibFunc(FnName, TLIFn) || !TLI->has(TLIFn))
return 0;
unsigned ExpectedNumParams;
if (TLIFn == LibFunc::free ||
TLIFn == LibFunc::ZdlPv || // operator delete(void*)
TLIFn == LibFunc::ZdaPv) // operator delete[](void*)
ExpectedNumParams = 1;
else if (TLIFn == LibFunc::ZdlPvRKSt9nothrow_t || // delete(void*, nothrow)
TLIFn == LibFunc::ZdaPvRKSt9nothrow_t) // delete[](void*, nothrow)
ExpectedNumParams = 2;
else
return 0;
// Check free prototype.
// FIXME: workaround for PR5130, this will be obsolete when a nobuiltin
// attribute will exist.
FunctionType *FTy = Callee->getFunctionType();
if (!FTy->getReturnType()->isVoidTy())
return 0;
if (FTy->getNumParams() != ExpectedNumParams)
return 0;
if (FTy->getParamType(0) != Type::getInt8PtrTy(Callee->getContext()))
return 0;
return CI;
}
//===----------------------------------------------------------------------===//
// Utility functions to compute size of objects.
//
/// \brief Compute the size of the object pointed by Ptr. Returns true and the
/// object size in Size if successful, and false otherwise.
/// If RoundToAlign is true, then Size is rounded up to the aligment of allocas,
/// byval arguments, and global variables.
bool llvm::getObjectSize(const Value *Ptr, uint64_t &Size, const DataLayout *TD,
const TargetLibraryInfo *TLI, bool RoundToAlign) {
if (!TD)
return false;
ObjectSizeOffsetVisitor Visitor(TD, TLI, Ptr->getContext(), RoundToAlign);
SizeOffsetType Data = Visitor.compute(const_cast<Value*>(Ptr));
if (!Visitor.bothKnown(Data))
return false;
APInt ObjSize = Data.first, Offset = Data.second;
// check for overflow
if (Offset.slt(0) || ObjSize.ult(Offset))
Size = 0;
else
Size = (ObjSize - Offset).getZExtValue();
return true;
}
STATISTIC(ObjectVisitorArgument,
"Number of arguments with unsolved size and offset");
STATISTIC(ObjectVisitorLoad,
"Number of load instructions with unsolved size and offset");
APInt ObjectSizeOffsetVisitor::align(APInt Size, uint64_t Align) {
if (RoundToAlign && Align)
return APInt(IntTyBits, RoundUpToAlignment(Size.getZExtValue(), Align));
return Size;
}
ObjectSizeOffsetVisitor::ObjectSizeOffsetVisitor(const DataLayout *TD,
const TargetLibraryInfo *TLI,
LLVMContext &Context,
Revert the series of commits starting with r166578 which introduced the getIntPtrType support for multiple address spaces via a pointer type, and also introduced a crasher bug in the constant folder reported in PR14233. These commits also contained several problems that should really be addressed before they are re-committed. I have avoided reverting various cleanups to the DataLayout APIs that are reasonable to have moving forward in order to reduce the amount of churn, and minimize the number of commits that were reverted. I've also manually updated merge conflicts and manually arranged for the getIntPtrType function to stay in DataLayout and to be defined in a plausible way after this revert. Thanks to Duncan for working through this exact strategy with me, and Nick Lewycky for tracking down the really annoying crasher this triggered. (Test case to follow in its own commit.) After discussing with Duncan extensively, and based on a note from Micah, I'm going to continue to back out some more of the more problematic patches in this series in order to ensure we go into the LLVM 3.2 branch with a reasonable story here. I'll send a note to llvmdev explaining what's going on and why. Summary of reverted revisions: r166634: Fix a compiler warning with an unused variable. r166607: Add some cleanup to the DataLayout changes requested by Chandler. r166596: Revert "Back out r166591, not sure why this made it through since I cancelled the command. Bleh, sorry about this! r166591: Delete a directory that wasn't supposed to be checked in yet. r166578: Add in support for getIntPtrType to get the pointer type based on the address space. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167221 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-01 08:07:29 +00:00
bool RoundToAlign)
: TD(TD), TLI(TLI), RoundToAlign(RoundToAlign) {
Revert the series of commits starting with r166578 which introduced the getIntPtrType support for multiple address spaces via a pointer type, and also introduced a crasher bug in the constant folder reported in PR14233. These commits also contained several problems that should really be addressed before they are re-committed. I have avoided reverting various cleanups to the DataLayout APIs that are reasonable to have moving forward in order to reduce the amount of churn, and minimize the number of commits that were reverted. I've also manually updated merge conflicts and manually arranged for the getIntPtrType function to stay in DataLayout and to be defined in a plausible way after this revert. Thanks to Duncan for working through this exact strategy with me, and Nick Lewycky for tracking down the really annoying crasher this triggered. (Test case to follow in its own commit.) After discussing with Duncan extensively, and based on a note from Micah, I'm going to continue to back out some more of the more problematic patches in this series in order to ensure we go into the LLVM 3.2 branch with a reasonable story here. I'll send a note to llvmdev explaining what's going on and why. Summary of reverted revisions: r166634: Fix a compiler warning with an unused variable. r166607: Add some cleanup to the DataLayout changes requested by Chandler. r166596: Revert "Back out r166591, not sure why this made it through since I cancelled the command. Bleh, sorry about this! r166591: Delete a directory that wasn't supposed to be checked in yet. r166578: Add in support for getIntPtrType to get the pointer type based on the address space. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167221 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-01 08:07:29 +00:00
IntegerType *IntTy = TD->getIntPtrType(Context);
IntTyBits = IntTy->getBitWidth();
Zero = APInt::getNullValue(IntTyBits);
}
SizeOffsetType ObjectSizeOffsetVisitor::compute(Value *V) {
V = V->stripPointerCasts();
if (Instruction *I = dyn_cast<Instruction>(V)) {
// If we have already seen this instruction, bail out. Cycles can happen in
// unreachable code after constant propagation.
if (!SeenInsts.insert(I))
return unknown();
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V))
return visitGEPOperator(*GEP);
return visit(*I);
}
if (Argument *A = dyn_cast<Argument>(V))
return visitArgument(*A);
if (ConstantPointerNull *P = dyn_cast<ConstantPointerNull>(V))
return visitConstantPointerNull(*P);
if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V))
return visitGlobalAlias(*GA);
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V))
return visitGlobalVariable(*GV);
if (UndefValue *UV = dyn_cast<UndefValue>(V))
return visitUndefValue(*UV);
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
if (CE->getOpcode() == Instruction::IntToPtr)
return unknown(); // clueless
if (CE->getOpcode() == Instruction::GetElementPtr)
return visitGEPOperator(cast<GEPOperator>(*CE));
}
DEBUG(dbgs() << "ObjectSizeOffsetVisitor::compute() unhandled value: " << *V
<< '\n');
return unknown();
}
SizeOffsetType ObjectSizeOffsetVisitor::visitAllocaInst(AllocaInst &I) {
if (!I.getAllocatedType()->isSized())
return unknown();
APInt Size(IntTyBits, TD->getTypeAllocSize(I.getAllocatedType()));
if (!I.isArrayAllocation())
return std::make_pair(align(Size, I.getAlignment()), Zero);
Value *ArraySize = I.getArraySize();
if (const ConstantInt *C = dyn_cast<ConstantInt>(ArraySize)) {
Size *= C->getValue().zextOrSelf(IntTyBits);
return std::make_pair(align(Size, I.getAlignment()), Zero);
}
return unknown();
}
SizeOffsetType ObjectSizeOffsetVisitor::visitArgument(Argument &A) {
// no interprocedural analysis is done at the moment
if (!A.hasByValAttr()) {
++ObjectVisitorArgument;
return unknown();
}
PointerType *PT = cast<PointerType>(A.getType());
APInt Size(IntTyBits, TD->getTypeAllocSize(PT->getElementType()));
return std::make_pair(align(Size, A.getParamAlignment()), Zero);
}
SizeOffsetType ObjectSizeOffsetVisitor::visitCallSite(CallSite CS) {
const AllocFnsTy *FnData = getAllocationData(CS.getInstruction(), AnyAlloc,
TLI);
if (!FnData)
return unknown();
// handle strdup-like functions separately
if (FnData->AllocTy == StrDupLike) {
APInt Size(IntTyBits, GetStringLength(CS.getArgument(0)));
if (!Size)
return unknown();
// strndup limits strlen
if (FnData->FstParam > 0) {
ConstantInt *Arg= dyn_cast<ConstantInt>(CS.getArgument(FnData->FstParam));
if (!Arg)
return unknown();
APInt MaxSize = Arg->getValue().zextOrSelf(IntTyBits);
if (Size.ugt(MaxSize))
Size = MaxSize + 1;
}
return std::make_pair(Size, Zero);
}
ConstantInt *Arg = dyn_cast<ConstantInt>(CS.getArgument(FnData->FstParam));
if (!Arg)
return unknown();
APInt Size = Arg->getValue().zextOrSelf(IntTyBits);
// size determined by just 1 parameter
if (FnData->SndParam < 0)
return std::make_pair(Size, Zero);
Arg = dyn_cast<ConstantInt>(CS.getArgument(FnData->SndParam));
if (!Arg)
return unknown();
Size *= Arg->getValue().zextOrSelf(IntTyBits);
return std::make_pair(Size, Zero);
// TODO: handle more standard functions (+ wchar cousins):
// - strdup / strndup
// - strcpy / strncpy
// - strcat / strncat
// - memcpy / memmove
// - strcat / strncat
// - memset
}
SizeOffsetType
ObjectSizeOffsetVisitor::visitConstantPointerNull(ConstantPointerNull&) {
return std::make_pair(Zero, Zero);
}
SizeOffsetType
ObjectSizeOffsetVisitor::visitExtractElementInst(ExtractElementInst&) {
return unknown();
}
SizeOffsetType
ObjectSizeOffsetVisitor::visitExtractValueInst(ExtractValueInst&) {
// Easy cases were already folded by previous passes.
return unknown();
}
SizeOffsetType ObjectSizeOffsetVisitor::visitGEPOperator(GEPOperator &GEP) {
SizeOffsetType PtrData = compute(GEP.getPointerOperand());
APInt Offset(IntTyBits, 0);
if (!bothKnown(PtrData) || !GEP.accumulateConstantOffset(*TD, Offset))
return unknown();
return std::make_pair(PtrData.first, PtrData.second + Offset);
}
SizeOffsetType ObjectSizeOffsetVisitor::visitGlobalAlias(GlobalAlias &GA) {
if (GA.mayBeOverridden())
return unknown();
return compute(GA.getAliasee());
}
SizeOffsetType ObjectSizeOffsetVisitor::visitGlobalVariable(GlobalVariable &GV){
if (!GV.hasDefinitiveInitializer())
return unknown();
APInt Size(IntTyBits, TD->getTypeAllocSize(GV.getType()->getElementType()));
return std::make_pair(align(Size, GV.getAlignment()), Zero);
}
SizeOffsetType ObjectSizeOffsetVisitor::visitIntToPtrInst(IntToPtrInst&) {
// clueless
return unknown();
}
SizeOffsetType ObjectSizeOffsetVisitor::visitLoadInst(LoadInst&) {
++ObjectVisitorLoad;
return unknown();
}
SizeOffsetType ObjectSizeOffsetVisitor::visitPHINode(PHINode&) {
// too complex to analyze statically.
return unknown();
}
SizeOffsetType ObjectSizeOffsetVisitor::visitSelectInst(SelectInst &I) {
SizeOffsetType TrueSide = compute(I.getTrueValue());
SizeOffsetType FalseSide = compute(I.getFalseValue());
if (bothKnown(TrueSide) && bothKnown(FalseSide) && TrueSide == FalseSide)
return TrueSide;
return unknown();
}
SizeOffsetType ObjectSizeOffsetVisitor::visitUndefValue(UndefValue&) {
return std::make_pair(Zero, Zero);
}
SizeOffsetType ObjectSizeOffsetVisitor::visitInstruction(Instruction &I) {
DEBUG(dbgs() << "ObjectSizeOffsetVisitor unknown instruction:" << I << '\n');
return unknown();
}
ObjectSizeOffsetEvaluator::ObjectSizeOffsetEvaluator(const DataLayout *TD,
const TargetLibraryInfo *TLI,
Revert the series of commits starting with r166578 which introduced the getIntPtrType support for multiple address spaces via a pointer type, and also introduced a crasher bug in the constant folder reported in PR14233. These commits also contained several problems that should really be addressed before they are re-committed. I have avoided reverting various cleanups to the DataLayout APIs that are reasonable to have moving forward in order to reduce the amount of churn, and minimize the number of commits that were reverted. I've also manually updated merge conflicts and manually arranged for the getIntPtrType function to stay in DataLayout and to be defined in a plausible way after this revert. Thanks to Duncan for working through this exact strategy with me, and Nick Lewycky for tracking down the really annoying crasher this triggered. (Test case to follow in its own commit.) After discussing with Duncan extensively, and based on a note from Micah, I'm going to continue to back out some more of the more problematic patches in this series in order to ensure we go into the LLVM 3.2 branch with a reasonable story here. I'll send a note to llvmdev explaining what's going on and why. Summary of reverted revisions: r166634: Fix a compiler warning with an unused variable. r166607: Add some cleanup to the DataLayout changes requested by Chandler. r166596: Revert "Back out r166591, not sure why this made it through since I cancelled the command. Bleh, sorry about this! r166591: Delete a directory that wasn't supposed to be checked in yet. r166578: Add in support for getIntPtrType to get the pointer type based on the address space. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167221 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-01 08:07:29 +00:00
LLVMContext &Context)
: TD(TD), TLI(TLI), Context(Context), Builder(Context, TargetFolder(TD)) {
Revert the series of commits starting with r166578 which introduced the getIntPtrType support for multiple address spaces via a pointer type, and also introduced a crasher bug in the constant folder reported in PR14233. These commits also contained several problems that should really be addressed before they are re-committed. I have avoided reverting various cleanups to the DataLayout APIs that are reasonable to have moving forward in order to reduce the amount of churn, and minimize the number of commits that were reverted. I've also manually updated merge conflicts and manually arranged for the getIntPtrType function to stay in DataLayout and to be defined in a plausible way after this revert. Thanks to Duncan for working through this exact strategy with me, and Nick Lewycky for tracking down the really annoying crasher this triggered. (Test case to follow in its own commit.) After discussing with Duncan extensively, and based on a note from Micah, I'm going to continue to back out some more of the more problematic patches in this series in order to ensure we go into the LLVM 3.2 branch with a reasonable story here. I'll send a note to llvmdev explaining what's going on and why. Summary of reverted revisions: r166634: Fix a compiler warning with an unused variable. r166607: Add some cleanup to the DataLayout changes requested by Chandler. r166596: Revert "Back out r166591, not sure why this made it through since I cancelled the command. Bleh, sorry about this! r166591: Delete a directory that wasn't supposed to be checked in yet. r166578: Add in support for getIntPtrType to get the pointer type based on the address space. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167221 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-01 08:07:29 +00:00
IntTy = TD->getIntPtrType(Context);
Zero = ConstantInt::get(IntTy, 0);
}
SizeOffsetEvalType ObjectSizeOffsetEvaluator::compute(Value *V) {
SizeOffsetEvalType Result = compute_(V);
if (!bothKnown(Result)) {
// erase everything that was computed in this iteration from the cache, so
// that no dangling references are left behind. We could be a bit smarter if
// we kept a dependency graph. It's probably not worth the complexity.
for (PtrSetTy::iterator I=SeenVals.begin(), E=SeenVals.end(); I != E; ++I) {
CacheMapTy::iterator CacheIt = CacheMap.find(*I);
// non-computable results can be safely cached
if (CacheIt != CacheMap.end() && anyKnown(CacheIt->second))
CacheMap.erase(CacheIt);
}
}
SeenVals.clear();
return Result;
}
SizeOffsetEvalType ObjectSizeOffsetEvaluator::compute_(Value *V) {
ObjectSizeOffsetVisitor Visitor(TD, TLI, Context);
SizeOffsetType Const = Visitor.compute(V);
if (Visitor.bothKnown(Const))
return std::make_pair(ConstantInt::get(Context, Const.first),
ConstantInt::get(Context, Const.second));
V = V->stripPointerCasts();
// check cache
CacheMapTy::iterator CacheIt = CacheMap.find(V);
if (CacheIt != CacheMap.end())
return CacheIt->second;
// always generate code immediately before the instruction being
// processed, so that the generated code dominates the same BBs
Instruction *PrevInsertPoint = Builder.GetInsertPoint();
if (Instruction *I = dyn_cast<Instruction>(V))
Builder.SetInsertPoint(I);
// record the pointers that were handled in this run, so that they can be
// cleaned later if something fails
SeenVals.insert(V);
// now compute the size and offset
SizeOffsetEvalType Result;
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
Result = visitGEPOperator(*GEP);
} else if (Instruction *I = dyn_cast<Instruction>(V)) {
Result = visit(*I);
} else if (isa<Argument>(V) ||
(isa<ConstantExpr>(V) &&
cast<ConstantExpr>(V)->getOpcode() == Instruction::IntToPtr) ||
isa<GlobalAlias>(V) ||
isa<GlobalVariable>(V)) {
// ignore values where we cannot do more than what ObjectSizeVisitor can
Result = unknown();
} else {
DEBUG(dbgs() << "ObjectSizeOffsetEvaluator::compute() unhandled value: "
<< *V << '\n');
Result = unknown();
}
if (PrevInsertPoint)
Builder.SetInsertPoint(PrevInsertPoint);
// Don't reuse CacheIt since it may be invalid at this point.
CacheMap[V] = Result;
return Result;
}
SizeOffsetEvalType ObjectSizeOffsetEvaluator::visitAllocaInst(AllocaInst &I) {
if (!I.getAllocatedType()->isSized())
return unknown();
// must be a VLA
assert(I.isArrayAllocation());
Value *ArraySize = I.getArraySize();
Value *Size = ConstantInt::get(ArraySize->getType(),
TD->getTypeAllocSize(I.getAllocatedType()));
Size = Builder.CreateMul(Size, ArraySize);
return std::make_pair(Size, Zero);
}
SizeOffsetEvalType ObjectSizeOffsetEvaluator::visitCallSite(CallSite CS) {
const AllocFnsTy *FnData = getAllocationData(CS.getInstruction(), AnyAlloc,
TLI);
if (!FnData)
return unknown();
// handle strdup-like functions separately
if (FnData->AllocTy == StrDupLike) {
// TODO
return unknown();
}
Value *FirstArg = CS.getArgument(FnData->FstParam);
FirstArg = Builder.CreateZExt(FirstArg, IntTy);
if (FnData->SndParam < 0)
return std::make_pair(FirstArg, Zero);
Value *SecondArg = CS.getArgument(FnData->SndParam);
SecondArg = Builder.CreateZExt(SecondArg, IntTy);
Value *Size = Builder.CreateMul(FirstArg, SecondArg);
return std::make_pair(Size, Zero);
// TODO: handle more standard functions (+ wchar cousins):
// - strdup / strndup
// - strcpy / strncpy
// - strcat / strncat
// - memcpy / memmove
// - strcat / strncat
// - memset
}
SizeOffsetEvalType
ObjectSizeOffsetEvaluator::visitExtractElementInst(ExtractElementInst&) {
return unknown();
}
SizeOffsetEvalType
ObjectSizeOffsetEvaluator::visitExtractValueInst(ExtractValueInst&) {
return unknown();
}
SizeOffsetEvalType
ObjectSizeOffsetEvaluator::visitGEPOperator(GEPOperator &GEP) {
SizeOffsetEvalType PtrData = compute_(GEP.getPointerOperand());
if (!bothKnown(PtrData))
return unknown();
Value *Offset = EmitGEPOffset(&Builder, *TD, &GEP, /*NoAssumptions=*/true);
Offset = Builder.CreateAdd(PtrData.second, Offset);
return std::make_pair(PtrData.first, Offset);
}
SizeOffsetEvalType ObjectSizeOffsetEvaluator::visitIntToPtrInst(IntToPtrInst&) {
// clueless
return unknown();
}
SizeOffsetEvalType ObjectSizeOffsetEvaluator::visitLoadInst(LoadInst&) {
return unknown();
}
SizeOffsetEvalType ObjectSizeOffsetEvaluator::visitPHINode(PHINode &PHI) {
// create 2 PHIs: one for size and another for offset
PHINode *SizePHI = Builder.CreatePHI(IntTy, PHI.getNumIncomingValues());
PHINode *OffsetPHI = Builder.CreatePHI(IntTy, PHI.getNumIncomingValues());
// insert right away in the cache to handle recursive PHIs
CacheMap[&PHI] = std::make_pair(SizePHI, OffsetPHI);
// compute offset/size for each PHI incoming pointer
for (unsigned i = 0, e = PHI.getNumIncomingValues(); i != e; ++i) {
Builder.SetInsertPoint(PHI.getIncomingBlock(i)->getFirstInsertionPt());
SizeOffsetEvalType EdgeData = compute_(PHI.getIncomingValue(i));
if (!bothKnown(EdgeData)) {
OffsetPHI->replaceAllUsesWith(UndefValue::get(IntTy));
OffsetPHI->eraseFromParent();
SizePHI->replaceAllUsesWith(UndefValue::get(IntTy));
SizePHI->eraseFromParent();
return unknown();
}
SizePHI->addIncoming(EdgeData.first, PHI.getIncomingBlock(i));
OffsetPHI->addIncoming(EdgeData.second, PHI.getIncomingBlock(i));
}
Value *Size = SizePHI, *Offset = OffsetPHI, *Tmp;
if ((Tmp = SizePHI->hasConstantValue())) {
Size = Tmp;
SizePHI->replaceAllUsesWith(Size);
SizePHI->eraseFromParent();
}
if ((Tmp = OffsetPHI->hasConstantValue())) {
Offset = Tmp;
OffsetPHI->replaceAllUsesWith(Offset);
OffsetPHI->eraseFromParent();
}
return std::make_pair(Size, Offset);
}
SizeOffsetEvalType ObjectSizeOffsetEvaluator::visitSelectInst(SelectInst &I) {
SizeOffsetEvalType TrueSide = compute_(I.getTrueValue());
SizeOffsetEvalType FalseSide = compute_(I.getFalseValue());
if (!bothKnown(TrueSide) || !bothKnown(FalseSide))
return unknown();
if (TrueSide == FalseSide)
return TrueSide;
Value *Size = Builder.CreateSelect(I.getCondition(), TrueSide.first,
FalseSide.first);
Value *Offset = Builder.CreateSelect(I.getCondition(), TrueSide.second,
FalseSide.second);
return std::make_pair(Size, Offset);
}
SizeOffsetEvalType ObjectSizeOffsetEvaluator::visitInstruction(Instruction &I) {
DEBUG(dbgs() << "ObjectSizeOffsetEvaluator unknown instruction:" << I <<'\n');
return unknown();
}