#include "llvm/Constants.h"
#include "llvm/Instructions.h"
#include "llvm/Module.h"
-#include "llvm/Analysis/ConstantFolding.h"
+#include "llvm/Analysis/ValueTracking.h"
+#include "llvm/Target/TargetData.h"
using namespace llvm;
//===----------------------------------------------------------------------===//
// malloc Call Utility Functions.
//
-/// isMalloc - Returns true if the the value is either a malloc call or a
+/// isMalloc - Returns true if the value is either a malloc call or a
/// bitcast of the result of a malloc call.
bool llvm::isMalloc(const Value *I) {
return extractMallocCall(I) || extractMallocCallFromBitCast(I);
if (!CI)
return false;
- const Module *M = CI->getParent()->getParent()->getParent();
- Function *MallocFunc = M->getFunction("malloc");
-
- if (CI->getOperand(0) != MallocFunc)
+ Function *Callee = CI->getCalledFunction();
+ if (Callee == 0 || !Callee->isDeclaration())
+ return false;
+ if (Callee->getName() != "malloc" &&
+ Callee->getName() != "_Znwj" && // operator new(unsigned int)
+ Callee->getName() != "_Znwm" && // operator new(unsigned long)
+ Callee->getName() != "_Znaj" && // operator new[](unsigned int)
+ Callee->getName() != "_Znam") // operator new[](unsigned long)
return false;
// Check malloc prototype.
// FIXME: workaround for PR5130, this will be obsolete when a nobuiltin
// attribute will exist.
- const FunctionType *FTy = MallocFunc->getFunctionType();
+ FunctionType *FTy = Callee->getFunctionType();
if (FTy->getNumParams() != 1)
return false;
- if (IntegerType *ITy = dyn_cast<IntegerType>(FTy->param_begin()->get())) {
- if (ITy->getBitWidth() != 32 && ITy->getBitWidth() != 64)
- return false;
- return true;
- }
-
- return false;
+ return FTy->getParamType(0)->isIntegerTy(32) ||
+ FTy->getParamType(0)->isIntegerTy(64);
}
/// extractMallocCall - Returns the corresponding CallInst if the instruction
: NULL;
}
-/// isConstantOne - Return true only if val is constant int 1.
-static bool isConstantOne(Value *val) {
- return isa<ConstantInt>(val) && cast<ConstantInt>(val)->isOne();
-}
-
-static Value *isArrayMallocHelper(const CallInst *CI, LLVMContext &Context,
- const TargetData *TD) {
+static Value *computeArraySize(const CallInst *CI, const TargetData *TD,
+ bool LookThroughSExt = false) {
if (!CI)
return NULL;
- // Type must be known to determine array size.
- const Type *T = getMallocAllocatedType(CI);
- if (!T)
- return NULL;
-
- Value *MallocArg = CI->getOperand(1);
- ConstantExpr *CO = dyn_cast<ConstantExpr>(MallocArg);
- BinaryOperator *BO = dyn_cast<BinaryOperator>(MallocArg);
-
- Constant *ElementSize = ConstantExpr::getSizeOf(T);
- ElementSize = ConstantExpr::getTruncOrBitCast(ElementSize,
- MallocArg->getType());
- Constant *FoldedElementSize =
- ConstantFoldConstantExpression(cast<ConstantExpr>(ElementSize), Context, TD);
-
- // First, check if CI is a non-array malloc.
- if (CO && ((CO == ElementSize) ||
- (FoldedElementSize && (CO == FoldedElementSize))))
- // Match CreateMalloc's use of constant 1 array-size for non-array mallocs.
- return ConstantInt::get(MallocArg->getType(), 1);
-
- // Second, check if CI is an array malloc whose array size can be determined.
- if (isConstantOne(ElementSize) ||
- (FoldedElementSize && isConstantOne(FoldedElementSize)))
- return MallocArg;
-
- if (!CO && !BO)
+ // The size of the malloc's result type must be known to determine array size.
+ Type *T = getMallocAllocatedType(CI);
+ if (!T || !T->isSized() || !TD)
return NULL;
- Value *Op0 = NULL;
- Value *Op1 = NULL;
- unsigned Opcode = 0;
- if (CO && ((CO->getOpcode() == Instruction::Mul) ||
- (CO->getOpcode() == Instruction::Shl))) {
- Op0 = CO->getOperand(0);
- Op1 = CO->getOperand(1);
- Opcode = CO->getOpcode();
- }
- if (BO && ((BO->getOpcode() == Instruction::Mul) ||
- (BO->getOpcode() == Instruction::Shl))) {
- Op0 = BO->getOperand(0);
- Op1 = BO->getOperand(1);
- Opcode = BO->getOpcode();
- }
+ unsigned ElementSize = TD->getTypeAllocSize(T);
+ if (StructType *ST = dyn_cast<StructType>(T))
+ ElementSize = TD->getStructLayout(ST)->getSizeInBytes();
- // Determine array size if malloc's argument is the product of a mul or shl.
- if (Op0) {
- if (Opcode == Instruction::Mul) {
- if ((Op1 == ElementSize) ||
- (FoldedElementSize && (Op1 == FoldedElementSize)))
- // ArraySize * ElementSize
- return Op0;
- if ((Op0 == ElementSize) ||
- (FoldedElementSize && (Op0 == FoldedElementSize)))
- // ElementSize * ArraySize
- return Op1;
- }
- if (Opcode == Instruction::Shl) {
- ConstantInt *Op1CI = dyn_cast<ConstantInt>(Op1);
- if (!Op1CI) return NULL;
-
- APInt Op1Int = Op1CI->getValue();
- uint64_t BitToSet = Op1Int.getLimitedValue(Op1Int.getBitWidth() - 1);
- Value *Op1Pow = ConstantInt::get(Context,
- APInt(Op1Int.getBitWidth(), 0).set(BitToSet));
- if (Op0 == ElementSize || (FoldedElementSize && Op0 == FoldedElementSize))
- // ArraySize << log2(ElementSize)
- return Op1Pow;
- if (Op1Pow == ElementSize ||
- (FoldedElementSize && Op1Pow == FoldedElementSize))
- // ElementSize << log2(ArraySize)
- return Op0;
- }
- }
+ // 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 = NULL;
+ if (ComputeMultiple(MallocArg, ElementSize, Multiple,
+ LookThroughSExt))
+ return Multiple;
- // We could not determine the malloc array size from MallocArg.
return NULL;
}
/// 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.
-CallInst *llvm::isArrayMalloc(Value *I, LLVMContext &Context,
- const TargetData *TD) {
- CallInst *CI = extractMallocCall(I);
- Value *ArraySize = isArrayMallocHelper(CI, Context, TD);
-
- if (ArraySize &&
- ArraySize != ConstantInt::get(CI->getOperand(1)->getType(), 1))
- return CI;
-
- // CI is a non-array malloc or we can't figure out that it is an array malloc.
- return NULL;
-}
-
-const CallInst *llvm::isArrayMalloc(const Value *I, LLVMContext &Context,
- const TargetData *TD) {
+const CallInst *llvm::isArrayMalloc(const Value *I, const TargetData *TD) {
const CallInst *CI = extractMallocCall(I);
- Value *ArraySize = isArrayMallocHelper(CI, Context, TD);
+ Value *ArraySize = computeArraySize(CI, TD);
if (ArraySize &&
- ArraySize != ConstantInt::get(CI->getOperand(1)->getType(), 1))
+ ArraySize != ConstantInt::get(CI->getArgOperand(0)->getType(), 1))
return CI;
// CI is a non-array malloc or we can't figure out that it is an array malloc.
}
/// getMallocType - Returns the PointerType resulting from the malloc call.
-/// This PointerType is the result type of the call's only bitcast use.
-/// If there is no unique bitcast use, then return NULL.
-const PointerType *llvm::getMallocType(const CallInst *CI) {
- assert(isMalloc(CI) && "GetMallocType and not malloc call");
-
- const BitCastInst *BCI = NULL;
+/// 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) {
+ assert(isMalloc(CI) && "getMallocType and not malloc call");
+ PointerType *MallocType = NULL;
+ unsigned NumOfBitCastUses = 0;
+
// Determine if CallInst has a bitcast use.
- for (Value::use_const_iterator UI = CI->use_begin(), E = CI->use_end();
+ for (Value::const_use_iterator UI = CI->use_begin(), E = CI->use_end();
UI != E; )
- if ((BCI = dyn_cast<BitCastInst>(cast<Instruction>(*UI++))))
- break;
+ if (const BitCastInst *BCI = dyn_cast<BitCastInst>(*UI++)) {
+ MallocType = cast<PointerType>(BCI->getDestTy());
+ NumOfBitCastUses++;
+ }
- // Malloc call has 1 bitcast use and no other uses, so type is the bitcast's
- // destination type.
- if (BCI && CI->hasOneUse())
- return cast<PointerType>(BCI->getDestTy());
+ // 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.
- if (!BCI)
+ if (NumOfBitCastUses == 0)
return cast<PointerType>(CI->getType());
// Type could not be determined.
return NULL;
}
-/// getMallocAllocatedType - Returns the Type allocated by malloc call. This
-/// Type is the result type of the call's only bitcast use. If there is no
-/// unique bitcast use, then return NULL.
-const Type *llvm::getMallocAllocatedType(const CallInst *CI) {
- const PointerType *PT = getMallocType(CI);
+/// 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) {
+ PointerType *PT = getMallocType(CI);
return PT ? PT->getElementType() : NULL;
}
/// 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, LLVMContext &Context,
- const TargetData *TD) {
- return isArrayMallocHelper(CI, Context, TD);
+Value *llvm::getMallocArraySize(CallInst *CI, const TargetData *TD,
+ bool LookThroughSExt) {
+ assert(isMalloc(CI) && "getMallocArraySize and not malloc call");
+ return computeArraySize(CI, TD, LookThroughSExt);
}
//===----------------------------------------------------------------------===//
// free Call Utility Functions.
//
-/// isFreeCall - Returns true if the the value is a call to the builtin free()
-bool llvm::isFreeCall(const Value *I) {
+/// isFreeCall - Returns non-null if the value is a call to the builtin free()
+const CallInst *llvm::isFreeCall(const Value *I) {
const CallInst *CI = dyn_cast<CallInst>(I);
if (!CI)
- return false;
+ return 0;
+ Function *Callee = CI->getCalledFunction();
+ if (Callee == 0 || !Callee->isDeclaration())
+ return 0;
- const Module *M = CI->getParent()->getParent()->getParent();
- Function *FreeFunc = M->getFunction("free");
-
- if (CI->getOperand(0) != FreeFunc)
- return false;
+ if (Callee->getName() != "free" &&
+ Callee->getName() != "_ZdlPv" && // operator delete(void*)
+ Callee->getName() != "_ZdaPv") // operator delete[](void*)
+ return 0;
// Check free prototype.
// FIXME: workaround for PR5130, this will be obsolete when a nobuiltin
// attribute will exist.
- const FunctionType *FTy = FreeFunc->getFunctionType();
- if (FTy->getReturnType() != Type::getVoidTy(M->getContext()))
- return false;
+ FunctionType *FTy = Callee->getFunctionType();
+ if (!FTy->getReturnType()->isVoidTy())
+ return 0;
if (FTy->getNumParams() != 1)
- return false;
- if (FTy->param_begin()->get() != Type::getInt8PtrTy(M->getContext()))
- return false;
+ return 0;
+ if (FTy->getParamType(0) != Type::getInt8PtrTy(Callee->getContext()))
+ return 0;
- return true;
+ return CI;
}