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-rw-r--r--lib/Analysis/MemoryBuiltins.cpp79
1 files changed, 51 insertions, 28 deletions
diff --git a/lib/Analysis/MemoryBuiltins.cpp b/lib/Analysis/MemoryBuiltins.cpp
index 5b2313e..f88affb 100644
--- a/lib/Analysis/MemoryBuiltins.cpp
+++ b/lib/Analysis/MemoryBuiltins.cpp
@@ -13,19 +13,19 @@
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "memory-builtins"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/STLExtras.h"
#include "llvm/Analysis/MemoryBuiltins.h"
-#include "llvm/GlobalVariable.h"
-#include "llvm/Instructions.h"
-#include "llvm/Intrinsics.h"
-#include "llvm/Metadata.h"
-#include "llvm/Module.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/TargetData.h"
#include "llvm/Target/TargetLibraryInfo.h"
#include "llvm/Transforms/Utils/Local.h"
using namespace llvm;
@@ -190,7 +190,7 @@ const CallInst *llvm::extractMallocCall(const Value *I,
return isMallocLikeFn(I, TLI) ? dyn_cast<CallInst>(I) : 0;
}
-static Value *computeArraySize(const CallInst *CI, const TargetData *TD,
+static Value *computeArraySize(const CallInst *CI, const DataLayout *TD,
const TargetLibraryInfo *TLI,
bool LookThroughSExt = false) {
if (!CI)
@@ -220,7 +220,7 @@ static Value *computeArraySize(const CallInst *CI, const TargetData *TD,
/// 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 TargetData *TD,
+ const DataLayout *TD,
const TargetLibraryInfo *TLI) {
const CallInst *CI = extractMallocCall(I, TLI);
Value *ArraySize = computeArraySize(CI, TD, TLI);
@@ -281,7 +281,7 @@ Type *llvm::getMallocAllocatedType(const CallInst *CI,
/// 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 TargetData *TD,
+Value *llvm::getMallocArraySize(CallInst *CI, const DataLayout *TD,
const TargetLibraryInfo *TLI,
bool LookThroughSExt) {
assert(isMallocLikeFn(CI, TLI) && "getMallocArraySize and not malloc call");
@@ -341,7 +341,7 @@ const CallInst *llvm::isFreeCall(const Value *I, const TargetLibraryInfo *TLI) {
/// 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 TargetData *TD,
+bool llvm::getObjectSize(const Value *Ptr, uint64_t &Size, const DataLayout *TD,
const TargetLibraryInfo *TLI, bool RoundToAlign) {
if (!TD)
return false;
@@ -373,7 +373,7 @@ APInt ObjectSizeOffsetVisitor::align(APInt Size, uint64_t Align) {
return Size;
}
-ObjectSizeOffsetVisitor::ObjectSizeOffsetVisitor(const TargetData *TD,
+ObjectSizeOffsetVisitor::ObjectSizeOffsetVisitor(const DataLayout *TD,
const TargetLibraryInfo *TLI,
LLVMContext &Context,
bool RoundToAlign)
@@ -385,20 +385,27 @@ ObjectSizeOffsetVisitor::ObjectSizeOffsetVisitor(const TargetData *TD,
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))
+
+ if (isa<Instruction>(V) || isa<GEPOperator>(V)) {
+ // If we have already seen this instruction, bail out.
+ if (!SeenInsts.insert(V))
return unknown();
+ SizeOffsetType Ret;
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V))
- return visitGEPOperator(*GEP);
- return visit(*I);
+ Ret = visitGEPOperator(*GEP);
+ else
+ Ret = visit(cast<Instruction>(*V));
+ SeenInsts.erase(V);
+ return Ret;
}
+
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))
@@ -406,8 +413,6 @@ SizeOffsetType ObjectSizeOffsetVisitor::compute(Value *V) {
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
@@ -510,14 +515,19 @@ ObjectSizeOffsetVisitor::visitExtractValueInst(ExtractValueInst&) {
SizeOffsetType ObjectSizeOffsetVisitor::visitGEPOperator(GEPOperator &GEP) {
SizeOffsetType PtrData = compute(GEP.getPointerOperand());
- if (!bothKnown(PtrData) || !GEP.hasAllConstantIndices())
+ APInt Offset(IntTyBits, 0);
+ if (!bothKnown(PtrData) || !GEP.accumulateConstantOffset(*TD, Offset))
return unknown();
- SmallVector<Value*, 8> Ops(GEP.idx_begin(), GEP.idx_end());
- APInt Offset(IntTyBits,TD->getIndexedOffset(GEP.getPointerOperandType(),Ops));
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();
@@ -536,9 +546,21 @@ SizeOffsetType ObjectSizeOffsetVisitor::visitLoadInst(LoadInst&) {
return unknown();
}
-SizeOffsetType ObjectSizeOffsetVisitor::visitPHINode(PHINode&) {
- // too complex to analyze statically.
- return unknown();
+SizeOffsetType ObjectSizeOffsetVisitor::visitPHINode(PHINode &PHI) {
+ if (PHI.getNumIncomingValues() == 0)
+ return unknown();
+
+ SizeOffsetType Ret = compute(PHI.getIncomingValue(0));
+ if (!bothKnown(Ret))
+ return unknown();
+
+ // verify that all PHI incoming pointers have the same size and offset
+ for (unsigned i = 1, e = PHI.getNumIncomingValues(); i != e; ++i) {
+ SizeOffsetType EdgeData = compute(PHI.getIncomingValue(i));
+ if (!bothKnown(EdgeData) || EdgeData != Ret)
+ return unknown();
+ }
+ return Ret;
}
SizeOffsetType ObjectSizeOffsetVisitor::visitSelectInst(SelectInst &I) {
@@ -559,7 +581,7 @@ SizeOffsetType ObjectSizeOffsetVisitor::visitInstruction(Instruction &I) {
}
-ObjectSizeOffsetEvaluator::ObjectSizeOffsetEvaluator(const TargetData *TD,
+ObjectSizeOffsetEvaluator::ObjectSizeOffsetEvaluator(const DataLayout *TD,
const TargetLibraryInfo *TLI,
LLVMContext &Context)
: TD(TD), TLI(TLI), Context(Context), Builder(Context, TargetFolder(TD)) {
@@ -619,6 +641,7 @@ SizeOffsetEvalType ObjectSizeOffsetEvaluator::compute_(Value *V) {
} 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();
generated by cgit v1.1 at 2025-11-11 07:37:19 +0000