Revert r176408 and r176407 to address PR15540.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179111 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nadav Rotem
2013-04-09 18:16:05 +00:00
parent b976e407dc
commit 8e4df489d0
4 changed files with 43 additions and 189 deletions

View File

@ -364,26 +364,6 @@ bool llvm::getObjectSize(const Value *Ptr, uint64_t &Size, const DataLayout *TD,
return true;
}
/// \brief Compute the size of the underlying 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::getUnderlyingObjectSize(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.knownSize(Data))
return false;
Size = Data.first.getZExtValue();
return true;
}
STATISTIC(ObjectVisitorArgument,
"Number of arguments with unsolved size and offset");
@ -409,23 +389,16 @@ ObjectSizeOffsetVisitor::ObjectSizeOffsetVisitor(const DataLayout *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))
return unknown();
if (isa<Instruction>(V) || isa<GEPOperator>(V)) {
// Return cached value or insert unknown in cache if size of V was not
// computed yet in order to avoid recursions in PHis.
std::pair<CacheMapTy::iterator, bool> CacheVal =
CacheMap.insert(std::make_pair(V, unknown()));
if (!CacheVal.second)
return CacheVal.first->second;
SizeOffsetType Result;
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V))
Result = visitGEPOperator(*GEP);
else
Result = visit(cast<Instruction>(*V));
return CacheMap[V] = Result;
return visitGEPOperator(*GEP);
return visit(*I);
}
if (Argument *A = dyn_cast<Argument>(V))
return visitArgument(*A);
if (ConstantPointerNull *P = dyn_cast<ConstantPointerNull>(V))
@ -439,6 +412,8 @@ 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
@ -572,21 +547,9 @@ SizeOffsetType ObjectSizeOffsetVisitor::visitLoadInst(LoadInst&) {
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::visitPHINode(PHINode&) {
// too complex to analyze statically.
return unknown();
}
SizeOffsetType ObjectSizeOffsetVisitor::visitSelectInst(SelectInst &I) {