BoundsChecking: add support for ConstantPointerNull. fixes a bunch of instrumentation failures in loops with reallocs

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158210 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nuno Lopes 2012-06-08 16:31:42 +00:00
parent 7c18922f85
commit eb90adffe1

View File

@ -377,11 +377,13 @@ bool BoundsChecking::computeAllocSize(Value *Ptr, APInt &Offset,
}
RETURN(true);
// TODO: handle more standard functions:
// TODO: handle more standard functions (+ wchar cousins):
// - strdup / strndup
// - strcpy / strncpy
// - strcat / strncat
// - memcpy / memmove
// - strcat / strncat
// - memset
} else if (PHINode *PHI = dyn_cast<PHINode>(Ptr)) {
// create 2 PHIs: one for offset and another for size
@ -389,8 +391,7 @@ bool BoundsChecking::computeAllocSize(Value *Ptr, APInt &Offset,
PHINode *SizePHI = Builder->CreatePHI(IntTy, PHI->getNumIncomingValues());
// insert right away in the cache to handle recursive PHIs
CacheData CacheEntry(APInt(), OffsetPHI, APInt(), SizePHI, true);
CacheMap[Ptr] = CacheEntry;
CacheMap[Ptr] = CacheData(APInt(), OffsetPHI, APInt(), SizePHI, true);
// compute offset/size for each PHI incoming pointer
for (unsigned i = 0, e = PHI->getNumIncomingValues(); i != e; ++i) {
@ -419,7 +420,7 @@ bool BoundsChecking::computeAllocSize(Value *Ptr, APInt &Offset,
SizeValue = SizePHI;
RETURN(true);
} else if (isa<UndefValue>(Ptr)) {
} else if (isa<UndefValue>(Ptr) || isa<ConstantPointerNull>(Ptr)) {
Size = 0;
RETURN(true);
@ -428,12 +429,12 @@ bool BoundsChecking::computeAllocSize(Value *Ptr, APInt &Offset,
RETURN(false);
}
DEBUG(dbgs() << "computeAllocSize unhandled value:\n" << *Ptr << "\n");
RETURN(false);
cache_and_return:
// cache the result and return
CacheData CacheEntry(Offset, OffsetValue, Size, SizeValue, ReturnVal);
CacheMap[Ptr] = CacheEntry;
CacheMap[Ptr] = CacheData(Offset, OffsetValue, Size, SizeValue, ReturnVal);
// non-computable results can be safely cached
if (!ReturnVal)