[PATCH] D89191: [ASAN] Make sure we are only processing lifetime markers with offset 0 to alloca

[Vitaly Buka via Phabricator via llvm-commits]

vitalybuka added inline comments.


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Comment at: llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp:1083
+    // beginning of the alloca.
+    AllocaInst *AI = findAllocaForValue(II.getArgOperand(1), true);
     if (!AI) {
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lxfind wrote:
> lxfind wrote:
> > vitalybuka wrote:
> > > Similar problem is if the size of lifetime is smaller then alloca.
> > > Would you like to handle that case, here or in the another patch? 
> > Is that a problem though? A lifetime marker should always be accurate, that is, if the marker indicates that only part of the region is alive, it should be ok to just mark that region alive?
> I will land this as it is for now. But please do let me know your thoughts on what we want to do when the size doesn't match.
if marker can point with offset, skipping the beginning of the alloca, then I assume sooner or later something may generate code which will set size smaller then alloca, skipping the tail of it.


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  https://reviews.llvm.org/D89191/new/

https://reviews.llvm.org/D89191