[PATCH] D136285: Bad optimization with alloca and intrinsic function stackrestore

[Reid Kleckner via Phabricator via llvm-commits]

rnk added inline comments.


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Comment at: llvm/test/Transforms/MemCpyOpt/stackrestore.ll:97
+  %SS = tail call ptr @llvm.stacksave()
+  %A2 = alloca [56 x i8], align 4
+  store i8 1, ptr %A2, align 4
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My expectation is that all the allocas here are static: They are part of the entry block, they will be part of the initial stack allocation, they will not be affected by stacksave/restore. This does mean that simplifycfg can extend the lifetime of a stack allocation, but to my knowledge, that's valid, the program should have the same observable behavior.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D136285/new/

https://reviews.llvm.org/D136285