[PATCH] D78659: Add nomerge function attribute to supress tail merge optimization in simplifyCFG

[Zequan Wu via Phabricator via cfe-commits]

zequanwu marked an inline comment as done.
zequanwu added inline comments.


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Comment at: llvm/lib/Transforms/Utils/SimplifyCFG.cpp:1305
+    if (const auto *CB1 = dyn_cast<CallBase>(I1))
+      if (CB1->cannotMerge())
+        return Changed;
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rnk wrote:
> It seems inconsistent that we don't apply the same logic to inline asm here. I think you should modify `cannotMerge` to return `isInlineAsm() || hasFnAttr(...NoMerge)`, and then remove the isInlineAsm case below.
This changes breaks the test `AArch64/arm64-shrink-wrapping.ll` because the inlineAsm cannot be deleted. I think we should only check for `hasFnAttr(NoMerge)` for `CB1` and `CB2`.


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https://reviews.llvm.org/D78659