[PATCH] D102153: [SelectionDAG] Fix argument copy elision with irregular types

[Reid Kleckner via Phabricator via llvm-commits]

rnk added a comment.

I don't see why this optimization should be declared illegal. Why isn't it the caller's responsibility to store these narrow integers canonically? C doesn't have narrow integers, but GCC doesn't do this. If a variable is passed in memory, it just uses the memory that was passed into it.



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Comment at: llvm/test/CodeGen/X86/arg-copy-elide.ll:80
+; CHECK-NEXT:    andb $1, %al
+; CHECK-NEXT:    movb %al, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    leal {{[0-9]+}}(%esp), %eax
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We don't want this, do we? Seems like it would be a regression.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D102153/new/

https://reviews.llvm.org/D102153