[PATCH] D127134: [llvm][DeadArgumentElimination] Add DW_CC_nocall to function metadata when all return values are removed

[David Blaikie via Phabricator via llvm-commits]

dblaikie added inline comments.


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Comment at: llvm/lib/Transforms/IPO/DeadArgumentElimination.cpp:1090-1091
+  // interpret the return value.
+  // FIXME: Should we add DW_CC_nocall simply when NFTy != FTy i.e. whenever
+  // an unused return value or an argument is removed?
+  if (!RetTy->isVoidTy() && NRetTy->isVoidTy() && NF->getSubprogram())
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I think this FIXME is correct, and we should probably just check if the type matches or not. Happy for that to go into this change rather than being a separate one - and if someone figures out some needle-threading nuance where the types might mismatch but still be call-compatible, they can add that back in later.


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Comment at: llvm/test/Transforms/DeadArgElim/2010-04-30-DbgInfo.ll:4-6
+; Test whether DW_CC_nocall calling convention is added when return values are removed and return type changed to void.
+; RUN: cat %t | grep "define internal fastcc void \@add_name_internal"
+; RUN: cat %t | grep DW_CC_nocall
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Generally we don't use 'grep' for tests in LLVM (very old pre-FileCheck tests use this sometimes, but we try to avoid doing it in new tests)

Please update these to use FileCheck (& you can probably leave the RUN line as-is, I think - without needing to introduce the %t and cat usage)


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D127134/new/

https://reviews.llvm.org/D127134