[PATCH] D129727: [ARM64EC 11/?] Add support for lowering variadic indirect calls.

Mon Sep 26 12:34:50 PDT 2022

efriedma added inline comments.

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Comment at: llvm/lib/Target/AArch64/AArch64ISelLowering.cpp:1467
+    setLibcallName(RTLIB::MEMSET, "#memset");
+    setLibcallName(RTLIB::MEMMOVE, "#memmove");
+  }
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bcl5980 wrote:
> efriedma wrote:
> > Is this actually necessary?  The linker should resolve plain "memcpy" to something reasonable, I think.
> Based on my local test, if I don't add `#` the memcpy will be link into x86 version memcpy and crash at runtime.
Does the linking process for arm64ec actually guarantee that we have an arm64ec msvcrt that includes "#memcpy" etc.?  Even if it does, I don't think we can make the same assumption for all the other functions SelectionDAG needs to call.

Given that, we're going to need some mechanism to allow calls generated by SelectionDAG to participate in thunking.

In any case, if this change unblocks testing for you, we can leave it in with a FIXME to address the above.

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D129727/new/

https://reviews.llvm.org/D129727