[PATCH] D151863: [x86][MC] Fix movdir64b addressing

[Kan Shengchen via Phabricator via llvm-commits]

skan added inline comments.


================
Comment at: llvm/test/MC/X86/x86-64-movdir64b-intel.s:1
+// RUN: llvm-mc -triple x86_64-unknown-unknown -x86-asm-syntax=intel -output-asm-variant=1 --show-encoding %s | FileCheck %s
+// CHECK: movdir64b rax, zmmword ptr [rax - 4096]
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akshaykhadse wrote:
> skan wrote:
> > The test can pass w/o this patch. I think we should replace it with IR test (llc) here, the input should be the diff in ms-inline-asm-64.c.
> It is better to remove this as it does not add any value.
> 
> We cannot write a llc test for this because:
>   - If input IR is `call ... "movdir64b eax, ZMMWORD PTR arr ..."`, the generated assembly will be `movdir64b arr, %rax"
>   - If input IR is `call ... "movdir64b eax, ZMMWORD PTR $0 ..."`, the generated assembly will be `movdir64b -4016(%rbp), %rax"
> 
> In other words, it's responsibility of front-end to generate the correct IR. If the IR is not correct, the back-end will not fix it and incorrect assembly will be generated.
> 
The backend will parse the inline asm in IR too. As I mentioned, you split the end-to-end test to C->IR and IR->AS. So you need to check the inline asm in IR can be parsed correctly.


Repository:
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https://reviews.llvm.org/D151863