[llvm] [AMDGPU] Add an asm directive to track code_object_version (PR #76267)

[Konstantin Zhuravlyov via llvm-commits]

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@@ -123,45 +124,32 @@ bool isHsaAbi(const MCSubtargetInfo &STI) {
   return STI.getTargetTriple().getOS() == Triple::AMDHSA;
 }
 
-std::optional<uint8_t> getHsaAbiVersion(const MCSubtargetInfo *STI) {
-  if (STI && STI->getTargetTriple().getOS() != Triple::AMDHSA)
-    return std::nullopt;
-
-  switch (AmdhsaCodeObjectVersion) {
-  case 4:
-    return ELF::ELFABIVERSION_AMDGPU_HSA_V4;
-  case 5:
-    return ELF::ELFABIVERSION_AMDGPU_HSA_V5;
-  default:
-    report_fatal_error(Twine("Unsupported AMDHSA Code Object Version ") +
-                       Twine(AmdhsaCodeObjectVersion));
+unsigned getCodeObjectVersion(const Module &M) {
+  if (auto Ver = mdconst::extract_or_null<ConstantInt>(
+          M.getModuleFlag("amdgpu_code_object_version"))) {
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kzhuravl wrote:

This is HSA-specific version only used with ELFOSABI_AMDGPU_HSA. See e_ident[EI_ABIVERSION] row in https://llvm.org/docs/AMDGPUUsage.html#amdgpu-elf-header-table. So I think it would be good to clean this up and have consistent naming, with amdhsa prefix in LLVM IR and ASM directive.

https://github.com/llvm/llvm-project/pull/76267