[clang] [AIX] recognize vsr in inline asm for AIX (PR #68476)

[Stefan Pintilie via cfe-commits]

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@@ -828,10 +829,7 @@ const TargetInfo::AddlRegName GCCAddlRegNames[] = {
 };
 
 ArrayRef<TargetInfo::AddlRegName> PPCTargetInfo::getGCCAddlRegNames() const {
-  if (ABI == "elfv2")
-    return llvm::ArrayRef(GCCAddlRegNames);
-  else
-    return TargetInfo::getGCCAddlRegNames();
+  return llvm::ArrayRef(GCCAddlRegNames);
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stefanp-ibm wrote:

This blanket addition of the vs registers for all ABIs makes me a little nervous. I'm not sure that all ABIs will (or do) support these registers. For example, we support ELFv1 but based on this: https://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.html#REG
I'm not sure it supports the vs registers.

Since we are doing this for AIX it may be safer just to explicitly mention XCOFF.

https://github.com/llvm/llvm-project/pull/68476