[clang] [X86][CFE] Support EGPR in inline assembly. (PR #91323)

[Shengchen Kan via cfe-commits]

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@@ -1763,10 +1823,14 @@ void X86TargetInfo::fillValidTuneCPUList(SmallVectorImpl<StringRef> &Values) con
 }
 
 ArrayRef<const char *> X86TargetInfo::getGCCRegNames() const {
+  if (HasEGPR)
+    return llvm::ArrayRef(ExtendedGCCRegNames);
   return llvm::ArrayRef(GCCRegNames);
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KanRobert wrote:

It's a gap. https://www.godbolt.org/z/xx8nrMdYW
But please keep the behavior consistent inside clang

https://github.com/llvm/llvm-project/pull/91323