[clang] [llvm] RFC: Implementing new mechanism for hard register operands to inline asm as a constraint. (PR #85846)

[via cfe-commits]

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@@ -770,6 +770,18 @@ bool TargetInfo::validateOutputConstraint(ConstraintInfo &Info) const {
     case 'E':
     case 'F':
       break;  // Pass them.
+    case '{': {
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tltao wrote:

Yes, we should be using the same names. The register asm variable is parsed in `clang/lib/Sema/SemaDecl.cpp` using:
```
case SC_Register:
  // Local Named register
  if (!Context.getTargetInfo().isValidGCCRegisterName(Label) &&
      DeclAttrsMatchCUDAMode(getLangOpts(), getCurFunctionDecl()))
    Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label;
  break;
```


https://github.com/llvm/llvm-project/pull/85846