[clang] [SPARC][clang] Add -m(no-)v8plus flags handling (PR #98713)

[via cfe-commits]

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@@ -179,6 +179,13 @@ void sparc::getSparcTargetFeatures(const Driver &D, const ArgList &Args,
       Features.push_back("-hard-quad-float");
   }
 
+  if (Arg *A = Args.getLastArg(options::OPT_mv8plus, options::OPT_mno_v8plus)) {
+    if (A->getOption().matches(options::OPT_mv8plus))
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koachan wrote:

Ah, I see.
In that case, would making these a no-op flag okay for now? As far as I understand it that would still be a compliant implementation, no? Codegen, etc. changes will happen in future patches but I can amend this one to include a placeholder `v8plus` feature bit in the backend.

What do you think about it?

(Some background: I am currently only looking to include this in clang because Linux passes `-mv8plus` when building 32-bit objects since some of its inline asm uses 64-bit registers, but otherwise it doesn't care if compiler-generated code uses them or not)

https://github.com/llvm/llvm-project/pull/98713