[llvm] [clang] [PowerPC][X86] Make cpu id builtins target independent and lower for PPC (PR #68919)

[Amy Kwan via llvm-commits]

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@@ -2110,6 +2110,66 @@ static bool checkFPMathBuiltinElementType(Sema &S, SourceLocation Loc,
   return false;
 }
 
+/// SemaBuiltinCpuSupports - Handle __builtin_cpu_supports(char *).
+/// This checks that the target supports __builtin_cpu_supports and
+/// that the string argument is constant and valid.
+static bool SemaBuiltinCpuSupports(Sema &S, const TargetInfo &TI,
+                                   const TargetInfo *AuxTI, CallExpr *TheCall) {
+  Expr *Arg = TheCall->getArg(0);
+
+  const TargetInfo *TheTI = nullptr;
+  if (TI.supportsCpuSupports())
+    TheTI = &TI;
+  else if (AuxTI && AuxTI->supportsCpuSupports())
+    TheTI = AuxTI;
+  else
+    return S.Diag(TheCall->getBeginLoc(), diag::err_builtin_target_unsupported)
+           << SourceRange(TheCall->getBeginLoc(), TheCall->getEndLoc());
+
+  // Check if the argument is a string literal.
+  if (!isa<StringLiteral>(Arg->IgnoreParenImpCasts()))
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amy-kwan wrote:

It seems like we can pull out some of the calls are are repeated, such as `Arg->IgnoreParenImpCasts()`.

https://github.com/llvm/llvm-project/pull/68919