[clang] [Clang]Throw frontend error for target feature mismatch when using `flatten` attribute (PR #150044)

[Abhishek Kaushik via cfe-commits]

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@@ -5232,9 +5232,11 @@ RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
     // since otherwise we could be making a conditional call after a check for
     // the proper cpu features (and it won't cause code generation issues due to
     // function based code generation).
-    if (TargetDecl->hasAttr<AlwaysInlineAttr>() &&
-        (TargetDecl->hasAttr<TargetAttr>() ||
-         (CurFuncDecl && CurFuncDecl->hasAttr<TargetAttr>())))
+    if ((TargetDecl->hasAttr<AlwaysInlineAttr>() &&
+         (TargetDecl->hasAttr<TargetAttr>() ||
+          (CurFuncDecl && CurFuncDecl->hasAttr<TargetAttr>()))) ||
+        (CurFuncDecl && CurFuncDecl->hasAttr<FlattenAttr>() &&
+         TargetDecl->hasAttr<TargetAttr>()))
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abhishek-kaushik22 wrote:

Thank You! I was not considering the fact that we can also disable features using the target attribute. I've added the condition and a new test for this.

https://github.com/llvm/llvm-project/pull/150044