[clang] [clang][FMV][AArch64] Improve streaming mode compatibility. (PR #100181)

[Sander de Smalen via cfe-commits]

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@@ -3183,6 +3183,25 @@ class ASTContext : public RefCountedBase<ASTContext> {
       const FunctionDecl *FD,
       llvm::function_ref<void(FunctionDecl *)> Pred) const;
 
+  bool areFMVCompatible(const FunctionDecl *FD1,
+                        const FunctionDecl *FD2) const {
+    if (!hasSameType(FD1->getReturnType(), FD2->getReturnType()))
+      return false;
+
+    if (FD1->isVariadic() != FD2->isVariadic())
+      return false;
+
+    if (FD1->getNumParams() != FD2->getNumParams())
+      return false;
+
+    for (unsigned I = 0; I < FD1->getNumParams(); ++I)
+      if (!hasSameType(FD1->getParamDecl(I)->getOriginalType(),
+                       FD2->getParamDecl(I)->getOriginalType()))
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sdesmalen-arm wrote:

Is there a test (missing) for this condition?

https://github.com/llvm/llvm-project/pull/100181