[clang] [llvm] [Clang][SME] Detect always_inline used with mismatched streaming attributes (PR #77936)

[Sander de Smalen via cfe-commits]

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@@ -814,6 +820,43 @@ Address AArch64ABIInfo::EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
                           /*allowHigherAlign*/ false);
 }
 
+static bool isStreaming(const FunctionDecl *F) {
+  if (F->hasAttr<ArmLocallyStreamingAttr>())
+    return true;
+  if (const auto *T = F->getType()->getAs<FunctionProtoType>())
+    return T->getAArch64SMEAttributes() & FunctionType::SME_PStateSMEnabledMask;
+  return false;
+}
+
+static bool isStreamingCompatible(const FunctionDecl *F) {
+  if (const auto *T = F->getType()->getAs<FunctionProtoType>())
+    return T->getAArch64SMEAttributes() &
+           FunctionType::SME_PStateSMCompatibleMask;
+  return false;
+}
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sdesmalen-arm wrote:

Yes it makes sense to create a single interface for these and remove any duplicates!

I think we'll want to have two interfaces:
* One for QualType for the type attributes (declared in AST/Type.h?)
* One for FunctionDecl that also checks the declaration attributes (declared in AST/Decl.h?)

I'm happy for it to be done as part of this patch or as a follow-up to keep this patch simpler.

https://github.com/llvm/llvm-project/pull/77936