[clang] [AArch64] Warn when calling a NEON builtin in a streaming function (PR #73672)

[Sander de Smalen via cfe-commits]

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@@ -2993,6 +2993,62 @@ static QualType getNeonEltType(NeonTypeFlags Flags, ASTContext &Context,
   llvm_unreachable("Invalid NeonTypeFlag!");
 }
 
+enum ArmStreamingType {
+  ArmNonStreaming,
+  ArmStreaming,
+  ArmStreamingCompatible,
+  ArmLocallyStreaming,
+  ArmStreamingOrSVE2p1
+};
+
+static ArmStreamingType getArmStreamingFnType(const FunctionDecl *FD) {
+  if (FD->hasAttr<ArmLocallyStreamingAttr>())
+    return ArmLocallyStreaming;
+  if (const auto *T = FD->getType()->getAs<FunctionProtoType>()) {
+    if (T->getAArch64SMEAttributes() & FunctionType::SME_PStateSMEnabledMask)
+      return ArmStreaming;
+    if (T->getAArch64SMEAttributes() & FunctionType::SME_PStateSMCompatibleMask)
+      return ArmStreamingCompatible;
+  }
+  return ArmNonStreaming;
+}
+
+static void checkArmStreamingBuiltin(Sema &S, CallExpr *TheCall,
+                                     const FunctionDecl *FD,
+                                     ArmStreamingType BuiltinType) {
+  assert(BuiltinType != ArmLocallyStreaming &&
+         "Unexpected locally_streaming attribute for builtin!");
+
+  ArmStreamingType FnType = getArmStreamingFnType(FD);
+  if (BuiltinType == ArmStreamingOrSVE2p1) {
+    // Check intrinsics that are available in [sve2p1 or sme/sme2].
+    llvm::StringMap<bool> CallerFeatureMap;
+    S.Context.getFunctionFeatureMap(CallerFeatureMap, FD);
+    if (Builtin::evaluateRequiredTargetFeatures("sve2p1", CallerFeatureMap))
+      BuiltinType = ArmStreamingCompatible;
+    else
+      BuiltinType = ArmStreaming;
+  }
+
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sdesmalen-arm wrote:

This seems irrelevant to this patch.

https://github.com/llvm/llvm-project/pull/73672