[clang] [llvm] [LLVMABI] Add support for SVE types in the LLVM ABI library (PR #221375)

[Madhur Amilkanthwar via cfe-commits]

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@@ -242,11 +267,27 @@ QualTypeMapper::convertBuiltinType(const BuiltinType *BT) {
   case BuiltinType::ObjCSel:
     return createPointerTypeForPointee(QT);
 
-    // Target-specific vector/matrix types — not yet implemented.
-#define SVE_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
+    // AArch64 SVE data and predicate types, including the x2/x3/x4 tuples.
+#define SVE_VECTOR_TYPE(Name, MangledName, Id, SingletonId)                    \
+  case BuiltinType::Id:
+#define SVE_PREDICATE_TYPE(Name, MangledName, Id, SingletonId)                 \
+  case BuiltinType::Id:
 #include "clang/Basic/AArch64ACLETypes.def"
+    return convertSVEBuiltinType(BT);
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madhur13490 wrote:

This is where my main concern enters, not with the mapping but with what it enables. Before this, any SVE type hard-errored right here, so computeABIInfoUsingLib never got further. Now the type maps cleanly and flows into the AArch64 target's vector path, which is still reportNYI + getDirect() — and since that's only a warning, the wrong classification is used. For SVE tuples under register exhaustion that means we return Direct where AAPCS64 C.8 / the classic path return Indirect, and the debug oracle in CGCall.cpp aborts (repro in the top-level comment). Can we gate SVE out of shouldUseLLVMABILowering, or implement the indirect path, before enabling the mapping

https://github.com/llvm/llvm-project/pull/221375