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

[Madhur Amilkanthwar via cfe-commits]

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@@ -77,8 +77,17 @@ llvm::Type *IRTypeMapper::convertArrayType(const abi::ArrayType *AT) {
 }
 
 llvm::Type *IRTypeMapper::convertVectorType(const abi::VectorType *VT) {
+  if (VT->isSVECount())
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madhur13490 wrote:

Heads up that these new branches (svcount → target ext type, tuple → struct) aren't exercised yet: the reverse mapper only runs when the library returns a non-null coerce-to type, and right now every SVE type comes back as getDirect() with a null coerce. Good to add a direct unit test so they don't rot before something relies on them.

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