[clang] [llvm] [LLVMAABI][AARCH64] Handle homogeneous aggregate return types (PR #218799)

[Madhur Amilkanthwar via cfe-commits]

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@@ -67,7 +77,7 @@ ArgInfo AArch64TargetInfo::classifyReturnType(const Type *RetTy,
 
   if (RetTy->isVector()) {
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madhur13490 wrote:

Changing the unsupported-vector result from `Direct` to `Ignore` also
changes legal 64-bit and 128-bit vector returns and arguments, which
Clang classifies as `Direct`. This is not merely a more visible failure:
release builds produce a different function signature, while the debug
parity check detects a mismatch.

Could the `Ignore` change be limited to unsupported aggregates, while
legal top-level vectors remain `Direct`? The same issue occurs in the
argument path at lines `116-118`.

https://github.com/llvm/llvm-project/pull/218799