[clang] [clang] Limit alignment for emitted vectors (PR #98629)

[Phoebe Wang via cfe-commits]

================
@@ -133,6 +133,7 @@ struct TransferrableTargetInfo {
   unsigned short SuitableAlign;
   unsigned short NewAlign;
   unsigned MaxVectorAlign;
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phoebewang wrote:

I'm surprised the change of alignment affects ABI. Did you just expand
```
    MaxVectorAlign =
        hasFeature("avx512f") ? 512 : hasFeature("avx") ? 256 : 128;
```
to other targets in X86.h, or together with the change here?

I assumed the former won't change return type to `set`, though align may need to update.

https://github.com/llvm/llvm-project/pull/98629