[clang] [llvm] [mlir] Remove the `x86_mmx` IR type. (PR #98505)

[James Y Knight via cfe-commits]

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@@ -44,8 +44,8 @@ Type *Type::getPrimitiveType(LLVMContext &C, TypeID IDNumber) {
   case FP128TyID     : return getFP128Ty(C);
   case PPC_FP128TyID : return getPPC_FP128Ty(C);
   case LabelTyID     : return getLabelTy(C);
-  case MetadataTyID  : return getMetadataTy(C);
-  case X86_MMXTyID   : return getX86_MMXTy(C);
+  case MetadataTyID:
+    return getMetadataTy(C);
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jyknight wrote:

That's just what clang-format chose to do. If I modify it back and run clang-format again, it puts it back like this, again.

It'd be great if the whole codebase got clang-formatted so changes to neighboring code like this didn't happen (because all of the case clauses would already be formatted like this), but in the meantime, I think it's better to just go with what the formatter says, unless it causes a lot of noise or is egregiously wrong.

https://github.com/llvm/llvm-project/pull/98505