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

[James Y Knight via cfe-commits]

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@@ -94,14 +94,15 @@ entry:
 
 ;
 ; MMX Store
+; Note: doesn't actually emit a non-temporal store here.
 ;
 
 define void @test_mmx(ptr nocapture %a0, ptr nocapture %a1) {
 ; ALL-LABEL: test_mmx:
 ; ALL:       # %bb.0: # %entry
 ; ALL-NEXT:    movq (%rdi), %mm0
 ; ALL-NEXT:    psrlq $3, %mm0
-; ALL-NEXT:    movntq %mm0, (%rsi)
+; ALL-NEXT:    movq %mm0, (%rsi)
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jyknight wrote:

Correct; this already wasn't happening under SDag ISel. Now it _also_ isn't happening under fast ISel.

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