[llvm] Cleanup x86_mmx after removing IR type (PR #100646)

[Phoebe Wang via llvm-commits]

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@@ -14,13 +14,13 @@ define void @foo(<1 x i64> %A, <1 x i64> %B) nounwind {
 ; CHECK-NEXT:    emms
 ; CHECK-NEXT:    retq
 entry:
-	%tmp4 = bitcast <1 x i64> %B to x86_mmx		; <<4 x i16>> [#uses=1]
-	%tmp6 = bitcast <1 x i64> %A to x86_mmx		; <<4 x i16>> [#uses=1]
-	%tmp7 = tail call x86_mmx @llvm.x86.mmx.paddus.w( x86_mmx %tmp6, x86_mmx %tmp4 )		; <x86_mmx> [#uses=1]
-	store x86_mmx %tmp7, ptr @R
+	%tmp4 = bitcast <1 x i64> %B to <1 x i64>		; <<4 x i16>> [#uses=1]
+	%tmp6 = bitcast <1 x i64> %A to <1 x i64>		; <<4 x i16>> [#uses=1]
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phoebewang wrote:

My concern is the future developer may be confused by the code and think it's intended for some purpose. It should be fine just clean up the specific `<1 x i64>` to `<1 x i64>` bitcast, which don't look many too me.

https://github.com/llvm/llvm-project/pull/100646