[llvm] [AMDGPU][CodeGenPrepare] Narrow 64 bit math to 32 bit if profitable (PR #130577)

[Nikita Popov via llvm-commits]

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@@ -65,8 +65,12 @@ define <4 x i16> @and_mulhuw_v4i16(<4 x i64> %a, <4 x i64> %b) {
 ;
 ; AVX512-LABEL: and_mulhuw_v4i16:
 ; AVX512:       # %bb.0:
-; AVX512-NEXT:    vpmulhuw %ymm1, %ymm0, %ymm0
-; AVX512-NEXT:    vpmovqw %zmm0, %xmm0
+; AVX512-NEXT:    # kill: def $ymm1 killed $ymm1 def $zmm1
+; AVX512-NEXT:    # kill: def $ymm0 killed $ymm0 def $zmm0
+; AVX512-NEXT:    vpmovqd %zmm0, %ymm0
+; AVX512-NEXT:    vpmovqd %zmm1, %ymm1
+; AVX512-NEXT:    vpmulhuw %xmm1, %xmm0, %xmm0
+; AVX512-NEXT:    vpshufb {{.*#+}} xmm0 = xmm0[0,1,4,5,8,9,12,13,8,9,12,13,12,13,14,15]
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nikic wrote:

Regression?

https://github.com/llvm/llvm-project/pull/130577