[llvm] [SDag] Notify listeners when deleting a node (PR #66991)

[Simon Pilgrim via llvm-commits]

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@@ -5099,8 +5099,8 @@ define <16 x i16> @shuffle_v16i16_03_07_01_00_02_07_03_13_11_15_09_08_10_15_11_1
 ;
 ; AVX2-SLOW-LABEL: shuffle_v16i16_03_07_01_00_02_07_03_13_11_15_09_08_10_15_11_13:
 ; AVX2-SLOW:       # %bb.0:
-; AVX2-SLOW-NEXT:    vmovdqa {{.*#+}} ymm1 = [0,1,6,3,4,5,6,7]
-; AVX2-SLOW-NEXT:    vpermd %ymm0, %ymm1, %ymm0
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RKSimon wrote:

This is good - its precisely what we'd expect on AVX2-SLOW/AVX2-FAST-PERLANE targets - as long as AVX2-FAST still merges to VPERMD

https://github.com/llvm/llvm-project/pull/66991