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

[Simon Pilgrim via llvm-commits]

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@@ -6519,7 +6519,7 @@ define <16 x i16> @shuffle_v16i16_03_04_05_06_07_16_17_26_11_12_13_14_15_24_25_2
 ; AVX2-LABEL: shuffle_v16i16_03_04_05_06_07_16_17_26_11_12_13_14_15_24_25_26:
 ; AVX2:       # %bb.0:
 ; AVX2-NEXT:    vpblendw {{.*#+}} ymm0 = ymm1[0,1,2],ymm0[3,4,5,6,7],ymm1[8,9,10],ymm0[11,12,13,14,15]
-; AVX2-NEXT:    vpermq {{.*#+}} ymm1 = ymm1[2,3,2,3]
+; AVX2-NEXT:    vpermq {{.*#+}} ymm1 = ymm0[2,3,2,3]
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RKSimon wrote:

regression - this is now dependent on the VPBLENDW

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