[llvm] [VPlan] Run removeDeadRecipes early. (PR #190191)

[Florian Hahn via llvm-commits]

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@@ -357,12 +357,11 @@ define void @gather_interleave_group_with_dead_insert_pos(i64 %N, ptr noalias %s
 ; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <vscale x 4 x i64> poison, i64 [[TMP7]], i64 0
 ; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <vscale x 4 x i64> [[BROADCAST_SPLATINSERT]], <vscale x 4 x i64> poison, <vscale x 4 x i32> zeroinitializer
 ; CHECK-NEXT:    [[OFFSET_IDX:%.*]] = shl i64 [[EVL_BASED_IV]], 1
-; CHECK-NEXT:    [[TMP22:%.*]] = getelementptr i8, ptr [[SRC]], i64 [[OFFSET_IDX]]
-; CHECK-NEXT:    [[INTERLEAVE_EVL:%.*]] = mul nuw nsw i32 [[TMP10]], 2
-; CHECK-NEXT:    [[WIDE_MASKED_VEC:%.*]] = call <vscale x 8 x i8> @llvm.vp.load.nxv8i8.p0(ptr align 1 [[TMP22]], <vscale x 8 x i1> splat (i1 true), i32 [[INTERLEAVE_EVL]])
-; CHECK-NEXT:    [[STRIDED_VEC:%.*]] = call { <vscale x 4 x i8>, <vscale x 4 x i8> } @llvm.vector.deinterleave2.nxv8i8(<vscale x 8 x i8> [[WIDE_MASKED_VEC]])
-; CHECK-NEXT:    [[TMP23:%.*]] = extractvalue { <vscale x 4 x i8>, <vscale x 4 x i8> } [[STRIDED_VEC]], 0
-; CHECK-NEXT:    [[TMP17:%.*]] = extractvalue { <vscale x 4 x i8>, <vscale x 4 x i8> } [[STRIDED_VEC]], 1
+; CHECK-NEXT:    [[TMP11:%.*]] = add i64 [[OFFSET_IDX]], 1
+; CHECK-NEXT:    [[TMP22:%.*]] = getelementptr i8, ptr [[SRC]], i64 [[TMP11]]
+; CHECK-NEXT:    [[BROADCAST_SPLATINSERT1:%.*]] = insertelement <vscale x 4 x ptr> poison, ptr [[TMP22]], i64 0
+; CHECK-NEXT:    [[BROADCAST_SPLAT2:%.*]] = shufflevector <vscale x 4 x ptr> [[BROADCAST_SPLATINSERT1]], <vscale x 4 x ptr> poison, <vscale x 4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP17:%.*]] = call <vscale x 4 x i8> @llvm.vp.gather.nxv4i8.nxv4p0(<vscale x 4 x ptr> align 1 [[BROADCAST_SPLAT2]], <vscale x 4 x i1> splat (i1 true), i32 [[TMP10]])
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fhahn wrote:

This is due to the loop having a dead load; it is now removed, and we won't form an interleave group. In. the optimization pipeline, those would have been cleaned up earlier as well, so this should match the behavior there as well.

We could still try and form a load interleave-group though if desired I think

https://github.com/llvm/llvm-project/pull/190191