[llvm] [VPlan] Expand VPWidenPointerInductionRecipe into separate recipes (PR #148274)

[Florian Hahn via llvm-commits]

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@@ -125,15 +119,9 @@ define void @pointer_induction(ptr noalias %start, i64 %N) {
 ; CHECK:       vector.body:
 ; CHECK-NEXT:    [[INDEX2:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[POINTER_PHI:%.*]] = phi ptr [ [[START]], [[VECTOR_PH]] ], [ [[PTR_IND:%.*]], [[VECTOR_BODY]] ]
-; CHECK-NEXT:    [[TMP7:%.*]] = call i64 @llvm.vscale.i64()
-; CHECK-NEXT:    [[TMP8:%.*]] = mul nuw i64 [[TMP7]], 2
 ; CHECK-NEXT:    [[TMP10:%.*]] = mul i64 1, [[TMP6]]
-; CHECK-NEXT:    [[TMP11:%.*]] = mul i64 [[TMP8]], 0
-; CHECK-NEXT:    [[DOTSPLATINSERT:%.*]] = insertelement <vscale x 2 x i64> poison, i64 [[TMP11]], i64 0
-; CHECK-NEXT:    [[DOTSPLAT:%.*]] = shufflevector <vscale x 2 x i64> [[DOTSPLATINSERT]], <vscale x 2 x i64> poison, <vscale x 2 x i32> zeroinitializer
 ; CHECK-NEXT:    [[TMP12:%.*]] = call <vscale x 2 x i64> @llvm.stepvector.nxv2i64()
-; CHECK-NEXT:    [[TMP13:%.*]] = add <vscale x 2 x i64> [[DOTSPLAT]], [[TMP12]]
-; CHECK-NEXT:    [[TMP14:%.*]] = mul <vscale x 2 x i64> [[TMP13]], splat (i64 1)
+; CHECK-NEXT:    [[TMP14:%.*]] = mul <vscale x 2 x i64> [[TMP12]], splat (i64 1)
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fhahn wrote:

just noting that this is fine, as `DOTSPLAT` in the old IR was 0.

https://github.com/llvm/llvm-project/pull/148274