[llvm] VPlan: use worklist in simplifyRecipes (PR #93998)

[Florian Hahn via llvm-commits]

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@@ -7,135 +7,109 @@ define void @test(ptr %p, i40 %a) {
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    br i1 false, label [[SCALAR_PH:%.*]], label [[VECTOR_PH:%.*]]
 ; CHECK:       vector.ph:
-; CHECK-NEXT:    [[BROADCAST_SPLATINSERT1:%.*]] = insertelement <16 x i40> poison, i40 [[A]], i64 0
-; CHECK-NEXT:    [[BROADCAST_SPLAT2:%.*]] = shufflevector <16 x i40> [[BROADCAST_SPLATINSERT1]], <16 x i40> poison, <16 x i32> zeroinitializer
 ; CHECK-NEXT:    br label [[VECTOR_BODY:%.*]]
 ; CHECK:       vector.body:
 ; CHECK-NEXT:    [[INDEX:%.*]] = phi i32 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[PRED_STORE_CONTINUE32:%.*]] ]
 ; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <16 x i32> poison, i32 [[INDEX]], i64 0
 ; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <16 x i32> [[BROADCAST_SPLATINSERT]], <16 x i32> poison, <16 x i32> zeroinitializer
 ; CHECK-NEXT:    [[VEC_IV:%.*]] = add <16 x i32> [[BROADCAST_SPLAT]], <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>
 ; CHECK-NEXT:    [[TMP0:%.*]] = icmp ule <16 x i32> [[VEC_IV]], <i32 9, i32 9, i32 9, i32 9, i32 9, i32 9, i32 9, i32 9, i32 9, i32 9, i32 9, i32 9, i32 9, i32 9, i32 9, i32 9>
-; CHECK-NEXT:    [[TMP1:%.*]] = shl <16 x i40> [[BROADCAST_SPLAT2]], <i40 24, i40 24, i40 24, i40 24, i40 24, i40 24, i40 24, i40 24, i40 24, i40 24, i40 24, i40 24, i40 24, i40 24, i40 24, i40 24>
-; CHECK-NEXT:    [[TMP2:%.*]] = ashr <16 x i40> [[TMP1]], <i40 28, i40 28, i40 28, i40 28, i40 28, i40 28, i40 28, i40 28, i40 28, i40 28, i40 28, i40 28, i40 28, i40 28, i40 28, i40 28>
-; CHECK-NEXT:    [[TMP3:%.*]] = trunc <16 x i40> [[TMP2]] to <16 x i32>
-; CHECK-NEXT:    [[TMP4:%.*]] = trunc <16 x i32> [[TMP3]] to <16 x i1>
-; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq <16 x i1> [[TMP4]], zeroinitializer
-; CHECK-NEXT:    [[TMP6:%.*]] = icmp ult <16 x i1> zeroinitializer, [[TMP5]]
-; CHECK-NEXT:    [[TMP7:%.*]] = or <16 x i1> [[TMP6]], <i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true>
-; CHECK-NEXT:    [[TMP8:%.*]] = icmp sgt <16 x i1> [[TMP7]], zeroinitializer
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fhahn wrote:

Do you know how this gets simplified? I might be missing something but, [[TMP7]] = 1, so should't `[[TMP8]]` be all-true? But below it's replaced by `false`?

https://github.com/llvm/llvm-project/pull/93998