[llvm] [VPlan] Simplify Plan's entry in removeBranchOnConst. (PR #154510)

[via llvm-commits]

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@@ -67,53 +67,17 @@ define void @f(ptr noundef captures(none) %a, float noundef %x) {
 ; CHECK-NEXT:    br i1 [[TMP4]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
 ; CHECK:       [[MIDDLE_BLOCK]]:
 ; CHECK-NEXT:    br label %[[EXIT:.*]]
-; CHECK:       [[SCALAR_PH]]:
+; CHECK:       [[SCALAR_PH:.*]]:
 ; CHECK-NEXT:    br label %[[FOR_BODY:.*]]
 ; CHECK:       [[FOR_BODY]]:
-; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[SCALAR_PH]] ], [ [[IV_NEXT_7:%.*]], %[[FOR_BODY]] ]
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[FOR_BODY]] ]
 ; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds nuw float, ptr [[A]], i64 [[IV]]
 ; CHECK-NEXT:    [[LOAD:%.*]] = load float, ptr [[ARRAYIDX]], align 4
 ; CHECK-NEXT:    [[MUL:%.*]] = fmul float [[X]], [[LOAD]]
 ; CHECK-NEXT:    store float [[MUL]], ptr [[ARRAYIDX]], align 4
-; CHECK-NEXT:    [[IV_NEXT:%.*]] = add nuw nsw i64 [[IV]], 1
-; CHECK-NEXT:    [[ARRAYIDX_1:%.*]] = getelementptr inbounds nuw float, ptr [[A]], i64 [[IV_NEXT]]
-; CHECK-NEXT:    [[LOAD_1:%.*]] = load float, ptr [[ARRAYIDX_1]], align 4
-; CHECK-NEXT:    [[MUL_1:%.*]] = fmul float [[X]], [[LOAD_1]]
-; CHECK-NEXT:    store float [[MUL_1]], ptr [[ARRAYIDX_1]], align 4
-; CHECK-NEXT:    [[IV_NEXT_1:%.*]] = add nuw nsw i64 [[IV]], 2
-; CHECK-NEXT:    [[ARRAYIDX_2:%.*]] = getelementptr inbounds nuw float, ptr [[A]], i64 [[IV_NEXT_1]]
-; CHECK-NEXT:    [[LOAD_2:%.*]] = load float, ptr [[ARRAYIDX_2]], align 4
-; CHECK-NEXT:    [[MUL_2:%.*]] = fmul float [[X]], [[LOAD_2]]
-; CHECK-NEXT:    store float [[MUL_2]], ptr [[ARRAYIDX_2]], align 4
-; CHECK-NEXT:    [[IV_NEXT_2:%.*]] = add nuw nsw i64 [[IV]], 3
-; CHECK-NEXT:    [[ARRAYIDX_3:%.*]] = getelementptr inbounds nuw float, ptr [[A]], i64 [[IV_NEXT_2]]
-; CHECK-NEXT:    [[LOAD_3:%.*]] = load float, ptr [[ARRAYIDX_3]], align 4
-; CHECK-NEXT:    [[MUL_3:%.*]] = fmul float [[X]], [[LOAD_3]]
-; CHECK-NEXT:    store float [[MUL_3]], ptr [[ARRAYIDX_3]], align 4
-; CHECK-NEXT:    [[IV_NEXT_3:%.*]] = add nuw nsw i64 [[IV]], 4
-; CHECK-NEXT:    [[ARRAYIDX_4:%.*]] = getelementptr inbounds nuw float, ptr [[A]], i64 [[IV_NEXT_3]]
-; CHECK-NEXT:    [[LOAD_4:%.*]] = load float, ptr [[ARRAYIDX_4]], align 4
-; CHECK-NEXT:    [[MUL_4:%.*]] = fmul float [[X]], [[LOAD_4]]
-; CHECK-NEXT:    store float [[MUL_4]], ptr [[ARRAYIDX_4]], align 4
-; CHECK-NEXT:    [[IV_NEXT_4:%.*]] = add nuw nsw i64 [[IV]], 5
-; CHECK-NEXT:    [[ARRAYIDX_5:%.*]] = getelementptr inbounds nuw float, ptr [[A]], i64 [[IV_NEXT_4]]
-; CHECK-NEXT:    [[LOAD_5:%.*]] = load float, ptr [[ARRAYIDX_5]], align 4
-; CHECK-NEXT:    [[MUL_5:%.*]] = fmul float [[X]], [[LOAD_5]]
-; CHECK-NEXT:    store float [[MUL_5]], ptr [[ARRAYIDX_5]], align 4
-; CHECK-NEXT:    [[IV_NEXT_5:%.*]] = add nuw nsw i64 [[IV]], 6
-; CHECK-NEXT:    [[ARRAYIDX_6:%.*]] = getelementptr inbounds nuw float, ptr [[A]], i64 [[IV_NEXT_5]]
-; CHECK-NEXT:    [[LOAD_6:%.*]] = load float, ptr [[ARRAYIDX_6]], align 4
-; CHECK-NEXT:    [[MUL_6:%.*]] = fmul float [[X]], [[LOAD_6]]
-; CHECK-NEXT:    store float [[MUL_6]], ptr [[ARRAYIDX_6]], align 4
-; CHECK-NEXT:    [[IV_NEXT_6:%.*]] = add nuw nsw i64 [[IV]], 7
-; CHECK-NEXT:    [[ARRAYIDX_7:%.*]] = getelementptr inbounds nuw float, ptr [[A]], i64 [[IV_NEXT_6]]
-; CHECK-NEXT:    [[LOAD_7:%.*]] = load float, ptr [[ARRAYIDX_7]], align 4
-; CHECK-NEXT:    [[MUL_7:%.*]] = fmul float [[X]], [[LOAD_7]]
-; CHECK-NEXT:    store float [[MUL_7]], ptr [[ARRAYIDX_7]], align 4
-; CHECK-NEXT:    [[IV_NEXT_7]] = add nuw nsw i64 [[IV]], 8
-; CHECK-NEXT:    br i1 true, label %[[EXIT_LOOPEXIT:.*]], label %[[FOR_BODY]], !llvm.loop [[LOOP3:![0-9]+]]
-; CHECK:       [[EXIT_LOOPEXIT]]:
-; CHECK-NEXT:    br label %[[EXIT]]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1
+; CHECK-NEXT:    [[COMP:%.*]] = icmp eq i64 [[IV_NEXT]], 1024
+; CHECK-NEXT:    br i1 [[COMP]], label %[[EXIT]], label %[[FOR_BODY]], !llvm.loop [[LOOP3:![0-9]+]]
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ayalz wrote:

Dropped unrolling (requested, of vector loop) of unreachable scalar loop?

https://github.com/llvm/llvm-project/pull/154510