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

[via llvm-commits]

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@@ -1,10 +1,25 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
 ; RUN: opt -S -passes=loop-vectorize,instsimplify,simplifycfg -force-vector-interleave=1 -force-vector-width=4 -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck %s
 ; Note: -passes=instsimplify,simplifycfg -simplifycfg-require-and-preserve-domtree=1 remove the (now dead) original loop, making
 ; it easy to test that the llvm.loop.unroll.disable hint is still present.
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 
 ; Function Attrs: norecurse nounwind uwtable
 define void @foo(ptr nocapture %b) #0 {
+; CHECK-LABEL: define void @foo(
+; CHECK-SAME: ptr captures(none) [[B:%.*]]) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr inbounds i32, ptr [[B]], i64 [[INDEX]]
+; CHECK-NEXT:    store <4 x i32> splat (i32 1), ptr [[TMP0]], align 4
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 4
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp eq i64 [[INDEX_NEXT]], 16
+; CHECK-NEXT:    br i1 [[TMP1]], label %[[FOR_COND_CLEANUP:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       [[FOR_COND_CLEANUP]]:
+; CHECK-NEXT:    ret void
+;
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ayalz wrote:

Change needed?

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