[llvm] [VPlan] Add initial CFG simplification, removing BranchOnCond true. (PR #106748)

[Florian Hahn via llvm-commits]

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@@ -50,12 +50,6 @@ define void @test_widen(ptr noalias %a, ptr readnone %b) #4 {
 ;
 ; TFCOMMON-LABEL: @test_widen(
 ; TFCOMMON-NEXT:  entry:
-; TFCOMMON-NEXT:    [[TMP0:%.*]] = call i64 @llvm.vscale.i64()
-; TFCOMMON-NEXT:    [[TMP1:%.*]] = mul i64 [[TMP0]], 2
-; TFCOMMON-NEXT:    [[TMP2:%.*]] = sub i64 [[TMP1]], 1
-; TFCOMMON-NEXT:    [[N_RND_UP:%.*]] = add i64 1025, [[TMP2]]
-; TFCOMMON-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N_RND_UP]], [[TMP1]]
-; TFCOMMON-NEXT:    [[N_VEC:%.*]] = sub i64 [[N_RND_UP]], [[N_MOD_VF]]
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fhahn wrote:

This is due to removing the only use of N_VEC which was in the resume phi. 

As the test runs `simplifycfg` the removal of the edge and incoming value is hidden from the test changes.

https://github.com/llvm/llvm-project/pull/106748