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

[David Sherwood via llvm-commits]

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@@ -229,50 +211,44 @@ define void @test_if_then(ptr noalias %a, ptr readnone %b) #4 {
 ; TFA_INTERLEAVE-NEXT:  [[ENTRY:.*]]:
 ; TFA_INTERLEAVE-NEXT:    [[TMP0:%.*]] = call i64 @llvm.vscale.i64()
 ; TFA_INTERLEAVE-NEXT:    [[TMP1:%.*]] = mul i64 [[TMP0]], 4
-; TFA_INTERLEAVE-NEXT:    [[TMP2:%.*]] = sub i64 [[TMP1]], 1
-; TFA_INTERLEAVE-NEXT:    [[N_RND_UP:%.*]] = add i64 1025, [[TMP2]]
-; TFA_INTERLEAVE-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N_RND_UP]], [[TMP1]]
-; TFA_INTERLEAVE-NEXT:    [[N_VEC:%.*]] = sub i64 [[N_RND_UP]], [[N_MOD_VF]]
-; TFA_INTERLEAVE-NEXT:    [[TMP3:%.*]] = call i64 @llvm.vscale.i64()
-; TFA_INTERLEAVE-NEXT:    [[TMP4:%.*]] = mul i64 [[TMP3]], 4
-; TFA_INTERLEAVE-NEXT:    [[TMP5:%.*]] = call i64 @llvm.vscale.i64()
-; TFA_INTERLEAVE-NEXT:    [[TMP6:%.*]] = mul i64 [[TMP5]], 2
+; TFA_INTERLEAVE-NEXT:    [[TMP2:%.*]] = call i64 @llvm.vscale.i64()
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david-arm wrote:

Again, not your fault but it's downright confusing!

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