[PATCH] D140831: Fix a phase-ordering problem in SimplifyCFG.

[Nikita Popov via Phabricator via llvm-commits]

nikic added a reviewer: nikic.
nikic added inline comments.


================
Comment at: llvm/test/Transforms/SimplifyCFG/switch-simplify-crash2.ll:2
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -S -O2 < %s | FileCheck %s
+
----------------
Outside PhaseOrdering, tests should not use the full optimization pipeline. Here is a reduction of your test case:

```
; RUN: opt -S -passes="simplifycfg<forward-switch-cond;no-keep-loops>" < %s | FileCheck %s

define i8 @test() {
entry:
  br label %loop

loop:
  %phi1 = phi i8 [ 0, %entry ], [ %phi2, %loop2 ]
  br label %loop2

loop2:
  %phi2 = phi i8 [ %phi1, %loop ], [ 0, %loop2 ]
  switch i8 %phi2, label %loop [
    i8 0, label %loop2
    i8 1, label %exit
  ]

exit:
  ret i8 0
}
```

Please also reference the issue.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D140831/new/

https://reviews.llvm.org/D140831