[NFC][StructurizeCFG] Add a test that can crash StructurizeCFG pass

[shiltian]

I tried to fix it in #124051 but failed to do so. This PR adds the test and
marks it as xfail.

[shiltian]

• [NFC][StructurizeCFG] Add a test that can crash StructurizeCFG pass #126087 👈 (View in Graphite)
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[llvmbot]

@llvm/pr-subscribers-llvm-transforms

Author: Shilei Tian (shiltian)

Changes

I tried to fix it in #124051 but failed to do so. This PR adds the test and
marks it as xfail.

---

Full diff: https://github.com/llvm/llvm-project/pull/126087.diff

1 Files Affected:

• (added) llvm/test/Transforms/StructurizeCFG/simple-structurizecfg-crash.ll (+18)

diff --git a/llvm/test/Transforms/StructurizeCFG/simple-structurizecfg-crash.ll b/llvm/test/Transforms/StructurizeCFG/simple-structurizecfg-crash.ll
new file mode 100644
index 000000000000000..745b0bdc0382ada
--- /dev/null
+++ b/llvm/test/Transforms/StructurizeCFG/simple-structurizecfg-crash.ll
@@ -0,0 +1,18 @@
+; RUN: opt -S -passes=structurizecfg %s -o -
+; XFAIL: *
+
+; FIXME: This test is expected to crash. Generate checklines after the crash is fixed.
+
+define void @foo() {
+entry:
+  br i1 false, label %cond.true, label %cond.false
+
+cond.true:                                        ; preds = %entry
+  br label %cond.end
+
+cond.false:                                       ; preds = %entry
+  br label %cond.end
+
+cond.end:                                         ; preds = %cond.false, %cond.true
+  ret void
+}

[arsenm]

Can you also open a tracking issue and add a reference to the test (like in the file name)

[shiltian]

Can you also open a tracking issue and add a reference to the test (like in the file name)

Done.

[Prabhuk]

This test fails in our (Fuchsia) toolchain CI linux host builders. I am currently investigating this.

XPASS: LLVM :: Transforms/StructurizeCFG/simple-structurizecfg-crash.ll (50157 of 58077)
******************** TEST 'LLVM :: Transforms/StructurizeCFG/simple-structurizecfg-crash.ll' FAILED ********************
Exit Code: 0

Command Output (stdout):
--
; ModuleID = '/b/s/w/ir/x/w/llvm-llvm-project/llvm/test/Transforms/StructurizeCFG/simple-structurizecfg-crash.ll'
source_filename = "/b/s/w/ir/x/w/llvm-llvm-project/llvm/test/Transforms/StructurizeCFG/simple-structurizecfg-crash.ll"

define void @foo() {
entry:
  br label %cond.false

cond.true:                                        ; preds = %cond.false
  br label %cond.end

cond.false:                                       ; preds = %entry
  br i1 true, label %cond.true, label %cond.end

cond.end:                                         ; preds = %cond.true, %cond.false
  ret void
}

--
Command Output (stderr):
--
RUN: at line 1: /b/s/w/ir/x/w/llvm_build/bin/opt -S -passes=structurizecfg /b/s/w/ir/x/w/llvm-llvm-project/llvm/test/Transforms/StructurizeCFG/simple-structurizecfg-crash.ll -o -
+ /b/s/w/ir/x/w/llvm_build/bin/opt -S -passes=structurizecfg /b/s/w/ir/x/w/llvm-llvm-project/llvm/test/Transforms/StructurizeCFG/simple-structurizecfg-crash.ll -o -

Link to the logs: https://logs.chromium.org/logs/fuchsia/buildbucket/cr-buildbucket/8723305309974990577/+/u/clang/tests/stdout
Link to the bot: https://luci-milo.appspot.com/ui/p/fuchsia/builders/toolchain.ci/clang-host-linux-x64/b8723305798791238737/overview

[dyung]

I'm also seeing the test XPASS on my bot which builds without assertions enabled:

https://lab.llvm.org/staging/#/builders/202/builds/1029

[arsenm]

Requires asserts

[shiltian]

@dyung 15412d9 should hopefully fix this.