From 11d3314241e056748da065b865ad9bf2496cbf76 Mon Sep 17 00:00:00 2001
From: Max Kazantsev <max.kazantsev@azul.com>
Date: Thu, 24 Jan 2019 05:05:55 +0000
Subject: [PATCH] [NFC] Add a failing test on live block markup in term folding

llvm-svn: 352023
---
 .../LoopSimplifyCFG/live_block_marking.ll     | 40 +++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 llvm/test/Transforms/LoopSimplifyCFG/live_block_marking.ll

diff --git a/llvm/test/Transforms/LoopSimplifyCFG/live_block_marking.ll b/llvm/test/Transforms/LoopSimplifyCFG/live_block_marking.ll
new file mode 100644
index 000000000000..a4c0bac41214
--- /dev/null
+++ b/llvm/test/Transforms/LoopSimplifyCFG/live_block_marking.ll
@@ -0,0 +1,40 @@
+; XFAIL: *
+; REQUIRES: asserts
+; RUN: opt -S -enable-loop-simplifycfg-term-folding=true -indvars -loop-simplifycfg -debug-only=loop-simplifycfg -verify-loop-info -verify-dom-info -verify-loop-lcssa 2>&1 < %s | FileCheck %s
+; RUN: opt -S -enable-loop-simplifycfg-term-folding=true -passes='require<domtree>,loop(indvars,simplify-cfg)' -debug-only=loop-simplifycfg -verify-loop-info -verify-dom-info -verify-loop-lcssa 2>&1 < %s | FileCheck %s
+; RUN: opt -S -enable-loop-simplifycfg-term-folding=true -indvars -loop-simplifycfg -enable-mssa-loop-dependency=true -verify-memoryssa -debug-only=loop-simplifycfg -verify-loop-info -verify-dom-info -verify-loop-lcssa 2>&1 < %s | FileCheck %s
+
+; This test demonstrates a bug in live blocks markup that is only catchable in
+; inter-pass interaction.
+define void @test(i1 %c) {
+
+; CHECK-LABEL: @test(
+
+entry:
+  br label %outer
+
+outer:
+  br i1 %c, label %to_fold, label %latch
+
+to_fold:
+  br i1 %c, label %latch, label %inner
+
+inner:
+  %iv = phi i32 [0, %to_fold], [%iv.next, %inner_latch]
+  %never = icmp sgt i32 %iv, 40
+  br i1 %never, label %inner_latch, label %undead
+
+inner_latch:
+  %iv.next = add i32 %iv, 1
+  %cmp = icmp slt i32 %iv.next, 10
+  br i1 %cmp, label %inner, label %latch
+
+undead:
+  br label %latch
+
+latch:
+  br i1 true, label %outer, label %dead_exit
+
+dead_exit:
+  ret void
+}