[TEST] Add failing test that shows problems with MSSA update in LoopSimplifyCFG
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354559 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Transforms/LoopSimplifyCFG/mssa_update.ll b/test/Transforms/LoopSimplifyCFG/mssa_update.ll
new file mode 100644
index 0000000..01f2ebb
--- /dev/null
+++ b/test/Transforms/LoopSimplifyCFG/mssa_update.ll
@@ -0,0 +1,41 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; REQUIRES: asserts
+; XFAIL: *
+; RUN: opt -S -enable-loop-simplifycfg-term-folding=true -loop-simplifycfg -verify-loop-info -verify-dom-info -verify-loop-lcssa < %s | FileCheck %s
+; RUN: opt -S -enable-loop-simplifycfg-term-folding=true -passes='require<domtree>,loop(simplify-cfg)' -verify-loop-info -verify-dom-info -verify-loop-lcssa < %s | FileCheck %s
+; RUN: opt -S -enable-loop-simplifycfg-term-folding=true -loop-simplifycfg -enable-mssa-loop-dependency=true -verify-memoryssa -verify-loop-info -verify-dom-info -verify-loop-lcssa < %s | FileCheck %s
+
+target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
+
+; Make sure we update MSSA properly.
+define void @test(i32* %a, i32* %b) {
+; CHECK-LABEL: @test(
+
+entry:
+ br label %for.body
+
+for.body:
+ %i = phi i32 [ 0, %entry ], [ %i.inc, %latch ]
+ br label %switch.bb
+
+switch.bb:
+ switch i2 1, label %default [
+ i2 1, label %case
+ ]
+
+case:
+ br label %latch
+
+default:
+ unreachable
+
+latch:
+ store i32 %i, i32* %a
+ store i32 %i, i32* %b
+ %i.inc = add nsw i32 %i, 1
+ %exitcond = icmp eq i32 %i.inc, 4
+ br i1 %exitcond, label %exit, label %for.body
+
+exit:
+ ret void
+}
