[NFC] Add test that demonstrates buggy behavior on term folding of LoopSimplifyCFG

llvm-svn: 347488

diff --git a/llvm/test/Transforms/LoopSimplifyCFG/phi_with_duplicating_inputs.ll b/llvm/test/Transforms/LoopSimplifyCFG/phi_with_duplicating_inputs.ll
new file mode 100644 (file)
index 0000000..6158fcd
--- /dev/null
+++ b/llvm/test/Transforms/LoopSimplifyCFG/phi_with_duplicating_inputs.ll
@@ -0,0 +1,29 @@
+; This is currently failing because of bug in LoopSimplifyCFG. It does not update
+; duplicating Phi inputs properly.
+; XFAIL: *
+; RUN: opt -S -enable-loop-simplifycfg-term-folding=true -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(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 -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
+
+target datalayout = "P40"
+
+@a = external global i16, align 1
+
+; CHECK-LABEL: @f1(
+
+define void @f1(i1 %cond) {
+entry:
+  br label %for.cond
+
+for.cond:
+  br i1 %cond, label %if.then, label %for.inc
+
+if.then:
+  %0 = load i16, i16* @a, align 1
+  %tobool = icmp ne i16 %0, 0
+  br i1 %tobool, label %for.inc, label %for.inc
+
+for.inc:
+  %c.1 = phi i16 [ 2, %if.then ], [ 2, %if.then ], [ 1, %for.cond ]
+  br label %for.cond
+}