1 files changed, 45 insertions, 0 deletions
diff --git a/test/Transforms/IRCE/bad-loop-structure.ll b/test/Transforms/IRCE/bad-loop-structure.ll
new file mode 100644
index 000000000000..9c2e4251423d
--- /dev/null
+++ b/test/Transforms/IRCE/bad-loop-structure.ll
@@ -0,0 +1,45 @@
+; RUN: opt -S -irce -irce-print-changed-loops=true < %s | FileCheck %s
+
+; CHECK-NOT: irce
+
+define void @bad_loop_structure_increasing(i64 %iv.start) {
+entry:
+  br label %for.body
+
+for.body:
+  %indvars.iv = phi i64 [ %iv.start, %entry ], [ %indvars.iv.next, %for.inc ]
+  %cmp = icmp ult i64 %indvars.iv, 100
+  br i1 %cmp, label %switch.lookup, label %for.inc
+
+switch.lookup:
+  br label %for.inc
+
+for.inc:
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %cmp55 = icmp slt i64 %indvars.iv.next, 11
+  br i1 %cmp55, label %for.body, label %for.end
+
+for.end:
+  ret void
+}
+
+define void @bad_loop_structure_decreasing(i64 %iv.start) {
+entry:
+  br label %for.body
+
+for.body:
+  %indvars.iv = phi i64 [ %iv.start, %entry ], [ %indvars.iv.next, %for.inc ]
+  %cmp = icmp ult i64 %indvars.iv, 100
+  br i1 %cmp, label %switch.lookup, label %for.inc
+
+switch.lookup:
+  br label %for.inc
+
+for.inc:
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, -1
+  %cmp55 = icmp sgt i64 %indvars.iv.next, 11
+  br i1 %cmp55, label %for.body, label %for.end
+
+for.end:
+  ret void
+}