1 files changed, 71 insertions, 0 deletions
diff --git a/llvm/test/Transforms/LoopVectorize/pr28541.ll b/llvm/test/Transforms/LoopVectorize/pr28541.ll
new file mode 100644
index 00000000000..7bb7f0987fd
--- /dev/null
+++ b/llvm/test/Transforms/LoopVectorize/pr28541.ll
@@ -0,0 +1,71 @@
+; RUN: opt -loop-vectorize -pass-remarks=loop-vectorize -S < %s 2>&1 | FileCheck %s
+
+; FIXME: Check for -pass-remarks-missed and -pass-remarks-analysis output when
+; addAcyclicInnerLoop emits analysis.
+
+; Check that opt does not crash on such input:
+;
+; a, b, c;
+; fn1() {
+;   while (b--) {
+;     c = a;
+;     switch (a & 3)
+;     case 0:
+;       do
+;     case 3:
+;     case 2:
+;     case 1:
+;         ;
+;         while (--c)
+;           ;
+;   }
+; }
+
+@b = common global i32 0, align 4
+@a = common global i32 0, align 4
+@c = common global i32 0, align 4
+
+; CHECK-NOT: vectorized loop
+; CHECK-LABEL: fn1
+
+define i32 @fn1() {
+entry:
+  %tmp2 = load i32, i32* @b, align 4
+  %dec3 = add nsw i32 %tmp2, -1
+  store i32 %dec3, i32* @b, align 4
+  %tobool4 = icmp eq i32 %tmp2, 0
+  br i1 %tobool4, label %while.end, label %while.body.lr.ph
+
+while.body.lr.ph:                                 ; preds = %entry
+  %tmp1 = load i32, i32* @a, align 4
+  %and = and i32 %tmp1, 3
+  %switch = icmp eq i32 %and, 0
+  br label %while.body
+
+while.cond:                                       ; preds = %do.cond
+  %dec = add nsw i32 %dec7, -1
+  %tobool = icmp eq i32 %dec7, 0
+  br i1 %tobool, label %while.cond.while.end_crit_edge, label %while.body
+
+while.body:                                       ; preds = %while.body.lr.ph, %while.cond
+  %dec7 = phi i32 [ %dec3, %while.body.lr.ph ], [ %dec, %while.cond ]
+  br i1 %switch, label %do.body, label %do.cond
+
+do.body:                                          ; preds = %do.cond, %while.body
+  %dec25 = phi i32 [ %dec2, %do.cond ], [ %tmp1, %while.body ]
+  br label %do.cond
+
+do.cond:                                          ; preds = %do.body, %while.body
+  %dec26 = phi i32 [ %dec25, %do.body ], [ %tmp1, %while.body ]
+  %dec2 = add nsw i32 %dec26, -1
+  %tobool3 = icmp eq i32 %dec2, 0
+  br i1 %tobool3, label %while.cond, label %do.body
+
+while.cond.while.end_crit_edge:                   ; preds = %while.cond
+  store i32 0, i32* @c, align 4
+  store i32 -1, i32* @b, align 4
+  br label %while.end
+
+while.end:                                        ; preds = %while.cond.while.end_crit_edge, %entry
+  ret i32 undef
+}