|  | ; RUN: opt -instcombine -S < %s | FileCheck %s | 
|  |  | 
|  | ; This used to crash opt | 
|  |  | 
|  | @c = common global i32 0, align 4 | 
|  | @b = common global i32 0, align 4 | 
|  | @a = common global i16 0, align 2 | 
|  | @d = common global i32 0, align 4 | 
|  |  | 
|  | define void @fn3() { | 
|  | ; CHECK: @fn3 | 
|  | bb: | 
|  | %tmp = load i32, i32* @c, align 4 | 
|  | %tmp1 = icmp eq i32 %tmp, 0 | 
|  | br i1 %tmp1, label %bb2, label %bb6 | 
|  |  | 
|  | bb2:                                              ; preds = %bb | 
|  | %tmp3 = load i32, i32* @b, align 4 | 
|  | %tmp.i = add nsw i32 255, %tmp3 | 
|  | %tmp5 = icmp ugt i32 %tmp.i, 254 | 
|  | br label %bb6 | 
|  |  | 
|  | bb6:                                              ; preds = %bb, %bb2 | 
|  | %tmp7 = phi i1 [ true, %bb ], [ %tmp5, %bb2 ] | 
|  | %tmp8 = zext i1 %tmp7 to i32 | 
|  | %tmp10 = icmp eq i32 %tmp8, 0 | 
|  | %tmp12 = load i16, i16* @a, align 2 | 
|  | %tmp14 = icmp ne i16 %tmp12, 0 | 
|  | %tmp16 = select i1 %tmp10, i1 false, i1 %tmp14 | 
|  | %tmp17 = zext i1 %tmp16 to i32 | 
|  | store i32 %tmp17, i32* @d, align 4 | 
|  | ret void | 
|  | } |