--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/other/pr55073.C	Thu Oct 25 07:37:49 2018 +0900
@@ -0,0 +1,74 @@
+/* { dg-do run { target arm*-*-* } } */
+/* { dg-require-effective-target arm_neon } */
+/* { dg-options "-O2" } */
+/* { dg-add-options arm_neon } */
+
+#include <arm_neon.h>
+#include <stdlib.h>
+
+struct __attribute__((aligned(16))) _v16u8_ {
+	uint8x16_t val;
+	_v16u8_() { }
+
+	_v16u8_( const  uint8x16_t &src) { val = src; }
+	_v16u8_( const   int16x8_t &src) { val = vreinterpretq_u8_s16(src); }
+	_v16u8_( const  uint32x4_t &src) { val = vreinterpretq_u8_u32(src); }
+
+	operator  uint8x16_t () const { return val; }
+	operator   int8x16_t () const { return vreinterpretq_s8_u8 (val); }
+	operator   int16x8_t () const { return vreinterpretq_s16_u8(val); }
+	operator  uint32x4_t () const { return vreinterpretq_u32_u8(val); }
+	operator   int32x4_t () const { return vreinterpretq_s32_u8(val); }
+};
+typedef struct _v16u8_ v16u8;
+typedef const v16u8 cv16u8;
+
+typedef v16u8 v16i8;
+typedef v16u8 v8i16;
+typedef v16u8 v4u32;
+
+inline v16u8 __attribute__((always_inline)) mergelo( const v16u8 & s, const v16u8 & t )
+{
+	uint8x8x2_t r = vzip_u8( vget_low_u8(s), vget_low_u8(t) );
+	return vcombine_u8( r.val[0], r.val[1] );
+}
+
+inline v8i16 __attribute__((always_inline)) unpacklo(const v16i8 & s)
+{
+	return vmovl_s8( vget_low_s8( s ) );
+}
+
+const uint32_t __attribute__((aligned(16))) _InA [4] = { 0xFF020001, 0xFF020001, 0xFF000101, 0xFF000101 } ;
+const uint32_t __attribute__((aligned(16))) _InB [4] = { 0xFF050002, 0xFF050002, 0xFF000303, 0xFF000203 } ;
+
+__attribute__((noinline)) v16i8 test_func(void)
+{
+	v16u8 A = vld1q_u8( (uint8_t*) _InA );
+	v16u8 B = vld1q_u8( (uint8_t*) _InB );
+	v8i16 r   = vdupq_n_s16(2);
+
+	v16u8 _0 = mergelo( A, B );
+	v16u8 _1 = mergelo( B, A );
+
+	v16u8 _2 = mergelo( _0, _1 );
+	v16u8 _3 = mergelo( _1, _0 );
+
+	v8i16 _4 = vsubq_s16( unpacklo( _2 ), r );
+	v8i16 _5 = vsubq_s16( unpacklo( _3 ), r );
+
+	v8i16 ret = vaddq_s16( _4, _5 );
+
+	return ( ret );
+}
+
+int main (int argc, char **argv)
+{
+	v16u8 val = test_func();
+
+	if (vgetq_lane_u32( val, 0 ) != 0xffffffff
+	    || vgetq_lane_u32( val, 1 ) != 0xffffffff
+	    || vgetq_lane_u32( val, 2 ) != 0xfffcfffc
+	    || vgetq_lane_u32( val, 3 ) != 0xfffcfffc)
+	  abort ();
+	exit (0);
+}