https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66917
--- Comment #11 from Richard Biener <rguenth at gcc dot gnu.org> --- Suggested fix: Index: gcc/config/arm/arm.c =================================================================== --- gcc/config/arm/arm.c (revision 226348) +++ gcc/config/arm/arm.c (working copy) @@ -27217,7 +27217,8 @@ arm_builtin_support_vector_misalignment { if (TARGET_NEON && !BYTES_BIG_ENDIAN && unaligned_access) { - HOST_WIDE_INT align = TYPE_ALIGN_UNIT (type); + HOST_WIDE_INT align + = GET_MODE_ALIGNMENT (TYPE_MODE (type)) / BITS_PER_UNIT; if (is_packed) return align == 1; which produces push {r4} add r3, r0, #8 add r4, r1, #8 vld1.64 {d17}, [r1] vld1.64 {d16}, [r4] ldr r4, [sp], #4 vld1.64 {d19}, [r3] veor d16, d16, d19 vld1.64 {d18}, [r0] veor d17, d17, d18 vst1.64 {d17}, [r2]! vst1.64 {d16}, [r2] bx lr