https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109780
--- Comment #34 from Uroš Bizjak <ubizjak at gmail dot com> ---
The problematic code is expanded from:
;; Generating RTL for gimple basic block 5
;; __builtin_memset (&k, 0, 40);
(insn 21 20 22 (parallel [
(set (reg:DI 107)
(plus:DI (reg/f:DI 93 virtual-stack-vars)
(const_int -48 [0xffffffffffffffd0])))
(clobber (reg:CC 17 flags))
]) "pr109780.c":11:12 -1
(nil))
(insn 22 21 23 (set (reg:V32QI 108)
(const_vector:V32QI [
(const_int 0 [0]) repeated x32
])) "pr109780.c":11:12 -1
(nil))
(insn 23 22 24 (set (mem/c:V16QI (reg:DI 107) [0 MEM <char[1:40]> [(void
*)&k]+0 S16 A128])
(vec_select:V16QI (reg:V32QI 108)
(parallel [
(const_int 0 [0])
(const_int 1 [0x1])
(const_int 2 [0x2])
(const_int 3 [0x3])
(const_int 4 [0x4])
(const_int 5 [0x5])
(const_int 6 [0x6])
(const_int 7 [0x7])
(const_int 8 [0x8])
(const_int 9 [0x9])
(const_int 10 [0xa])
(const_int 11 [0xb])
(const_int 12 [0xc])
(const_int 13 [0xd])
(const_int 14 [0xe])
(const_int 15 [0xf])
]))) "pr109780.c":11:12 -1
(nil))
(insn 24 23 25 (set (mem/c:V16QI (plus:DI (reg:DI 107)
(const_int 16 [0x10])) [0 MEM <char[1:40]> [(void *)&k]+16 S16
A128])
(vec_select:V16QI (reg:V32QI 108)
(parallel [
(const_int 16 [0x10])
(const_int 17 [0x11])
(const_int 18 [0x12])
(const_int 19 [0x13])
(const_int 20 [0x14])
(const_int 21 [0x15])
(const_int 22 [0x16])
(const_int 23 [0x17])
(const_int 24 [0x18])
(const_int 25 [0x19])
(const_int 26 [0x1a])
(const_int 27 [0x1b])
(const_int 28 [0x1c])
(const_int 29 [0x1d])
(const_int 30 [0x1e])
(const_int 31 [0x1f])
]))) "pr109780.c":11:12 -1
(nil))
(insn 25 24 0 (set (mem/c:DI (plus:DI (reg:DI 107)
(const_int 32 [0x20])) [0 MEM <char[1:40]> [(void *)&k]+32 S8
A128])
(subreg:DI (reg:V32QI 108) 0)) "pr109780.c":11:12 -1
(nil))
