https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119901
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Last reconfirmed| |2025-04-22
Ever confirmed|0 |1
Status|UNCONFIRMED |NEW
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
-favoid-store-forwarding produces worse code too.
(insn 12 7 13 2 (set (mem/c:V16QI (symbol_ref:DI ("v") [flags 0x2] <var_decl
0x7d090fe01e40 v>) [0 MEM <char[1:32]> [(void *)&v]+0 S16 A256])
(subreg:V16QI (reg:V4SI 105) 0)) "/app/example.cpp":8:15 2397
{movv16qi_internal}
(nil))
(insn 13 12 15 2 (set (mem/c:V16QI (const:DI (plus:DI (symbol_ref:DI ("v")
[flags 0x2] <var_decl 0x7d090fe01e40 v>)
(const_int 16 [0x10]))) [0 MEM <char[1:32]> [(void *)&v]+16
S16 A128])
(subreg:V16QI (reg:V4SI 105) 0)) "/app/example.cpp":8:15 2397
{movv16qi_internal}
(expr_list:REG_DEAD (reg:V4SI 105)
(nil)))
(insn 15 13 16 2 (set (reg:V16HI 99 [ _2 ])
(mem:V16HI (symbol_ref:DI ("v") [flags 0x2] <var_decl 0x7d090fe01e40
v>) [1 MEM[(V *)_1]+0 S32 A256])) "/app/example.cpp":8:8 discrim 1 2399
{movv16hi_internal}
(nil))
Into:
(insn 25 21 23 2 (set (mem/c:V16QI (symbol_ref:DI ("v") [flags 0x2] <var_decl
0x7ba267c01e40 v>) [0 MEM <char[1:32]> [(void *)&v]+0 S16 A256])
(reg:V16QI 110)) "/app/example.cpp":8:8 discrim 1 2397
{movv16qi_internal}
(nil))
(insn 23 25 22 2 (set (reg:V16HI 108)
(zero_extend:V16HI (reg:V16QI 110))) "/app/example.cpp":8:8 discrim 1
8682 {avx2_zero_extendv16qiv16hi2}
(nil))
(insn 22 23 20 2 (set (mem/c:V16QI (const:DI (plus:DI (symbol_ref:DI ("v")
[flags 0x2] <var_decl 0x7ba267c01e40 v>)
(const_int 16 [0x10]))) [0 MEM <char[1:32]> [(void *)&v]+16
S16 A128])
(reg:V16QI 109)) "/app/example.cpp":8:8 discrim 1 2397
{movv16qi_internal}
(nil))
(insn 20 22 26 2 (set (subreg:V16QI (reg:V16HI 108) 16)
(reg:V16QI 109)) "/app/example.cpp":8:8 discrim 1 2397
{movv16qi_internal}
(nil))
(insn 26 20 16 2 (set (reg:V16HI 99 [ _2 ])
(reg:V16HI 108)) "/app/example.cpp":8:8 discrim 1 2399
{movv16hi_internal}
(nil))
(insn 16 26 0 2 (set (mem:V16HI (reg/f:DI 107 [ r ]) [1 *r_5(D)+0 S32 A256])
(reg:V16HI 99 [ _2 ])) "/app/example.cpp":8:6 discrim 1 2399
{movv16hi_internal}
(expr_list:REG_DEAD (reg/f:DI 107 [ r ])
(expr_list:REG_DEAD (reg:V16HI 99 [ _2 ])
(nil))))
