https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114190
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever confirmed|0 |1
Last reconfirmed| |2024-03-01
Component|target |rtl-optimization
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
cmpelim produces:
```
(insn 22 21 486 2 (set (reg:CCZ 17 flags)
(compare:CCZ (reg:SI 4 si [orig:111 _21+4 ] [111])
(const_int 0 [0]))) "/app/example.cpp":8:8 discrim 1 7
{*cmpsi_ccno_1}
(expr_list:REG_UNUSED (reg:CCZ 17 flags)
(nil)))
(insn 486 22 466 2 (set (reg:DI 1 dx [353])
(plus:DI (reg/f:DI 7 sp)
(const_int 212 [0xd4]))) "/app/example.cpp":8:65 discrim 1 254
{*leadi}
(nil))
(insn 466 486 383 2 (set (reg:DI 4 si [354])
(const:DI (plus:DI (symbol_ref:DI ("u") [flags 0x2] <var_decl
0x7fe775410c60 u>)
(const_int 1 [0x1])))) "/app/example.cpp":8:65 discrim 1 84
{*movdi_internal}
(expr_list:REG_EQUIV (const:DI (plus:DI (symbol_ref:DI ("u") [flags 0x2]
<var_decl 0x7fe775410c60 u>)
(const_int 1 [0x1])))
(nil)))
(insn 383 466 384 2 (set (reg:DI 1 dx [348])
(if_then_else:DI (eq (reg:CCZ 17 flags)
(const_int 0 [0]))
(reg:DI 1 dx [353])
(reg:DI 4 si [354]))) "/app/example.cpp":8:65 discrim 1 1451
{*movdicc_noc}
(expr_list:REG_DEAD (reg:CCZ 17 flags)
(expr_list:REG_DEAD (reg:DI 4 si [354])
(nil))))
```
Which is fine (but note the REG_UNUSED note which was not updated).
>From pro_and_epilogue's dump:
deleting insn with uid = 22.
Which is totally bogus; I think someone didn't redo REG_UNUSED notes again.
