[Bug target/114134] [14 Regression] Extra mov instructions for simple function compared with GCC13

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114134

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2024-02-28

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Looks like the biggest issue is when expanding:
;; return D.26244;


Before:

(insn 34 33 35 (set (subreg:DI (reg:TI 107) 8)
        (reg:DI 108)) "/app/example.cpp":14:47 discrim 1 -1
     (nil))

(insn 35 34 36 (set (reg:TI 98 [ <retval> ])
        (reg:TI 107)) "/app/example.cpp":14:47 discrim 1 -1
     (nil))

After:
(insn 41 40 42 (set (reg:TI 130)
        (ior:TI (and:TI (reg:TI 130)
                (const_wide_int 0x0ffffffffffffffff))
            (ashift:TI (zero_extend:TI (reg:DI 131))
                (const_int 64 [0x40])))) "/app/example.cpp":14:47 discrim 1 -1
     (nil))

(insn 42 41 43 (set (reg:TI 114 [ <retval> ])
        (reg:TI 130)) "/app/example.cpp":14:47 discrim 1 -1
     (nil))