https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122592
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target|aarch64 |aarch64-linux-gnu
--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The other thing is:
```
Trying 4 -> 13:
4: r107:SI=zero_extend(x2:HI)
REG_DEAD x2:HI
13: x0:SI=zero_extend(x1:HI)+r107:SI
REG_DEAD r107:SI
REG_DEAD x1:HI
Failed to match this instruction:
(set (reg/i:SI 0 x0)
(plus:SI (zero_extend:SI (reg:HI 1 x1 [ a ]))
(zero_extend:SI (reg:HI 2 x2 [ b ]))))
```
Maybe should be matched and then expanded into:
```
(set (reg:SI t)
(plus:SI (subreg:SI (reg:HI 1 x1 [ a ]))
(subreg:SI (reg:HI 2 x2 [ b ])))
(set (reg/i:SI 0 x0)
(zero_extend:SI (subreg:HI (reg:SI t)))
```
that will move the zero extend all the way down.
