https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66489
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
See Also| |https://gcc.gnu.org/bugzill
| |a/show_bug.cgi?id=85160
Resolution|--- |FIXED
Status|NEW |RESOLVED
Target Milestone|--- |9.0
--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Fixed in GCC 9 with 2->2 combing being done now (r9-2064-gc4c5ad1d6d1e1e1fe7a):
Trying 11 -> 12:
11: r96:SI=-r115:SI
REG_DEAD r115:SI
12: r108:SI=r96:SI*r103:SI
Failed to match this instruction:
(parallel [
(set (reg:SI 108)
(mult:SI (neg:SI (reg:SI 115))
(reg/v:SI 103 [ cD.4384 ])))
(set (reg/v:SI 96 [ aD.4382 ])
(neg:SI (reg:SI 115)))
])
Failed to match this instruction:
(parallel [
(set (reg:SI 108)
(mult:SI (neg:SI (reg:SI 115))
(reg/v:SI 103 [ cD.4384 ])))
(set (reg/v:SI 96 [ aD.4382 ])
(neg:SI (reg:SI 115)))
])
Successfully matched this instruction:
(set (reg/v:SI 96 [ aD.4382 ])
(neg:SI (reg:SI 115)))
Successfully matched this instruction:
(set (reg:SI 108)
(mult:SI (neg:SI (reg:SI 115))
(reg/v:SI 103 [ cD.4384 ])))
allowing combination of insns 11 and 12
original costs 4 + 12 = 16
replacement costs 4 + 12 = 16
modifying insn i2 11: r96:SI=-r115:SI
deferring rescan insn with uid = 11.
modifying insn i3 12: r108:SI=-r115:SI*r103:SI
REG_DEAD r115:SI
deferring rescan insn with uid = 12.
