[Bug rtl-optimization/41171] register allocator undoing optimal schedule

[nemet at gcc dot gnu dot org]

------- Comment #1 from nemet at gcc dot gnu dot org  2009-08-25 23:05 -------
It's also a regression if the load-immediates can dual issue.  I.e. see below
how the code gets worse between sched1 and sched2 on octeon.

I am cc'ing Vlad in case he has some ideas.



;;   ======================================================
;;   -- basic block 2 from 7 to 10 -- before reload
;;   ======================================================

;;        0-->     7 r195=0x7                         
:octeon_pipe0|octeon_pipe1
;;        0-->     9 r196=0x4                         
:octeon_pipe0|octeon_pipe1
;;        1-->     8 [$4]=r195                         :octeon_pipe0
;;        2-->    10 [$5]=r196                         :octeon_pipe0
;;      Ready list (final):  
;;   total time = 2
;;   new head = 7
;;   new tail = 10


;; Procedure interblock/speculative motions == 0/0 


;;   ======================================================
;;   -- basic block 2 from 7 to 18 -- after reload
;;   ======================================================

;;        0-->     7 $2=0x7                           
:octeon_pipe0|octeon_pipe1
;;        1-->     8 [$4]=$2                           :octeon_pipe0
;;        1-->    14 $2=0x4                           
:octeon_pipe0|octeon_pipe1
;;        2-->    10 [$5]=$2                           :octeon_pipe0
;;        3-->    18 return                            :octeon_pipe0
;;      Ready list (final):  
;;   total time = 3
;;   new head = 7
;;   new tail = 18


-- 

nemet at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |vmakarov at gcc dot gnu dot
                   |                            |org, nemet at gcc dot gnu
                   |                            |dot org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2009-08-25 23:05:53
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41171