[Bug target/50135] Loop optimization.

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50135

Uros Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |SUSPENDED
   Last reconfirmed|                            |2011-08-21
     Ever Confirmed|0                           |1

--- Comment #2 from Uros Bizjak <ubizjak at gmail dot com> 2011-08-21 10:25:31 UTC ---
Don't worry about loop insn, it is *SLOW* on every half-decent recent
processor, see instruction_tables.pdf at [1]. OTOH, the insn has only short
jump displacement, so you are out of luck for every loop larger than 128 bytes.

So, until x86 implements something like powerpc bdnz insn, there will be no
doloop_* patterns.

[1] http://agner.org/optimize/