------- Comment #1 from rguenth at gcc dot gnu dot org 2010-01-03 11:27 -------
Confirmed. Well, GCC produces exactly the same code as ICC when using
-O2 -mno-accumulate-outgoing-args -fno-optimize-sibling-calls
-fomit-frame-pointer
Thus the sibcall comes in the way as obviously does -maccumulate-outgoing-args.
w/o -maccumulate-outgoing-args but the rest of the options we produce
Perl_sv_vsetpvfn:
pushl %ebx
subl $40, %esp
movl 48(%esp), %ebx
movl $0, 8(%esp)
movl $.LC0, 4(%esp)
movl %ebx, (%esp)
call Perl_sv_setpvn
movl 72(%esp), %eax
movl %ebx, (%esp)
movl %eax, 24(%esp)
movl 68(%esp), %eax
movl %eax, 20(%esp)
movl 64(%esp), %eax
movl %eax, 16(%esp)
movl 60(%esp), %eax
movl %eax, 12(%esp)
movl 56(%esp), %eax
movl %eax, 8(%esp)
movl 52(%esp), %eax
movl %eax, 4(%esp)
call Perl_sv_vcatpvfn
addl $40, %esp
popl %ebx
ret
which looks like we cannot do better with that constraint. The sibcall
variant isn't too bad either.
Of course with sibcalling and -mno-accumulate-outgoing-args we fail to
re-order argument setup for optimal size, even with -fschedule-insns.
So that part of the bug would be valid.
--
rguenth at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |vmakarov at redhat dot com
Severity|normal |enhancement
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Keywords| |missed-optimization, ra
Last reconfirmed|0000-00-00 00:00:00 |2010-01-03 11:27:29
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42592
