public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
@ 2005-10-25 20:18 ` pinskia at gcc dot gnu dot org
  2005-10-27 16:26 ` steven at gcc dot gnu dot org
                   ` (12 subsequent siblings)
  13 siblings, 0 replies; 14+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-10-25 20:18 UTC (permalink / raw)
  To: gcc-bugs



-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |minor
          Component|rtl-optimization            |target
           Keywords|                            |missed-optimization
            Summary|bigger version of mov + cmp |[4.1 Regression]bigger
                   |produced                    |version of mov + cmp
                   |                            |produced
   Target Milestone|---                         |4.1.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
  2005-10-25 20:18 ` [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced pinskia at gcc dot gnu dot org
@ 2005-10-27 16:26 ` steven at gcc dot gnu dot org
  2005-10-27 16:43 ` dann at godzilla dot ics dot uci dot edu
                   ` (11 subsequent siblings)
  13 siblings, 0 replies; 14+ messages in thread
From: steven at gcc dot gnu dot org @ 2005-10-27 16:26 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #7 from steven at gcc dot gnu dot org  2005-10-27 16:26 -------
Could the dear reported at least try to provide a small test case?

I think this should not be marked as a regression.  It's just sad that this
kind of non-bug keeps the regression count high, when in reality GCC 4.1
produces smaller code overall.



-- 

steven at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |WAITING


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
  2005-10-25 20:18 ` [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced pinskia at gcc dot gnu dot org
  2005-10-27 16:26 ` steven at gcc dot gnu dot org
@ 2005-10-27 16:43 ` dann at godzilla dot ics dot uci dot edu
  2005-10-27 17:08 ` steven at gcc dot gnu dot org
                   ` (10 subsequent siblings)
  13 siblings, 0 replies; 14+ messages in thread
From: dann at godzilla dot ics dot uci dot edu @ 2005-10-27 16:43 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #8 from dann at godzilla dot ics dot uci dot edu  2005-10-27 16:43 -------
(In reply to comment #7)
> Could the dear reported at least try to provide a small test case?

The testcase in the attachment contains only a 4 lines function: 
HandleDeIconify, the rest is just fluff to allow it to compile. Granted a lot
of it can be pruned, but I don't think it stops trying to debug the problem.


> I think this should not be marked as a regression.  

Why not? It is a regression. 

> It's just sad that this
> kind of non-bug keeps the regression count high, when in reality GCC 4.1
> produces smaller code overall.

PR23153 tells a completely different story about codesize (at least for i686).


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
                   ` (2 preceding siblings ...)
  2005-10-27 16:43 ` dann at godzilla dot ics dot uci dot edu
@ 2005-10-27 17:08 ` steven at gcc dot gnu dot org
  2005-10-27 17:31 ` steven at gcc dot gnu dot org
                   ` (9 subsequent siblings)
  13 siblings, 0 replies; 14+ messages in thread
From: steven at gcc dot gnu dot org @ 2005-10-27 17:08 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #9 from steven at gcc dot gnu dot org  2005-10-27 17:08 -------
And CSiBE tells you the story that GCC 4.1 produces smaller code overall.
http://www.inf.u-szeged.hu/csibe/draw-diag.php?draw=sum-os&basephp=s-i686-linux

So do the SPEC benchmark boxes btw.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
                   ` (3 preceding siblings ...)
  2005-10-27 17:08 ` steven at gcc dot gnu dot org
@ 2005-10-27 17:31 ` steven at gcc dot gnu dot org
  2005-10-27 17:34 ` steven at gcc dot gnu dot org
                   ` (8 subsequent siblings)
  13 siblings, 0 replies; 14+ messages in thread
From: steven at gcc dot gnu dot org @ 2005-10-27 17:31 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #10 from steven at gcc dot gnu dot org  2005-10-27 17:31 -------
For the record, we're talking about:

   1                            .file   "t.c"
   2                            .text
   3                            .p2align 4,,15
   4                    .globl foo
   5                            .type   foo, @function
   6                    foo:
   7 0000 55                    pushl   %ebp
   8 0001 A1000000              movl    x, %eax
   8      00
   9 0006 89E5                  movl    %esp, %ebp
  10 0008 8B5508                movl    8(%ebp), %edx
  11 000b 394204                cmpl    %eax, 4(%edx)
  12 000e 7402                  je      .L4
  13 0010 5D                    popl    %ebp
  14 0011 C3                    ret
  15                            .p2align 4,,7
  16                    .L4:
  17 0012 5D                    popl    %ebp
  18 0013 E9FCFFFF              jmp     bar
  18      FF
  19                            .size   foo, .-foo
  20                            .comm   x,4,4
  21                            .section        .note.GNU-stack,"",@progbits
  22                            .ident  "GCC: (GNU) 3.3.4 (pre 3.3.5 20040809)"




vs.


   1                            .file   "t.c"
   2                            .text
   3                            .p2align 4,,15
   4                    .globl foo
   5                            .type   foo, @function
   6                    foo:
   7 0000 55                    pushl   %ebp
   8 0001 89E5                  movl    %esp, %ebp
   9 0003 8B5508                movl    8(%ebp), %edx
  10 0006 8B4204                movl    4(%edx), %eax
  11 0009 3B050000              cmpl    x, %eax
  11      0000
  12 000f 7402                  je      .L6
  13 0011 5D                    popl    %ebp
  14 0012 C3                    ret
  15                            .p2align 4,,7
  16                    .L6:
  17 0013 5D                    popl    %ebp
  18 0014 E9FCFFFF              jmp     bar
  18      FF
  19                            .size   foo, .-foo
  20                            .comm   x,4,4
  21                            .ident  "GCC: (GNU) 4.1.0 20051026
(experimental)"
  22                            .section        .note.GNU-stack,"",@progbits


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
                   ` (4 preceding siblings ...)
  2005-10-27 17:31 ` steven at gcc dot gnu dot org
@ 2005-10-27 17:34 ` steven at gcc dot gnu dot org
  2005-10-27 17:35 ` steven at gcc dot gnu dot org
                   ` (7 subsequent siblings)
  13 siblings, 0 replies; 14+ messages in thread
From: steven at gcc dot gnu dot org @ 2005-10-27 17:34 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #11 from steven at gcc dot gnu dot org  2005-10-27 17:34 -------
And FWIW there is also a problem with this insn, the length is wrong:

#(insn 11 46 47 0x2a955cc840 (set (reg:SI 0 eax [orig:61 x ] [61])
#        (mem/f:SI (symbol_ref:SI ("x")) [5 x+0 S4 A32])) 44 {*movsi_1} (nil)
#    (expr_list:REG_EQUIV (mem/f:SI (symbol_ref:SI ("x")) [5 x+0 S4 A32])
#        (nil)))
A100000000       movl    x, %eax # 11    *movsi_1/1      [length = 6]


-- 

steven at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|0000-00-00 00:00:00         |2005-10-27 17:34:42
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
                   ` (5 preceding siblings ...)
  2005-10-27 17:34 ` steven at gcc dot gnu dot org
@ 2005-10-27 17:35 ` steven at gcc dot gnu dot org
  2005-10-27 18:08 ` dann at godzilla dot ics dot uci dot edu
                   ` (6 subsequent siblings)
  13 siblings, 0 replies; 14+ messages in thread
From: steven at gcc dot gnu dot org @ 2005-10-27 17:35 UTC (permalink / raw)
  To: gcc-bugs



-- 

steven at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|2005-10-27 17:34:42         |2005-10-27 17:35:05
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
                   ` (6 preceding siblings ...)
  2005-10-27 17:35 ` steven at gcc dot gnu dot org
@ 2005-10-27 18:08 ` dann at godzilla dot ics dot uci dot edu
  2005-10-31  4:50 ` dann at godzilla dot ics dot uci dot edu
                   ` (5 subsequent siblings)
  13 siblings, 0 replies; 14+ messages in thread
From: dann at godzilla dot ics dot uci dot edu @ 2005-10-27 18:08 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #12 from dann at godzilla dot ics dot uci dot edu  2005-10-27 18:08 -------
(In reply to comment #9)
> And CSiBE tells you the story that GCC 4.1 produces smaller code overall.
> http://www.inf.u-szeged.hu/csibe/draw-diag.php?draw=sum-os&basephp=s-i686-linux

Well, it obviously depends on applications.
The point of PR23153 is to show that there is a code size regression, and all
the PRs that depend on it are showing very specific issues that cause a part of
the regression.

A more interesting test would be to see the Linux kernel size difference,
because if there's any difference there would be some people screaming
(unfortunately I won't be able to do that comparison anytime soon, hope someone
else will).


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
                   ` (7 preceding siblings ...)
  2005-10-27 18:08 ` dann at godzilla dot ics dot uci dot edu
@ 2005-10-31  4:50 ` dann at godzilla dot ics dot uci dot edu
  2005-10-31  5:36 ` mmitchel at gcc dot gnu dot org
                   ` (4 subsequent siblings)
  13 siblings, 0 replies; 14+ messages in thread
From: dann at godzilla dot ics dot uci dot edu @ 2005-10-31  4:50 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #13 from dann at godzilla dot ics dot uci dot edu  2005-10-31 04:50 -------
(In reply to comment #12)
> A more interesting test would be to see the Linux kernel size difference,

There's such a comparison now in comment #8 in PR23153. It confirms the size
increase.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
                   ` (8 preceding siblings ...)
  2005-10-31  4:50 ` dann at godzilla dot ics dot uci dot edu
@ 2005-10-31  5:36 ` mmitchel at gcc dot gnu dot org
  2005-11-03  6:29 ` uros at kss-loka dot si
                   ` (3 subsequent siblings)
  13 siblings, 0 replies; 14+ messages in thread
From: mmitchel at gcc dot gnu dot org @ 2005-10-31  5:36 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #14 from mmitchel at gcc dot gnu dot org  2005-10-31 05:36 -------
I don't think this PR is, in-and-of-itself, is very interesting, as it's a
1-byte size increase with -O2, which, as has been said, is not aimed at
minimizing code size.  So, I'm going to close this PR -- but, leave PR 23153
open, as there look to be interesting issues there.


-- 

mmitchel at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |WONTFIX


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
                   ` (9 preceding siblings ...)
  2005-10-31  5:36 ` mmitchel at gcc dot gnu dot org
@ 2005-11-03  6:29 ` uros at kss-loka dot si
  2005-11-03  6:42 ` dann at godzilla dot ics dot uci dot edu
                   ` (2 subsequent siblings)
  13 siblings, 0 replies; 14+ messages in thread
From: uros at kss-loka dot si @ 2005-11-03  6:29 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #15 from uros at kss-loka dot si  2005-11-03 06:29 -------
(In reply to comment #11)
> And FWIW there is also a problem with this insn, the length is wrong:
> 
> #(insn 11 46 47 0x2a955cc840 (set (reg:SI 0 eax [orig:61 x ] [61])
> #        (mem/f:SI (symbol_ref:SI ("x")) [5 x+0 S4 A32])) 44 {*movsi_1} (nil)
> #    (expr_list:REG_EQUIV (mem/f:SI (symbol_ref:SI ("x")) [5 x+0 S4 A32])
> #        (nil)))
> A100000000       movl    x, %eax # 11    *movsi_1/1      [length = 6]

FYI: This problem is addressed in patch at
http://gcc.gnu.org/ml/gcc-patches/2005-11/msg00116.html.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
                   ` (10 preceding siblings ...)
  2005-11-03  6:29 ` uros at kss-loka dot si
@ 2005-11-03  6:42 ` dann at godzilla dot ics dot uci dot edu
  2005-11-03 10:05 ` uros at kss-loka dot si
  2005-11-03 22:32 ` hubicka at gcc dot gnu dot org
  13 siblings, 0 replies; 14+ messages in thread
From: dann at godzilla dot ics dot uci dot edu @ 2005-11-03  6:42 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #16 from dann at godzilla dot ics dot uci dot edu  2005-11-03 06:42 -------
(In reply to comment #15)
> (In reply to comment #11)
> > And FWIW there is also a problem with this insn, the length is wrong:
> > 
> > #(insn 11 46 47 0x2a955cc840 (set (reg:SI 0 eax [orig:61 x ] [61])
> > #        (mem/f:SI (symbol_ref:SI ("x")) [5 x+0 S4 A32])) 44 {*movsi_1} (nil)
> > #    (expr_list:REG_EQUIV (mem/f:SI (symbol_ref:SI ("x")) [5 x+0 S4 A32])
> > #        (nil)))
> > A100000000       movl    x, %eax # 11    *movsi_1/1      [length = 6]
> 
> FYI: This problem is addressed in patch at
> http://gcc.gnu.org/ml/gcc-patches/2005-11/msg00116.html.

Do you know if your patch also fixes this PR?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
                   ` (11 preceding siblings ...)
  2005-11-03  6:42 ` dann at godzilla dot ics dot uci dot edu
@ 2005-11-03 10:05 ` uros at kss-loka dot si
  2005-11-03 22:32 ` hubicka at gcc dot gnu dot org
  13 siblings, 0 replies; 14+ messages in thread
From: uros at kss-loka dot si @ 2005-11-03 10:05 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #17 from uros at kss-loka dot si  2005-11-03 10:05 -------
> > FYI: This problem is addressed in patch at
> > http://gcc.gnu.org/ml/gcc-patches/2005-11/msg00116.html.
> 
> Do you know if your patch also fixes this PR?

  Unfortunatelly no... I don't know if insn size is considered during reload.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced
       [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
                   ` (12 preceding siblings ...)
  2005-11-03 10:05 ` uros at kss-loka dot si
@ 2005-11-03 22:32 ` hubicka at gcc dot gnu dot org
  13 siblings, 0 replies; 14+ messages in thread
From: hubicka at gcc dot gnu dot org @ 2005-11-03 22:32 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #18 from hubicka at gcc dot gnu dot org  2005-11-03 22:32 -------
insn size is currently completely unused.  It was used for producing loop
instructions.
Honza


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23524


^ permalink raw reply	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2005-11-03 22:32 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
     [not found] <bug-23524-1008@http.gcc.gnu.org/bugzilla/>
2005-10-25 20:18 ` [Bug target/23524] [4.1 Regression]bigger version of mov + cmp produced pinskia at gcc dot gnu dot org
2005-10-27 16:26 ` steven at gcc dot gnu dot org
2005-10-27 16:43 ` dann at godzilla dot ics dot uci dot edu
2005-10-27 17:08 ` steven at gcc dot gnu dot org
2005-10-27 17:31 ` steven at gcc dot gnu dot org
2005-10-27 17:34 ` steven at gcc dot gnu dot org
2005-10-27 17:35 ` steven at gcc dot gnu dot org
2005-10-27 18:08 ` dann at godzilla dot ics dot uci dot edu
2005-10-31  4:50 ` dann at godzilla dot ics dot uci dot edu
2005-10-31  5:36 ` mmitchel at gcc dot gnu dot org
2005-11-03  6:29 ` uros at kss-loka dot si
2005-11-03  6:42 ` dann at godzilla dot ics dot uci dot edu
2005-11-03 10:05 ` uros at kss-loka dot si
2005-11-03 22:32 ` hubicka at gcc dot gnu dot org

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).