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* [Bug target/16494] New: [3.3.2/3.4/3.5] Pessimization with FP conditional branches
@ 2004-07-12 12:59 ebotcazou at gcc dot gnu dot org
  2004-07-12 13:01 ` [Bug target/16494] " ebotcazou at gcc dot gnu dot org
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2004-07-12 12:59 UTC (permalink / raw)
  To: gcc-bugs

On non-V9 targets, when delay slots are not filled, FP conditional branches are
unnecessarily reversed:

[eric@localhost obj.sparc]$ cat t.c
int foo(float f1, float f2)
{
  if (f1 > f2)
    return 0;
  else
    return 1;
}

[eric@localhost obj.sparc]$ gcc/cc1 -Bgcc t.c -mcpu=v7 -O2 -fno-delayed-branch
[eric@localhost obj.sparc]$ cat t.s
        .file   "t.c"
        .section        ".text"
        .align 4
        .global foo
        .type   foo, #function
        .proc   04
foo:
        !#PROLOGUE# 0
        add     %sp, -120, %sp
        !#PROLOGUE# 1
        st      %o0, [%sp+100]
        ld      [%sp+100], %f9
        st      %o1, [%sp+100]
        ld      [%sp+100], %f8
        fcmpes  %f9, %f8
        mov     0, %o0
        nop
        fbule   .+16
        nop
        b       .LL1
        nop
        mov     1, %o0
.LL1:
        retl
        sub     %sp, -120, %sp
        .size   foo, .-foo
        .ident  "GCC: (GNU) 3.3.5 20040703 (prerelease)"

The expected assembly output is:

        .file   "t.c"
        .section        ".text"
        .align 4
        .global foo
        .type   foo, #function
        .proc   04
foo:
        !#PROLOGUE# 0
        add     %sp, -120, %sp
        !#PROLOGUE# 1
        st      %o0, [%sp+100]
        ld      [%sp+100], %f9
        st      %o1, [%sp+100]
        ld      [%sp+100], %f8
        fcmpes  %f9, %f8
        mov     0, %o0
        nop
        fbg     .LL1
        nop
        mov     1, %o0
.LL1:
        retl
        sub     %sp, -120, %sp
        .size   foo, .-foo
        .ident  "GCC: (GNU) 3.3.5 20040703 (prerelease)"


This was inadvertently introduced by:

2003-10-01  Eric Botcazou  <ebotcazou@libertysurf.fr>

	PR optimization/11753
	* config/sparc/sparc.md (length attribute) [fcc branch]: Add 1 to
	the length in the non-V9 case.

because there is an undocumented side-effect associated with having a length
greater or equal to 3 for FP conditional branches.

-- 
           Summary: [3.3.2/3.4/3.5] Pessimization with FP conditional
                    branches
           Product: gcc
           Version: 3.3.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: ebotcazou at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: sparc-*-*
  GCC host triplet: sparc-*-*
GCC target triplet: sparc-*-*


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16494


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/16494] [3.3.2/3.4/3.5] Pessimization with FP conditional branches
  2004-07-12 12:59 [Bug target/16494] New: [3.3.2/3.4/3.5] Pessimization with FP conditional branches ebotcazou at gcc dot gnu dot org
@ 2004-07-12 13:01 ` ebotcazou at gcc dot gnu dot org
  2004-07-13 12:09 ` cvs-commit at gcc dot gnu dot org
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2004-07-12 13:01 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From ebotcazou at gcc dot gnu dot org  2004-07-12 13:01 -------
Fixing.


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |ebotcazou at gcc dot gnu dot
                   |dot org                     |org
             Status|UNCONFIRMED                 |ASSIGNED
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2004-07-12 13:01:27
               date|                            |
   Target Milestone|---                         |3.3.5


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16494


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/16494] [3.3.2/3.4/3.5] Pessimization with FP conditional branches
  2004-07-12 12:59 [Bug target/16494] New: [3.3.2/3.4/3.5] Pessimization with FP conditional branches ebotcazou at gcc dot gnu dot org
  2004-07-12 13:01 ` [Bug target/16494] " ebotcazou at gcc dot gnu dot org
@ 2004-07-13 12:09 ` cvs-commit at gcc dot gnu dot org
  2004-07-13 12:14 ` cvs-commit at gcc dot gnu dot org
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: cvs-commit at gcc dot gnu dot org @ 2004-07-13 12:09 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-07-13 12:09 -------
Subject: Bug 16494

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	ebotcazou@gcc.gnu.org	2004-07-13 12:08:57

Modified files:
	gcc            : ChangeLog 
	gcc/config/sparc: sparc.c sparc.md 

Log message:
	PR target/16494
	* config/sparc/sparc.c (output_cbranch): Properly guard
	the code handling far branches with TARGET_V9.
	* config/sparc/sparc.md (length attribute): Document the
	side-effect of having a length greater or equal to 3.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.4503&r2=2.4504
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/config/sparc/sparc.c.diff?cvsroot=gcc&r1=1.319&r2=1.320
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/config/sparc/sparc.md.diff?cvsroot=gcc&r1=1.211&r2=1.212



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16494


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/16494] [3.3.2/3.4/3.5] Pessimization with FP conditional branches
  2004-07-12 12:59 [Bug target/16494] New: [3.3.2/3.4/3.5] Pessimization with FP conditional branches ebotcazou at gcc dot gnu dot org
  2004-07-12 13:01 ` [Bug target/16494] " ebotcazou at gcc dot gnu dot org
  2004-07-13 12:09 ` cvs-commit at gcc dot gnu dot org
@ 2004-07-13 12:14 ` cvs-commit at gcc dot gnu dot org
  2004-07-13 12:18 ` cvs-commit at gcc dot gnu dot org
  2004-07-13 12:21 ` ebotcazou at gcc dot gnu dot org
  4 siblings, 0 replies; 6+ messages in thread
From: cvs-commit at gcc dot gnu dot org @ 2004-07-13 12:14 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-07-13 12:14 -------
Subject: Bug 16494

CVSROOT:	/cvs/gcc
Module name:	gcc
Branch: 	gcc-3_4-branch
Changes by:	ebotcazou@gcc.gnu.org	2004-07-13 12:14:33

Modified files:
	gcc            : ChangeLog 
	gcc/config/sparc: sparc.c sparc.md 

Log message:
	PR target/16494
	* config/sparc/sparc.c (output_cbranch): Properly guard
	the code handling far branches with TARGET_V9.
	* config/sparc/sparc.md (length attribute): Document the
	side-effect of having a length greater or equal to 3.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&only_with_tag=gcc-3_4-branch&r1=2.2326.2.554&r2=2.2326.2.555
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/config/sparc/sparc.c.diff?cvsroot=gcc&only_with_tag=gcc-3_4-branch&r1=1.271.4.17&r2=1.271.4.18
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/config/sparc/sparc.md.diff?cvsroot=gcc&only_with_tag=gcc-3_4-branch&r1=1.196.2.3&r2=1.196.2.4



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16494


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/16494] [3.3.2/3.4/3.5] Pessimization with FP conditional branches
  2004-07-12 12:59 [Bug target/16494] New: [3.3.2/3.4/3.5] Pessimization with FP conditional branches ebotcazou at gcc dot gnu dot org
                   ` (2 preceding siblings ...)
  2004-07-13 12:14 ` cvs-commit at gcc dot gnu dot org
@ 2004-07-13 12:18 ` cvs-commit at gcc dot gnu dot org
  2004-07-13 12:21 ` ebotcazou at gcc dot gnu dot org
  4 siblings, 0 replies; 6+ messages in thread
From: cvs-commit at gcc dot gnu dot org @ 2004-07-13 12:18 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-07-13 12:18 -------
Subject: Bug 16494

CVSROOT:	/cvs/gcc
Module name:	gcc
Branch: 	gcc-3_3-branch
Changes by:	ebotcazou@gcc.gnu.org	2004-07-13 12:18:30

Modified files:
	gcc            : ChangeLog 
	gcc/config/sparc: sparc.c sparc.md 

Log message:
	PR target/16494
	* config/sparc/sparc.c (output_cbranch): Properly guard
	the code handling far branches with TARGET_V9.
	* config/sparc/sparc.md (length attribute): Document the
	side-effect of having a length greater or equal to 3.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&only_with_tag=gcc-3_3-branch&r1=1.16114.2.1000&r2=1.16114.2.1001
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/config/sparc/sparc.c.diff?cvsroot=gcc&only_with_tag=gcc-3_3-branch&r1=1.233.4.10&r2=1.233.4.11
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/config/sparc/sparc.md.diff?cvsroot=gcc&only_with_tag=gcc-3_3-branch&r1=1.181.4.11&r2=1.181.4.12



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16494


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/16494] [3.3.2/3.4/3.5] Pessimization with FP conditional branches
  2004-07-12 12:59 [Bug target/16494] New: [3.3.2/3.4/3.5] Pessimization with FP conditional branches ebotcazou at gcc dot gnu dot org
                   ` (3 preceding siblings ...)
  2004-07-13 12:18 ` cvs-commit at gcc dot gnu dot org
@ 2004-07-13 12:21 ` ebotcazou at gcc dot gnu dot org
  4 siblings, 0 replies; 6+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2004-07-13 12:21 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From ebotcazou at gcc dot gnu dot org  2004-07-13 12:21 -------
See http://gcc.gnu.org/ml/gcc-patches/2004-07/msg01333.html


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16494


^ permalink raw reply	[flat|nested] 6+ messages in thread

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2004-07-12 12:59 [Bug target/16494] New: [3.3.2/3.4/3.5] Pessimization with FP conditional branches ebotcazou at gcc dot gnu dot org
2004-07-12 13:01 ` [Bug target/16494] " ebotcazou at gcc dot gnu dot org
2004-07-13 12:09 ` cvs-commit at gcc dot gnu dot org
2004-07-13 12:14 ` cvs-commit at gcc dot gnu dot org
2004-07-13 12:18 ` cvs-commit at gcc dot gnu dot org
2004-07-13 12:21 ` ebotcazou at gcc dot gnu dot org

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