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* [Bug other/17107] New: Opportunity to improve code generated for complex logical expression
@ 2004-08-19 14:59 gcc-bugzilla at gcc dot gnu dot org
  2004-08-19 15:29 ` [Bug rtl-optimization/17107] " pinskia at gcc dot gnu dot org
                   ` (7 more replies)
  0 siblings, 8 replies; 9+ messages in thread
From: gcc-bugzilla at gcc dot gnu dot org @ 2004-08-19 14:59 UTC (permalink / raw)
  To: gcc-bugs

Description:
A non-optimal code sequence is illustraded.    Duplicate using gcc 3.5 and
command line:

gcc -O3 -m64 -c test.c


Testcase:
int i;
void foo(int a, int b, int c) {

  i = (a > b && a < c);

}

Assembly:
Currently gcc 3.5 generates the following code which always results
in the execution of the compare/branch for the right side of the
expression (i.e. a < c):

.foo:
      cmpw 7,4,3
      cmpw 6,3,5
      ld 11,.LC0@toc(2)
      li 9,1
      blt- 7,.L2
      li 9,0
.L2:
      li 0,1
      blt- 6,.L3
      li 0,0
.L3:
      and 0,9,0
      stw 0,0(11)
      blr

Execution of the second compare/branch may be avoided by
restructuring the code.  This also eliminates the need for
the 'and':

.foo:
      cmpw 7,4,3
      ld 11,.LC0@toc(2)
      li 9,0
      bng- 7,.L2
      cmpw 6,3,5
      bnl- 6,.L2
      li 9,1
.L2:
      stw 9,0(11)
      blr



-- 
           Summary: Opportunity to improve code generated for complex
                    logical expression
           Product: gcc
           Version: 3.5.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P1
         Component: other
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: steinmtz at us dot ibm dot com
                CC: gcc-bugs at gcc dot gnu dot org,steinmtz at us dot ibm
                    dot com
 GCC build triplet: powerpc64-linux
  GCC host triplet: powerpc64-linux
GCC target triplet: powerpc64-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17107


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug rtl-optimization/17107] Opportunity to improve code generated for complex logical expression
  2004-08-19 14:59 [Bug other/17107] New: Opportunity to improve code generated for complex logical expression gcc-bugzilla at gcc dot gnu dot org
@ 2004-08-19 15:29 ` pinskia at gcc dot gnu dot org
  2004-10-12 10:38 ` nathan at gcc dot gnu dot org
                   ` (6 subsequent siblings)
  7 siblings, 0 replies; 9+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-08-19 15:29 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From pinskia at gcc dot gnu dot org  2004-08-19 15:29 -------
Confirmed.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
          Component|other                       |rtl-optimization
     Ever Confirmed|                            |1
           Keywords|                            |missed-optimization
   Last reconfirmed|0000-00-00 00:00:00         |2004-08-19 15:29:16
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17107


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug rtl-optimization/17107] Opportunity to improve code generated for complex logical expression
  2004-08-19 14:59 [Bug other/17107] New: Opportunity to improve code generated for complex logical expression gcc-bugzilla at gcc dot gnu dot org
  2004-08-19 15:29 ` [Bug rtl-optimization/17107] " pinskia at gcc dot gnu dot org
@ 2004-10-12 10:38 ` nathan at gcc dot gnu dot org
  2004-11-12 14:48 ` nathan at gcc dot gnu dot org
                   ` (5 subsequent siblings)
  7 siblings, 0 replies; 9+ messages in thread
From: nathan at gcc dot gnu dot org @ 2004-10-12 10:38 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From nathan at gcc dot gnu dot org  2004-10-12 10:38 -------
It occurs to me that converting && to & (when safe) is a lose on targets that
do not have setcond instructions.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17107


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug rtl-optimization/17107] Opportunity to improve code generated for complex logical expression
  2004-08-19 14:59 [Bug other/17107] New: Opportunity to improve code generated for complex logical expression gcc-bugzilla at gcc dot gnu dot org
  2004-08-19 15:29 ` [Bug rtl-optimization/17107] " pinskia at gcc dot gnu dot org
  2004-10-12 10:38 ` nathan at gcc dot gnu dot org
@ 2004-11-12 14:48 ` nathan at gcc dot gnu dot org
  2004-11-15  2:39 ` pinskia at gcc dot gnu dot org
                   ` (4 subsequent siblings)
  7 siblings, 0 replies; 9+ messages in thread
From: nathan at gcc dot gnu dot org @ 2004-11-12 14:48 UTC (permalink / raw)
  To: gcc-bugs



-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |nathan at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17107


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug rtl-optimization/17107] Opportunity to improve code generated for complex logical expression
  2004-08-19 14:59 [Bug other/17107] New: Opportunity to improve code generated for complex logical expression gcc-bugzilla at gcc dot gnu dot org
                   ` (2 preceding siblings ...)
  2004-11-12 14:48 ` nathan at gcc dot gnu dot org
@ 2004-11-15  2:39 ` pinskia at gcc dot gnu dot org
  2004-11-18 12:11 ` cvs-commit at gcc dot gnu dot org
                   ` (3 subsequent siblings)
  7 siblings, 0 replies; 9+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-11-15  2:39 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From pinskia at gcc dot gnu dot org  2004-11-15 02:39 -------
The reason why we convert TRUTH_ANDIF_EXPR to be TRUTH_AND_EXPR is because the BRANCH_COST 
is 2 on PPC. (this is done in fold-const.c).

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17107


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug rtl-optimization/17107] Opportunity to improve code generated for complex logical expression
  2004-08-19 14:59 [Bug other/17107] New: Opportunity to improve code generated for complex logical expression gcc-bugzilla at gcc dot gnu dot org
                   ` (3 preceding siblings ...)
  2004-11-15  2:39 ` pinskia at gcc dot gnu dot org
@ 2004-11-18 12:11 ` cvs-commit at gcc dot gnu dot org
  2004-11-18 12:14 ` nathan at gcc dot gnu dot org
                   ` (2 subsequent siblings)
  7 siblings, 0 replies; 9+ messages in thread
From: cvs-commit at gcc dot gnu dot org @ 2004-11-18 12:11 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-11-18 12:10 -------
Subject: Bug 17107

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	nathan@gcc.gnu.org	2004-11-18 12:09:45

Modified files:
	gcc            : ChangeLog fold-const.c 
	gcc/config/rs6000: rs6000.h 

Log message:
	PR target/17107
	* fold-const.c (RANGE_TEST_NON_SHORT_CIRCUIT): Rename to ...
	(LOGICAL_OP_NON_SHORT_CIRCUIT): ... here.
	(fold_range_test): Adjust.
	(fold_truthop): Use it.
	* config/rs6000/rs6000.h (RANGE_TEST_NON_SHORT_CIRCUIT): Rename to ...
	(LOGICAL_OP_NON_SHORT_CIRCUIT): ... here.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.6393&r2=2.6394
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/fold-const.c.diff?cvsroot=gcc&r1=1.474&r2=1.475
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/config/rs6000/rs6000.h.diff?cvsroot=gcc&r1=1.346&r2=1.347



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17107


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug rtl-optimization/17107] Opportunity to improve code generated for complex logical expression
  2004-08-19 14:59 [Bug other/17107] New: Opportunity to improve code generated for complex logical expression gcc-bugzilla at gcc dot gnu dot org
                   ` (4 preceding siblings ...)
  2004-11-18 12:11 ` cvs-commit at gcc dot gnu dot org
@ 2004-11-18 12:14 ` nathan at gcc dot gnu dot org
  2004-11-18 12:16 ` pinskia at gcc dot gnu dot org
  2004-12-01 17:19 ` cvs-commit at gcc dot gnu dot org
  7 siblings, 0 replies; 9+ messages in thread
From: nathan at gcc dot gnu dot org @ 2004-11-18 12:14 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From nathan at gcc dot gnu dot org  2004-11-18 12:14 -------
2004-11-18  Nathan Sidwell  <nathan@codesourcery.com>

	PR target/17107
	* fold-const.c (RANGE_TEST_NON_SHORT_CIRCUIT): Rename to ...
	(LOGICAL_OP_NON_SHORT_CIRCUIT): ... here.
	(fold_range_test): Adjust.
	(fold_truthop): Use it.
	* config/rs6000/rs6000.h (RANGE_TEST_NON_SHORT_CIRCUIT): Rename to ...
	(LOGICAL_OP_NON_SHORT_CIRCUIT): ... here.


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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17107


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug rtl-optimization/17107] Opportunity to improve code generated for complex logical expression
  2004-08-19 14:59 [Bug other/17107] New: Opportunity to improve code generated for complex logical expression gcc-bugzilla at gcc dot gnu dot org
                   ` (5 preceding siblings ...)
  2004-11-18 12:14 ` nathan at gcc dot gnu dot org
@ 2004-11-18 12:16 ` pinskia at gcc dot gnu dot org
  2004-12-01 17:19 ` cvs-commit at gcc dot gnu dot org
  7 siblings, 0 replies; 9+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-11-18 12:16 UTC (permalink / raw)
  To: gcc-bugs



-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.0.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17107


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [Bug rtl-optimization/17107] Opportunity to improve code generated for complex logical expression
  2004-08-19 14:59 [Bug other/17107] New: Opportunity to improve code generated for complex logical expression gcc-bugzilla at gcc dot gnu dot org
                   ` (6 preceding siblings ...)
  2004-11-18 12:16 ` pinskia at gcc dot gnu dot org
@ 2004-12-01 17:19 ` cvs-commit at gcc dot gnu dot org
  7 siblings, 0 replies; 9+ messages in thread
From: cvs-commit at gcc dot gnu dot org @ 2004-12-01 17:19 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-12-01 17:19 -------
Subject: Bug 17107

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	dje@gcc.gnu.org	2004-12-01 17:18:43

Modified files:
	gcc            : ChangeLog 
	gcc/config/rs6000: rs6000.md 

Log message:
	2004-12-01  David Edelsohn  <edelsohn@gnu.org>
	Nathan Sidwell  <nathan@codesourcery.com>
	
	PR target/17107
	* config/rs6000/rs6000.md (sge): Enable for non-TARGET_POWER.
	(sgt): Same.
	(sle): Same.
	(slt): Same.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.6659&r2=2.6660
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/config/rs6000/rs6000.md.diff?cvsroot=gcc&r1=1.335&r2=1.336



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17107


^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2004-12-01 17:19 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2004-08-19 14:59 [Bug other/17107] New: Opportunity to improve code generated for complex logical expression gcc-bugzilla at gcc dot gnu dot org
2004-08-19 15:29 ` [Bug rtl-optimization/17107] " pinskia at gcc dot gnu dot org
2004-10-12 10:38 ` nathan at gcc dot gnu dot org
2004-11-12 14:48 ` nathan at gcc dot gnu dot org
2004-11-15  2:39 ` pinskia at gcc dot gnu dot org
2004-11-18 12:11 ` cvs-commit at gcc dot gnu dot org
2004-11-18 12:14 ` nathan at gcc dot gnu dot org
2004-11-18 12:16 ` pinskia at gcc dot gnu dot org
2004-12-01 17:19 ` cvs-commit at gcc dot gnu dot org

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