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* [Bug optimization/14819] New: [tree-ssa] strchr is not folded at tree-level @ 2004-04-02 6:00 kazu at cs dot umass dot edu 2004-04-02 6:03 ` [Bug optimization/14819] " pinskia at gcc dot gnu dot org ` (6 more replies) 0 siblings, 7 replies; 8+ messages in thread From: kazu at cs dot umass dot edu @ 2004-04-02 6:00 UTC (permalink / raw) To: gcc-bugs Consider: extern char *strchr (__const char *__s, int __c) __attribute__ ((__pure__)); int foo (void) { int c = '1'; return (strchr ("<12ers", c) == 0); } Here is the last tree form. foo () { <bb 0>: return strchr ("<12ers", 49) == 0B; } This strchr seems to be optimized at expand time. As you might guess from the above testcase, GCC has a lot of redundant IS_EXPR_CODE_CLASS(CLASS), where CLASS is a compile-time constant. Optimizing these strchr away in turn allows us to remove a lot of dead code. It seems to be a simple extension to call simplify_builtin_strchr() from tree-ssa-ccp.c. -- Summary: [tree-ssa] strchr is not folded at tree-level Product: gcc Version: tree-ssa Status: UNCONFIRMED Keywords: pessimizes-code Severity: enhancement Priority: P2 Component: optimization AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: kazu at cs dot umass dot edu CC: gcc-bugs at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14819 ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug optimization/14819] [tree-ssa] strchr is not folded at tree-level 2004-04-02 6:00 [Bug optimization/14819] New: [tree-ssa] strchr is not folded at tree-level kazu at cs dot umass dot edu @ 2004-04-02 6:03 ` pinskia at gcc dot gnu dot org 2004-04-02 6:18 ` kazu at cs dot umass dot edu ` (5 subsequent siblings) 6 siblings, 0 replies; 8+ messages in thread From: pinskia at gcc dot gnu dot org @ 2004-04-02 6:03 UTC (permalink / raw) To: gcc-bugs ------- Additional Comments From pinskia at gcc dot gnu dot org 2004-04-02 06:03 ------- Confirmed. -- What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Ever Confirmed| |1 Last reconfirmed|0000-00-00 00:00:00 |2004-04-02 06:03:04 date| | Target Milestone|--- |tree-ssa http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14819 ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug optimization/14819] [tree-ssa] strchr is not folded at tree-level 2004-04-02 6:00 [Bug optimization/14819] New: [tree-ssa] strchr is not folded at tree-level kazu at cs dot umass dot edu 2004-04-02 6:03 ` [Bug optimization/14819] " pinskia at gcc dot gnu dot org @ 2004-04-02 6:18 ` kazu at cs dot umass dot edu 2004-04-02 14:10 ` steven at gcc dot gnu dot org ` (4 subsequent siblings) 6 siblings, 0 replies; 8+ messages in thread From: kazu at cs dot umass dot edu @ 2004-04-02 6:18 UTC (permalink / raw) To: gcc-bugs ------- Additional Comments From kazu at cs dot umass dot edu 2004-04-02 06:18 ------- Another possible place for this optimization would be fold_builtin(). -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14819 ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug optimization/14819] [tree-ssa] strchr is not folded at tree-level 2004-04-02 6:00 [Bug optimization/14819] New: [tree-ssa] strchr is not folded at tree-level kazu at cs dot umass dot edu 2004-04-02 6:03 ` [Bug optimization/14819] " pinskia at gcc dot gnu dot org 2004-04-02 6:18 ` kazu at cs dot umass dot edu @ 2004-04-02 14:10 ` steven at gcc dot gnu dot org 2004-05-21 19:44 ` [Bug tree-optimization/14819] " pinskia at gcc dot gnu dot org ` (3 subsequent siblings) 6 siblings, 0 replies; 8+ messages in thread From: steven at gcc dot gnu dot org @ 2004-04-02 14:10 UTC (permalink / raw) To: gcc-bugs ------- Additional Comments From steven at gcc dot gnu dot org 2004-04-02 14:10 ------- This should be folded in ccp. Mind if I make this my weekend project? -- What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |ASSIGNED Last reconfirmed|2004-04-02 06:03:04 |2004-04-02 14:10:29 date| | http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14819 ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug tree-optimization/14819] [tree-ssa] strchr is not folded at tree-level 2004-04-02 6:00 [Bug optimization/14819] New: [tree-ssa] strchr is not folded at tree-level kazu at cs dot umass dot edu ` (2 preceding siblings ...) 2004-04-02 14:10 ` steven at gcc dot gnu dot org @ 2004-05-21 19:44 ` pinskia at gcc dot gnu dot org 2004-05-24 19:18 ` pinskia at gcc dot gnu dot org ` (2 subsequent siblings) 6 siblings, 0 replies; 8+ messages in thread From: pinskia at gcc dot gnu dot org @ 2004-05-21 19:44 UTC (permalink / raw) To: gcc-bugs ------- Additional Comments From pinskia at gcc dot gnu dot org 2004-05-20 19:44 ------- Patch here: <http://gcc.gnu.org/ml/gcc-patches/2004-05/msg01275.html>. -- What |Removed |Added ---------------------------------------------------------------------------- Keywords| |patch http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14819 ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug tree-optimization/14819] [tree-ssa] strchr is not folded at tree-level 2004-04-02 6:00 [Bug optimization/14819] New: [tree-ssa] strchr is not folded at tree-level kazu at cs dot umass dot edu ` (3 preceding siblings ...) 2004-05-21 19:44 ` [Bug tree-optimization/14819] " pinskia at gcc dot gnu dot org @ 2004-05-24 19:18 ` pinskia at gcc dot gnu dot org 2004-05-31 21:01 ` cvs-commit at gcc dot gnu dot org 2004-05-31 21:04 ` kazu at cs dot umass dot edu 6 siblings, 0 replies; 8+ messages in thread From: pinskia at gcc dot gnu dot org @ 2004-05-24 19:18 UTC (permalink / raw) To: gcc-bugs ------- Additional Comments From pinskia at gcc dot gnu dot org 2004-05-24 01:22 ------- The patch was approved with the modification suggested by RTH. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14819 ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug tree-optimization/14819] [tree-ssa] strchr is not folded at tree-level 2004-04-02 6:00 [Bug optimization/14819] New: [tree-ssa] strchr is not folded at tree-level kazu at cs dot umass dot edu ` (4 preceding siblings ...) 2004-05-24 19:18 ` pinskia at gcc dot gnu dot org @ 2004-05-31 21:01 ` cvs-commit at gcc dot gnu dot org 2004-05-31 21:04 ` kazu at cs dot umass dot edu 6 siblings, 0 replies; 8+ messages in thread From: cvs-commit at gcc dot gnu dot org @ 2004-05-31 21:01 UTC (permalink / raw) To: gcc-bugs ------- Additional Comments From cvs-commit at gcc dot gnu dot org 2004-05-30 21:05 ------- Subject: Bug 14819 CVSROOT: /cvs/gcc Module name: gcc Changes by: kazu@gcc.gnu.org 2004-05-30 21:05:21 Modified files: gcc : ChangeLog builtins.c Log message: PR tree-optimization/14819 * builtins.c (fold_builtin_strchr): New. (fold_builtin_1): Handle BUILT_IN_STRCHR and BUILT_IN_STRRCHR with fold_builtin_strchr(). Patches: http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.3792&r2=2.3793 http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/builtins.c.diff?cvsroot=gcc&r1=1.327&r2=1.328 -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14819 ^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug tree-optimization/14819] [tree-ssa] strchr is not folded at tree-level 2004-04-02 6:00 [Bug optimization/14819] New: [tree-ssa] strchr is not folded at tree-level kazu at cs dot umass dot edu ` (5 preceding siblings ...) 2004-05-31 21:01 ` cvs-commit at gcc dot gnu dot org @ 2004-05-31 21:04 ` kazu at cs dot umass dot edu 6 siblings, 0 replies; 8+ messages in thread From: kazu at cs dot umass dot edu @ 2004-05-31 21:04 UTC (permalink / raw) To: gcc-bugs ------- Additional Comments From kazu at cs dot umass dot edu 2004-05-30 21:07 ------- Just checked in a patch: http://gcc.gnu.org/ml/gcc-cvs/2004-05/msg01066.html -- What |Removed |Added ---------------------------------------------------------------------------- Status|ASSIGNED |RESOLVED Resolution| |FIXED http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14819 ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2004-05-30 21:07 UTC | newest] Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2004-04-02 6:00 [Bug optimization/14819] New: [tree-ssa] strchr is not folded at tree-level kazu at cs dot umass dot edu 2004-04-02 6:03 ` [Bug optimization/14819] " pinskia at gcc dot gnu dot org 2004-04-02 6:18 ` kazu at cs dot umass dot edu 2004-04-02 14:10 ` steven at gcc dot gnu dot org 2004-05-21 19:44 ` [Bug tree-optimization/14819] " pinskia at gcc dot gnu dot org 2004-05-24 19:18 ` pinskia at gcc dot gnu dot org 2004-05-31 21:01 ` cvs-commit at gcc dot gnu dot org 2004-05-31 21:04 ` kazu at cs dot umass dot edu
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