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* [Bug middle-end/21417] New: Missed jump threading opportunity on trees
@ 2005-05-06 13:11 steven at gcc dot gnu dot org
2005-05-06 13:52 ` [Bug middle-end/21417] " kazu at cs dot umass dot edu
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: steven at gcc dot gnu dot org @ 2005-05-06 13:11 UTC (permalink / raw)
To: gcc-bugs
Consider the following test case (t.c):
--------------------------------
struct tree_common
{
int code;
};
union tree_node
{
struct tree_common common;
};
typedef union tree_node *tree;
extern tree test (tree, int, int);
extern tree foo (void);
extern void abort (void) __attribute__ ((__noreturn__));
tree
test (tree expr, int t, int D17630)
{
int __i;
L0:
if (expr->common.code != 142) goto L23; else goto L2;
L2:
__i = 0;
goto L10;
L10:
__i = __i + 1;
if (D17630 != __i) goto L8; else goto L19;
L8:
if (t) goto L15; else goto L10;
L15:
expr = foo ();
if (expr->common.code != 142) goto L23; else goto L0;
L19:
abort ();
L23:
return expr;
}
--------------------------------
$ ./cc1 -quiet -O3 -dG --param max-cse-path-length=1 -fdump-tree-vars t.c
$ grep "Bypass edge" t.c.07.bypass
Bypass edge from 5->1 to 2
# ./cc1 --version
GNU C version 4.1.0 20050506 (experimental) (x86_64-unknown-linux-gnu)
compiled by GNU C version 4.1.0 20050506 (experimental).
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
--
Summary: Missed jump threading opportunity on trees
Product: gcc
Version: 4.1.0
Status: UNCONFIRMED
Keywords: missed-optimization, TREE
Severity: normal
Priority: P2
Component: middle-end
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: steven at gcc dot gnu dot org
CC: gcc-bugs at gcc dot gnu dot org,law at redhat dot com
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21417
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug middle-end/21417] Missed jump threading opportunity on trees
2005-05-06 13:11 [Bug middle-end/21417] New: Missed jump threading opportunity on trees steven at gcc dot gnu dot org
@ 2005-05-06 13:52 ` kazu at cs dot umass dot edu
2005-05-06 13:53 ` [Bug tree-optimization/21417] " pinskia at gcc dot gnu dot org
2005-05-06 14:12 ` pinskia at gcc dot gnu dot org
2 siblings, 0 replies; 4+ messages in thread
From: kazu at cs dot umass dot edu @ 2005-05-06 13:52 UTC (permalink / raw)
To: gcc-bugs
--
What |Removed |Added
----------------------------------------------------------------------------
CC| |kazu at cs dot umass dot edu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21417
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug tree-optimization/21417] Missed jump threading opportunity on trees
2005-05-06 13:11 [Bug middle-end/21417] New: Missed jump threading opportunity on trees steven at gcc dot gnu dot org
2005-05-06 13:52 ` [Bug middle-end/21417] " kazu at cs dot umass dot edu
@ 2005-05-06 13:53 ` pinskia at gcc dot gnu dot org
2005-05-06 14:12 ` pinskia at gcc dot gnu dot org
2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-05-06 13:53 UTC (permalink / raw)
To: gcc-bugs
--
What |Removed |Added
----------------------------------------------------------------------------
Component|middle-end |tree-optimization
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21417
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug tree-optimization/21417] Missed jump threading opportunity on trees
2005-05-06 13:11 [Bug middle-end/21417] New: Missed jump threading opportunity on trees steven at gcc dot gnu dot org
2005-05-06 13:52 ` [Bug middle-end/21417] " kazu at cs dot umass dot edu
2005-05-06 13:53 ` [Bug tree-optimization/21417] " pinskia at gcc dot gnu dot org
@ 2005-05-06 14:12 ` pinskia at gcc dot gnu dot org
2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-05-06 14:12 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From pinskia at gcc dot gnu dot org 2005-05-06 14:12 -------
Confirmed, there is a load PRE missing also which looks like is causing the jump threader not to be able
to do this jump.
--
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever Confirmed| |1
Last reconfirmed|0000-00-00 00:00:00 |2005-05-06 14:12:07
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21417
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2005-05-06 14:12 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2005-05-06 13:11 [Bug middle-end/21417] New: Missed jump threading opportunity on trees steven at gcc dot gnu dot org
2005-05-06 13:52 ` [Bug middle-end/21417] " kazu at cs dot umass dot edu
2005-05-06 13:53 ` [Bug tree-optimization/21417] " pinskia at gcc dot gnu dot org
2005-05-06 14:12 ` pinskia at gcc dot gnu dot org
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