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* [Bug target/19046] New: [4.0 Regression] MOVE_RATIO should be tweaked
@ 2004-12-16 22:21 pinskia at gcc dot gnu dot org
2004-12-16 22:23 ` [Bug target/19046] " pinskia at gcc dot gnu dot org
` (9 more replies)
0 siblings, 10 replies; 11+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-12-16 22:21 UTC (permalink / raw)
To: gcc-bugs
Take the following C++ code:
class StringMap {
const char empty_str[8];
public:
StringMap() : empty_str() {}
};
StringMap f()
{
StringMap a;
return a;
}
For 3.3.2, we produced (at -O3):
__Z1fv:
LFB6:
li r4,0
stw r4,0(r3)
stw r4,4(r3)
blr
on the mainline we get:
__Z1fv:
LFB5:
mflr r0
LCFI0:
bcl 20,31,"L00000000001$pb"
"L00000000001$pb":
stw r31,-4(r1)
LCFI1:
mflr r31
stw r0,8(r1)
LCFI2:
addis r2,r31,ha16(__ZZN9StringMapC1EvE3C.0-"L00000000001$pb")
la r9,lo16(__ZZN9StringMapC1EvE3C.0-"L00000000001$pb")(r2)
lwz r10,4(r9)
lwz r9,0(r9)
stw r10,4(r3)
lwz r0,8(r1)
lwz r31,-4(r1)
mtlr r0
stw r9,0(r3)
blr
--
Summary: [4.0 Regression] MOVE_RATIO should be tweaked
Product: gcc
Version: 4.0.0
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: normal
Priority: P2
Component: target
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: pinskia at gcc dot gnu dot org
CC: gcc-bugs at gcc dot gnu dot org
GCC target triplet: powerpc-darwin
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19046
^ permalink raw reply [flat|nested] 11+ messages in thread* [Bug target/19046] [4.0 Regression] MOVE_RATIO should be tweaked
2004-12-16 22:21 [Bug target/19046] New: [4.0 Regression] MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
@ 2004-12-16 22:23 ` pinskia at gcc dot gnu dot org
2004-12-16 22:58 ` dje at gcc dot gnu dot org
` (8 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-12-16 22:23 UTC (permalink / raw)
To: gcc-bugs
--
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|--- |4.0.0
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19046
^ permalink raw reply [flat|nested] 11+ messages in thread* [Bug target/19046] [4.0 Regression] MOVE_RATIO should be tweaked
2004-12-16 22:21 [Bug target/19046] New: [4.0 Regression] MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
2004-12-16 22:23 ` [Bug target/19046] " pinskia at gcc dot gnu dot org
@ 2004-12-16 22:58 ` dje at gcc dot gnu dot org
2004-12-16 22:58 ` dje at gcc dot gnu dot org
` (7 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: dje at gcc dot gnu dot org @ 2004-12-16 22:58 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From dje at gcc dot gnu dot org 2004-12-16 22:58 -------
I think it needs some experimentation to determine the best performance trade
off. I do not expect a value of 15 to be correct. I would guess at something
like
#define MOVE_RATIO (TARGET_STRING ? 2 : optimize_size ? 3 : 7)
as a good start.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19046
^ permalink raw reply [flat|nested] 11+ messages in thread* [Bug target/19046] [4.0 Regression] MOVE_RATIO should be tweaked
2004-12-16 22:21 [Bug target/19046] New: [4.0 Regression] MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
2004-12-16 22:23 ` [Bug target/19046] " pinskia at gcc dot gnu dot org
2004-12-16 22:58 ` dje at gcc dot gnu dot org
@ 2004-12-16 22:58 ` dje at gcc dot gnu dot org
2004-12-18 7:39 ` [Bug target/19046] [4.0 Regression] MOVE_RATIO should be tweaked on ppc pinskia at gcc dot gnu dot org
` (6 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: dje at gcc dot gnu dot org @ 2004-12-16 22:58 UTC (permalink / raw)
To: gcc-bugs
--
What |Removed |Added
----------------------------------------------------------------------------
CC| |dje at gcc dot gnu dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19046
^ permalink raw reply [flat|nested] 11+ messages in thread* [Bug target/19046] [4.0 Regression] MOVE_RATIO should be tweaked on ppc
2004-12-16 22:21 [Bug target/19046] New: [4.0 Regression] MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
` (2 preceding siblings ...)
2004-12-16 22:58 ` dje at gcc dot gnu dot org
@ 2004-12-18 7:39 ` pinskia at gcc dot gnu dot org
2004-12-22 7:25 ` pinskia at gcc dot gnu dot org
` (5 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-12-18 7:39 UTC (permalink / raw)
To: gcc-bugs
--
What |Removed |Added
----------------------------------------------------------------------------
Summary|[4.0 Regression] MOVE_RATIO |[4.0 Regression] MOVE_RATIO
|should be tweaked |should be tweaked on ppc
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19046
^ permalink raw reply [flat|nested] 11+ messages in thread* [Bug target/19046] [4.0 Regression] MOVE_RATIO should be tweaked on ppc
2004-12-16 22:21 [Bug target/19046] New: [4.0 Regression] MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
` (3 preceding siblings ...)
2004-12-18 7:39 ` [Bug target/19046] [4.0 Regression] MOVE_RATIO should be tweaked on ppc pinskia at gcc dot gnu dot org
@ 2004-12-22 7:25 ` pinskia at gcc dot gnu dot org
2004-12-29 18:01 ` dje at gcc dot gnu dot org
` (4 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-12-22 7:25 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From pinskia at gcc dot gnu dot org 2004-12-22 07:25 -------
One more thing I noticed is that this happens often in Ada, than anywhere else, even with the simpliest
source to print out something.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19046
^ permalink raw reply [flat|nested] 11+ messages in thread* [Bug target/19046] [4.0 Regression] MOVE_RATIO should be tweaked on ppc
2004-12-16 22:21 [Bug target/19046] New: [4.0 Regression] MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
` (4 preceding siblings ...)
2004-12-22 7:25 ` pinskia at gcc dot gnu dot org
@ 2004-12-29 18:01 ` dje at gcc dot gnu dot org
2005-01-06 23:03 ` pinskia at gcc dot gnu dot org
` (3 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: dje at gcc dot gnu dot org @ 2004-12-29 18:01 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From dje at gcc dot gnu dot org 2004-12-29 18:00 -------
Increasing the value of MOVE_RATIO and CLEAR_RATIO decreases SPEC
performance. The uses of the macro may be overloaded and confusing the cost
model. Or it could be harmed by register allocator and spilling. But
overall, the default values of MOVE_RATIO and CLEAR_RATIO based on movmemsi
appear to be good.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19046
^ permalink raw reply [flat|nested] 11+ messages in thread* [Bug target/19046] [4.0 Regression] MOVE_RATIO should be tweaked on ppc
2004-12-16 22:21 [Bug target/19046] New: [4.0 Regression] MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
` (5 preceding siblings ...)
2004-12-29 18:01 ` dje at gcc dot gnu dot org
@ 2005-01-06 23:03 ` pinskia at gcc dot gnu dot org
2005-01-07 12:23 ` steven at gcc dot gnu dot org
` (2 subsequent siblings)
9 siblings, 0 replies; 11+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-01-06 23:03 UTC (permalink / raw)
To: gcc-bugs
--
What |Removed |Added
----------------------------------------------------------------------------
Severity|normal |minor
Priority|P2 |P3
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19046
^ permalink raw reply [flat|nested] 11+ messages in thread* [Bug target/19046] [4.0 Regression] MOVE_RATIO should be tweaked on ppc
2004-12-16 22:21 [Bug target/19046] New: [4.0 Regression] MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
` (6 preceding siblings ...)
2005-01-06 23:03 ` pinskia at gcc dot gnu dot org
@ 2005-01-07 12:23 ` steven at gcc dot gnu dot org
2005-02-27 6:17 ` [Bug middle-end/19046] [4.0/4.1 Regression] usage of MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
2005-07-12 6:25 ` pinskia at gcc dot gnu dot org
9 siblings, 0 replies; 11+ messages in thread
From: steven at gcc dot gnu dot org @ 2005-01-07 12:23 UTC (permalink / raw)
To: gcc-bugs
--
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever Confirmed| |1
Last reconfirmed|0000-00-00 00:00:00 |2005-01-07 12:23:21
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19046
^ permalink raw reply [flat|nested] 11+ messages in thread* [Bug middle-end/19046] [4.0/4.1 Regression] usage of MOVE_RATIO should be tweaked
2004-12-16 22:21 [Bug target/19046] New: [4.0 Regression] MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
` (7 preceding siblings ...)
2005-01-07 12:23 ` steven at gcc dot gnu dot org
@ 2005-02-27 6:17 ` pinskia at gcc dot gnu dot org
2005-07-12 6:25 ` pinskia at gcc dot gnu dot org
9 siblings, 0 replies; 11+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-02-27 6:17 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From pinskia at gcc dot gnu dot org 2005-02-26 17:19 -------
Moving to 4.1 since this will take more work as just tweaking MOVE_RATIO for powerpc causes SPEC to
get worse. What should be tweaked is the usage of MOVE_RATIO instead.
--
What |Removed |Added
----------------------------------------------------------------------------
Component|target |middle-end
Summary|[4.0/4.1 Regression] |[4.0/4.1 Regression] usage
|MOVE_RATIO should be tweaked|of MOVE_RATIO should be
|on ppc |tweaked
Target Milestone|4.0.0 |4.1.0
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19046
^ permalink raw reply [flat|nested] 11+ messages in thread* [Bug middle-end/19046] [4.0/4.1 Regression] usage of MOVE_RATIO should be tweaked
2004-12-16 22:21 [Bug target/19046] New: [4.0 Regression] MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
` (8 preceding siblings ...)
2005-02-27 6:17 ` [Bug middle-end/19046] [4.0/4.1 Regression] usage of MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
@ 2005-07-12 6:25 ` pinskia at gcc dot gnu dot org
9 siblings, 0 replies; 11+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-07-12 6:25 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From pinskia at gcc dot gnu dot org 2005-07-12 06:19 -------
This was basically fixed on the mainline:
__Z1fv:
LFB5:
li r9,0
li r10,0
stw r9,0(r3)
stw r10,4(r3)
blr
By:
2005-06-01 Josh Conner <jconner@apple.com>
PR 21478
* gimplify.c (gimplify_init_constructor): Don't spill initializer
to read-only memory if it's sparse.
--
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
Resolution| |FIXED
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19046
^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2005-07-12 6:19 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed)
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2004-12-16 22:21 [Bug target/19046] New: [4.0 Regression] MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
2004-12-16 22:23 ` [Bug target/19046] " pinskia at gcc dot gnu dot org
2004-12-16 22:58 ` dje at gcc dot gnu dot org
2004-12-16 22:58 ` dje at gcc dot gnu dot org
2004-12-18 7:39 ` [Bug target/19046] [4.0 Regression] MOVE_RATIO should be tweaked on ppc pinskia at gcc dot gnu dot org
2004-12-22 7:25 ` pinskia at gcc dot gnu dot org
2004-12-29 18:01 ` dje at gcc dot gnu dot org
2005-01-06 23:03 ` pinskia at gcc dot gnu dot org
2005-01-07 12:23 ` steven at gcc dot gnu dot org
2005-02-27 6:17 ` [Bug middle-end/19046] [4.0/4.1 Regression] usage of MOVE_RATIO should be tweaked pinskia at gcc dot gnu dot org
2005-07-12 6:25 ` pinskia at gcc dot gnu dot org
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