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* [Bug target/39819] [avr] Missed optimisation when setting 4-byte values
[not found] <bug-39819-4@http.gcc.gnu.org/bugzilla/>
@ 2011-07-02 21:25 ` gjl at gcc dot gnu.org
0 siblings, 0 replies; 3+ messages in thread
From: gjl at gcc dot gnu.org @ 2011-07-02 21:25 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39819
Georg-Johann Lay <gjl at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
CC| |gjl at gcc dot gnu.org
Known to work| |4.6.1
Resolution| |WONTFIX
--- Comment #2 from Georg-Johann Lay <gjl at gcc dot gnu.org> 2011-07-02 21:23:59 UTC ---
Closed as WONTFIX.
Compiled the following code in 4.6.1, -std=c99 -mmcu=atmega88 -Os
typedef unsigned char uint8_t;
typedef unsigned long int uint32_t;
uint8_t as[4];
uint8_t bs[4];
static const uint8_t sz = 4;
void foo1(void) {
for (uint8_t i = 0; i < sz; i++) {
bs[i] = as[1];
}
}
void foo2(void) {
for (uint8_t i = 0; i < sz; i++) {
*(bs + i) = *(as + 1);
}
}
The result is:
foo1:
lds r24,as+1
sts bs,r24
sts bs+1,r24
sts bs+2,r24
sts bs+3,r24
ret
foo2:
lds r24,as+1
sts bs,r24
sts bs+1,r24
sts bs+2,r24
sts bs+3,r24
ret
So the difference has gone.
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug target/39819] [avr] Missed optimisation when setting 4-byte values
2009-04-19 21:09 [Bug c/39819] New: " david dot brown at hesbynett dot no
2009-04-19 22:26 ` [Bug target/39819] [avr] " eric dot weddington at atmel dot com
@ 2009-08-21 19:28 ` eric dot weddington at atmel dot com
1 sibling, 0 replies; 3+ messages in thread
From: eric dot weddington at atmel dot com @ 2009-08-21 19:28 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from eric dot weddington at atmel dot com 2009-08-21 19:28 -------
Confirmed on 4.3.2.
--
eric dot weddington at atmel dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Known to fail| |4.3.2
Last reconfirmed|0000-00-00 00:00:00 |2009-08-21 19:28:03
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39819
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug target/39819] [avr] Missed optimisation when setting 4-byte values
2009-04-19 21:09 [Bug c/39819] New: " david dot brown at hesbynett dot no
@ 2009-04-19 22:26 ` eric dot weddington at atmel dot com
2009-08-21 19:28 ` eric dot weddington at atmel dot com
1 sibling, 0 replies; 3+ messages in thread
From: eric dot weddington at atmel dot com @ 2009-04-19 22:26 UTC (permalink / raw)
To: gcc-bugs
--
eric dot weddington at atmel dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |eric dot weddington at atmel
| |dot com
Severity|enhancement |normal
Component|c |target
GCC host triplet|mingw |
GCC target triplet|avr-gcc |avr-*-*
Keywords| |missed-optimization
Summary|Missed optimisation when |[avr] Missed optimisation
|setting 4-byte values |when setting 4-byte values
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39819
^ permalink raw reply [flat|nested] 3+ messages in thread
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[not found] <bug-39819-4@http.gcc.gnu.org/bugzilla/>
2011-07-02 21:25 ` [Bug target/39819] [avr] Missed optimisation when setting 4-byte values gjl at gcc dot gnu.org
2009-04-19 21:09 [Bug c/39819] New: " david dot brown at hesbynett dot no
2009-04-19 22:26 ` [Bug target/39819] [avr] " eric dot weddington at atmel dot com
2009-08-21 19:28 ` eric dot weddington at atmel dot com
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