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* [Bug target/20296] Speeding up small interrupts on avr
       [not found] <bug-20296-4@http.gcc.gnu.org/bugzilla/>
@ 2011-11-06 20:40 ` wiml at hhhh dot org
  2012-03-03 14:21 ` gjl at gcc dot gnu.org
  2012-03-03 16:34 ` gjl at gcc dot gnu.org
  2 siblings, 0 replies; 6+ messages in thread
From: wiml at hhhh dot org @ 2011-11-06 20:40 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20296

Wim Lewis <wiml at hhhh dot org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |wiml at hhhh dot org

--- Comment #2 from Wim Lewis <wiml at hhhh dot org> 2011-11-06 20:39:49 UTC ---
FWIW, confirming that versions 4.3.4 and 4.6.2 still emit these unnecessary
saves of r0 and r1 for small ISRs (the generated code is identical to what
berndtrog@yahoo.com posted, at least for optimization levels >= 1).


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/20296] Speeding up small interrupts on avr
       [not found] <bug-20296-4@http.gcc.gnu.org/bugzilla/>
  2011-11-06 20:40 ` [Bug target/20296] Speeding up small interrupts on avr wiml at hhhh dot org
@ 2012-03-03 14:21 ` gjl at gcc dot gnu.org
  2012-03-03 16:34 ` gjl at gcc dot gnu.org
  2 siblings, 0 replies; 6+ messages in thread
From: gjl at gcc dot gnu.org @ 2012-03-03 14:21 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20296

Georg-Johann Lay <gjl at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P2                          |P5
                 CC|                            |gjl at gcc dot gnu.org


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/20296] Speeding up small interrupts on avr
       [not found] <bug-20296-4@http.gcc.gnu.org/bugzilla/>
  2011-11-06 20:40 ` [Bug target/20296] Speeding up small interrupts on avr wiml at hhhh dot org
  2012-03-03 14:21 ` gjl at gcc dot gnu.org
@ 2012-03-03 16:34 ` gjl at gcc dot gnu.org
  2 siblings, 0 replies; 6+ messages in thread
From: gjl at gcc dot gnu.org @ 2012-03-03 16:34 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20296

Georg-Johann Lay <gjl at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |SUSPENDED


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/20296] Speeding up small interrupts on avr
  2005-03-02 23:47 [Bug target/20296] New: " berndtrog at yahoo dot com
  2005-03-04 19:51 ` [Bug target/20296] " bjoern dot m dot haase at web dot de
  2005-03-04 23:47 ` ericw at evcohs dot com
@ 2005-03-05  1:10 ` giovannibajo at libero dot it
  2 siblings, 0 replies; 6+ messages in thread
From: giovannibajo at libero dot it @ 2005-03-05  1:10 UTC (permalink / raw)
  To: gcc-bugs



-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2005-03-05 01:10:40
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20296


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/20296] Speeding up small interrupts on avr
  2005-03-02 23:47 [Bug target/20296] New: " berndtrog at yahoo dot com
  2005-03-04 19:51 ` [Bug target/20296] " bjoern dot m dot haase at web dot de
@ 2005-03-04 23:47 ` ericw at evcohs dot com
  2005-03-05  1:10 ` giovannibajo at libero dot it
  2 siblings, 0 replies; 6+ messages in thread
From: ericw at evcohs dot com @ 2005-03-04 23:47 UTC (permalink / raw)
  To: gcc-bugs



-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ericw at evcohs dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20296


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [Bug target/20296] Speeding up small interrupts on avr
  2005-03-02 23:47 [Bug target/20296] New: " berndtrog at yahoo dot com
@ 2005-03-04 19:51 ` bjoern dot m dot haase at web dot de
  2005-03-04 23:47 ` ericw at evcohs dot com
  2005-03-05  1:10 ` giovannibajo at libero dot it
  2 siblings, 0 replies; 6+ messages in thread
From: bjoern dot m dot haase at web dot de @ 2005-03-04 19:51 UTC (permalink / raw)
  To: gcc-bugs

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------- Additional Comments From bjoern dot m dot haase at web dot de  2005-03-04 19:51 -------
Hi, 
 
IMHO everyone working on the avr back-end is aware of this problem. The 
difficulty is, that the present architecture of the avr back-end does not 
easily permit to improve this case: Every instruction pattern (like "multiply 
two 16 bit integers" or "sign-extend a 16 bit variable to 32 bits") presently 
is free to assume that may overwrite or change r0 and r1 unless it leaves the 
"__zero_reg__" with 0 after finishing it's task. 
 
Resolving this issue, IMHO, would require a major refactoring of the 
back-end. ... IIUC the keyword is "replace all of the more complex instruction 
patterns by RTL expressions." 
 
I suggest to mark this bug as "desired enhancement". 
 
Yours, 
 
Björn 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20296


^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2012-03-03 16:34 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
     [not found] <bug-20296-4@http.gcc.gnu.org/bugzilla/>
2011-11-06 20:40 ` [Bug target/20296] Speeding up small interrupts on avr wiml at hhhh dot org
2012-03-03 14:21 ` gjl at gcc dot gnu.org
2012-03-03 16:34 ` gjl at gcc dot gnu.org
2005-03-02 23:47 [Bug target/20296] New: " berndtrog at yahoo dot com
2005-03-04 19:51 ` [Bug target/20296] " bjoern dot m dot haase at web dot de
2005-03-04 23:47 ` ericw at evcohs dot com
2005-03-05  1:10 ` giovannibajo at libero dot it

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