[Bug target/36424] New: avr-gcc use don't saved registers in ISR with -O3 ('-frename-registers' ) optimization

[Bug target/36424] New: avr-gcc use don't saved registers in ISR with -O3 ('-frename-registers' ) optimization

[aesok at gcc dot gnu dot org]

Testcase:
#include <avr/io.h>
#include <avr/interrupt.h>

volatile unsigned char   UART_RxChar;
volatile unsigned char   UART_ReceivedChar;

SIGNAL(SIG_USART_RECV)      
{
    /* Indicate that the UART has received a character */
    UART_ReceivedChar = 1;
    /* Store received character */
    UART_RxChar = UDR;
}

Request: use -frename-registers optimization, enabled on -O3.

Result code:
.global __vector_13
 .type __vector_13, @function
__vector_13:
.LFB2:
.LM1:
 push __zero_reg__
 push r0
 in r0,__SREG__
 push r0
 clr __zero_reg__
 push r24
/* prologue: Signal */
/* frame size = 0 */
.LM2:
 ldi r26,lo8(1)
 sts UART_ReceivedChar,r26
.LM3:
 lds r24,198
 sts UART_RxChar,r24
/* epilogue start */
.LM4:
 pop r24
 pop r0
 out __SREG__,r0
 pop r0
 pop __zero_reg__
 reti

R26 register used in ISR but don't saved/restored.

To fix bug, need define HARD_REGNO_RENAME_OK macro in config/avr.h

Anatoly.


-- 
           Summary: avr-gcc use don't saved registers in ISR with -O3 ('-
                    frename-registers' ) optimization
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: aesok at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36424

[Bug target/36424] avr-gcc use don't saved registers in ISR with -O3 ('-frename-registers' ) optimization

[aesok at gcc dot gnu dot org]

------- Comment #1 from aesok at gcc dot gnu dot org  2008-06-02 18:06 -------
Created an attachment (id=15713)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=15713&action=view)
The patch for 36424


-- 

aesok at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |aesok at gcc dot gnu dot org
                   |dot org                     |
             Status|UNCONFIRMED                 |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36424

[Bug target/36424] avr-gcc use don't saved registers in ISR with -O3 ('-frename-registers' ) optimization

[eric dot weddington at atmel dot com]

------- Comment #2 from eric dot weddington at atmel dot com  2008-06-04 22:55 -------
*** Bug 36423 has been marked as a duplicate of this bug. ***


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36424

[Bug target/36424] avr-gcc use don't saved registers in ISR with -O3 ('-frename-registers' ) optimization

[aesok at gcc dot gnu dot org]

------- Comment #3 from aesok at gcc dot gnu dot org  2008-06-08 16:08 -------
Subject: Bug 36424

Author: aesok
Date: Sun Jun  8 16:08:08 2008
New Revision: 136562

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=136562
Log:
        PR target/36424
        * config/avr/avr.h (HARD_REGNO_RENAME_OK): Define.
        * config/avr/avr.c (avr_hard_regno_rename_ok): New function. 
        * config/avr/avr-protos.h (avr_hard_regno_rename_ok): New prototype. 

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/avr/avr-protos.h
    trunk/gcc/config/avr/avr.c
    trunk/gcc/config/avr/avr.h


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36424

[Bug target/36424] avr-gcc use don't saved registers in ISR with -O3 ('-frename-registers' ) optimization

[eric dot weddington at atmel dot com]

------- Comment #4 from eric dot weddington at atmel dot com  2008-06-08 17:32 -------
Fixed for 4.4.0.


-- 

eric dot weddington at atmel dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36424

[Bug target/36424] avr-gcc use don't saved registers in ISR with -O3 ('-frename-registers' ) optimization

[aesok at gcc dot gnu dot org]

------- Comment #5 from aesok at gcc dot gnu dot org  2008-06-15 21:33 -------
Subject: Bug 36424

Author: aesok
Date: Sun Jun 15 21:32:29 2008
New Revision: 136826

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=136826
Log:
        PR target/36424
        * config/avr/avr.h (HARD_REGNO_RENAME_OK): Define.
        * config/avr/avr.c (avr_hard_regno_rename_ok): New function. 
        * config/avr/avr-protos.h (avr_hard_regno_rename_ok): New prototype. 

Modified:
    branches/gcc-4_3-branch/gcc/ChangeLog
    branches/gcc-4_3-branch/gcc/config/avr/avr-protos.h
    branches/gcc-4_3-branch/gcc/config/avr/avr.c
    branches/gcc-4_3-branch/gcc/config/avr/avr.h


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36424

[Bug target/36424] avr-gcc use don't saved registers in ISR with -O3 ('-frename-registers' ) optimization

[aesok at gcc dot gnu dot org]

------- Comment #6 from aesok at gcc dot gnu dot org  2008-06-15 21:36 -------
Fixed for 4.3.2.


-- 

aesok at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.4.0                       |4.3.2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36424