[Bug target/56833] New: [4.9 Regression] Valid register is over written by reload pass

[Bug target/56833] New: [4.9 Regression] Valid register is over written by reload pass

[vishnu.k_s at atmel dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56833

             Bug #: 56833
           Summary: [4.9 Regression] Valid register is over written by
                    reload pass
    Classification: Unclassified
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: vishnu.k_s@atmel.com


AVR target built with specs:

Using built-in specs.
COLLECT_GCC=/home/vishnu.k_s/build-linux_x86_64/bldcc/gcc/xgcc
Target: avr
Configured with: ../gcc-trunk/configure
--prefix=/home/vishnu.k_s/build-linux_x86_64//install --target=avr
--enable-languages=c,c++ --disable-nls --with-gmp=/proj/install/gmp-4.3.2/
--with-mpfr=/proj/install/mpfr-2.4.2/ --with-mpc=/proj/install/mpc-0.8.2/
Thread model: single
gcc version 4.9.0 20130326 (experimental) (GCC)

Above compiler generate wrong code for testcase present in
gcc.c-torture/execute/simd-1.c.
gcc options : -O1 -mmcu=atmega1280

(snip of assembly)

ldi r30,lo8(res)    ; r30/r31 is loaded with address of res
ldi r31,hi8(res)    ;
st Z,r24   

ldd r31,Y+1         ;    Modifying r31 register

sts res+1,r31
sts res+2,r27
sts res+3,r26
sts res+4,r23
...
lds r22,res+4+2
lds r23,res+4+3

ld r24,Z             ; regsiter pair r30/r31 is used to load from res
ldd r25,Z+1
ldd r26,Z+2
ldd r27,Z+3

(snip of assembly)

It looks like r31 is corrupted after reload pass.

[Bug other/56833] [4.9 Regression] Valid register is over written by reload pass

[vishnu.k_s at atmel dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56833

vishnu ks <vishnu.k_s at atmel dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|target                      |other

--- Comment #1 from vishnu ks <vishnu.k_s at atmel dot com> 2013-04-03 12:50:55 UTC ---
This bug might be similar to PR56442, which is not reproducible in 4.9.
conversation in mailing list : http://gcc.gnu.org/ml/gcc/2013-03/msg00121.html

[Bug target/56833] [4.9 Regression] Valid register is over written by reload pass

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56833

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code
          Component|other                       |target
   Target Milestone|---                         |4.9.0

[Bug rtl-optimization/56833] [4.9 Regression] Valid register is over written by reload pass

[amylaar at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56833

Jorn Wolfgang Rennecke <amylaar at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |amylaar at gcc dot gnu.org
          Component|target                      |rtl-optimization

--- Comment #2 from Jorn Wolfgang Rennecke <amylaar at gcc dot gnu.org> ---
It's a postreload bug.

[Bug rtl-optimization/56833] [4.9 Regression] Valid register is over written by postreload pass

[steven at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56833

Steven Bosscher <steven at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-05-15
            Summary|[4.9 Regression] Valid      |[4.9 Regression] Valid
                   |register is over written by |register is over written by
                   |reload pass                 |postreload pass
     Ever confirmed|0                           |1

[Bug rtl-optimization/56833] [4.9 Regression] Valid register is over written by postreload pass

[amylaar at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56833

Jorn Wolfgang Rennecke <amylaar at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |patch

--- Comment #3 from Jorn Wolfgang Rennecke <amylaar at gcc dot gnu.org> ---
The patch has been posted:
http://gcc.gnu.org/ml/gcc-patches/2013-05/msg00845.html

[Bug rtl-optimization/56833] [4.9 Regression] Valid register is over written by postreload pass

[amylaar at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56833

Jorn Wolfgang Rennecke <amylaar at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

--- Comment #4 from Jorn Wolfgang Rennecke <amylaar at gcc dot gnu.org> ---
http://gcc.gnu.org/ml/gcc-cvs/2013-05/msg00874.html
        PR rtl-optimization/56833
        * postreload.c (move2add_record_mode): New function.
        (move2add_record_sym_value, move2add_valid_value_p): Likewise.
        (move2add_use_add2_insn): Use move2add_record_sym_value.
        (move2add_use_add3_insn): Likewise.
        (reload_cse_move2add): Use move2add_valid_value_p and
        move2add_record_mode.  Invalidate call-clobbered and REG_INC
        affected regs by setting reg_mode to VOIDmode.
        (move2add_note_store): Don't pretend the inside of a SUBREG is
        the actual destination.  Invalidate single/leading registers by
        setting reg_mode to VOIDmode.
        Use move2add_record_sym_value, move2add_valid_value_p and
        move2add_record_mode.

[Bug rtl-optimization/56833] [4.9 Regression] Valid register is over written by postreload pass

[gjl at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56833

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

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

--- Comment #5 from Georg-Johann Lay <gjl at gcc dot gnu.org> ---
This PR looks similar to PR56442 for the 4.8 branch.  Does your patch fix that
problem, too?

[Bug rtl-optimization/56833] [4.9 Regression] Valid register is over written by postreload pass

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56833

Bug 56833 depends on bug 57439, which changed state.

Bug 57439 Summary: [4.9 regression] FAIL: gcc.c-torture/execute/920501-6.c execution,  -O1
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57439

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

[Bug rtl-optimization/56833] [4.9 Regression] Valid register is over written by postreload pass

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56833

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |hjl.tools at gmail dot com

--- Comment #6 from H.J. Lu <hjl.tools at gmail dot com> ---
*** Bug 50891 has been marked as a duplicate of this bug. ***