[Bug target/59710] New: Nios2: Missing gprel optimization

[Bug target/59710] New: Nios2: Missing gprel optimization

[sebastian.huber@embedded-brains.de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59710

            Bug ID: 59710
           Summary: Nios2: Missing gprel optimization
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: sebastian.huber@embedded-brains.de

The compiler doesn't generate gprel load/store operations for variables
external to the translation unit (this is unlike the PowerPC target for
example).  Consider the following test case:

gprel-ok.c:

int iii;
int jjj = 456;

void gprel_ok(void)
{
        iii = 123;
        jjj = 789;
}

gprel-not-ok.c:

extern int iii;
extern int jjj;

void gprel_not_ok(void)
{
        iii = 123;
        jjj = 789;
}

nios2-elf-gcc -O2 -fno-common -S gprel-ok.c
nios2-elf-gcc -O2 -fno-common -S gprel-not-ok.c

gprel-ok.s:

        .file   "gprel-ok.c"
        .section        .text
        .align  2
        .global gprel_ok
        .type   gprel_ok, @function
gprel_ok:
        movi    r2, 123
        stw     r2, %gprel(iii)(gp)
        movi    r2, 789
        stw     r2, %gprel(jjj)(gp)
        ret
        .size   gprel_ok, .-gprel_ok
        .global jjj
        .section        .sdata,"aws",@progbits
        .align  2
        .type   jjj, @object
        .size   jjj, 4
jjj:
        .long   456
        .global iii
        .section        .sbss,"aws",@nobits
        .align  2
        .type   iii, @object
        .size   iii, 4
iii:
        .zero   4
        .ident  "GCC: (GNU) 4.9.0 20140103 (experimental)"

gprel-not-ok.s:

        .file   "gprel-not-ok.c"
        .section        .text
        .align  2
        .global gprel_not_ok
        .type   gprel_not_ok, @function
gprel_not_ok:
        movi    r3, 123
        movhi   r2, %hiadj(iii)
        addi    r2, r2, %lo(iii)
        stw     r3, 0(r2)
        movi    r3, 789
        movhi   r2, %hiadj(jjj)
        addi    r2, r2, %lo(jjj)
        stw     r3, 0(r2)
        ret
        .size   gprel_not_ok, .-gprel_not_ok
        .ident  "GCC: (GNU) 4.9.0 20140103 (experimental)"

[Bug target/59710] Nios2: Missing gprel optimization

[sandra at codesourcery dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59710

Sandra Loosemore <sandra at codesourcery dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |sandra at codesourcery dot com

--- Comment #1 from Sandra Loosemore <sandra at codesourcery dot com> ---
I'm working on a patch that will fix this by adding some additional choices for
-mgpopt.

[Bug target/59710] Nios2: Missing gprel optimization

[sandra at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59710

--- Comment #2 from sandra at gcc dot gnu.org ---
Author: sandra
Date: Fri Jan 16 00:43:24 2015
New Revision: 219700

URL: https://gcc.gnu.org/viewcvs?rev=219700&root=gcc&view=rev
Log:
2015-01-15  Sandra Loosemore  <sandra@codesourcery.com>

    PR target/59710

    gcc/
    * doc/invoke.texi (Option Summary): Document new Nios II
    -mgpopt= syntax.
    (Nios II Options): Likewise.
    * config/nios2/nios2.opt: Add -mgpopt= option support.
    Modify existing -mgpopt and -mno-gpopt options to be aliases.
    * config/nios2/nios2-opts.h (enum nios2_gpopt_type): New.
    * config/nios2/nios2.c (nios2_option_override): Adjust
    -mgpopt defaulting.
    (nios2_in_small_data_p): Return true for explicit small data
    sections even with -G0.
    (nios2_symbol_ref_in_small_data_p): Adjust to handle new -mgpopt=
    option choices.

    gcc/testsuite/
    * gcc.target/nios2/gpopt-all.c: New test case.
    * gcc.target/nios2/gpopt-local.c: New test case.
    * gcc.target/nios2/gpopt-global.c: New test case.
    * gcc.target/nios2/gpopt-data.c: New test case.
    * gcc.target/nios2/gpopt-none.c: New test case.

Added:
    trunk/gcc/testsuite/gcc.target/nios2/gpopt-all.c
    trunk/gcc/testsuite/gcc.target/nios2/gpopt-data.c
    trunk/gcc/testsuite/gcc.target/nios2/gpopt-global.c
    trunk/gcc/testsuite/gcc.target/nios2/gpopt-local.c
    trunk/gcc/testsuite/gcc.target/nios2/gpopt-none.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/nios2/nios2-opts.h
    trunk/gcc/config/nios2/nios2.c
    trunk/gcc/config/nios2/nios2.opt
    trunk/gcc/doc/invoke.texi
    trunk/gcc/testsuite/ChangeLog

[Bug target/59710] Nios2: Missing gprel optimization

[sebastian.huber@embedded-brains.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59710

Sebastian Huber <sebastian.huber@embedded-brains.de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|                            |5.0

--- Comment #3 from Sebastian Huber <sebastian.huber@embedded-brains.de> ---
Thanks, this fixes the problem in case the new -mgpot=global option is used. Do
you plan to back port this to GCC 4.9? If not, then can you please adjust the
target milestone and close the PR.

nios2-elf-gcc -O2 -mgpopt=global -fno-common -S gprel-ok.c && cat gprel-ok.s
        .file   "gprel-ok.c"
        .section        .text
        .align  2
        .global gprel_ok
        .type   gprel_ok, @function
gprel_ok:
        movi    r2, 123
        stw     r2, %gprel(iii)(gp)
        movi    r2, 789
        stw     r2, %gprel(jjj)(gp)
        ret
        .size   gprel_ok, .-gprel_ok
        .global jjj
        .section        .sdata,"aws",@progbits
        .align  2
        .type   jjj, @object
        .size   jjj, 4
jjj:
        .long   456
        .global iii
        .section        .sbss,"aws",@nobits
        .align  2
        .type   iii, @object
        .size   iii, 4
iii:
        .zero   4
        .ident  "GCC: (GNU) 5.0.0 20150116 (experimental)"
nios2-elf-gcc -O2 -mgpopt=global -fno-common -S gprel-not-ok.c && cat
gprel-not-ok.s
        .file   "gprel-not-ok.c"
        .section        .text
        .align  2
        .global gprel_not_ok
        .type   gprel_not_ok, @function
gprel_not_ok:
        movi    r2, 123
        stw     r2, %gprel(iii)(gp)
        movi    r2, 789
        stw     r2, %gprel(jjj)(gp)
        ret
        .size   gprel_not_ok, .-gprel_not_ok
        .ident  "GCC: (GNU) 5.0.0 20150116 (experimental)"

[Bug target/59710] Nios2: Missing gprel optimization

[sandra at codesourcery dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59710

--- Comment #4 from Sandra Loosemore <sandra at codesourcery dot com> ---
I'm thinking this isn't an appropriate kind of patch to backport to 4.9 -- it's
a fix for a missed optimization and not a serious bug (wrong code or ICE).

Maybe I'm being exceptionally dense here, but I can't figure out how to close
an issue or adjust milestones in bugzilla -- all I get when I click on "Status"
is a page with an explanation of what the different statuses mean.  Maybe I
lack appropriate admin powers to do that?

[Bug target/59710] Nios2: Missing gprel optimization

[joseph at codesourcery dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59710

--- Comment #5 from joseph at codesourcery dot com <joseph at codesourcery dot com> ---
You need to use Bugzilla with your @gcc.gnu.org address to have rights to 
modify bugs.  @gcc.gnu.org accounts should have such rights automatically, 
though overseers should be able to grant them to other accounts.

[Bug target/59710] Nios2: Missing gprel optimization

[sandra at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59710

sandra at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
                 CC|                            |sandra at gcc dot gnu.org
         Resolution|---                         |FIXED
   Target Milestone|---                         |5.0

--- Comment #6 from sandra at gcc dot gnu.org ---
Aha, the magic buttons appear!  Thanks, Joseph.