[Bug middle-end/40718] New: Invalid code produced with -foptimize-sibling-calls

[Bug middle-end/40718] New: Invalid code produced with -foptimize-sibling-calls

[d dot g dot gorbachev at gmail dot com]

The following program will fail.

gcc -S -O1 -foptimize-sibling-calls bug.c

bug.c:
============================================
#define stdcall __attribute__((__stdcall__))

struct S {
    void (stdcall *f)(struct S *);
    int i;
};

void stdcall foo(struct S *s)
{
    s->i++;
}

void stdcall bar(struct S *s)
{
    foo(s);
    s->f(s);
}

int main(void)
{
    struct S s = { foo, 0 };
    bar(&s);
}
============================================

This is what the compiler produces:

bar:
        pushl   %ebp
        movl    %esp, %ebp
        pushl   %ebx
        subl    $20, %esp
        movl    8(%ebp), %ebx
        movl    %ebx, (%esp)
        call    foo
        subl    $4, %esp
        movl    %ebx, 8(%ebp)
        movl    -4(%ebp), %ebx
        leave
        jmp     *(%ebx)


-- 
           Summary: Invalid code produced with -foptimize-sibling-calls
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: d dot g dot gorbachev at gmail dot com
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug middle-end/40718] Invalid code produced with -foptimize-sibling-calls

[slyfox at inbox dot ru]

------- Comment #1 from slyfox at inbox dot ru  2009-08-22 12:09 -------
I can confirm gcc-4.4.1 errors the same way.

I think stdcall is offender:
My sample is more complicated, but has the same features: stdcall+tailcall.

Produces SIGSEGV for me https://bugs.gentoo.org/show_bug.cgi?id=282189


-- 

slyfox at inbox dot ru changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |slyfox at inbox dot ru


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[ubizjak at gmail dot com]

------- Comment #2 from ubizjak at gmail dot com  2009-08-22 13:38 -------
Have a patch.


-- 

ubizjak at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |ubizjak at gmail dot com
                   |dot org                     |
             Status|UNCONFIRMED                 |ASSIGNED
          Component|middle-end                  |target
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2009-08-22 13:38:01
               date|                            |
   Target Milestone|---                         |4.3.5


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[ubizjak at gmail dot com]

------- Comment #3 from ubizjak at gmail dot com  2009-08-22 13:43 -------
Created an attachment (id=18413)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=18413&action=view)
patch to fix the failure

Sibcalls of any kind should be done through call-clobbered regs only.

This patch fixes the testcase.

Sergei, can you please test it if it fixes your original problem?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[ubizjak at gmail dot com]

------- Comment #4 from ubizjak at gmail dot com  2009-08-22 13:51 -------
Patched gcc:

bar:
        pushl   %ebp
        movl    %esp, %ebp
        pushl   %ebx
        subl    $20, %esp
        movl    8(%ebp), %ebx
        movl    %ebx, (%esp)
        call    foo
        subl    $4, %esp
        movl    %ebx, 8(%ebp)
        movl    (%ebx), %eax
        movl    -4(%ebp), %ebx
        leave
        jmp     *%eax


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[slyfox at inbox dot ru]

------- Comment #5 from slyfox at inbox dot ru  2009-08-22 18:38 -------
(In reply to comment #3)
> Created an attachment (id=18413)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=18413&action=view) [edit]
> patch to fix the failure
> 
> Sibcalls of any kind should be done through call-clobbered regs only.
> 
> This patch fixes the testcase.
> 
> Sergei, can you please test it if it fixes your original problem?
> 

Sorry, it does not compile on gcc-4.4.1:

build/genoutput
/tmp/paludis/sys-devel-gcc-4.4.1-r1/work/gcc-4.4.1/gcc/config/i386/i386.md \
          insn-conditions.md > tmp-output.c
/tmp/paludis/sys-devel-gcc-4.4.1-r1/work/gcc-4.4.1/gcc/config/i386/i386.md:14984:
wrong number of alternatives in operand 2
make[3]: *** [s-output] Error 1
make[3]: *** Waiting for unfinished jobs....


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[ubizjak at gmail dot com]

------- Comment #6 from ubizjak at gmail dot com  2009-08-23 09:08 -------
Created an attachment (id=18415)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=18415&action=view)
Updated patch

This patch is bootstrapped and regression tested.


-- 

ubizjak at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #18413|0                           |1
        is obsolete|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[uros at gcc dot gnu dot org]

------- Comment #7 from uros at gcc dot gnu dot org  2009-08-23 09:46 -------
Subject: Bug 40718

Author: uros
Date: Sun Aug 23 09:46:00 2009
New Revision: 151028

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=151028
Log:
        PR target/40718
        * config/i386/i386.c (*call_pop_1): Disable for sibling calls.
        (*sibcall_pop_1): New insn pattern.

testsuite/ChangeLog:

        PR target/40718
        * gcc.target/i386/pr40718.c: New test.


Added:
    trunk/gcc/testsuite/gcc.target/i386/pr40718.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/i386/i386.md
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[slyfox at inbox dot ru]

------- Comment #8 from slyfox at inbox dot ru  2009-08-23 11:12 -------
(In reply to comment #7)
> Subject: Bug 40718
> 
> Author: uros
> Date: Sun Aug 23 09:46:00 2009
> New Revision: 151028
> 
> URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=151028
> Log:
>         PR target/40718
>         * config/i386/i386.c (*call_pop_1): Disable for sibling calls.
>         (*sibcall_pop_1): New insn pattern.
> 
> testsuite/ChangeLog:
> 
>         PR target/40718
>         * gcc.target/i386/pr40718.c: New test.
> 
> 
> Added:
>     trunk/gcc/testsuite/gcc.target/i386/pr40718.c
> Modified:
>     trunk/gcc/ChangeLog
>     trunk/gcc/config/i386/i386.md
>     trunk/gcc/testsuite/ChangeLog
> 

This patch fixes for me Dmitry's sample, but does not fix mine. Still SIGSEGVs.
I've managed to
place whole testcase in one file:

$ g++ -O1 -foptimize-sibling-calls -m32 -DCALLTYPE="__attribute__((stdcall))"
main.cc -o show_the_bug 
$ ./show_the_bug
Segmentation fault
$ cat main.cc 
#define CALLTYPE __attribute__((stdcall))

struct Base {
    virtual unsigned long CALLTYPE base_do1(unsigned long, unsigned long)
__attribute__((noinline))
    {
        return 4;
    }
};

static Base bi;
Base * glo_ptr_to_base = &bi;

struct Stuff {
    void CALLTYPE do_stuff(unsigned long param1, unsigned long param2)
__attribute__((noinline))
    {
        if (param1 == 0xFFFFFFFE)
        {
            return;
        }
        glo_ptr_to_base->base_do1(param1, param2);
    }
};

int
main()
{
    Stuff o;
    o.do_stuff(1, 32);
    return 0;
}

-----------------------------------------------
_ZN5Stuff8do_stuffEmm:
.LFB1:
        .cfi_startproc
        .cfi_personality 0x0,__gxx_personality_v0
        pushl   %ebp
        .cfi_def_cfa_offset 8
        movl    %esp, %ebp
        .cfi_offset 5, -8
        .cfi_def_cfa_register 5
        pushl   %ebx
        subl    $4, %esp
        movl    12(%ebp), %eax
        cmpl    $-2, %eax
        je      .L5
        .cfi_offset 3, -12
        movl    glo_ptr_to_base, %edx
        movl    %edx, 8(%ebp)
        movl    -4(%ebp), %ebx
        leave
        jmp     *(%ebx)
.L5:
        movl    -4(%ebp), %ebx
        leave
        ret     $12
        .cfi_endproc


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[ubizjak at gmail dot com]

------- Comment #9 from ubizjak at gmail dot com  2009-08-23 11:41 -------
(In reply to comment #8)

> This patch fixes for me Dmitry's sample, but does not fix mine. Still SIGSEGVs.
> I've managed to
> place whole testcase in one file:

Ah, the same cure should be applied to "*call_value_pop_1" pattern too.

Wait a minute, I'll craft a patch ASAP.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[ubizjak at gmail dot com]

------- Comment #10 from ubizjak at gmail dot com  2009-08-23 11:57 -------
Created an attachment (id=18416)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=18416&action=view)
Additional patch

Additional patch to fix call_value_pop_1.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[ubizjak at gmail dot com]

------- Comment #11 from ubizjak at gmail dot com  2009-08-23 12:08 -------
Patched gcc compiles testcase from comment 8 to:

_ZN5Stuff8do_stuffEmm:
.LFB4:
        .cfi_startproc
        .cfi_personality 0x0,__gxx_personality_v0
        pushl   %ebp
        .cfi_def_cfa_offset 8
        movl    %esp, %ebp
        .cfi_offset 5, -8
        .cfi_def_cfa_register 5
        pushl   %ebx
        subl    $4, %esp
        movl    12(%ebp), %eax
        cmpl    $-2, %eax
        je      .L2
        .cfi_offset 3, -12
        movl    glo_ptr_to_base, %edx
        movl    (%edx), %ebx
        movl    %edx, 8(%ebp)
        movl    (%ebx), %edx
        movl    -4(%ebp), %ebx
        leave
        .cfi_remember_state
        .cfi_restore 5
        .cfi_def_cfa 4, 4
        .cfi_restore 3
        jmp     *%edx
.L2:
        .cfi_restore_state
        movl    -4(%ebp), %ebx
        leave
        .cfi_restore 5
        .cfi_def_cfa 4, 4
        .cfi_restore 3
        ret     $12
        .cfi_endproc


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[uros at gcc dot gnu dot org]

------- Comment #12 from uros at gcc dot gnu dot org  2009-08-23 12:14 -------
Subject: Bug 40718

Author: uros
Date: Sun Aug 23 12:14:26 2009
New Revision: 151029

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=151029
Log:
        PR target/40718
        * config/i386/i386.c (*call_pop_1): Disable for sibling calls.
        (*call_value_pop_1): Ditto.
        (*sibcall_pop_1): New insn pattern.
        (*sibcall_value_pop_1): Ditto.


Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/i386/i386.md


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[uros at gcc dot gnu dot org]

------- Comment #13 from uros at gcc dot gnu dot org  2009-08-23 12:38 -------
Subject: Bug 40718

Author: uros
Date: Sun Aug 23 12:37:53 2009
New Revision: 151030

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=151030
Log:
        PR target/40718
        * config/i386/i386.c (*call_pop_1): Disable for sibling calls.
        (*call_value_pop_1): Ditto.
        (*sibcall_pop_1): New insn pattern.
        (*sibcall_value_pop_1): Ditto.

testsuite/ChangeLog:

        PR target/40718
        * gcc.target/i386/pr40718.c: New test.


Added:
    branches/gcc-4_4-branch/gcc/testsuite/gcc.target/i386/pr40718.c
Modified:
    branches/gcc-4_4-branch/gcc/ChangeLog
    branches/gcc-4_4-branch/gcc/config/i386/i386.md
    branches/gcc-4_4-branch/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[uros at gcc dot gnu dot org]

------- Comment #14 from uros at gcc dot gnu dot org  2009-08-23 13:03 -------
Subject: Bug 40718

Author: uros
Date: Sun Aug 23 13:03:39 2009
New Revision: 151033

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=151033
Log:
        PR target/40718
        * config/i386/i386.c (*call_pop_1): Disable for sibling calls.
        (*call_value_pop_1): Ditto.
        (*sibcall_pop_1): New insn pattern.
        (*sibcall_value_pop_1): Ditto.

testsuite/ChangeLog:

        PR target/40718
        * gcc.target/i386/pr40718.c: New test.


Added:
    branches/gcc-4_3-branch/gcc/testsuite/gcc.target/i386/pr40718.c
Modified:
    branches/gcc-4_3-branch/gcc/ChangeLog
    branches/gcc-4_3-branch/gcc/config/i386/i386.md
    branches/gcc-4_3-branch/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[ubizjak at gmail dot com]

------- Comment #15 from ubizjak at gmail dot com  2009-08-23 13:04 -------
Fixed everywhere.


-- 

ubizjak at gmail dot com changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718

[Bug target/40718] Invalid code produced with -foptimize-sibling-calls

[slyfox at inbox dot ru]

------- Comment #16 from slyfox at inbox dot ru  2009-08-29 10:26 -------
(In reply to comment #15)
> Fixed everywhere.
> 

Just tested on my sample (got this only revision from 4_4 branch and applied to
gentoo gcc sources).
All works as expected.

Thanks!


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40718