[Bug target/113780] New: [ARM] Incorrect indirect tailcall generated for PAC-enabled function.

[Bug target/113780] New: [ARM] Incorrect indirect tailcall generated for PAC-enabled function.

[belagod at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113780

            Bug ID: 113780
           Summary: [ARM] Incorrect indirect tailcall generated for
                    PAC-enabled function.
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: belagod at gcc dot gnu.org
  Target Milestone: ---

For this piece of code:

void fail(void (*f)(int, int, int, int))
{
  f(1, 2, 3, 4);
}

compiled with -mcpu=cortex-m85 -mbranch-protection=pac-ret+leaf -O2 on trunk,
it generates:

fail:
        pac     ip, lr, sp
        movs    r3, #4
        movs    r2, #3
        movs    r1, #2
        movs    r0, #1
        push    {ip, lr}
        pop     {ip, lr}
        aut     ip, lr, sp
        bx      ip  @ indirect register sibling call

[Bug target/113780] [ARM] Incorrect indirect tailcall generated for PAC-enabled function.

[belagod at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113780

Tejas Belagod <belagod at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |belagod at gcc dot gnu.org
   Last reconfirmed|                            |2024-02-06
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW

[Bug target/113780] [ARM] Incorrect indirect tailcall generated for PAC-enabled function.

[belagod at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113780

Tejas Belagod <belagod at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED

[Bug target/113780] [ARM] Incorrect indirect tailcall generated for PAC-enabled function.

[belagod at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113780

--- Comment #1 from Tejas Belagod <belagod at gcc dot gnu.org> ---
Testing a fix as we speak..

[Bug target/113780] [ARM] Incorrect indirect tailcall generated for PAC-enabled function.

[rearnsha at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113780

Richard Earnshaw <rearnsha at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |keithp at keithp dot com

--- Comment #2 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
*** Bug 113795 has been marked as a duplicate of this bug. ***

[Bug target/113780] [ARM] Incorrect indirect tailcall generated for PAC-enabled function.

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113780

--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Tejas Belagod <belagod@gcc.gnu.org>:

https://gcc.gnu.org/g:f436a2ab6ad15968275c9bbf3bd56647e5559e68

commit r14-9022-gf436a2ab6ad15968275c9bbf3bd56647e5559e68
Author: Tejas Belagod <tejas.belagod@arm.com>
Date:   Thu Jan 25 16:05:36 2024 +0530

    Arm: Fix incorrect tailcall-generation for indirect calls [PR113780]

    This patch fixes a bug that causes indirect calls in PAC-enabled functions
    to be tailcalled incorrectly when all argument registers R0-R3 are used.

    2024-02-07  Tejas Belagod  <tejas.belagod@arm.com>

            PR target/113780
            * config/arm/arm.cc (arm_function_ok_for_sibcall): Don't allow
tailcalls
            for indirect calls with 4 or more arguments in pac-enabled
functions.

            * lib/target-supports.exp (v8_1m_main_pacbti): Add
__ARM_FEATURE_PAUTH.
            * gcc.target/arm/pac-sibcall.c: New.

[Bug target/113780] [ARM] Incorrect indirect tailcall generated for PAC-enabled function.

[belagod at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113780

Tejas Belagod <belagod at gcc dot gnu.org> changed:

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

--- Comment #4 from Tejas Belagod <belagod at gcc dot gnu.org> ---
Fixed on trunk