Re: PATCH: PR target/37843:[4.4 Regression] unaligned stack in maindue to tail call optimization

[Uros Bizjak <ubizjak at gmail dot com>]

H.J. Lu wrote:

> The problem is sibcall optimization will use the incoming stack
> boundary as the outgoing stack boundary. It is OK as long as
> the incoming stack boundary >= the outgoing stack boundary.
> ix86_function_ok_for_sibcall needs to know the precise incoming
> stack boundary, which is set in expand_stack_alignment, to
> check if the incoming stack boundary >= the outgoing stack
> boundary.
>
> This patch moves updating stack boundary before
> TARGET_FUNCTION_OK_FOR_SIBCALL is called. It
> changes cfgexpand.c and i386.c. OK for trunk?
>
> Thanks.
>
>   
> 2008-10-15  H.J. Lu  <hongjiu.lu@intel.com>
>             Joey Ye  <joey.ye@intel.com>
>
>         PR target/37843
>         * cfgexpand.c (expand_stack_alignment): Move updating stack
>         boundary to ...
>         (gimple_expand_cfg): Here.
>
>         * config/i386/i386.c (ix86_function_ok_for_sibcall): Return
>         false if we need to align the outgoing stack.
>         (ix86_update_stack_boundary): Check parm_stack_boundary.
>
> gcc/testsuite/
>
> 2008-10-15  H.J. Lu  <hongjiu.lu@intel.com>
>
>         PR target/37843
>         * gcc.target/i386/align-main-3.c: New.
>         * gcc.target/i386/pr37843-1.c: Likewise.
>         * gcc.target/i386/pr37843-2.c: Likewise.
>         * gcc.target/i386/pr37843-3.c: Likewise.

x86 part is OK, but generic part needs middle-end review.

Thanks,
Uros.