[Bug target/83738] [avr] Don't save registers in main

[vries at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83738

Tom de Vries <vries at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |vries at gcc dot gnu.org

--- Comment #3 from Tom de Vries <vries at gcc dot gnu.org> ---
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83737#c2 :
...
Author: gjl
Date: Tue Jan  9 10:38:45 2018
New Revision: 256373

URL: https://gcc.gnu.org/viewcvs?rev=256373&root=gcc&view=rev
Log:
gcc/
        Don't save registers in main().
        PR target/83737
        * doc/invoke.texi (AVR Options) [-mmain-is-OS_task]: Document it.
        * config/avr/avr.opt (-mmain-is-OS_task): New target option.
        * config/avr/avr.c (avr_set_current_function): Don't error if
        naked, OS_task or OS_main are specified at the same time.
        (avr_function_ok_for_sibcall): Don't disable sibcalls for OS_task,
        OS_main.
        (avr_insert_attributes) [-mmain-is-OS_task] <main>: Add OS_task
        attribute.
        * common/config/avr/avr-common.c (avr_option_optimization_table):
        Switch on -mmain-is-OS_task for optimizing compilations.


Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/common/config/avr/avr-common.c
    trunk/gcc/config/avr/avr.c
    trunk/gcc/config/avr/avr.opt
    trunk/gcc/doc/invoke.texi
...