rl78-sys.h

/*

Copyright (c) 2011 Red Hat Incorporated.
All rights reserved.

Redistribution and use in source and binary forms, with or without 
modification, are permitted provided that the following conditions are met: 

    Redistributions of source code must retain the above copyright 
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    Redistributions in binary form must reproduce the above copyright
    notice, this list of conditions and the following disclaimer in the
    documentation and/or other materials provided with the distribution.

    The name of Red Hat Incorporated may not be used to endorse 
    or promote products derived from this software without specific 
    prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED.  IN NO EVENT SHALL RED HAT INCORPORATED BE LIABLE FOR ANY
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 

*/
/**
 * \author DJ Delorie <dj@redhat.com>
 */

r8      =       0xffef0
r9      =       0xffef1
r10     =       0xffef2
r11     =       0xffef3
r12     =       0xffef4
r13     =       0xffef5
r14     =       0xffef6
r15     =       0xffef7
r16     =       0xffee8
r17     =       0xffee9
r18     =       0xffeea
r19     =       0xffeeb
r20     =       0xffeec
r21     =       0xffeed
r22     =       0xffeee
r23     =       0xffeef

#define SYS__exit  SYS_exit

        .macro syscall_body  number
         /* The RL78 doesn't really have an "interrupt" upcode, just
            BRK, which we emulate exactly.  We use the STOP opcode,
            which is a breakpoint in the simulator.  */
        mov     A, #\number
        stop
        ret
        .endm
      
        .macro do_syscall  name number
__\name:
        .global __\name
_\name:
        .weak _\name
        syscall_body \number
        .endm

   .macro       syscall_returns name number
__\name:
        .global __\name
_\name:
        .weak _\name
        mov     r8, #\number
        ret
        .endm

#define S(name)         do_syscall      name, SYS_##name
#define SYSCALL(number) syscall_body    number
#define ERR(name)       syscall_returns name, -1
#define OK(name)        syscall_returns name, 0
#define RET(name,val)   syscall_returns name, val