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/* Assembler macros for PA-RISC.
Copyright (C) 1999 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper, <drepper@cygnus.com>, August 1999.
Linux/PA-RISC changes by Philipp Rumpf, <prumpf@tux.org>, March 2000.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <asm/unistd.h>
#include <sysdeps/generic/sysdep.h>
#include <sys/syscall.h>
#include "config.h"
#ifndef ASM_LINE_SEP
#define ASM_LINE_SEP ;
#endif
#undef SYS_ify
#define SYS_ify(syscall_name) (__NR_##syscall_name)
#ifdef __ASSEMBLER__
/* Syntactic details of assembler. */
#define ALIGNARG(log2) log2
/* For Linux we can use the system call table in the header file
/usr/include/asm/unistd.h
of the kernel. But these symbols do not follow the SYS_* syntax
so we have to redefine the `SYS_ify' macro here. */
#undef SYS_ify
#define SYS_ify(syscall_name) __NR_##syscall_name
/* ELF-like local names start with `.L'. */
#undef L
#define L(name) .L##name
/* Linux uses a negative return value to indicate syscall errors,
unlike most Unices, which use the condition codes' carry flag.
Since version 2.1 the return value of a system call might be
negative even if the call succeeded. E.g., the `lseek' system call
might return a large offset. Therefore we must not anymore test
for < 0, but test for a real error by making sure the value in %eax
is a real error number. Linus said he will make sure the no syscall
returns a value in -1 .. -4095 as a valid result so we can safely
test with -4095. */
/* We don't want the label for the error handle to be global when we define
it here. */
#ifdef PIC
# define SYSCALL_ERROR_LABEL 0f
#else
# define SYSCALL_ERROR_LABEL syscall_error
#endif
/* Define an entry point visible from C.
There is currently a bug in gdb which prevents us from specifying
incomplete stabs information. Fake some entries here which specify
the current source file. */
#define ENTRY(name) \
.text ASM_LINE_SEP \
.export C_SYMBOL_NAME(name) ASM_LINE_SEP \
.type C_SYMBOL_NAME(name),@function ASM_LINE_SEP \
C_LABEL(name) \
CALL_MCOUNT
#define ret \
bv 0(2) ASM_LINE_SEP \
nop
#undef END
#define END(name) \
1: .size C_SYMBOL_NAME(name),1b-C_SYMBOL_NAME(name)
/* If compiled for profiling, call `mcount' at the start of each function. */
#ifdef PROF
/* The mcount code relies on a normal frame pointer being on the stack
to locate our caller, so push one just for its benefit. */
#define CALL_MCOUNT /* XXX */
#else
#define CALL_MCOUNT /* Do nothing. */
#endif
/* syscall wrappers consist of
#include <sysdep.h>
PSEUDO(...)
ret
PSEUDO_END(...)
which means
ENTRY(name)
DO_CALL(...)
nop
bv 0(2)
nop
*/
#define PSEUDO(name, syscall_name, args) \
ENTRY (name) \
DO_CALL(args, syscall_name) ASM_LINE_SEP \
nop
#undef PSEUDO_END
#define PSEUDO_END(name) \
END (name)
#define JUMPTARGET(name) name
#define SYSCALL_PIC_SETUP /* Nothing. */
/* Linux takes system call arguments in registers:
syscall number gr20
arg 1 gr26
arg 2 gr25
arg 3 gr24
arg 4 gr23
arg 5 gr22
arg 6 gr21
The compiler calls us by the C convention:
syscall number in the DO_CALL macro
arg 1 gr26
arg 2 gr25
arg 3 gr24
arg 4 gr23
arg 5 -52(gr30)
arg 6 -56(gr30)
gr22 and gr21 are caller-saves, so we can just load the arguments
there and generally be happy. */
/* the cmpb...no_error code below inside DO_CALL
* is intended to mimic the if (__sys_res...)
* code inside INLINE_SYSCALL
*/
#undef DO_CALL
#define DO_CALL(args, syscall_name) \
DOARGS_##args \
ble 0x100(%sr2,%r0) ASM_LINE_SEP \
ldi SYS_ify (syscall_name), %r20 ASM_LINE_SEP \
ldi -0x1000,%r1 ASM_LINE_SEP \
cmpb,>>=,n %r1,%ret0,0f ASM_LINE_SEP \
stw %rp, -20(%sr0,%r30) ASM_LINE_SEP \
stw %ret0, -24(%sr0,%r30) ASM_LINE_SEP \
.import __errno_location,code ASM_LINE_SEP \
bl __errno_location,%rp ASM_LINE_SEP \
ldo 64(%r30), %r30 ASM_LINE_SEP \
ldo -64(%r30), %r30 ASM_LINE_SEP \
ldw -24(%r30), %r26 ASM_LINE_SEP \
sub %r0, %r26, %r26 ASM_LINE_SEP \
stw %r26, 0(%sr0,%ret0) ASM_LINE_SEP \
ldo -1(%r0), %ret0 ASM_LINE_SEP \
ldw -20(%r30), %rp ASM_LINE_SEP \
0: ASM_LINE_SEP \
UNDOARGS_##args
#define DOARGS_0 /* nothing */
#define DOARGS_1 /* nothing */
#define DOARGS_2 /* nothing */
#define DOARGS_3 /* nothing */
#define DOARGS_4 /* nothing */
#define DOARGS_5 ldw -52(%r30), %r22 ASM_LINE_SEP
#define DOARGS_6 ldw -52(%r30), %r22 ASM_LINE_SEP \
ldw -56(%r30), %r21 ASM_LINE_SEP
#define UNDOARGS_0 /* nothing */
#define UNDOARGS_1 /* nothing */
#define UNDOARGS_2 /* nothing */
#define UNDOARGS_3 /* nothing */
#define UNDOARGS_4 /* nothing */
#define UNDOARGS_5 /* nothing */
#define UNDOARGS_6 /* nothing */
#else
#undef INLINE_SYSCALL
#define INLINE_SYSCALL(name, nr, args...) ({ \
unsigned long __sys_res; \
{ \
register unsigned long __res asm("r28"); \
LOAD_ARGS_##nr(args) \
asm volatile( \
"ble 0x100(%%sr2, %%r0)\n\t" \
" ldi %1, %%r20" \
: "=r" (__res) \
: "i" (SYS_ify(name)) ASM_ARGS_##nr \
); \
__sys_res = __res; \
} \
if (__sys_res >= (unsigned long)-4095) { \
__set_errno(-__sys_res); \
__sys_res == (unsigned long)-1; \
} \
__sys_res; \
})
#define LOAD_ARGS_0()
#define LOAD_ARGS_1(r26) \
register unsigned long __r26 __asm__("r26") = (unsigned long)r26; \
LOAD_ARGS_0()
#define LOAD_ARGS_2(r26,r25) \
register unsigned long __r25 __asm__("r25") = (unsigned long)r25; \
LOAD_ARGS_1(r26)
#define LOAD_ARGS_3(r26,r25,r24) \
register unsigned long __r24 __asm__("r24") = (unsigned long)r24; \
LOAD_ARGS_2(r26,r25)
#define LOAD_ARGS_4(r26,r25,r24,r23) \
register unsigned long __r23 __asm__("r23") = (unsigned long)r23; \
LOAD_ARGS_3(r26,r25,r24)
#define LOAD_ARGS_5(r26,r25,r24,r23,r22) \
register unsigned long __r22 __asm__("r22") = (unsigned long)r22; \
LOAD_ARGS_4(r26,r25,r24,r23)
#define LOAD_ARGS_6(r26,r25,r24,r23,r22,r21) \
register unsigned long __r21 __asm__("r21") = (unsigned long)r21; \
LOAD_ARGS_5(r26,r25,r24,r23,r22)
#define ASM_ARGS_0
#define ASM_ARGS_1 , "r" (__r26)
#define ASM_ARGS_2 , "r" (__r26), "r" (__r25)
#define ASM_ARGS_3 , "r" (__r26), "r" (__r25), "r" (__r24)
#define ASM_ARGS_4 , "r" (__r26), "r" (__r25), "r" (__r24), "r" (__r23)
#define ASM_ARGS_5 , "r" (__r26), "r" (__r25), "r" (__r24), "r" (__r23), "r" (__r22)
#define ASM_ARGS_6 , "r" (__r26), "r" (__r25), "r" (__r24), "r" (__r23), "r" (__r22), "r" (__r21)
#endif /* __ASSEMBLER__ */
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