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#include <machine/asm.h>
#define COMPAT_43
#include <sys/syscall.h>
#define CHMK() call_pal 0x83
#undef SYSCALL
/* Kernel syscall interface:
Input:
v0 - system call number
a* - arguments, as in C
Output:
a3 - zero iff successful
v0 - errno value on failure, else result
This macro is similar to SYSCALL in asm.h, but not completely.
There's room for optimization, if we assume this will continue to
be assembled as one file.
This macro expansions does not include the return instruction.
If there's no other work to be done, use something like:
SYSCALL(foo) ; ret
If there is other work to do (in fork, maybe?), do it after the
SYSCALL invocation. */
#define SYSCALL(x) \
.align 4 ;\
.globl machdep_sys_##x ;\
.ent machdep_sys_##x, 0 ;\
machdep_sys_##x: ;\
.frame sp,0,ra ;\
ldiq v0, SYS_##x ;\
CHMK() ;\
beq a3, Lsys_noerr_##x ;\
br gp, Lsys_err_##x ;\
Lsys_err_##x: ;\
/* Load gp so we can find cerror to jump to. */;\
ldgp gp, 0(gp) ;\
jmp zero, machdep_cerror ;\
Lsys_noerr_##x:
#define SIMPLE_SYSCALL(x) SYSCALL(x) ; ret ; .end machdep_sys_##x
#define XSYSCALL(x) SIMPLE_SYSCALL(x)
XSYSCALL(SYSCALL_NAME)
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