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extern int main(int argc, char **argv, char **envp);
extern int brk (void *value);
extern char bss_start;
extern char end;
char *__env[1] = {0};
char **environ = __env;
#define ENABLE_TRACE_MASK 1
__inline static void
enable_tracing (void)
{
register int mask = ENABLE_TRACE_MASK;
__asm__ volatile ("modpc %0,%0,%0"
:
: "d" (mask));
}
#define STACK_ALIGN 64
__inline static void
set_stack (void* ptr)
{
ptr = (void *)(((int)ptr + STACK_ALIGN - 1) & ~(STACK_ALIGN - 1));
/* SP must be 64 bytes larger than FP at start. */
__asm__ volatile ("mov %0,sp"
:
: "d" (ptr+STACK_ALIGN));
__asm__ volatile ("mov %0,fp"
:
: "d" (ptr));
}
__inline static void
init_Cregs (void)
{
/* set register values gcc like */
register unsigned int mask0=0x3b001000;
register unsigned int mask1=0x00009107;
__asm__ volatile ("mov %0,g14"
: /* no output */
: "I" (0)); /* gnu structure pointer */
__asm__ volatile ("modac %1,%0,%0"
: /* no output */
: "d" (mask0),
"d" (mask1)); /* fpu control kb */
}
void
_start(void)
{
char *p;
enable_tracing ();
set_stack (&end);
init_Cregs ();
/* The stack grows upwards, so this makes the heap start after a 256K
stack area. PlumHall known to fail with less than 73K of stack. */
brk (&end+0x40000);
/* clear bss */
memset (&bss_start, 0, &end - &bss_start);
main(0, 0, 0);
exit(0);
}
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