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#ifndef _STDARG_H
#define _STDARG_H
typedef struct {
unsigned int gp_offset; unsigned int fp_offset;
void *overflow_arg_area; void *reg_save_area;
} __va_elem;
typedef __va_elem va_list;
typedef va_list __builtin_va_list;
typedef va_list __gnuc_va_list;
extern void __builtin_va_start(void *ap, void *last);
#define va_start(ap, last) do { void *_ap = ≈ __builtin_va_start(_ap, last); } while (0)
#define va_end(ap)
static void *__va_arg_mem(__va_elem *ap, int sz, int align) {
unsigned long p = ap->overflow_arg_area;
if (align > 8)
p = (p + 15) / 16 * 16;
ap->overflow_arg_area = ((unsigned long)p + sz + 7) / 8 * 8;
return (void*)p;
}
static void *__va_arg_gp(__va_elem *ap, int sz, int align) {
if (ap->gp_offset >= 48)
return __va_arg_mem(ap, sz, align);
void *r = ap->reg_save_area + ap->gp_offset;
ap->gp_offset += 8;
return r;
}
static void *__va_arg_fp(__va_elem *ap, int sz, int align) {
if (ap->fp_offset >= 112)
return __va_arg_mem(ap, sz, align);
void *r = ap->reg_save_area + ap->fp_offset;
ap->fp_offset += 8;
return r;
}
#define va_arg(ap, ty) \
({ \
int klass = __builtin_reg_class(ty); \
*(ty *)(klass == 0 ? __va_arg_gp(&ap, sizeof(ty), _Alignof(ty)) : \
klass == 1 ? __va_arg_fp(&ap, sizeof(ty), _Alignof(ty)) : \
__va_arg_mem(&ap, sizeof(ty), _Alignof(ty))); \
})
#endif
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