#include "lib_glob.h"
#include "sdl_glob.h"

#define a_value 1664525
#define c_value 32767

.SEGMENT/CODE Code_Space_Name;
.FILE RTL_FILENAME;

.GLOBAL _rand, _srand;

_srand: ram_ireg=___lib_rand_seed;
JUMP (PC, restore_state) (DB);
FETCH_RETURN
rammem(ram_ireg,ram_0)=R4;

_rand: ram_ireg=___lib_rand_seed;
R2=a_value; /*Base*/
R0=rammem(ram_ireg,ram_0); /*Read seed value*/
R0=R0*R2 (UUI); /*Compute mod(a*x)*/
R2=c_value;
R0=R0+R2, FETCH_RETURN /*Compute mod(a*x + c)*/
rammem(ram_ireg,ram_0)=R0; /*Write out new seed*/
R0=BCLR R0 BY 31; /*Always return positive*/

restore_state: RETURN (DB);
RESTORE_STACK
RESTORE_FRAME
.ENDSEG;

.SEGMENT/RAM_SPACE Ram_Space_Name;

.GLOBAL ___lib_rand_seed;
.VAR ___lib_rand_seed = 1;

.ENDSEG;