#include "srl_barrier.h"
/*
int srl_barrier_init(srl_barrier_t barrier)
{

    register int* pinit 	= (int*)&barrier->init_val;
    register int* pcount 	= (int*)&barrier->count;

    // parallel initialisation using atomic instructions LL/SC
    asm volatile ("_barrier_init_test:          	\n"
                  "ll   $2,     0(%0)           	\n"	// read initial value
                  "bnez $2,     _barrier_init_done	\n"
                  "move $3,     %2			\n"
                  "sc   $3,     0(%0)    	      	\n"	// try to write initial value
                  "beqz $3,     _barrier_init_test	\n"
                  "move $3,	%2			\n"
                  "sw   $3,	0(%1)			\n"	// write count
				  "sync"
                  "_barrier_init_done:			\n"
                  ::"r"(pinit),"r"(pcount),"r"(value):"$2","$3");
    return 0 ;
}
*/

void srl_barrier_wait( srl_barrier_t barrier)
{
    register int* pcount 	= (int*)&barrier->count;
    register int  maxcount 	= (int)barrier->init_val;
    register int  count;

    // parallel decrement barrier counter using atomic instructions LL/SC
    // input : pointer on the barrier counter 
    // output : counter value 
    asm volatile ("_barrier_decrement:          		\n"
                  "ll   %0,     0(%1)           		\n"
                  "addi $3,     %0,     -1      		\n"
                  "sc   $3,     0(%1)           		\n"
                  "beqz $3,     _barrier_decrement		\n"
                  :"=r"(count):"r"(pcount):"$2","$3");

    // the last task re-initializes the barrier counter 
    // to the max value, waking up all other waiting tasks

//TODO:check it out
    if ( count == 0 ) 	 // last task
    {
        //*pcount = maxcount;
		asm volatile( "sw %0,	(%1)\n"
					  "sync			\n"
					  ::"r"(maxcount),"r"(pcount));
        return ;
    }
    else 		// other tasks
    {
//        while ( *pcount != maxcount ) 	{ }	// busy waiting 
		srl_sched_wait_eq(pcount, maxcount);	// busy waiting 
        return ;
    }

}