Associative Functions implemented on ClearSpeed CSX600 Mike Yuan
Introduction Important for ATC applications asc.cn, asc.h, asc_asm.cn, carlot.h and carlot_n Overview - PickOne: get, next - AnyResponder: any, ascNany - MAX/MIN: max_int, min_int, max_float, min_float Three versions - Pure Cn (preferred): all functions in asc.cn - Assembler: max, min in asc_asm.cn - Mixed Cn and assembler: get, next, ascAny, ascNany in asc_asm.cn
Compile and run For Cn versions -bash-3.00$ cscn -o test1.csx carlot_next.cn asc.cn -bash-3.00$ csrun test1.csx For mixed and assembler versions -bash-3.00$ cscn -o test1.csx carlot_next.cn asc_asm.cn -bash-3.00$ csrun test1.csx
Get Signature: mono short get (poly const char mask) Return the first PE number of the enabled PEs
Get example codes //set the mask to only PE's with a 1991 model car. if (mycarlot.year == 1991) { mask = 1; } //get first car with the year 1991 ONE = get(mask); //set the ONE to color M if (get_penum() == ONE) { mycarlot.color = 'M'; }
Get results produced Before: 1990 L F R H O T 0 After: 1990 L F M H O T 0
Next Signature: mono short next (poly const char mask, short ONE) Return the PE number of the next PE in the mask
Next example codes //get NEXT car with 1991 year. ONE = next(mask,ONE); //set the second one to color N if (get_penum() == ONE) { mycarlot.color = 'N'; } //skip to the fourth carwith year 1991 ONE = next(mask,ONE); //set the forth car with year 1991 to Z if (get_penum() == ONE) { mycarlot.color = 'Z'; }
Next results produced Before: 1991 G D L H Y D 1 After: 1991 N D L H Z D 1
any Signature: mono char any (poly int condition); Test the condition condition on all of the enabled PEs and returns true if any of the enabled PEs return true
Example codes //set mask if (mycarlot.year == 1991) { mask = 1; } //turn off PE's not in mask if (mask) { //if there are any red and 1991 cars if(any(mycarlot.color == 'R')) { //all cars turn to color T mycarlot.color = 'T'; }
any results Before there is a: 1991 R D 1 After 1991 T H T D T H 1
ascNany Signature: mono char ascNany (poly int condition); Test the condition condition on all of the enabled PEs and returns true if all of the enabled PEs return false
ascNany (cont) Example codes: if(ascNany(mycarlot.color=='NONE')) { mycarlot.onlot = 0; } Results 1991 T H T D T H 0
Max for int/float/short Signature of max: int max_int(poly int value) Return the maximum instance of a signed poly int value
Min for int/float/short Signature of min: int min_int(poly int value) Return the minimum instance of a signed poly int value
Max/Min (cont) Example codes poly int index = get_penum(); int max_index, min_index; max_index = max_int(index); printf ("The maximum of PE number is: %d\n", max_index); min_index = min_int(index); printf ("The minimum of PE number is: %d\n", min_index); Results The maximum of PE number is: 95 The minimum of PE number is: 0
Timing Record cycles of operations Example codes: // min_int start_time = get_cycles_ila(); min_int_result = min_int(int_value); elapsed_time = get_cycles_ila() - start_time; printf("min_int Result: %2d Time: %4u\n",min_int_result, elapsed_time);
Timing (cont) Results: min_int Result: 0 Time: 6377 run csreset -v and the frequency is displayed Core clock frequency: Processor 0: MHz, Processor 1: MHz 6377/210M= ms
Random function Generate random data in PE Randp() generates random numbers between 0 and RAND_MAX Example codes: poly int rand_num = 0; rand_num = randp(); plane.speed[i] = (scale * (rand_num*( )/RAND_MAX + 30));
Random number (cont) Problem: average is median: ( )/2=285, not 250 Use Poisson distribution or Weibu distribution to get average=250
Handle timer Do timing in host for accuracy Two semaphores sem_start, sem_end between host and PE Host signals sem_start and records time PE waits for it and then execute PE signals sem_end Host waits for sem_end
Handle timer (cont) Host records time How much time spent? If > 0.5s, error Else if< 0.5s, wait for rest of time
Task scheduling One.csx file A count for every 0.5s If count=8, do terrain avoidance If count=16, do conflict detection and correlation