Category : Files from Magazines
Archive   : SCBENCH.ZIP
Filename : FLOAT88.C

/*
** BYTE Small-C Floating-Point Benchmark
** Version 1 for 8088/8086/80286
** March, 1988
** Written in BYTE Small-C
** Based on Small-C by J.E. Hendrix
**
** Operation:
** 1. Initialize the coprocessor.
** 2. Execute fourbang(), which:
** a. Generates space for temporaries and constants.
** b. Turns on stopwatch.
** c. Executes loop FCOUNT times. Loop consists of:
** 8 each of floating add, subtract, multiply, divide.
** d. Turns off stopwatch.
** e. Calculates time for an empty loop.
** f. Reports time and result of operations.
** 3. Executes finteg(), which:
** a. Generates space for temporaries and constants.
** b. Turns on stopwatch.
** c. Executes a trapezoidal integration method for sin(x)
** from 0 to pi/2.
** d. Turns off stopwatch.
** e. Calculates time for an empty loop.
** f. Reports time and result of operation.
** g. Turns on stopwatch.
** h. Executes a trapezoidal integration method for e^(x)
** from 0 to 1.
** i. Turns off stopwatch.
** j. Calculates time for an empty loop.
** k. Reports time and result of operation.
** 4. Exits.
**
** NOTE:
** Since Small-C does not support floating-point, we simply
** manipluate floating-point numbers as 4-element integer
** arrays. The floating-point library functions handle the
** actual calls to the coprocessor, including the routine
** to print out a floating-point number.
**
** Expected results:
** For first test: 1.000000000E1 (10.0)
** For trapezoidal of sine(x): 1.000000000E0 (1.0)
** For trapezoidal of e^x: 1.718281828E0 (e-1)
*/

#include stdio.h

#define FCOUNT 20000 /* Number of times the four-banger test */
/* is repeated. */
#define ICOUNT 32000 /* Stepsize for the integration test */

/* Timer holding variables */
int tblock[4];
int mtblock[4]; /* For empty loop timing */

main()
{
/* Announce yourself */
printf("BYTE Small-C Floating-Point Coprocessor Benchmark\n\n");

/* Initialize the math coprocessor */
finit();

/* Do four-banger test */
fourbang();

/* Do integration */
finteg();

/* Go home */
finit();

printf("Press RETURN to exit:");
fgetc(stdin);

exit(0);
}

/*
** fourbang()
** Executes a loop of floating add, subtract, multiplies, and divides.
*/
fourbang()
{
int ten[4]; /* Holder for 10 */
int one[4]; /* Holder for one */
int temp[4]; /* Temporary storage */
int i;

/* Announce yourself */
printf("Basic Math Test (+,-,*,/)\n");

/* First set up constants */
ten[0]=10;
ten[1]=ten[2]=ten[3]=0;
fint2float(ten);
fconst(1);
fstore(one);

/* Initialize temp location */
fload(ten);
fstore(temp);

gtime(tblock);
/* Do the operation */
for(i=0;i {
f2add(temp,one,temp);
f2sub(temp,one,temp);
f2mult(temp,ten,temp);
f2div(temp,ten,temp);
f2sub(temp,one,temp);
f2mult(temp,ten,temp);
f2add(temp,ten,temp);
f2div(temp,ten,temp);
f2add(temp,one,temp);
f2sub(temp,one,temp);
f2mult(temp,ten,temp);
f2div(temp,ten,temp);
f2sub(temp,one,temp);
f2mult(temp,ten,temp);
f2add(temp,ten,temp);
f2div(temp,ten,temp);
f2add(temp,one,temp);
f2sub(temp,one,temp);
f2mult(temp,ten,temp);
f2div(temp,ten,temp);
f2sub(temp,one,temp);
f2mult(temp,ten,temp);
f2add(temp,ten,temp);
f2div(temp,ten,temp);
f2add(temp,one,temp);
f2sub(temp,one,temp);
f2mult(temp,ten,temp);
f2div(temp,ten,temp);
f2sub(temp,one,temp);
f2mult(temp,ten,temp);
f2add(temp,ten,temp);
f2div(temp,ten,temp);
}
calctim(tblock);

/* Now calculate an empty loop */
gtime(mtblock);
for(i=0;i calctim(mtblock);

/* Report results */
printf("***Results: (All times are HH:MM:SS:1/100ths\n");

printf("Total time: %d:%d:%d:%d\n",tblock[0],tblock[1],
tblock[2],tblock[3]);

printf("Empty loop time: %d:%d:%d:%d\n",mtblock[0],mtblock[1],
mtblock[2],mtblock[3]);
printf("Value:");
fltprint(10,temp);
printf("\n\n");

return;
}

/*
** finteg()
** Do integration.
**
*/

finteg()
{

int two[4]; /* Holder for two */
int pitwo[4]; /* Holder for pi/2 */
int temp[4]; /* Temp location */
int sinex[4]; /* Sine value */
int ex[4]; /* e^x value */
int accum[4]; /* Accumulator */
int x[4]; /* Holder for x */
int i;

/* Announce yourself */
printf("Trapezoidal rule for sin(x) 0->x->pi/2 \n");

/* Generate 2 */
two[0]=2;
two[1]=two[2]=two[3]=0;
fint2float(two);

/* Generate pi/2 */
fgetpi2(); /* Get pi over two */
fstore(pitwo); /* Store pi over two */

/* Generate stepsize */
temp[0]=ICOUNT;
temp[1]=temp[2]=temp[3]=0;
fint2float(temp);
f2div(pitwo,temp,temp); /* Stepsize in temp */

/* Clear accumulator */
fconst(0);
fstore(accum);

/* Store x(0) */
fconst(0);
fstore(x);

/* Do trapezoidal rule for sine(x) */
gtime(tblock);
for(i=0;i {
fsin(x,sinex); /* Get sinex */
f2add(accum,sinex,accum);
if((i!=0)&&(i!=ICOUNT))
f2add(accum,sinex,accum);
f2add(x,temp,x); /* Increment by step */
}
f2mult(accum,temp,accum); /* Times stepsize */
f2div(accum,two,accum); /* Divided by 2 */

/* Calculate time */
calctim(tblock);

/* Get time for an empty loop */
gtime(mtblock);
for(i=0;i calctim(mtblock);

/* Report results */
printf("**** Results: (All times are HH:MM:SS:1/100ths)\n");

printf("Total time: %d:%d:%d:%d\n",tblock[0],tblock[1],
tblock[2],tblock[3]);
printf("Empty loop time: %d:%d:%d:%d\n",mtblock[0],mtblock[1],
mtblock[2],mtblock[3]);

printf("Value:");
fltprint(10,accum);
printf("\n\n");

/* Now do trapezoidal rule for e^x */

printf("Trapezoidal rule for e^x 0->x->1\n");

/* Generate stepsize */
temp[0]=ICOUNT;
temp[1]=temp[2]=temp[3]=0;
fint2float(temp);
fconst(1);

fdiv(temp);
fstore(temp); /* Stepsize in temp */

/* Clear accumulator */
fconst(0);
fstore(accum);

/* Store x(0) */
fconst(0);
fstore(x);

/* Do trapezoidal rule */
gtime(tblock);
for(i=0;i {
fex(x,ex); /* Get sinex */
f2add(accum,ex,accum);
if((i!=0)&&(i!=ICOUNT))
f2add(accum,ex,accum);
f2add(x,temp,x); /* Increment by step */
}
f2mult(accum,temp,accum); /* Times stepsize */
f2div(accum,two,accum); /* Divided by 2 */

/* Calculate time */
calctim(tblock);

/* Get time for an empty loop */
gtime(mtblock);
for(i=0;i calctim(mtblock);

/* Report results */
printf("**** Results: (All times are HH:MM:SS:1/100ths)\n");

printf("Total time: %d:%d:%d:%d\n",tblock[0],tblock[1],
tblock[2],tblock[3]);
printf("Empty loop time: %d:%d:%d:%d\n",mtblock[0],mtblock[1],
mtblock[2],mtblock[3]);

printf("Value:");
fltprint(10,accum);
printf("\n\n");

/* Go home */
return;
}

/*
** fgetpi2()
** Puts the value pi/2 on top of the floating-point stack.
*/
fgetpi2()
{
int two[4]; /* Holder for 2 */

two[0]=2;
two[1]=two[2]=two[3]=0;
fint2float(two);

fconst(2); /* Get pi on top of stack */
fdiv(two); /* pi/2 now on floating point stack top */
return;
}