bench: isolate operation

Signed-off-by: Athan <kgryte@gmail.com>

Author: kgryte

lib/node_modules/@stdlib/number/float16/base/to-word/benchmark/c/benchmark.c

@@ -18,6 +18,7 @@
 
 #include "stdlib/number/float16/base/to_word.h"
 #include "stdlib/number/float64/base/to_float16.h"
+#include "stdlib/number/float64/ctor.h"
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdint.h>
@@ -92,19 +93,19 @@ static double rand_double( void ) {
 * @return elapsed time in seconds
 */
 static double benchmark( void ) {
-	double x[ 100 ];
+	stdlib_float16_t x[ 100 ];
 	double elapsed;
 	uint16_t w;
 	double t;
 	int i;
 
 	for ( i = 0; i < 100; i++ ) {
-		x[ i ] = ( 1000.0*rand_double() ) - 500.0;
+		x[ i ] = stdlib_base_float64_to_float16( ( 1000.0*rand_double() ) - 500.0 );
 	}
 
 	t = tic();
 	for ( i = 0; i < ITERATIONS; i++ ) {
-		stdlib_base_float16_to_word( stdlib_base_float64_to_float16( x[ i % 100 ] ), &w );
+		stdlib_base_float16_to_word( x[ i % 100 ], &w );
 		if ( w == 1 ) { // Note: should not generate the smallest subnormal
 			printf( "unexpected result\n" );
 			break;