view ext/clapack/src/pow_di.c @ 461:9414df58fd0e

Fix an issue is a mutithreading context

The global profile buffers where used concurrently by different threads
leading to wrong detection results. This is fixed by using a local copy
of the buffers. In addition, this commit also includes some minor
performance improvements.

#include "f2c.h"
#ifdef __cplusplus
extern "C" {
#endif

#ifdef KR_headers
double pow_di(ap, bp) doublereal *ap; integer *bp;
#else
double pow_di(doublereal *ap, integer *bp)
#endif
{
double pow, x;
integer n;
unsigned long u;

pow = 1;
x = *ap;
n = *bp;

if(n != 0)
	{
	if(n < 0)
		{
		n = -n;
		x = 1/x;
		}
	for(u = n; ; )
		{
		if(u & 01)
			pow *= x;
		if(u >>= 1)
			x *= x;
		else
			break;
		}
	}
return(pow);
}
#ifdef __cplusplus
}
#endif