fdiv.c

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/* $Id: fdiv.c,v 1.1 1999/08/23 18:59:33 cort Exp $
 */

#include <linux/types.h>
#include <linux/errno.h>
#include <asm/uaccess.h>

#include "soft-fp.h"
#include "double.h"

int
fdiv(void *frD, void *frA, void *frB)
{
	FP_DECL_D(A);
	FP_DECL_D(B);
	FP_DECL_D(R);
	int ret = 0;

#ifdef DEBUG
	printk("%s: %p %p %p\n", __FUNCTION__, frD, frA, frB);
#endif

	__FP_UNPACK_D(A, frA);
	__FP_UNPACK_D(B, frB);

#ifdef DEBUG
	printk("A: %ld %lu %lu %ld (%ld)\n", A_s, A_f1, A_f0, A_e, A_c);
	printk("B: %ld %lu %lu %ld (%ld)\n", B_s, B_f1, B_f0, B_e, B_c);
#endif

	if (A_c == FP_CLS_ZERO && B_c == FP_CLS_ZERO) {
		ret |= EFLAG_VXZDZ;
#ifdef DEBUG
		printk("%s: FPSCR_VXZDZ raised\n", __FUNCTION__);
#endif
	}
	if (A_c == FP_CLS_INF && B_c == FP_CLS_INF) {
		ret |= EFLAG_VXIDI;
#ifdef DEBUG
		printk("%s: FPSCR_VXIDI raised\n", __FUNCTION__);
#endif
	}

	if (B_c == FP_CLS_ZERO && A_c != FP_CLS_ZERO) {
		ret |= EFLAG_DIVZERO;
		if (__FPU_TRAP_P(EFLAG_DIVZERO))
			return ret;
	}
	FP_DIV_D(R, A, B);

#ifdef DEBUG
	printk("D: %ld %lu %lu %ld (%ld)\n", R_s, R_f1, R_f0, R_e, R_c);
#endif

	return (ret | __FP_PACK_D(frD, R));
}