struct fp_ext *
fp_fsglmul(struct fp_ext *dest, struct fp_ext *src)
{
	int exp;

	dprint(PINSTR, "fsglmul\n");

	fp_dyadic_check(dest, src);

	/* calculate the correct sign now, as it's necessary for infinities */
	dest->sign = src->sign ^ dest->sign;

	/* Handle infinities */
	if (IS_INF(dest)) {
		if (IS_ZERO(src))
			fp_set_nan(dest);
		return dest;
	}
	if (IS_INF(src)) {
		if (IS_ZERO(dest))
			fp_set_nan(dest);
		else
			fp_copy_ext(dest, src);
		return dest;
	}

	/* Of course, as we all know, zero * anything = zero.  You may
	   not have known that it might be a positive or negative
	   zero... */
	if (IS_ZERO(dest) || IS_ZERO(src)) {
		dest->exp = 0;
		dest->mant.m64 = 0;
		dest->lowmant = 0;

		return dest;
	}

	exp = dest->exp + src->exp - 0x3ffe;

	/* do a 32-bit multiply */
	fp_mul64(dest->mant.m32[0], dest->mant.m32[1],
		 dest->mant.m32[0] & 0xffffff00,
		 src->mant.m32[0] & 0xffffff00);

	if (exp >= 0x7fff) {
		fp_set_ovrflw(dest);
		return dest;
	}
	dest->exp = exp;
	if (exp < 0) {
		fp_set_sr(FPSR_EXC_UNFL);
		fp_denormalize(dest, -exp);
	}

	return dest;
}
Esempio n. 2
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struct fp_ext *
fp_fsglmul(struct fp_ext *dest, struct fp_ext *src)
{
	int exp;

	dprint(PINSTR, "fsglmul\n");

	fp_dyadic_check(dest, src);

	/*                                                                  */
	dest->sign = src->sign ^ dest->sign;

	/*                   */
	if (IS_INF(dest)) {
		if (IS_ZERO(src))
			fp_set_nan(dest);
		return dest;
	}
	if (IS_INF(src)) {
		if (IS_ZERO(dest))
			fp_set_nan(dest);
		else
			fp_copy_ext(dest, src);
		return dest;
	}

	/*                                                            
                                                          
            */
	if (IS_ZERO(dest) || IS_ZERO(src)) {
		dest->exp = 0;
		dest->mant.m64 = 0;
		dest->lowmant = 0;

		return dest;
	}

	exp = dest->exp + src->exp - 0x3ffe;

	/*                      */
	fp_mul64(dest->mant.m32[0], dest->mant.m32[1],
		 dest->mant.m32[0] & 0xffffff00,
		 src->mant.m32[0] & 0xffffff00);

	if (exp >= 0x7fff) {
		fp_set_ovrflw(dest);
		return dest;
	}
	dest->exp = exp;
	if (exp < 0) {
		fp_set_sr(FPSR_EXC_UNFL);
		fp_denormalize(dest, -exp);
	}

	return dest;
}