contrib/gdtoa/strtod.c

72 	double rv;
75 	rv = ulp(x);
77 		return rv; /* Is there an example where i <= 0 ? */
80 	return rv * u.d;
100 	U adj, aadj1, rv, rv0;
146 	dval(&rv) = 0.;
195 				ULtod(((U*)&rv)->L, bits, exp, i);
308 					word0(&rv) = 0x7ff00000;
309 					word1(&rv) = 0;
320 						word0(&rv) = 0x7ff80000 | bits[1];
321 						word1(&rv) = bits[0];
325 						word0(&rv) = NAN_WORD0;
326 						word1(&rv) = NAN_WORD1;
350 	dval(&rv) = y;
356 		dval(&rv) = tens[k - 9] * dval(&rv) + z;
377 					rv.d = -rv.d;
381 				/* rv = */ rounded_product(dval(&rv), tens[e]);
393 					rv.d = -rv.d;
398 				dval(&rv) *= tens[i];
404 				word0(&rv) -= P*Exp_msk1;
405 				/* rv = */ rounded_product(dval(&rv), tens[e]);
406 				if ((word0(&rv) & Exp_mask)
409 				word0(&rv) += P*Exp_msk1;
411 				/* rv = */ rounded_product(dval(&rv), tens[e]);
421 				rv.d = -rv.d;
425 			/* rv = */ rounded_quotient(dval(&rv), tens[-e]);
453 	/* Get starting approximation = rv * 10**e1 */
457 			dval(&rv) *= tens[i];
467 					word0(&rv) = Big0;
468 					word1(&rv) = Big1;
471 					word0(&rv) = Exp_mask;
472 					word1(&rv) = 0;
475 				word0(&rv) = Exp_mask;
476 				word1(&rv) = 0;
484 				word0(&rv) = Big0;
485 				word1(&rv) = Big1;
503 					dval(&rv) *= bigtens[j];
505 			word0(&rv) -= P*Exp_msk1;
506 			dval(&rv) *= bigtens[j];
507 			if ((z = word0(&rv) & Exp_mask)
513 				word0(&rv) = Big0;
514 				word1(&rv) = Big1;
517 				word0(&rv) += P*Exp_msk1;
523 			dval(&rv) /= tens[i];
532 					dval(&rv) *= tinytens[j];
533 			if (scale && (j = 2*P + 1 - ((word0(&rv) & Exp_mask)
535 				/* scaled rv is denormal; zap j low bits */
537 					word1(&rv) = 0;
539 					 word0(&rv) = (P+2)*Exp_msk1;
541 					 word0(&rv) &= 0xffffffff << (j-32);
544 					word1(&rv) &= 0xffffffff << j;
549 					dval(&rv) *= tinytens[j];
551 			dval(&rv0) = dval(&rv);
552 			dval(&rv) *= tinytens[j];
553 			if (!dval(&rv)) {
554 				dval(&rv) = 2.*dval(&rv0);
555 				dval(&rv) *= tinytens[j];
557 				if (!dval(&rv)) {
559 					dval(&rv) = 0.;
563 				word0(&rv) = Tiny0;
564 				word1(&rv) = Tiny1;
573 	/* Now the hard part -- adjusting rv to the correct value.*/
582 		bb = d2b(dval(&rv), &bbe, &bbbits);	/* rv = bb * 2^bbe */
606 		i = j + bbbits - 1;	/* logb(rv) */
625 		i = j + bbbits - 1;	/* logb(&rv) */
682 					if (!word1(&rv)
683 					 && !(word0(&rv) & Frac_mask)) {
684 						y = word0(&rv) & Exp_mask;
698 					if (scale && (y = word0(&rv) & Exp_mask)
703 					if ((word0(&rv) & Exp_mask) <=
705 						word0(&rv) += P*Exp_msk1;
706 						dval(&rv) += adj*ulp(&rv);
707 						word0(&rv) -= P*Exp_msk1;
712 					dval(&rv) += adj.d*ulp(&rv);
729 			if (scale && (y = word0(&rv) & Exp_mask) <= 2*P*Exp_msk1)
733 			if ((word0(&rv) & Exp_mask) <= P*Exp_msk1) {
734 				word0(&rv) += P*Exp_msk1;
735 				dval(&adj) *= ulp(&rv);
737 					dval(&rv) += adj;
739 					dval(&rv) -= adj;
740 				word0(&rv) -= P*Exp_msk1;
745 			dval(&adj) *= ulp(&rv);
747 				if (word0(&rv) == Big0 && word1(&rv) == Big1)
749 				dval(&rv) += adj.d;
752 				dval(&rv) -= adj.d;
761 			if (dsign || word1(&rv) || word0(&rv) & Bndry_mask
764 			 || (word0(&rv) & Exp_mask) <= (2*P+1)*Exp_msk1
766 			 || (word0(&rv) & Exp_mask) <= Exp_msk1
791 				if ((word0(&rv) & Bndry_mask1) == Bndry_mask1
792 				 &&  word1(&rv) == (
794 			(scale && (y = word0(&rv) & Exp_mask) <= 2*P*Exp_msk1)
799 					if (word0(&rv) == Big0 && word1(&rv) == Big1)
801 					word0(&rv) = (word0(&rv) & Exp_mask)
807 					word1(&rv) = 0;
814 			else if (!(word0(&rv) & Bndry_mask) && !word1(&rv)) {
818 				L = word0(&rv) & Exp_mask;
833 					L = word0(&rv) & Exp_mask;
837 							/* accept rv */
839 						/* rv = smallest denormal */
844 				L = (word0(&rv) & Exp_mask) - Exp_msk1;
846 				word0(&rv) = L | Bndry_mask1;
847 				word1(&rv) = 0xffffffff;
857 				if (!(word0(&rv) & Lsb1))
860 			else if (!(word1(&rv) & Lsb))
863 			if (!(word1(&rv) & LSB))
869 				dval(&rv) += sulp(&rv, scale);
871 				dval(&rv) += ulp(&rv);
876 				dval(&rv) -= sulp(&rv, scale);
878 				dval(&rv) -= ulp(&rv);
881 				if (!dval(&rv))
894 			else if (word1(&rv) || word0(&rv) & Bndry_mask) {
896 				if (word1(&rv) == Tiny1 && !word0(&rv))
930 		y = word0(&rv) & Exp_mask;
935 			dval(&rv0) = dval(&rv);
936 			word0(&rv) -= P*Exp_msk1;
937 			dval(&adj) = dval(&aadj1) * ulp(&rv);
938 			dval(&rv) += dval(&adj);
939 			if ((word0(&rv) & Exp_mask) >=
943 				word0(&rv) = Big0;
944 				word1(&rv) = Big1;
948 				word0(&rv) += P*Exp_msk1;
961 			dval(&adj) = dval(&aadj1) * ulp(&rv);
962 			dval(&rv) += dval(&adj);
965 			if ((word0(&rv) & Exp_mask) <= P*Exp_msk1) {
966 				dval(&rv0) = dval(&rv);
967 				word0(&rv) += P*Exp_msk1;
968 				dval(&adj) = dval(&aadj1) * ulp(&rv);
969 				dval(&rv) += adj;
971 				if ((word0(&rv) & Exp_mask) <  P*Exp_msk1)
973 				if ((word0(&rv) & Exp_mask) <= P*Exp_msk1)
979 					word0(&rv) = Tiny0;
980 					word1(&rv) = Tiny1;
984 					word0(&rv) -= P*Exp_msk1;
987 				dval(&adj) = dval(&aadj1) * ulp(&rv);
988 				dval(&rv) += adj;
992 			 * correctly round rv + dval(&adj) in some half-way cases.
993 			 * If rv * ulp(&rv) is denormalized (i.e.,
1003 			dval(&adj) = dval(&aadj1) * ulp(&rv);
1004 			dval(&rv) += adj;
1008 		z = word0(&rv) & Exp_mask;
1018 			if (dsign || word1(&rv) || word0(&rv) & Bndry_mask) {
1052 		dval(&rv) *= dval(&rv0);
1056 		if (!(word0(&rv) & Exp_mask))
1058 		if (word0(&rv) == 0 && word1(&rv) == 0)
1065 	if (inexact && !(word0(&rv) & Exp_mask)) {
1074 	return sign ? -dval(&rv) : dval(&rv);