diff options
Diffstat (limited to 'winsup/mingw/mingwex/gdtoa/gdtoa.c')
| -rwxr-xr-x | winsup/mingw/mingwex/gdtoa/gdtoa.c | 758 |
1 files changed, 0 insertions, 758 deletions
diff --git a/winsup/mingw/mingwex/gdtoa/gdtoa.c b/winsup/mingw/mingwex/gdtoa/gdtoa.c deleted file mode 100755 index cafb80743..000000000 --- a/winsup/mingw/mingwex/gdtoa/gdtoa.c +++ /dev/null @@ -1,758 +0,0 @@ -/**************************************************************** - -The author of this software is David M. Gay. - -Copyright (C) 1998, 1999 by Lucent Technologies -All Rights Reserved - -Permission to use, copy, modify, and distribute this software and -its documentation for any purpose and without fee is hereby -granted, provided that the above copyright notice appear in all -copies and that both that the copyright notice and this -permission notice and warranty disclaimer appear in supporting -documentation, and that the name of Lucent or any of its entities -not be used in advertising or publicity pertaining to -distribution of the software without specific, written prior -permission. - -LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, -INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. -IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY -SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES -WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER -IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, -ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF -THIS SOFTWARE. - -****************************************************************/ - -/* Please send bug reports to David M. Gay (dmg at acm dot org, - * with " at " changed at "@" and " dot " changed to "."). */ - -#include "gdtoaimp.h" - - static Bigint * -#ifdef KR_headers -bitstob(bits, nbits, bbits) ULong *bits; int nbits; int *bbits; -#else -bitstob(ULong *bits, int nbits, int *bbits) -#endif -{ - int i, k; - Bigint *b; - ULong *be, *x, *x0; - - i = ULbits; - k = 0; - while(i < nbits) { - i <<= 1; - k++; - } -#ifndef Pack_32 - if (!k) - k = 1; -#endif - b = Balloc(k); - be = bits + ((nbits - 1) >> kshift); - x = x0 = b->x; - do { - *x++ = *bits & ALL_ON; -#ifdef Pack_16 - *x++ = (*bits >> 16) & ALL_ON; -#endif - } while(++bits <= be); - i = x - x0; - while(!x0[--i]) - if (!i) { - b->wds = 0; - *bbits = 0; - goto ret; - } - b->wds = i + 1; - *bbits = i*ULbits + 32 - hi0bits(b->x[i]); - ret: - return b; - } - -/* dtoa for IEEE arithmetic (dmg): convert double to ASCII string. - * - * Inspired by "How to Print Floating-Point Numbers Accurately" by - * Guy L. Steele, Jr. and Jon L. White [Proc. ACM SIGPLAN '90, pp. 112-126]. - * - * Modifications: - * 1. Rather than iterating, we use a simple numeric overestimate - * to determine k = floor(log10(d)). We scale relevant - * quantities using O(log2(k)) rather than O(k) multiplications. - * 2. For some modes > 2 (corresponding to ecvt and fcvt), we don't - * try to generate digits strictly left to right. Instead, we - * compute with fewer bits and propagate the carry if necessary - * when rounding the final digit up. This is often faster. - * 3. Under the assumption that input will be rounded nearest, - * mode 0 renders 1e23 as 1e23 rather than 9.999999999999999e22. - * That is, we allow equality in stopping tests when the - * round-nearest rule will give the same floating-point value - * as would satisfaction of the stopping test with strict - * inequality. - * 4. We remove common factors of powers of 2 from relevant - * quantities. - * 5. When converting floating-point integers less than 1e16, - * we use floating-point arithmetic rather than resorting - * to multiple-precision integers. - * 6. When asked to produce fewer than 15 digits, we first try - * to get by with floating-point arithmetic; we resort to - * multiple-precision integer arithmetic only if we cannot - * guarantee that the floating-point calculation has given - * the correctly rounded result. For k requested digits and - * "uniformly" distributed input, the probability is - * something like 10^(k-15) that we must resort to the Long - * calculation. - */ - - char * -__gdtoa -#ifdef KR_headers - (fpi, be, bits, kindp, mode, ndigits, decpt, rve) - FPI *fpi; int be; ULong *bits; - int *kindp, mode, ndigits, *decpt; char **rve; -#else - (FPI *fpi, int be, ULong *bits, int *kindp, int mode, int ndigits, int *decpt, char **rve) -#endif -{ - /* Arguments ndigits and decpt are similar to the second and third - arguments of ecvt and fcvt; trailing zeros are suppressed from - the returned string. If not null, *rve is set to point - to the end of the return value. If d is +-Infinity or NaN, - then *decpt is set to 9999. - - mode: - 0 ==> shortest string that yields d when read in - and rounded to nearest. - 1 ==> like 0, but with Steele & White stopping rule; - e.g. with IEEE P754 arithmetic , mode 0 gives - 1e23 whereas mode 1 gives 9.999999999999999e22. - 2 ==> max(1,ndigits) significant digits. This gives a - return value similar to that of ecvt, except - that trailing zeros are suppressed. - 3 ==> through ndigits past the decimal point. This - gives a return value similar to that from fcvt, - except that trailing zeros are suppressed, and - ndigits can be negative. - 4-9 should give the same return values as 2-3, i.e., - 4 <= mode <= 9 ==> same return as mode - 2 + (mode & 1). These modes are mainly for - debugging; often they run slower but sometimes - faster than modes 2-3. - 4,5,8,9 ==> left-to-right digit generation. - 6-9 ==> don't try fast floating-point estimate - (if applicable). - - Values of mode other than 0-9 are treated as mode 0. - - Sufficient space is allocated to the return value - to hold the suppressed trailing zeros. - */ - - int bbits, b2, b5, be0, dig, i, ieps, ilim = 0, ilim0, ilim1 = 0, inex; - int j, j1, k, k0, k_check, kind, leftright, m2, m5, nbits; - int rdir, s2, s5, spec_case, try_quick; - Long L; - Bigint *b, *b1, *delta, *mlo, *mhi, *mhi1, *S; - double d, d2, ds, eps; - char *s, *s0; - -#ifndef MULTIPLE_THREADS - if (dtoa_result) { - __freedtoa(dtoa_result); - dtoa_result = 0; - } -#endif - inex = 0; - kind = *kindp &= ~STRTOG_Inexact; - switch(kind & STRTOG_Retmask) { - case STRTOG_Zero: - goto ret_zero; - case STRTOG_Normal: - case STRTOG_Denormal: - break; - case STRTOG_Infinite: - *decpt = -32768; - return nrv_alloc("Infinity", rve, 8); - case STRTOG_NaN: - *decpt = -32768; - return nrv_alloc("NaN", rve, 3); - default: - return 0; - } - b = bitstob(bits, nbits = fpi->nbits, &bbits); - be0 = be; - if ( (i = trailz(b)) !=0) { - rshift(b, i); - be += i; - bbits -= i; - } - if (!b->wds) { - Bfree(b); - ret_zero: - *decpt = 1; - return nrv_alloc("0", rve, 1); - } - - dval(d) = b2d(b, &i); - i = be + bbits - 1; - word0(d) &= Frac_mask1; - word0(d) |= Exp_11; -#ifdef IBM - if ( (j = 11 - hi0bits(word0(d) & Frac_mask)) !=0) - dval(d) /= 1 << j; -#endif - - /* log(x) ~=~ log(1.5) + (x-1.5)/1.5 - * log10(x) = log(x) / log(10) - * ~=~ log(1.5)/log(10) + (x-1.5)/(1.5*log(10)) - * log10(d) = (i-Bias)*log(2)/log(10) + log10(d2) - * - * This suggests computing an approximation k to log10(d) by - * - * k = (i - Bias)*0.301029995663981 - * + ( (d2-1.5)*0.289529654602168 + 0.176091259055681 ); - * - * We want k to be too large rather than too small. - * The error in the first-order Taylor series approximation - * is in our favor, so we just round up the constant enough - * to compensate for any error in the multiplication of - * (i - Bias) by 0.301029995663981; since |i - Bias| <= 1077, - * and 1077 * 0.30103 * 2^-52 ~=~ 7.2e-14, - * adding 1e-13 to the constant term more than suffices. - * Hence we adjust the constant term to 0.1760912590558. - * (We could get a more accurate k by invoking log10, - * but this is probably not worthwhile.) - */ -#ifdef IBM - i <<= 2; - i += j; -#endif - ds = (dval(d)-1.5)*0.289529654602168 + 0.1760912590558 + i*0.301029995663981; - - /* correct assumption about exponent range */ - if ((j = i) < 0) - j = -j; - if ((j -= 1077) > 0) - ds += j * 7e-17; - - k = (int)ds; - if (ds < 0. && ds != k) - k--; /* want k = floor(ds) */ - k_check = 1; -#ifdef IBM - j = be + bbits - 1; - if ( (j1 = j & 3) !=0) - dval(d) *= 1 << j1; - word0(d) += j << Exp_shift - 2 & Exp_mask; -#else - word0(d) += (be + bbits - 1) << Exp_shift; -#endif - if (k >= 0 && k <= Ten_pmax) { - if (dval(d) < tens[k]) - k--; - k_check = 0; - } - j = bbits - i - 1; - if (j >= 0) { - b2 = 0; - s2 = j; - } - else { - b2 = -j; - s2 = 0; - } - if (k >= 0) { - b5 = 0; - s5 = k; - s2 += k; - } - else { - b2 -= k; - b5 = -k; - s5 = 0; - } - if (mode < 0 || mode > 9) - mode = 0; - try_quick = 1; - if (mode > 5) { - mode -= 4; - try_quick = 0; - } - leftright = 1; - switch(mode) { - case 0: - case 1: - ilim = ilim1 = -1; - i = (int)(nbits * .30103) + 3; - ndigits = 0; - break; - case 2: - leftright = 0; - /* no break */ - case 4: - if (ndigits <= 0) - ndigits = 1; - ilim = ilim1 = i = ndigits; - break; - case 3: - leftright = 0; - /* no break */ - case 5: - i = ndigits + k + 1; - ilim = i; - ilim1 = i - 1; - if (i <= 0) - i = 1; - } - s = s0 = rv_alloc(i); - - if ( (rdir = fpi->rounding - 1) !=0) { - if (rdir < 0) - rdir = 2; - if (kind & STRTOG_Neg) - rdir = 3 - rdir; - } - - /* Now rdir = 0 ==> round near, 1 ==> round up, 2 ==> round down. */ - - if (ilim >= 0 && ilim <= Quick_max && try_quick && !rdir -#ifndef IMPRECISE_INEXACT - && k == 0 -#endif - ) { - - /* Try to get by with floating-point arithmetic. */ - - i = 0; - d2 = dval(d); -#ifdef IBM - if ( (j = 11 - hi0bits(word0(d) & Frac_mask)) !=0) - dval(d) /= 1 << j; -#endif - k0 = k; - ilim0 = ilim; - ieps = 2; /* conservative */ - if (k > 0) { - ds = tens[k&0xf]; - j = k >> 4; - if (j & Bletch) { - /* prevent overflows */ - j &= Bletch - 1; - dval(d) /= bigtens[n_bigtens-1]; - ieps++; - } - for(; j; j >>= 1, i++) - if (j & 1) { - ieps++; - ds *= bigtens[i]; - } - } - else { - ds = 1.; - if ( (j1 = -k) !=0) { - dval(d) *= tens[j1 & 0xf]; - for(j = j1 >> 4; j; j >>= 1, i++) - if (j & 1) { - ieps++; - dval(d) *= bigtens[i]; - } - } - } - if (k_check && dval(d) < 1. && ilim > 0) { - if (ilim1 <= 0) - goto fast_failed; - ilim = ilim1; - k--; - dval(d) *= 10.; - ieps++; - } - dval(eps) = ieps*dval(d) + 7.; - word0(eps) -= (P-1)*Exp_msk1; - if (ilim == 0) { - S = mhi = 0; - dval(d) -= 5.; - if (dval(d) > dval(eps)) - goto one_digit; - if (dval(d) < -dval(eps)) - goto no_digits; - goto fast_failed; - } -#ifndef No_leftright - if (leftright) { - /* Use Steele & White method of only - * generating digits needed. - */ - dval(eps) = ds*0.5/tens[ilim-1] - dval(eps); - for(i = 0;;) { - L = (Long)(dval(d)/ds); - dval(d) -= L*ds; - *s++ = '0' + (int)L; - if (dval(d) < dval(eps)) { - if (dval(d)) - inex = STRTOG_Inexlo; - goto ret1; - } - if (ds - dval(d) < dval(eps)) - goto bump_up; - if (++i >= ilim) - break; - dval(eps) *= 10.; - dval(d) *= 10.; - } - } - else { -#endif - /* Generate ilim digits, then fix them up. */ - dval(eps) *= tens[ilim-1]; - for(i = 1;; i++, dval(d) *= 10.) { - if ( (L = (Long)(dval(d)/ds)) !=0) - dval(d) -= L*ds; - *s++ = '0' + (int)L; - if (i == ilim) { - ds *= 0.5; - if (dval(d) > ds + dval(eps)) - goto bump_up; - else if (dval(d) < ds - dval(eps)) { - while(*--s == '0'){} - s++; - if (dval(d)) - inex = STRTOG_Inexlo; - goto ret1; - } - break; - } - } -#ifndef No_leftright - } -#endif - fast_failed: - s = s0; - dval(d) = d2; - k = k0; - ilim = ilim0; - } - - /* Do we have a "small" integer? */ - - if (be >= 0 && k <= Int_max) { - /* Yes. */ - ds = tens[k]; - if (ndigits < 0 && ilim <= 0) { - S = mhi = 0; - if (ilim < 0 || dval(d) <= 5*ds) - goto no_digits; - goto one_digit; - } - for(i = 1;; i++, dval(d) *= 10.) { - L = dval(d) / ds; - dval(d) -= L*ds; -#ifdef Check_FLT_ROUNDS - /* If FLT_ROUNDS == 2, L will usually be high by 1 */ - if (dval(d) < 0) { - L--; - dval(d) += ds; - } -#endif - *s++ = '0' + (int)L; - if (dval(d) == 0.) - break; - if (i == ilim) { - if (rdir) { - if (rdir == 1) - goto bump_up; - inex = STRTOG_Inexlo; - goto ret1; - } - dval(d) += dval(d); - if (dval(d) > ds || (dval(d) == ds && L & 1)) { - bump_up: - inex = STRTOG_Inexhi; - while(*--s == '9') - if (s == s0) { - k++; - *s = '0'; - break; - } - ++*s++; - } - else - inex = STRTOG_Inexlo; - break; - } - } - goto ret1; - } - - m2 = b2; - m5 = b5; - mhi = mlo = 0; - if (leftright) { - if (mode < 2) { - i = nbits - bbits; - if (be - i++ < fpi->emin) - /* denormal */ - i = be - fpi->emin + 1; - } - else { - j = ilim - 1; - if (m5 >= j) - m5 -= j; - else { - s5 += j -= m5; - b5 += j; - m5 = 0; - } - if ((i = ilim) < 0) { - m2 -= i; - i = 0; - } - } - b2 += i; - s2 += i; - mhi = i2b(1); - } - if (m2 > 0 && s2 > 0) { - i = m2 < s2 ? m2 : s2; - b2 -= i; - m2 -= i; - s2 -= i; - } - if (b5 > 0) { - if (leftright) { - if (m5 > 0) { - mhi = pow5mult(mhi, m5); - b1 = mult(mhi, b); - Bfree(b); - b = b1; - } - if ( (j = b5 - m5) !=0) - b = pow5mult(b, j); - } - else - b = pow5mult(b, b5); - } - S = i2b(1); - if (s5 > 0) - S = pow5mult(S, s5); - - /* Check for special case that d is a normalized power of 2. */ - - spec_case = 0; - if (mode < 2) { - if (bbits == 1 && be0 > fpi->emin + 1) { - /* The special case */ - b2++; - s2++; - spec_case = 1; - } - } - - /* Arrange for convenient computation of quotients: - * shift left if necessary so divisor has 4 leading 0 bits. - * - * Perhaps we should just compute leading 28 bits of S once - * and for all and pass them and a shift to quorem, so it - * can do shifts and ors to compute the numerator for q. - */ -#ifdef Pack_32 - if ( (i = ((s5 ? 32 - hi0bits(S->x[S->wds-1]) : 1) + s2) & 0x1f) !=0) - i = 32 - i; -#else - if ( (i = ((s5 ? 32 - hi0bits(S->x[S->wds-1]) : 1) + s2) & 0xf) !=0) - i = 16 - i; -#endif - if (i > 4) { - i -= 4; - b2 += i; - m2 += i; - s2 += i; - } - else if (i < 4) { - i += 28; - b2 += i; - m2 += i; - s2 += i; - } - if (b2 > 0) - b = lshift(b, b2); - if (s2 > 0) - S = lshift(S, s2); - if (k_check) { - if (cmp(b,S) < 0) { - k--; - b = multadd(b, 10, 0); /* we botched the k estimate */ - if (leftright) - mhi = multadd(mhi, 10, 0); - ilim = ilim1; - } - } - if (ilim <= 0 && mode > 2) { - if (ilim < 0 || cmp(b,S = multadd(S,5,0)) <= 0) { - /* no digits, fcvt style */ - no_digits: - k = -1 - ndigits; - inex = STRTOG_Inexlo; - goto ret; - } - one_digit: - inex = STRTOG_Inexhi; - *s++ = '1'; - k++; - goto ret; - } - if (leftright) { - if (m2 > 0) - mhi = lshift(mhi, m2); - - /* Compute mlo -- check for special case - * that d is a normalized power of 2. - */ - - mlo = mhi; - if (spec_case) { - mhi = Balloc(mhi->k); - Bcopy(mhi, mlo); - mhi = lshift(mhi, 1); - } - - for(i = 1;;i++) { - dig = quorem(b,S) + '0'; - /* Do we yet have the shortest decimal string - * that will round to d? - */ - j = cmp(b, mlo); - delta = diff(S, mhi); - j1 = delta->sign ? 1 : cmp(b, delta); - Bfree(delta); -#ifndef ROUND_BIASED - if (j1 == 0 && !mode && !(bits[0] & 1) && !rdir) { - if (dig == '9') - goto round_9_up; - if (j <= 0) { - if (b->wds > 1 || b->x[0]) - inex = STRTOG_Inexlo; - } - else { - dig++; - inex = STRTOG_Inexhi; - } - *s++ = dig; - goto ret; - } -#endif - if (j < 0 || (j == 0 && !mode -#ifndef ROUND_BIASED - && !(bits[0] & 1) -#endif - )) { - if (rdir && (b->wds > 1 || b->x[0])) { - if (rdir == 2) { - inex = STRTOG_Inexlo; - goto accept; - } - while (cmp(S,mhi) > 0) { - *s++ = dig; - mhi1 = multadd(mhi, 10, 0); - if (mlo == mhi) - mlo = mhi1; - mhi = mhi1; - b = multadd(b, 10, 0); - dig = quorem(b,S) + '0'; - } - if (dig++ == '9') - goto round_9_up; - inex = STRTOG_Inexhi; - goto accept; - } - if (j1 > 0) { - b = lshift(b, 1); - j1 = cmp(b, S); - if ((j1 > 0 || (j1 == 0 && dig & 1)) - && dig++ == '9') - goto round_9_up; - inex = STRTOG_Inexhi; - } - if (b->wds > 1 || b->x[0]) - inex = STRTOG_Inexlo; - accept: - *s++ = dig; - goto ret; - } - if (j1 > 0 && rdir != 2) { - if (dig == '9') { /* possible if i == 1 */ - round_9_up: - *s++ = '9'; - inex = STRTOG_Inexhi; - goto roundoff; - } - inex = STRTOG_Inexhi; - *s++ = dig + 1; - goto ret; - } - *s++ = dig; - if (i == ilim) - break; - b = multadd(b, 10, 0); - if (mlo == mhi) - mlo = mhi = multadd(mhi, 10, 0); - else { - mlo = multadd(mlo, 10, 0); - mhi = multadd(mhi, 10, 0); - } - } - } - else - for(i = 1;; i++) { - *s++ = dig = quorem(b,S) + '0'; - if (i >= ilim) - break; - b = multadd(b, 10, 0); - } - - /* Round off last digit */ - - if (rdir) { - if (rdir == 2 || (b->wds <= 1 && !b->x[0])) - goto chopzeros; - goto roundoff; - } - b = lshift(b, 1); - j = cmp(b, S); - if (j > 0 || (j == 0 && dig & 1)) { - roundoff: - inex = STRTOG_Inexhi; - while(*--s == '9') - if (s == s0) { - k++; - *s++ = '1'; - goto ret; - } - ++*s++; - } - else { - chopzeros: - if (b->wds > 1 || b->x[0]) - inex = STRTOG_Inexlo; - while(*--s == '0'){} - s++; - } - ret: - Bfree(S); - if (mhi) { - if (mlo && mlo != mhi) - Bfree(mlo); - Bfree(mhi); - } - ret1: - Bfree(b); - *s = 0; - *decpt = k + 1; - if (rve) - *rve = s; - *kindp |= inex; - return s0; - } |