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-rw-r--r--examples/redis-unstable/deps/fpconv/fpconv_dtoa.c373
1 files changed, 0 insertions, 373 deletions
diff --git a/examples/redis-unstable/deps/fpconv/fpconv_dtoa.c b/examples/redis-unstable/deps/fpconv/fpconv_dtoa.c
deleted file mode 100644
index ad2f2de..0000000
--- a/examples/redis-unstable/deps/fpconv/fpconv_dtoa.c
+++ /dev/null
@@ -1,373 +0,0 @@
-/* fpconv_dtoa.c -- floating point conversion utilities.
- *
- * Fast and accurate double to string conversion based on Florian Loitsch's
- * Grisu-algorithm[1].
- *
- * [1] https://www.cs.tufts.edu/~nr/cs257/archive/florian-loitsch/printf.pdf
- * ----------------------------------------------------------------------------
- *
- * Copyright (c) 2013-2019, night-shift <as.smljk at gmail dot com>
- * Copyright (c) 2009, Florian Loitsch < florian.loitsch at inria dot fr >
- * All rights reserved.
- *
- * Boost Software License - Version 1.0 - August 17th, 2003
- *
- * Permission is hereby granted, free of charge, to any person or organization
- * obtaining a copy of the software and accompanying documentation covered by
- * this license (the "Software") to use, reproduce, display, distribute,
- * execute, and transmit the Software, and to prepare derivative works of the
- * Software, and to permit third-parties to whom the Software is furnished to
- * do so, all subject to the following:
- *
- * The copyright notices in the Software and this entire statement, including
- * the above license grant, this restriction and the following disclaimer,
- * must be included in all copies of the Software, in whole or in part, and
- * all derivative works of the Software, unless such copies or derivative
- * works are solely in the form of machine-executable object code generated by
- * a source language processor.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
- * SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
- * FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
- * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
- * DEALINGS IN THE SOFTWARE.
- */
-
-#include "fpconv_dtoa.h"
-
-#include "fpconv_powers.h"
-
-#include <stdbool.h>
-#include <string.h>
-
-#define fracmask 0x000FFFFFFFFFFFFFU
-#define expmask 0x7FF0000000000000U
-#define hiddenbit 0x0010000000000000U
-#define signmask 0x8000000000000000U
-#define expbias (1023 + 52)
-
-#define absv(n) ((n) < 0 ? -(n) : (n))
-#define minv(a, b) ((a) < (b) ? (a) : (b))
-
-static uint64_t tens[] = { 10000000000000000000U,
- 1000000000000000000U,
- 100000000000000000U,
- 10000000000000000U,
- 1000000000000000U,
- 100000000000000U,
- 10000000000000U,
- 1000000000000U,
- 100000000000U,
- 10000000000U,
- 1000000000U,
- 100000000U,
- 10000000U,
- 1000000U,
- 100000U,
- 10000U,
- 1000U,
- 100U,
- 10U,
- 1U };
-
-static inline uint64_t get_dbits(double d) {
- union
- {
- double dbl;
- uint64_t i;
- } dbl_bits = { d };
-
- return dbl_bits.i;
-}
-
-static Fp build_fp(double d) {
- uint64_t bits = get_dbits(d);
-
- Fp fp;
- fp.frac = bits & fracmask;
- fp.exp = (bits & expmask) >> 52;
-
- if (fp.exp) {
- fp.frac += hiddenbit;
- fp.exp -= expbias;
-
- } else {
- fp.exp = -expbias + 1;
- }
-
- return fp;
-}
-
-static void normalize(Fp *fp) {
- while ((fp->frac & hiddenbit) == 0) {
- fp->frac <<= 1;
- fp->exp--;
- }
-
- int shift = 64 - 52 - 1;
- fp->frac <<= shift;
- fp->exp -= shift;
-}
-
-static void get_normalized_boundaries(Fp *fp, Fp *lower, Fp *upper) {
- upper->frac = (fp->frac << 1) + 1;
- upper->exp = fp->exp - 1;
-
- while ((upper->frac & (hiddenbit << 1)) == 0) {
- upper->frac <<= 1;
- upper->exp--;
- }
-
- int u_shift = 64 - 52 - 2;
-
- upper->frac <<= u_shift;
- upper->exp = upper->exp - u_shift;
-
- int l_shift = fp->frac == hiddenbit ? 2 : 1;
-
- lower->frac = (fp->frac << l_shift) - 1;
- lower->exp = fp->exp - l_shift;
-
- lower->frac <<= lower->exp - upper->exp;
- lower->exp = upper->exp;
-}
-
-static Fp multiply(Fp *a, Fp *b) {
- const uint64_t lomask = 0x00000000FFFFFFFF;
-
- uint64_t ah_bl = (a->frac >> 32) * (b->frac & lomask);
- uint64_t al_bh = (a->frac & lomask) * (b->frac >> 32);
- uint64_t al_bl = (a->frac & lomask) * (b->frac & lomask);
- uint64_t ah_bh = (a->frac >> 32) * (b->frac >> 32);
-
- uint64_t tmp = (ah_bl & lomask) + (al_bh & lomask) + (al_bl >> 32);
- /* round up */
- tmp += 1U << 31;
-
- Fp fp = { ah_bh + (ah_bl >> 32) + (al_bh >> 32) + (tmp >> 32), a->exp + b->exp + 64 };
-
- return fp;
-}
-
-static void round_digit(char *digits,
- int ndigits,
- uint64_t delta,
- uint64_t rem,
- uint64_t kappa,
- uint64_t frac) {
- while (rem < frac && delta - rem >= kappa &&
- (rem + kappa < frac || frac - rem > rem + kappa - frac)) {
- digits[ndigits - 1]--;
- rem += kappa;
- }
-}
-
-static int generate_digits(Fp *fp, Fp *upper, Fp *lower, char *digits, int *K) {
- uint64_t wfrac = upper->frac - fp->frac;
- uint64_t delta = upper->frac - lower->frac;
-
- Fp one;
- one.frac = 1ULL << -upper->exp;
- one.exp = upper->exp;
-
- uint64_t part1 = upper->frac >> -one.exp;
- uint64_t part2 = upper->frac & (one.frac - 1);
-
- int idx = 0, kappa = 10;
- uint64_t *divp;
- /* 1000000000 */
- for (divp = tens + 10; kappa > 0; divp++) {
- uint64_t div = *divp;
- unsigned digit = part1 / div;
-
- if (digit || idx) {
- digits[idx++] = digit + '0';
- }
-
- part1 -= digit * div;
- kappa--;
-
- uint64_t tmp = (part1 << -one.exp) + part2;
- if (tmp <= delta) {
- *K += kappa;
- round_digit(digits, idx, delta, tmp, div << -one.exp, wfrac);
-
- return idx;
- }
- }
-
- /* 10 */
- uint64_t *unit = tens + 18;
-
- while (true) {
- part2 *= 10;
- delta *= 10;
- kappa--;
-
- unsigned digit = part2 >> -one.exp;
- if (digit || idx) {
- digits[idx++] = digit + '0';
- }
-
- part2 &= one.frac - 1;
- if (part2 < delta) {
- *K += kappa;
- round_digit(digits, idx, delta, part2, one.frac, wfrac * *unit);
-
- return idx;
- }
-
- unit--;
- }
-}
-
-static int grisu2(double d, char *digits, int *K) {
- Fp w = build_fp(d);
-
- Fp lower, upper;
- get_normalized_boundaries(&w, &lower, &upper);
-
- normalize(&w);
-
- int k;
- Fp cp = find_cachedpow10(upper.exp, &k);
-
- w = multiply(&w, &cp);
- upper = multiply(&upper, &cp);
- lower = multiply(&lower, &cp);
-
- lower.frac++;
- upper.frac--;
-
- *K = -k;
-
- return generate_digits(&w, &upper, &lower, digits, K);
-}
-
-static int emit_digits(char *digits, int ndigits, char *dest, int K, bool neg) {
- int exp = absv(K + ndigits - 1);
-
- /* write plain integer */
- if (K >= 0 && (exp < (ndigits + 7))) {
- memcpy(dest, digits, ndigits);
- memset(dest + ndigits, '0', K);
-
- return ndigits + K;
- }
-
- /* write decimal w/o scientific notation */
- if (K < 0 && (K > -7 || exp < 4)) {
- int offset = ndigits - absv(K);
- /* fp < 1.0 -> write leading zero */
- if (offset <= 0) {
- offset = -offset;
- dest[0] = '0';
- dest[1] = '.';
- memset(dest + 2, '0', offset);
- memcpy(dest + offset + 2, digits, ndigits);
-
- return ndigits + 2 + offset;
-
- /* fp > 1.0 */
- } else {
- memcpy(dest, digits, offset);
- dest[offset] = '.';
- memcpy(dest + offset + 1, digits + offset, ndigits - offset);
-
- return ndigits + 1;
- }
- }
-
- /* write decimal w/ scientific notation */
- ndigits = minv(ndigits, 18 - neg);
-
- int idx = 0;
- dest[idx++] = digits[0];
-
- if (ndigits > 1) {
- dest[idx++] = '.';
- memcpy(dest + idx, digits + 1, ndigits - 1);
- idx += ndigits - 1;
- }
-
- dest[idx++] = 'e';
-
- char sign = K + ndigits - 1 < 0 ? '-' : '+';
- dest[idx++] = sign;
-
- int cent = 0;
-
- if (exp > 99) {
- cent = exp / 100;
- dest[idx++] = cent + '0';
- exp -= cent * 100;
- }
- if (exp > 9) {
- int dec = exp / 10;
- dest[idx++] = dec + '0';
- exp -= dec * 10;
-
- } else if (cent) {
- dest[idx++] = '0';
- }
-
- dest[idx++] = exp % 10 + '0';
-
- return idx;
-}
-
-static int filter_special(double fp, char *dest) {
- if (fp == 0.0) {
- dest[0] = '0';
- return 1;
- }
-
- uint64_t bits = get_dbits(fp);
-
- bool nan = (bits & expmask) == expmask;
-
- if (!nan) {
- return 0;
- }
-
- if (bits & fracmask) {
- dest[0] = 'n';
- dest[1] = 'a';
- dest[2] = 'n';
-
- } else {
- dest[0] = 'i';
- dest[1] = 'n';
- dest[2] = 'f';
- }
-
- return 3;
-}
-
-int fpconv_dtoa(double d, char dest[24]) {
- char digits[18];
-
- int str_len = 0;
- bool neg = false;
-
- if (get_dbits(d) & signmask) {
- dest[0] = '-';
- str_len++;
- neg = true;
- }
-
- int spec = filter_special(d, dest + str_len);
-
- if (spec) {
- return str_len + spec;
- }
-
- int K = 0;
- int ndigits = grisu2(d, digits, &K);
-
- str_len += emit_digits(digits, ndigits, dest + str_len, K, neg);
-
- return str_len;
-}
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