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diff --git a/third_party/rust/dtoa/src/dtoa.rs b/third_party/rust/dtoa/src/dtoa.rs
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+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+//
+// ---
+//
+// The C++ implementation preserved here in comments is licensed as follows:
+//
+// Tencent is pleased to support the open source community by making RapidJSON
+// available.
+//
+// Copyright (C) 2015 THL A29 Limited, a Tencent company, and Milo Yip. All
+// rights reserved.
+//
+// Licensed under the MIT License (the "License"); you may not use this file
+// except in compliance with the License. You may obtain a copy of the License
+// at
+//
+// http://opensource.org/licenses/MIT
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+
+#[doc(hidden)]
+#[macro_export]
+macro_rules! dtoa {(
+ floating_type: $fty:ty,
+ significand_type: $sigty:ty,
+ exponent_type: $expty:ty,
+ $($diyfp_param:ident: $diyfp_value:tt,)*
+) => {
+
+diyfp! {
+ floating_type: $fty,
+ significand_type: $sigty,
+ exponent_type: $expty,
+ $($diyfp_param: $diyfp_value,)*
+};
+
+/*
+inline void GrisuRound(char* buffer, int len, uint64_t delta, uint64_t rest, uint64_t ten_kappa, uint64_t wp_w) {
+ while (rest < wp_w && delta - rest >= ten_kappa &&
+ (rest + ten_kappa < wp_w || /// closer
+ wp_w - rest > rest + ten_kappa - wp_w)) {
+ buffer[len - 1]--;
+ rest += ten_kappa;
+ }
+}
+*/
+
+#[inline]
+unsafe fn grisu_round(buffer: *mut u8, len: isize, delta: $sigty, mut rest: $sigty, ten_kappa: $sigty, wp_w: $sigty) {
+ while rest < wp_w && delta - rest >= ten_kappa &&
+ (rest + ten_kappa < wp_w || // closer
+ wp_w - rest > rest + ten_kappa - wp_w) {
+ *buffer.offset(len - 1) -= 1;
+ rest += ten_kappa;
+ }
+}
+
+/*
+inline unsigned CountDecimalDigit32(uint32_t n) {
+ // Simple pure C++ implementation was faster than __builtin_clz version in this situation.
+ if (n < 10) return 1;
+ if (n < 100) return 2;
+ if (n < 1000) return 3;
+ if (n < 10000) return 4;
+ if (n < 100000) return 5;
+ if (n < 1000000) return 6;
+ if (n < 10000000) return 7;
+ if (n < 100000000) return 8;
+ // Will not reach 10 digits in DigitGen()
+ //if (n < 1000000000) return 9;
+ //return 10;
+ return 9;
+}
+*/
+
+#[inline]
+fn count_decimal_digit32(n: u32) -> usize {
+ if n < 10 { 1 }
+ else if n < 100 { 2 }
+ else if n < 1000 { 3 }
+ else if n < 10000 { 4 }
+ else if n < 100000 { 5 }
+ else if n < 1000000 { 6 }
+ else if n < 10000000 { 7 }
+ else if n < 100000000 { 8 }
+ // Will not reach 10 digits in digit_gen()
+ else { 9 }
+}
+
+/*
+inline void DigitGen(const DiyFp& W, const DiyFp& Mp, uint64_t delta, char* buffer, int* len, int* K) {
+ static const uint32_t kPow10[] = { 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000 };
+ const DiyFp one(uint64_t(1) << -Mp.e, Mp.e);
+ const DiyFp wp_w = Mp - W;
+ uint32_t p1 = static_cast<uint32_t>(Mp.f >> -one.e);
+ uint64_t p2 = Mp.f & (one.f - 1);
+ unsigned kappa = CountDecimalDigit32(p1); // kappa in [0, 9]
+ *len = 0;
+*/
+
+// Returns length and k.
+#[inline]
+unsafe fn digit_gen(w: DiyFp, mp: DiyFp, mut delta: $sigty, buffer: *mut u8, mut k: isize) -> (isize, isize) {
+ static POW10: [$sigty; 10] = [ 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000 ];
+ let one = DiyFp::new(1 << -mp.e, mp.e);
+ let wp_w = mp - w;
+ let mut p1 = (mp.f >> -one.e) as u32;
+ let mut p2 = mp.f & (one.f - 1);
+ let mut kappa = count_decimal_digit32(p1); // kappa in [0, 9]
+ let mut len = 0;
+
+ /*
+ while (kappa > 0) {
+ uint32_t d = 0;
+ switch (kappa) {
+ case 9: d = p1 / 100000000; p1 %= 100000000; break;
+ case 8: d = p1 / 10000000; p1 %= 10000000; break;
+ case 7: d = p1 / 1000000; p1 %= 1000000; break;
+ case 6: d = p1 / 100000; p1 %= 100000; break;
+ case 5: d = p1 / 10000; p1 %= 10000; break;
+ case 4: d = p1 / 1000; p1 %= 1000; break;
+ case 3: d = p1 / 100; p1 %= 100; break;
+ case 2: d = p1 / 10; p1 %= 10; break;
+ case 1: d = p1; p1 = 0; break;
+ default:;
+ }
+ if (d || *len)
+ buffer[(*len)++] = static_cast<char>('0' + static_cast<char>(d));
+ kappa--;
+ uint64_t tmp = (static_cast<uint64_t>(p1) << -one.e) + p2;
+ if (tmp <= delta) {
+ *K += kappa;
+ GrisuRound(buffer, *len, delta, tmp, static_cast<uint64_t>(kPow10[kappa]) << -one.e, wp_w.f);
+ return;
+ }
+ }
+ */
+ while kappa > 0 {
+ let mut d = 0u32;
+ match kappa {
+ 9 => { d = p1 / 100000000; p1 %= 100000000; }
+ 8 => { d = p1 / 10000000; p1 %= 10000000; }
+ 7 => { d = p1 / 1000000; p1 %= 1000000; }
+ 6 => { d = p1 / 100000; p1 %= 100000; }
+ 5 => { d = p1 / 10000; p1 %= 10000; }
+ 4 => { d = p1 / 1000; p1 %= 1000; }
+ 3 => { d = p1 / 100; p1 %= 100; }
+ 2 => { d = p1 / 10; p1 %= 10; }
+ 1 => { d = p1; p1 = 0; }
+ _ => {}
+ }
+ if d != 0 || len != 0 {
+ *buffer.offset(len) = b'0' + d as u8;
+ len += 1;
+ }
+ kappa -= 1;
+ let tmp = (p1 as $sigty << -one.e) + p2;
+ if tmp <= delta {
+ k += kappa as isize;
+ grisu_round(buffer, len, delta, tmp, POW10[kappa] << -one.e, wp_w.f);
+ return (len, k);
+ }
+ }
+
+ // kappa = 0
+ /*
+ for (;;) {
+ p2 *= 10;
+ delta *= 10;
+ char d = static_cast<char>(p2 >> -one.e);
+ if (d || *len)
+ buffer[(*len)++] = static_cast<char>('0' + d);
+ p2 &= one.f - 1;
+ kappa--;
+ if (p2 < delta) {
+ *K += kappa;
+ int index = -static_cast<int>(kappa);
+ GrisuRound(buffer, *len, delta, p2, one.f, wp_w.f * (index < 9 ? kPow10[-static_cast<int>(kappa)] : 0));
+ return;
+ }
+ }
+ */
+ loop {
+ p2 *= 10;
+ delta *= 10;
+ let d = (p2 >> -one.e) as u8;
+ if d != 0 || len != 0 {
+ *buffer.offset(len) = b'0' + d;
+ len += 1;
+ }
+ p2 &= one.f - 1;
+ kappa = kappa.wrapping_sub(1);
+ if p2 < delta {
+ k += kappa as isize;
+ let index = -(kappa as isize);
+ grisu_round(buffer, len, delta, p2, one.f, wp_w.f * if index < 9 { POW10[-(kappa as isize) as usize] } else { 0 });
+ return (len, k);
+ }
+ }
+}
+
+/*
+inline void Grisu2(double value, char* buffer, int* length, int* K) {
+ const DiyFp v(value);
+ DiyFp w_m, w_p;
+ v.NormalizedBoundaries(&w_m, &w_p);
+
+ const DiyFp c_mk = GetCachedPower(w_p.e, K);
+ const DiyFp W = v.Normalize() * c_mk;
+ DiyFp Wp = w_p * c_mk;
+ DiyFp Wm = w_m * c_mk;
+ Wm.f++;
+ Wp.f--;
+ DigitGen(W, Wp, Wp.f - Wm.f, buffer, length, K);
+}
+*/
+
+// Returns length and k.
+#[inline]
+unsafe fn grisu2(value: $fty, buffer: *mut u8) -> (isize, isize) {
+ let v = DiyFp::from(value);
+ let (w_m, w_p) = v.normalized_boundaries();
+
+ let (c_mk, k) = get_cached_power(w_p.e);
+ let w = v.normalize() * c_mk;
+ let mut wp = w_p * c_mk;
+ let mut wm = w_m * c_mk;
+ wm.f += 1;
+ wp.f -= 1;
+ digit_gen(w, wp, wp.f - wm.f, buffer, k)
+}
+
+/*
+inline char* WriteExponent(int K, char* buffer) {
+ if (K < 0) {
+ *buffer++ = '-';
+ K = -K;
+ }
+
+ if (K >= 100) {
+ *buffer++ = static_cast<char>('0' + static_cast<char>(K / 100));
+ K %= 100;
+ const char* d = GetDigitsLut() + K * 2;
+ *buffer++ = d[0];
+ *buffer++ = d[1];
+ }
+ else if (K >= 10) {
+ const char* d = GetDigitsLut() + K * 2;
+ *buffer++ = d[0];
+ *buffer++ = d[1];
+ }
+ else
+ *buffer++ = static_cast<char>('0' + static_cast<char>(K));
+
+ return buffer;
+}
+*/
+
+#[inline]
+unsafe fn write_exponent(mut k: isize, mut buffer: *mut u8) -> *mut u8 {
+ if k < 0 {
+ *buffer = b'-';
+ buffer = buffer.offset(1);
+ k = -k;
+ }
+
+ if k >= 100 {
+ *buffer = b'0' + (k / 100) as u8;
+ k %= 100;
+ let d = DEC_DIGITS_LUT.get_unchecked(k as usize * 2);
+ ptr::copy_nonoverlapping(d, buffer.offset(1), 2);
+ buffer.offset(3)
+ } else if k >= 10 {
+ let d = DEC_DIGITS_LUT.get_unchecked(k as usize * 2);
+ ptr::copy_nonoverlapping(d, buffer, 2);
+ buffer.offset(2)
+ } else {
+ *buffer = b'0' + k as u8;
+ buffer.offset(1)
+ }
+}
+
+/*
+inline char* Prettify(char* buffer, int length, int k, int maxDecimalPlaces) {
+ const int kk = length + k; // 10^(kk-1) <= v < 10^kk
+*/
+
+#[inline]
+unsafe fn prettify(buffer: *mut u8, length: isize, k: isize) -> *mut u8 {
+ let kk = length + k; // 10^(kk-1) <= v < 10^kk
+
+ /*
+ if (0 <= k && kk <= 21) {
+ // 1234e7 -> 12340000000
+ for (int i = length; i < kk; i++)
+ buffer[i] = '0';
+ buffer[kk] = '.';
+ buffer[kk + 1] = '0';
+ return &buffer[kk + 2];
+ }
+ */
+ if 0 <= k && kk <= 21 {
+ // 1234e7 -> 12340000000
+ for i in length..kk {
+ *buffer.offset(i) = b'0';
+ }
+ *buffer.offset(kk) = b'.';
+ *buffer.offset(kk + 1) = b'0';
+ buffer.offset(kk + 2)
+ }
+
+ /*
+ else if (0 < kk && kk <= 21) {
+ // 1234e-2 -> 12.34
+ std::memmove(&buffer[kk + 1], &buffer[kk], static_cast<size_t>(length - kk));
+ buffer[kk] = '.';
+ if (0 > k + maxDecimalPlaces) {
+ // When maxDecimalPlaces = 2, 1.2345 -> 1.23, 1.102 -> 1.1
+ // Remove extra trailing zeros (at least one) after truncation.
+ for (int i = kk + maxDecimalPlaces; i > kk + 1; i--)
+ if (buffer[i] != '0')
+ return &buffer[i + 1];
+ return &buffer[kk + 2]; // Reserve one zero
+ }
+ else
+ return &buffer[length + 1];
+ }
+ */
+ else if 0 < kk && kk <= 21 {
+ // 1234e-2 -> 12.34
+ ptr::copy(buffer.offset(kk), buffer.offset(kk + 1), (length - kk) as usize);
+ *buffer.offset(kk) = b'.';
+ if 0 > k + MAX_DECIMAL_PLACES {
+ // When MAX_DECIMAL_PLACES = 2, 1.2345 -> 1.23, 1.102 -> 1.1
+ // Remove extra trailing zeros (at least one) after truncation.
+ for i in (kk + 2 .. kk + MAX_DECIMAL_PLACES + 1).rev() {
+ if *buffer.offset(i) != b'0' {
+ return buffer.offset(i + 1);
+ }
+ }
+ buffer.offset(kk + 2) // Reserve one zero
+ } else {
+ buffer.offset(length + 1)
+ }
+ }
+
+ /*
+ else if (-6 < kk && kk <= 0) {
+ // 1234e-6 -> 0.001234
+ const int offset = 2 - kk;
+ std::memmove(&buffer[offset], &buffer[0], static_cast<size_t>(length));
+ buffer[0] = '0';
+ buffer[1] = '.';
+ for (int i = 2; i < offset; i++)
+ buffer[i] = '0';
+ if (length - kk > maxDecimalPlaces) {
+ // When maxDecimalPlaces = 2, 0.123 -> 0.12, 0.102 -> 0.1
+ // Remove extra trailing zeros (at least one) after truncation.
+ for (int i = maxDecimalPlaces + 1; i > 2; i--)
+ if (buffer[i] != '0')
+ return &buffer[i + 1];
+ return &buffer[3]; // Reserve one zero
+ }
+ else
+ return &buffer[length + offset];
+ }
+ */
+ else if -6 < kk && kk <= 0 {
+ // 1234e-6 -> 0.001234
+ let offset = 2 - kk;
+ ptr::copy(buffer, buffer.offset(offset), length as usize);
+ *buffer = b'0';
+ *buffer.offset(1) = b'.';
+ for i in 2..offset {
+ *buffer.offset(i) = b'0';
+ }
+ if length - kk > MAX_DECIMAL_PLACES {
+ // When MAX_DECIMAL_PLACES = 2, 0.123 -> 0.12, 0.102 -> 0.1
+ // Remove extra trailing zeros (at least one) after truncation.
+ for i in (3 .. MAX_DECIMAL_PLACES + 2).rev() {
+ if *buffer.offset(i) != b'0' {
+ return buffer.offset(i + 1);
+ }
+ }
+ buffer.offset(3) // Reserve one zero
+ } else {
+ buffer.offset(length + offset)
+ }
+ }
+
+ /*
+ else if (kk < -maxDecimalPlaces) {
+ // Truncate to zero
+ buffer[0] = '0';
+ buffer[1] = '.';
+ buffer[2] = '0';
+ return &buffer[3];
+ }
+ */
+ else if kk < -MAX_DECIMAL_PLACES {
+ *buffer = b'0';
+ *buffer.offset(1) = b'.';
+ *buffer.offset(2) = b'0';
+ buffer.offset(3)
+ }
+
+ /*
+ else if (length == 1) {
+ // 1e30
+ buffer[1] = 'e';
+ return WriteExponent(kk - 1, &buffer[2]);
+ }
+ */
+ else if length == 1 {
+ // 1e30
+ *buffer.offset(1) = b'e';
+ write_exponent(kk - 1, buffer.offset(2))
+ }
+
+ /*
+ else {
+ // 1234e30 -> 1.234e33
+ std::memmove(&buffer[2], &buffer[1], static_cast<size_t>(length - 1));
+ buffer[1] = '.';
+ buffer[length + 1] = 'e';
+ return WriteExponent(kk - 1, &buffer[0 + length + 2]);
+ }
+ */
+ else {
+ // 1234e30 -> 1.234e33
+ ptr::copy(buffer.offset(1), buffer.offset(2), (length - 1) as usize);
+ *buffer.offset(1) = b'.';
+ *buffer.offset(length + 1) = b'e';
+ write_exponent(kk - 1, buffer.offset(length + 2))
+ }
+}
+
+/*
+inline char* dtoa(double value, char* buffer, int maxDecimalPlaces = 324) {
+ RAPIDJSON_ASSERT(maxDecimalPlaces >= 1);
+ Double d(value);
+ if (d.IsZero()) {
+ if (d.Sign())
+ *buffer++ = '-'; // -0.0, Issue #289
+ buffer[0] = '0';
+ buffer[1] = '.';
+ buffer[2] = '0';
+ return &buffer[3];
+ }
+ else {
+ if (value < 0) {
+ *buffer++ = '-';
+ value = -value;
+ }
+ int length, K;
+ Grisu2(value, buffer, &length, &K);
+ return Prettify(buffer, length, K, maxDecimalPlaces);
+ }
+}
+*/
+
+#[allow(deprecated)]
+#[inline]
+unsafe fn dtoa<W: io::Write>(mut wr: W, mut value: $fty) -> io::Result<usize> {
+ if value == 0.0 {
+ if value.is_sign_negative() {
+ match wr.write_all(b"-0.0") {
+ Ok(()) => Ok(4),
+ Err(e) => Err(e),
+ }
+ } else {
+ match wr.write_all(b"0.0") {
+ Ok(()) => Ok(3),
+ Err(e) => Err(e),
+ }
+ }
+ } else {
+ let negative = value < 0.0;
+ if negative {
+ if let Err(e) = wr.write_all(b"-") {
+ return Err(e);
+ }
+ value = -value;
+ }
+ let mut buffer: [u8; 24] = mem::uninitialized();
+ let buf_ptr = buffer.as_mut_ptr();
+ let (length, k) = grisu2(value, buf_ptr);
+ let end = prettify(buf_ptr, length, k);
+ let len = end as usize - buf_ptr as usize;
+ if let Err(e) = wr.write_all(slice::from_raw_parts(buf_ptr, len)) {
+ return Err(e);
+ }
+ if negative {
+ Ok(len + 1)
+ } else {
+ Ok(len)
+ }
+ }
+}
+
+}}
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