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-rw-r--r--vendor/ryu/src/s2f.rs227
1 files changed, 0 insertions, 227 deletions
diff --git a/vendor/ryu/src/s2f.rs b/vendor/ryu/src/s2f.rs
deleted file mode 100644
index 9593528..0000000
--- a/vendor/ryu/src/s2f.rs
+++ /dev/null
@@ -1,227 +0,0 @@
-use crate::common::*;
-use crate::f2s;
-use crate::f2s_intrinsics::*;
-use crate::parse::Error;
-#[cfg(feature = "no-panic")]
-use no_panic::no_panic;
-
-const FLOAT_EXPONENT_BIAS: usize = 127;
-
-fn floor_log2(value: u32) -> u32 {
- 31_u32.wrapping_sub(value.leading_zeros())
-}
-
-#[cfg_attr(feature = "no-panic", no_panic)]
-pub fn s2f(buffer: &[u8]) -> Result<f32, Error> {
- let len = buffer.len();
- if len == 0 {
- return Err(Error::InputTooShort);
- }
-
- let mut m10digits = 0;
- let mut e10digits = 0;
- let mut dot_index = len;
- let mut e_index = len;
- let mut m10 = 0u32;
- let mut e10 = 0i32;
- let mut signed_m = false;
- let mut signed_e = false;
-
- let mut i = 0;
- if unsafe { *buffer.get_unchecked(0) } == b'-' {
- signed_m = true;
- i += 1;
- }
-
- while let Some(c) = buffer.get(i).copied() {
- if c == b'.' {
- if dot_index != len {
- return Err(Error::MalformedInput);
- }
- dot_index = i;
- i += 1;
- continue;
- }
- if c < b'0' || c > b'9' {
- break;
- }
- if m10digits >= 9 {
- return Err(Error::InputTooLong);
- }
- m10 = 10 * m10 + (c - b'0') as u32;
- if m10 != 0 {
- m10digits += 1;
- }
- i += 1;
- }
-
- if let Some(b'e') | Some(b'E') = buffer.get(i) {
- e_index = i;
- i += 1;
- match buffer.get(i) {
- Some(b'-') => {
- signed_e = true;
- i += 1;
- }
- Some(b'+') => i += 1,
- _ => {}
- }
- while let Some(c) = buffer.get(i).copied() {
- if c < b'0' || c > b'9' {
- return Err(Error::MalformedInput);
- }
- if e10digits > 3 {
- // TODO: Be more lenient. Return +/-Infinity or +/-0 instead.
- return Err(Error::InputTooLong);
- }
- e10 = 10 * e10 + (c - b'0') as i32;
- if e10 != 0 {
- e10digits += 1;
- }
- i += 1;
- }
- }
-
- if i < len {
- return Err(Error::MalformedInput);
- }
- if signed_e {
- e10 = -e10;
- }
- e10 -= if dot_index < e_index {
- (e_index - dot_index - 1) as i32
- } else {
- 0
- };
- if m10 == 0 {
- return Ok(if signed_m { -0.0 } else { 0.0 });
- }
-
- if m10digits + e10 <= -46 || m10 == 0 {
- // Number is less than 1e-46, which should be rounded down to 0; return
- // +/-0.0.
- let ieee = (signed_m as u32) << (f2s::FLOAT_EXPONENT_BITS + f2s::FLOAT_MANTISSA_BITS);
- return Ok(f32::from_bits(ieee));
- }
- if m10digits + e10 >= 40 {
- // Number is larger than 1e+39, which should be rounded to +/-Infinity.
- let ieee = ((signed_m as u32) << (f2s::FLOAT_EXPONENT_BITS + f2s::FLOAT_MANTISSA_BITS))
- | (0xff_u32 << f2s::FLOAT_MANTISSA_BITS);
- return Ok(f32::from_bits(ieee));
- }
-
- // Convert to binary float m2 * 2^e2, while retaining information about
- // whether the conversion was exact (trailing_zeros).
- let e2: i32;
- let m2: u32;
- let mut trailing_zeros: bool;
- if e10 >= 0 {
- // The length of m * 10^e in bits is:
- // log2(m10 * 10^e10) = log2(m10) + e10 log2(10) = log2(m10) + e10 + e10 * log2(5)
- //
- // We want to compute the FLOAT_MANTISSA_BITS + 1 top-most bits (+1 for
- // the implicit leading one in IEEE format). We therefore choose a
- // binary output exponent of
- // log2(m10 * 10^e10) - (FLOAT_MANTISSA_BITS + 1).
- //
- // We use floor(log2(5^e10)) so that we get at least this many bits; better to
- // have an additional bit than to not have enough bits.
- e2 = floor_log2(m10)
- .wrapping_add(e10 as u32)
- .wrapping_add(log2_pow5(e10) as u32)
- .wrapping_sub(f2s::FLOAT_MANTISSA_BITS + 1) as i32;
-
- // We now compute [m10 * 10^e10 / 2^e2] = [m10 * 5^e10 / 2^(e2-e10)].
- // To that end, we use the FLOAT_POW5_SPLIT table.
- let j = e2
- .wrapping_sub(e10)
- .wrapping_sub(ceil_log2_pow5(e10))
- .wrapping_add(f2s::FLOAT_POW5_BITCOUNT);
- debug_assert!(j >= 0);
- m2 = mul_pow5_div_pow2(m10, e10 as u32, j);
-
- // We also compute if the result is exact, i.e.,
- // [m10 * 10^e10 / 2^e2] == m10 * 10^e10 / 2^e2.
- // This can only be the case if 2^e2 divides m10 * 10^e10, which in turn
- // requires that the largest power of 2 that divides m10 + e10 is
- // greater than e2. If e2 is less than e10, then the result must be
- // exact. Otherwise we use the existing multiple_of_power_of_2 function.
- trailing_zeros =
- e2 < e10 || e2 - e10 < 32 && multiple_of_power_of_2_32(m10, (e2 - e10) as u32);
- } else {
- e2 = floor_log2(m10)
- .wrapping_add(e10 as u32)
- .wrapping_sub(ceil_log2_pow5(-e10) as u32)
- .wrapping_sub(f2s::FLOAT_MANTISSA_BITS + 1) as i32;
-
- // We now compute [m10 * 10^e10 / 2^e2] = [m10 / (5^(-e10) 2^(e2-e10))].
- let j = e2
- .wrapping_sub(e10)
- .wrapping_add(ceil_log2_pow5(-e10))
- .wrapping_sub(1)
- .wrapping_add(f2s::FLOAT_POW5_INV_BITCOUNT);
- m2 = mul_pow5_inv_div_pow2(m10, -e10 as u32, j);
-
- // We also compute if the result is exact, i.e.,
- // [m10 / (5^(-e10) 2^(e2-e10))] == m10 / (5^(-e10) 2^(e2-e10))
- //
- // If e2-e10 >= 0, we need to check whether (5^(-e10) 2^(e2-e10))
- // divides m10, which is the case iff pow5(m10) >= -e10 AND pow2(m10) >=
- // e2-e10.
- //
- // If e2-e10 < 0, we have actually computed [m10 * 2^(e10 e2) /
- // 5^(-e10)] above, and we need to check whether 5^(-e10) divides (m10 *
- // 2^(e10-e2)), which is the case iff pow5(m10 * 2^(e10-e2)) = pow5(m10)
- // >= -e10.
- trailing_zeros = (e2 < e10
- || (e2 - e10 < 32 && multiple_of_power_of_2_32(m10, (e2 - e10) as u32)))
- && multiple_of_power_of_5_32(m10, -e10 as u32);
- }
-
- // Compute the final IEEE exponent.
- let mut ieee_e2 = i32::max(0, e2 + FLOAT_EXPONENT_BIAS as i32 + floor_log2(m2) as i32) as u32;
-
- if ieee_e2 > 0xfe {
- // Final IEEE exponent is larger than the maximum representable; return
- // +/-Infinity.
- let ieee = ((signed_m as u32) << (f2s::FLOAT_EXPONENT_BITS + f2s::FLOAT_MANTISSA_BITS))
- | (0xff_u32 << f2s::FLOAT_MANTISSA_BITS);
- return Ok(f32::from_bits(ieee));
- }
-
- // We need to figure out how much we need to shift m2. The tricky part is
- // that we need to take the final IEEE exponent into account, so we need to
- // reverse the bias and also special-case the value 0.
- let shift = if ieee_e2 == 0 { 1 } else { ieee_e2 as i32 }
- .wrapping_sub(e2)
- .wrapping_sub(FLOAT_EXPONENT_BIAS as i32)
- .wrapping_sub(f2s::FLOAT_MANTISSA_BITS as i32);
- debug_assert!(shift >= 0);
-
- // We need to round up if the exact value is more than 0.5 above the value
- // we computed. That's equivalent to checking if the last removed bit was 1
- // and either the value was not just trailing zeros or the result would
- // otherwise be odd.
- //
- // We need to update trailing_zeros given that we have the exact output
- // exponent ieee_e2 now.
- trailing_zeros &= (m2 & ((1_u32 << (shift - 1)) - 1)) == 0;
- let last_removed_bit = (m2 >> (shift - 1)) & 1;
- let round_up = last_removed_bit != 0 && (!trailing_zeros || ((m2 >> shift) & 1) != 0);
-
- let mut ieee_m2 = (m2 >> shift).wrapping_add(round_up as u32);
- debug_assert!(ieee_m2 <= 1_u32 << (f2s::FLOAT_MANTISSA_BITS + 1));
- ieee_m2 &= (1_u32 << f2s::FLOAT_MANTISSA_BITS) - 1;
- if ieee_m2 == 0 && round_up {
- // Rounding up may overflow the mantissa.
- // In this case we move a trailing zero of the mantissa into the
- // exponent.
- // Due to how the IEEE represents +/-Infinity, we don't need to check
- // for overflow here.
- ieee_e2 += 1;
- }
- let ieee = ((((signed_m as u32) << f2s::FLOAT_EXPONENT_BITS) | ieee_e2)
- << f2s::FLOAT_MANTISSA_BITS)
- | ieee_m2;
- Ok(f32::from_bits(ieee))
-}
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