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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server340 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

623 bytes · SHA-256 1f48aabf0fa62ce1… · View upstream ↗

1// Copyright (c) 2021-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#ifndef BITCOIN_UTIL_SERFLOAT_H
6#define BITCOIN_UTIL_SERFLOAT_H
7
8#include <cstdint>
9
10/* Encode a double using the IEEE 754 binary64 format. All NaNs are encoded as x86/ARM's
11 * positive quiet NaN with payload 0. */
12uint64_t EncodeDouble(double f) noexcept;
13/* Reverse operation of DecodeDouble. DecodeDouble(EncodeDouble(f))==f unless isnan(f). */
14double DecodeDouble(uint64_t v) noexcept;
15
16#endif // BITCOIN_UTIL_SERFLOAT_H
17

FILE GUIDE · KEY SECTIONS

A portable representation for serialized doubles

EncodeDouble and DecodeDouble translate between floating-point values and an integer carrying IEEE 754 binary64 bits.

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Normalize NaNs rather than preserve every payload

The contract specifies one positive quiet-NaN encoding with a zero payload. Ordinary values round-trip through encode and decode, but NaN equality is not a meaningful round-trip test. These helpers encode representation; they do not make floating-point arithmetic suitable for exact Bitcoin amounts.

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Bitcoin Core source © its contributors, distributed under the MIT license. Original notices and bundled third-party licenses are retained in the source tree.