WPILibC++ 2023.4.3
wpi::hashing::detail::hash_state Struct Reference

The intermediate state used during hashing. More...

#include </home/runner/work/allwpilib/allwpilib/wpiutil/src/main/native/thirdparty/llvm/include/wpi/Hashing.h>

Public Member Functions

void mix (const char *s)
 Mix in a 64-byte buffer of data. More...
 
uint64_t finalize (size_t length)
 Compute the final 64-bit hash code value based on the current state and the length of bytes hashed. More...
 

Static Public Member Functions

static hash_state create (const char *s, uint64_t seed)
 Create a new hash_state structure and initialize it based on the seed and the first 64-byte chunk. More...
 
static void mix_32_bytes (const char *s, uint64_t &a, uint64_t &b)
 Mix 32-bytes from the input sequence into the 16-bytes of 'a' and 'b', including whatever is already in 'a' and 'b'. More...
 

Public Attributes

uint64_t h0 = 0
 
uint64_t h1 = 0
 
uint64_t h2 = 0
 
uint64_t h3 = 0
 
uint64_t h4 = 0
 
uint64_t h5 = 0
 
uint64_t h6 = 0
 

Detailed Description

The intermediate state used during hashing.

Currently, the algorithm for computing hash codes is based on CityHash and keeps 56 bytes of arbitrary state.

Member Function Documentation

◆ create()

static hash_state wpi::hashing::detail::hash_state::create ( const char *  s,
uint64_t  seed 
)
inlinestatic

Create a new hash_state structure and initialize it based on the seed and the first 64-byte chunk.

This effectively performs the initial mix.

◆ finalize()

uint64_t wpi::hashing::detail::hash_state::finalize ( size_t  length)
inline

Compute the final 64-bit hash code value based on the current state and the length of bytes hashed.

◆ mix()

void wpi::hashing::detail::hash_state::mix ( const char *  s)
inline

Mix in a 64-byte buffer of data.

We mix all 64 bytes even when the chunk length is smaller, but we record the actual length.

◆ mix_32_bytes()

static void wpi::hashing::detail::hash_state::mix_32_bytes ( const char *  s,
uint64_t &  a,
uint64_t &  b 
)
inlinestatic

Mix 32-bytes from the input sequence into the 16-bytes of 'a' and 'b', including whatever is already in 'a' and 'b'.

Member Data Documentation

◆ h0

uint64_t wpi::hashing::detail::hash_state::h0 = 0

◆ h1

uint64_t wpi::hashing::detail::hash_state::h1 = 0

◆ h2

uint64_t wpi::hashing::detail::hash_state::h2 = 0

◆ h3

uint64_t wpi::hashing::detail::hash_state::h3 = 0

◆ h4

uint64_t wpi::hashing::detail::hash_state::h4 = 0

◆ h5

uint64_t wpi::hashing::detail::hash_state::h5 = 0

◆ h6

uint64_t wpi::hashing::detail::hash_state::h6 = 0

The documentation for this struct was generated from the following file: