Classes
struct	hash_state
	The intermediate state used during hashing. Currently, the algorithm for computing hash codes is based on CityHash and keeps 56 bytes of arbitrary state. More...
struct	is_hashable_data
	Trait to indicate whether a type's bits can be hashed directly. More...
struct	is_hashable_data< std::pair< T, U > >
struct	hash_combine_recursive_helper
	Helper class to manage the recursive combining of hash_combine arguments. More...
Functions
uint64_t	fetch64 (const char *p)
uint32_t	fetch32 (const char *p)
uint64_t	rotate (uint64_t val, size_t shift)
	Bitwise right rotate. Normally this will compile to a single instruction, especially if the shift is a manifest constant.
uint64_t	shift_mix (uint64_t val)
uint64_t	hash_16_bytes (uint64_t low, uint64_t high)
uint64_t	hash_1to3_bytes (const char *s, size_t len, uint64_t seed)
uint64_t	hash_4to8_bytes (const char *s, size_t len, uint64_t seed)
uint64_t	hash_9to16_bytes (const char *s, size_t len, uint64_t seed)
uint64_t	hash_17to32_bytes (const char *s, size_t len, uint64_t seed)
uint64_t	hash_33to64_bytes (const char *s, size_t len, uint64_t seed)
uint64_t	hash_short (const char *s, size_t length, uint64_t seed)
size_t	get_execution_seed ()
template<typename T >
std::enable_if < is_hashable_data< T >::value, T >::type	get_hashable_data (const T &value)
	Helper to get the hashable data representation for a type. This variant is enabled when the type itself can be used.
template<typename T >
bool	store_and_advance (char &buffer_ptr, char buffer_end, const T &value, size_t offset=0)
	Helper to store data from a value into a buffer and advance the pointer into that buffer.
template<typename InputIteratorT >
hash_code	hash_combine_range_impl (InputIteratorT first, InputIteratorT last)
	Implement the combining of integral values into a hash_code.
template<typename ValueT >
std::enable_if < is_hashable_data< ValueT > ::value, hash_code >::type	hash_combine_range_impl (ValueT first, ValueT last)
	Implement the combining of integral values into a hash_code.
hash_code	hash_integer_value (uint64_t value)
	Helper to hash the value of a single integer.
Variables
static const uint64_t	k0 = 0xc3a5c85c97cb3127ULL
	Some primes between 2^63 and 2^64 for various uses.
static const uint64_t	k1 = 0xb492b66fbe98f273ULL
static const uint64_t	k2 = 0x9ae16a3b2f90404fULL
static const uint64_t	k3 = 0xc949d7c7509e6557ULL
size_t	fixed_seed_override = 0
	A global, fixed seed-override variable.

Function Documentation

uint32_t llvm::hashing::detail::fetch32 ( const char * p ) [inline]

Definition at line 159 of file Hashing.h.

References llvm::sys::IsBigEndianHost, llvm::LibFunc::memcpy, and llvm::sys::swapByteOrder().

Referenced by hash_4to8_bytes(), and hash_integer_value().

uint64_t llvm::hashing::detail::fetch64 ( const char * p ) [inline]

Definition at line 151 of file Hashing.h.

References llvm::sys::IsBigEndianHost, llvm::LibFunc::memcpy, and llvm::sys::swapByteOrder().

Referenced by hash_17to32_bytes(), hash_33to64_bytes(), hash_9to16_bytes(), llvm::hashing::detail::hash_state::mix(), and llvm::hashing::detail::hash_state::mix_32_bytes().

size_t llvm::hashing::detail::get_execution_seed ( ) [inline]

Definition at line 327 of file Hashing.h.

References fixed_seed_override.

Referenced by hash_combine_range_impl(), and hash_integer_value().

template<typename T >

std::enable_if<!is_hashable_data< T >::value, size_t >::type llvm::hashing::detail::get_hashable_data ( const T & value )

Helper to get the hashable data representation for a type. This variant is enabled when the type itself can be used.

Helper to get the hashable data representation for a type. This variant is enabled when we must first call hash_value and use the result as our data.

Definition at line 372 of file Hashing.h.

Referenced by llvm::hashing::detail::hash_combine_recursive_helper::combine(), and hash_combine_range_impl().

uint64_t llvm::hashing::detail::hash_16_bytes	(	uint64_t	low,
		uint64_t	high
	)		`[inline]`

Definition at line 185 of file Hashing.h.

Referenced by llvm::hashing::detail::hash_state::create(), llvm::hashing::detail::hash_state::finalize(), hash_17to32_bytes(), hash_4to8_bytes(), hash_9to16_bytes(), and hash_integer_value().

uint64_t llvm::hashing::detail::hash_17to32_bytes	(	const char *	s,
		size_t	len,
		uint64_t	seed
	)		`[inline]`

Definition at line 216 of file Hashing.h.

References fetch64(), hash_16_bytes(), k0, k1, k2, k3, and rotate().

Referenced by hash_short().

uint64_t llvm::hashing::detail::hash_1to3_bytes	(	const char *	s,
		size_t	len,
		uint64_t	seed
	)		`[inline]`

Definition at line 196 of file Hashing.h.

References k2, k3, and shift_mix().

Referenced by hash_short().

uint64_t llvm::hashing::detail::hash_33to64_bytes	(	const char *	s,
		size_t	len,
		uint64_t	seed
	)		`[inline]`

Definition at line 225 of file Hashing.h.

References fetch64(), k0, k2, rotate(), and shift_mix().

Referenced by hash_short().

uint64_t llvm::hashing::detail::hash_4to8_bytes	(	const char *	s,
		size_t	len,
		uint64_t	seed
	)		`[inline]`

Definition at line 205 of file Hashing.h.

References fetch32(), and hash_16_bytes().

Referenced by hash_short().

uint64_t llvm::hashing::detail::hash_9to16_bytes	(	const char *	s,
		size_t	len,
		uint64_t	seed
	)		`[inline]`

Definition at line 210 of file Hashing.h.

References fetch64(), hash_16_bytes(), and rotate().

Referenced by hash_short().

template<typename InputIteratorT >

hash_code llvm::hashing::detail::hash_combine_range_impl	(	InputIteratorT	first,
		InputIteratorT	last
	)

Implement the combining of integral values into a hash_code.

This overload is selected when the value type of the iterator is integral. Rather than computing a hash_code for each object and then combining them, this (as an optimization) directly combines the integers.

Definition at line 410 of file Hashing.h.

References llvm::hashing::detail::hash_state::create(), llvm::sys::path::end(), llvm::hashing::detail::hash_state::finalize(), get_execution_seed(), get_hashable_data(), hash_short(), llvm::hashing::detail::hash_state::mix(), rotate(), and store_and_advance().

Referenced by llvm::hash_combine_range().

template<typename ValueT >

std::enable_if<is_hashable_data<ValueT>::value, hash_code>::type llvm::hashing::detail::hash_combine_range_impl	(	ValueT *	first,
		ValueT *	last
	)

Implement the combining of integral values into a hash_code.

This overload is selected when the value type of the iterator is integral and when the input iterator is actually a pointer. Rather than computing a hash_code for each object and then combining them, this (as an optimization) directly combines the integers. Also, because the integers are stored in contiguous memory, this routine avoids copying each value and directly reads from the underlying memory.

Definition at line 454 of file Hashing.h.

References llvm::hashing::detail::hash_state::create(), get_execution_seed(), hash_short(), and llvm::hashing::detail::hash_state::mix().

hash_code llvm::hashing::detail::hash_integer_value ( uint64_t value ) [inline]

Helper to hash the value of a single integer.

Overloads for smaller integer types are not provided to ensure consistent behavior in the presence of integral promotions. Essentially, "hash_value('4')" and "hash_value('0' + 4)" should be the same.

Definition at line 722 of file Hashing.h.

References fetch32(), get_execution_seed(), and hash_16_bytes().

Referenced by llvm::hash_value().

uint64_t llvm::hashing::detail::hash_short	(	const char *	s,
		size_t	length,
		uint64_t	seed
	)		`[inline]`

Definition at line 248 of file Hashing.h.

References hash_17to32_bytes(), hash_1to3_bytes(), hash_33to64_bytes(), hash_4to8_bytes(), hash_9to16_bytes(), and k2.

Referenced by llvm::hashing::detail::hash_combine_recursive_helper::combine(), and hash_combine_range_impl().

uint64_t llvm::hashing::detail::rotate	(	uint64_t	val,
		size_t	shift
	)		`[inline]`

Bitwise right rotate. Normally this will compile to a single instruction, especially if the shift is a manifest constant.

Definition at line 176 of file Hashing.h.

Referenced by llvm::hashing::detail::hash_combine_recursive_helper::combine(), llvm::hashing::detail::hash_state::create(), hash_17to32_bytes(), hash_33to64_bytes(), hash_9to16_bytes(), hash_combine_range_impl(), llvm::hashing::detail::hash_state::mix(), and llvm::hashing::detail::hash_state::mix_32_bytes().

uint64_t llvm::hashing::detail::shift_mix ( uint64_t val ) [inline]

Definition at line 181 of file Hashing.h.

Referenced by llvm::hashing::detail::hash_state::create(), llvm::hashing::detail::hash_state::finalize(), hash_1to3_bytes(), and hash_33to64_bytes().

template<typename T >

bool llvm::hashing::detail::store_and_advance	(	char *&	buffer_ptr,
		char *	buffer_end,
		const T &	value,
		size_t	offset = `0`
	)

Helper to store data from a value into a buffer and advance the pointer into that buffer.

This routine first checks whether there is enough space in the provided buffer, and if not immediately returns false. If there is space, it copies the underlying bytes of value into the buffer, advances the buffer_ptr past the copied bytes, and returns true.

Definition at line 393 of file Hashing.h.

References llvm::LibFunc::memcpy.

Referenced by llvm::hashing::detail::hash_combine_recursive_helper::combine_data(), and hash_combine_range_impl().