Implementation of the HashBuilder interface. More...

#include "llvm/Support/HashBuilder.h"

Inheritance diagram for llvm::HashBuilderImpl< HasherT, Endianness >:

Public Types
template<typename T >
using	HasAddHashT = decltype(addHash(std::declval< HashBuilderImpl & >(), std::declval< T & >()))

template<typename T >
using	HasByteSwapT = decltype(support::endian::byte_swap(std::declval< T & >(), support::endianness::little))

Public Types inherited from llvm::HashBuilderBase< HasherT >
template<typename HasherT_ = HasherT>
using	HashResultTy = decltype(std::declval< HasherT_ & >().final())

Public Member Functions
	HashBuilderImpl (HasherT &Hasher)

template<typename... ArgTypes>
	HashBuilderImpl (ArgTypes &&...Args)

template<typename T >
std::enable_if_t< hashbuilder_detail::IsHashableData< T >::value, HashBuilderImpl & >	add (T Value)
	Implement hashing for hashable data types, e.g. integral or enum values.

template<typename T >
HashBuilderImpl &	add (ArrayRef< T > Value)
	Support hashing `ArrayRef`.

HashBuilderImpl &	add (StringRef Value)
	Support hashing `StringRef`.

template<typename T >
std::enable_if_t< is_detected< HasAddHashT, T >::value &&!hashbuilder_detail::IsHashableData< T >::value, HashBuilderImpl & >	add (const T &Value)
	Implement hashing for user-defined `struct`s.

template<typename T1 , typename T2 >
HashBuilderImpl &	add (const std::pair< T1, T2 > &Value)

template<typename... Ts>
HashBuilderImpl &	add (const std::tuple< Ts... > &Arg)

template<typename... Ts>
std::enable_if_t<(sizeof...(Ts) > 1), HashBuilderImpl & >	add (const Ts &...Args)
	A convenenience variadic helper.

template<typename ForwardIteratorT >
HashBuilderImpl &	addRange (ForwardIteratorT First, ForwardIteratorT Last)

template<typename RangeT >
HashBuilderImpl &	addRange (const RangeT &Range)

template<typename ForwardIteratorT >
HashBuilderImpl &	addRangeElements (ForwardIteratorT First, ForwardIteratorT Last)

template<typename RangeT >
HashBuilderImpl &	addRangeElements (const RangeT &Range)

template<typename T >
std::enable_if_t< is_detected< HasByteSwapT, T >::value, HashBuilderImpl & >	adjustForEndiannessAndAdd (const T &Value)
	Adjust `Value` for the target endianness and add it to the hash.

Public Member Functions inherited from llvm::HashBuilderBase< HasherT >
HasherT &	getHasher ()

void	update (ArrayRef< uint8_t > Data)
	Forward to `HasherT::update(ArrayRef<uint8_t>)`.

void	update (StringRef Data)
	Forward to `HasherT::update(ArrayRef<uint8_t>)`.

template<typename HasherT_ = HasherT>
HashResultTy< HasherT_ >	final ()
	Forward to `HasherT::final()` if available.

template<typename HasherT_ = HasherT>
HashResultTy< HasherT_ >	result ()
	Forward to `HasherT::result()` if available.

Additional Inherited Members
Protected Member Functions inherited from llvm::HashBuilderBase< HasherT >
	HashBuilderBase (HasherT &Hasher)

template<typename... ArgTypes>
	HashBuilderBase (ArgTypes &&...Args)

Detailed Description

template<typename HasherT, support::endianness Endianness>
class llvm::HashBuilderImpl< HasherT, Endianness >

Implementation of the HashBuilder interface.

support::endianness::native is not supported. HashBuilder is expected to canonicalize support::endianness::native to one of support::endianness::big or support::endianness::little.

Definition at line 94 of file HashBuilder.h.

Member Typedef Documentation

◆ HasAddHashT

template<typename HasherT , support::endianness Endianness>

template<typename T >

using llvm::HashBuilderImpl< HasherT, Endianness >::HasAddHashT = decltype(addHash(std::declval<HashBuilderImpl &>(), std::declval<T &>()))

Definition at line 168 of file HashBuilder.h.

◆ HasByteSwapT

template<typename HasherT , support::endianness Endianness>

template<typename T >

using llvm::HashBuilderImpl< HasherT, Endianness >::HasByteSwapT = decltype(support::endian::byte_swap( std::declval<T &>(), support::endianness::little))

Definition at line 312 of file HashBuilder.h.

Constructor & Destructor Documentation

◆ HashBuilderImpl() [1/2]

template<typename HasherT , support::endianness Endianness>

llvm::HashBuilderImpl< HasherT, Endianness >::HashBuilderImpl ( HasherT & Hasher )

inlineexplicit

Definition at line 99 of file HashBuilder.h.

◆ HashBuilderImpl() [2/2]

template<typename HasherT , support::endianness Endianness>

template<typename... ArgTypes>

llvm::HashBuilderImpl< HasherT, Endianness >::HashBuilderImpl ( ArgTypes &&... Args )

inlineexplicit

Definition at line 102 of file HashBuilder.h.

Member Function Documentation

◆ add() [1/7]

template<typename HasherT , support::endianness Endianness>

template<typename T >

HashBuilderImpl & llvm::HashBuilderImpl< HasherT, Endianness >::add ( ArrayRef< T > Value )

inline

Support hashing ArrayRef.

Value.size() is taken into account to ensure cases like

builder.add({1});

builder.add({2, 3});

builder

assume builder

Definition: AssumeBundleBuilder.cpp:622

and

builder.add({1, 2});

builder.add({3});

do not collide.

Definition at line 126 of file HashBuilder.h.

References llvm::HashBuilderImpl< HasherT, Endianness >::add(), llvm::support::endian::system_endianness(), and llvm::HashBuilderBase< HasherT >::update().

◆ add() [2/7]

template<typename HasherT , support::endianness Endianness>

template<typename T1 , typename T2 >

HashBuilderImpl & llvm::HashBuilderImpl< HasherT, Endianness >::add ( const std::pair< T1, T2 > & Value )

inline

Definition at line 263 of file HashBuilder.h.

References llvm::HashBuilderImpl< HasherT, Endianness >::add().

◆ add() [3/7]

template<typename HasherT , support::endianness Endianness>

template<typename... Ts>

HashBuilderImpl & llvm::HashBuilderImpl< HasherT, Endianness >::add ( const std::tuple< Ts... > & Arg )

inline

Definition at line 267 of file HashBuilder.h.

References llvm::HashBuilderImpl< HasherT, Endianness >::add().

◆ add() [4/7]

template<typename HasherT , support::endianness Endianness>

template<typename T >

std::enable_if_t< is_detected< HasAddHashT, T >::value && !hashbuilder_detail::IsHashableData< T >::value, HashBuilderImpl & > llvm::HashBuilderImpl< HasherT, Endianness >::add ( const T & Value )

inline

Implement hashing for user-defined structs.

Any user-define struct can participate in hashing via HashBuilder by providing a addHash templated function.

template <typename HasherT, support::endianness Endianness>
void addHash(HashBuilder<HasherT, Endianness> &HBuilder,
             const UserDefinedStruct &Value);

For example:

struct SimpleStruct {
  char c;
  int i;
};
 
template <typename HasherT, support::endianness Endianness>
void addHash(HashBuilderImpl<HasherT, Endianness> &HBuilder,
             const SimpleStruct &Value) {
  HBuilder.add(Value.c);
  HBuilder.add(Value.i);
}

To avoid endianness issues, specializations of addHash should generally rely on exising add, addRange, and addRangeElements functions. If directly using update, an implementation must correctly handle endianness.

struct __attribute__ ((packed)) StructWithFastHash {
  int I;
  char C;
 
  // If possible, we want to hash both `I` and `C` in a single
  // `update` call for performance concerns.
  template <typename HasherT, support::endianness Endianness>
  friend void addHash(HashBuilderImpl<HasherT, Endianness> &HBuilder,
                      const StructWithFastHash &Value) {
    if (Endianness == support::endian::system_endianness()) {
      HBuilder.update(ArrayRef(
          reinterpret_cast<const uint8_t *>(&Value), sizeof(Value)));
    } else {
      // Rely on existing `add` methods to handle endianness.
      HBuilder.add(Value.I);
      HBuilder.add(Value.C);
    }
  }
};

To avoid collisions, specialization of addHash for variable-size types must take the size into account.

For example:

struct CustomContainer {
private:
  size_t Size;
  int Elements[100];
 
public:
  CustomContainer(size_t Size) : Size(Size) {
    for (size_t I = 0; I != Size; ++I)
      Elements[I] = I;
  }
  template <typename HasherT, support::endianness Endianness>
  friend void addHash(HashBuilderImpl<HasherT, Endianness> &HBuilder,
                      const CustomContainer &Value) {
    if (Endianness == support::endian::system_endianness()) {
      HBuilder.update(ArrayRef(
          reinterpret_cast<const uint8_t *>(&Value.Size),
          sizeof(Value.Size) + Value.Size * sizeof(Value.Elements[0])));
    } else {
      // `addRange` will take care of encoding the size.
      HBuilder.addRange(&Value.Elements[0], &Value.Elements[0] +
      Value.Size);
    }
  }
};

Definition at line 257 of file HashBuilder.h.

◆ add() [5/7]

template<typename HasherT , support::endianness Endianness>

template<typename... Ts>

std::enable_if_t<(sizeof...(Ts) > 1), HashBuilderImpl & > llvm::HashBuilderImpl< HasherT, Endianness >::add ( const Ts &... Args )

inline

A convenenience variadic helper.

It simply iterates over its arguments, in order.

add(Arg1, Arg2);

is equivalent to

add(Arg1)

add(Arg2)

Definition at line 284 of file HashBuilder.h.

References llvm::HashBuilderImpl< HasherT, Endianness >::add().

◆ add() [6/7]

template<typename HasherT , support::endianness Endianness>

HashBuilderImpl & llvm::HashBuilderImpl< HasherT, Endianness >::add ( StringRef Value )

inline

Support hashing StringRef.

Value.size() is taken into account to ensure cases like

builder.add("a");

builder.add("bc");

and

builder.add("ab");

builder.add("c");

do not collide.

Definition at line 156 of file HashBuilder.h.

References llvm::HashBuilderImpl< HasherT, Endianness >::add(), and llvm::HashBuilderBase< HasherT >::update().

◆ add() [7/7]

template<typename HasherT , support::endianness Endianness>

template<typename T >

std::enable_if_t< hashbuilder_detail::IsHashableData< T >::value, HashBuilderImpl & > llvm::HashBuilderImpl< HasherT, Endianness >::add ( T Value )

inline

Implement hashing for hashable data types, e.g. integral or enum values.

Definition at line 109 of file HashBuilder.h.

References llvm::HashBuilderImpl< HasherT, Endianness >::adjustForEndiannessAndAdd().

Referenced by llvm::HashBuilderImpl< HasherT, Endianness >::add(), llvm::HashBuilderImpl< HasherT, Endianness >::addRange(), computeStackId(), and llvm::hash_value().

◆ addRange() [1/2]

template<typename HasherT , support::endianness Endianness>

template<typename RangeT >

HashBuilderImpl & llvm::HashBuilderImpl< HasherT, Endianness >::addRange ( const RangeT & Range )

inline

Definition at line 294 of file HashBuilder.h.

References llvm::HashBuilderImpl< HasherT, Endianness >::addRange(), llvm::adl_begin(), and llvm::adl_end().

◆ addRange() [2/2]

template<typename HasherT , support::endianness Endianness>

template<typename ForwardIteratorT >

HashBuilderImpl & llvm::HashBuilderImpl< HasherT, Endianness >::addRange	(	ForwardIteratorT	First,
		ForwardIteratorT	Last
	)

inline

Definition at line 289 of file HashBuilder.h.

References llvm::HashBuilderImpl< HasherT, Endianness >::add(), llvm::HashBuilderImpl< HasherT, Endianness >::addRangeElements(), llvm::First, and llvm::Last.

Referenced by llvm::HashBuilderImpl< HasherT, Endianness >::addRange().

◆ addRangeElements() [1/2]

template<typename HasherT , support::endianness Endianness>

template<typename RangeT >

HashBuilderImpl & llvm::HashBuilderImpl< HasherT, Endianness >::addRangeElements ( const RangeT & Range )

inline

Definition at line 307 of file HashBuilder.h.

References llvm::HashBuilderImpl< HasherT, Endianness >::addRangeElements(), llvm::adl_begin(), and llvm::adl_end().

◆ addRangeElements() [2/2]

template<typename HasherT , support::endianness Endianness>

template<typename ForwardIteratorT >

HashBuilderImpl & llvm::HashBuilderImpl< HasherT, Endianness >::addRangeElements	(	ForwardIteratorT	First,
		ForwardIteratorT	Last
	)

inline

Definition at line 299 of file HashBuilder.h.

References llvm::First, and llvm::Last.

Referenced by llvm::HashBuilderImpl< HasherT, Endianness >::addRange(), and llvm::HashBuilderImpl< HasherT, Endianness >::addRangeElements().

◆ adjustForEndiannessAndAdd()

template<typename HasherT , support::endianness Endianness>

template<typename T >

std::enable_if_t< is_detected< HasByteSwapT, T >::value, HashBuilderImpl & > llvm::HashBuilderImpl< HasherT, Endianness >::adjustForEndiannessAndAdd ( const T & Value )

inline

Adjust Value for the target endianness and add it to the hash.

Definition at line 317 of file HashBuilder.h.

References llvm::support::endian::byte_swap(), and llvm::HashBuilderBase< HasherT >::update().

Referenced by llvm::HashBuilderImpl< HasherT, Endianness >::add().

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

include/llvm/Support/HashBuilder.h

Public Types

Public Member Functions

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ HasAddHashT

◆ HasByteSwapT

Constructor & Destructor Documentation

◆ HashBuilderImpl() [1/2]

◆ HashBuilderImpl() [2/2]

Member Function Documentation

◆ add() [1/7]

◆ add() [2/7]

◆ add() [3/7]

◆ add() [4/7]

◆ add() [5/7]

◆ add() [6/7]

◆ add() [7/7]

◆ addRange() [1/2]

◆ addRange() [2/2]

◆ addRangeElements() [1/2]

◆ addRangeElements() [2/2]

◆ adjustForEndiannessAndAdd()