Type

struct Type

Types in the halide type system.

They can be ints, unsigned ints, or floats of various bit-widths (the ‘bits’ field). They can also be vectors of the same (by setting the ‘lanes’ field to something larger than one). Front-end code shouldn’t use vector types. Instead vectorize a function.

Public Functions

inline int bytes() const

The number of bytes required to store a single scalar value of this type.

Ignores vector lanes.

inline Type(halide_type_code_t code, int bits, int lanes, const halide_handle_cplusplus_type *handle_type = nullptr)

Construct a runtime representation of a Halide type from: code: The fundamental type from an enum.

bits: The bit size of one element. lanes: The number of vector elements in the type.

Type(const Type &that) = default

Trivial copy constructor.

Type &operator=(const Type &that) = default

Trivial copy assignment operator.

inline Type(halide_type_t that, const halide_handle_cplusplus_type *handle_type = nullptr)

Construct a (scalar) language Type from an ABI element type.

inline halide_type_t to_abi() const

Erase this language Type to the ABI/runtime halide_type_t for use in runtime calls, buffer/argument metadata, etc.

This is a checked erasure: the ABI element type has no lanes, so a vector type (lanes >= 2) has no image here and asserts rather than silently dropping its lanes.

inline halide_type_code_t code() const

Return the underlying data type of an element as an enum value.

inline int bits() const

Return the bit size of a single element of this type.

inline int lanes() const

Return the number of vector elements in this type.

inline Type with_code(halide_type_code_t new_code) const

Return Type with same number of bits and lanes, but new_code for a type code.

inline Type with_bits(int new_bits) const

Return Type with same type code and lanes, but new_bits for the number of bits.

inline Type with_lanes(int new_lanes) const

Return Type with same type code and number of bits, but new_lanes for the number of vector lanes.

inline Type widen() const

Return Type with the same type code and number of lanes, but with at least twice as many bits.

inline Type narrow() const

Return Type with the same type code and number of lanes, but with at most half as many bits.

inline const halide_handle_cplusplus_type *handle_type() const

The externally-owned C++ type metadata for a handle type (null for a plain void * handle or a non-handle type).

Backed by a 4-byte intern index rather than stored inline, so this is now an accessor rather than a public field.

inline bool is_bool() const

Is this type boolean (represented as UInt(1))?

inline bool is_vector() const

Is this type a vector type?

(lanes() != 1). TODO(abadams): Decide what to do for lanes() == 0.

inline bool is_scalar() const

Is this type a scalar type?

(lanes() == 1). TODO(abadams): Decide what to do for lanes() == 0.

inline bool is_float() const

Is this type a floating point type (float or double).

inline bool is_bfloat() const

Is this type a floating point type (float or double).

inline bool is_int() const

Is this type a signed integer type?

inline bool is_uint() const

Is this type an unsigned integer type?

inline bool is_int_or_uint() const

Is this type an integer type of any sort?

inline bool is_handle() const

Is this type an opaque handle type (void *).

bool same_handle_type(const Type &other) const

Check that the type name of two handles matches.

inline bool operator==(const Type &other) const

Compare two types for equality.

inline bool operator!=(const Type &other) const

Compare two types for inequality.

inline bool operator==(const halide_type_t &other) const

Compare a language type to an ABI element type.

Equal iff this type is a single element (not a vector) with the same code and bits.

inline bool operator!=(const halide_type_t &other) const

Compare two types for inequality.

inline bool operator<(const Type &other) const

Compare ordering of two types so they can be used in certain containers and algorithms.

inline Type element_of() const

Produce the scalar type (that of a single element) of this vector type.

bool can_represent(Type other) const

Can this type represent all values of another type?

bool can_represent(const Internal::ConstantInterval &in) const

Can this type represent exactly all integer values of some constant integer range?

bool can_represent(double x) const

Can this type represent a particular constant?

bool is_max(uint64_t) const

Check if an integer constant value is the maximum or minimum representable value for this type.

Expr max() const

Return an expression which is the maximum value of this type.

Returns infinity for types which can represent it.

Expr min() const

Return an expression which is the minimum value of this type.

Returns -infinity for types which can represent it.

Public Static Attributes

static halide_type_code_t Int = halide_type_int

Aliases for halide_type_code_t values for legacy compatibility and to match the Halide internal C++ style.

static int kLanesBits = 8 * sizeof(type_lanes)

Exposed so code that needs to reason about the maximum representable lanes count (e.g.

overflow checks when combining vectors) can derive it from Type itself instead of hardcoding a width.