cgen – C-Generation Reference Documentation¶

Data and Functions¶

class cgen.FunctionBody(fdecl, body)¶

Bases: cgen.Generable

Initialize a function definition. fdecl is expected to be a FunctionDeclaration instance, while body is a Block.

class cgen.Initializer(vdecl, data)¶

Bases: cgen.Generable

Preprocessor Code¶

class cgen.Define(symbol, value)¶

Bases: cgen.Generable

class cgen.Comment(text)¶

Bases: cgen.Generable

class cgen.Include(filename, system=True)¶

Bases: cgen.Generable

class cgen.Pragma(value)¶

Bases: cgen.Generable

Declarators¶

class cgen.Declarator¶

Bases: cgen.Generable

get_decl_pair()¶

Return a tuple (type_lines, rhs).

type_lines is a non-empty list of lines (most often just a single one) describing the type of this declarator. rhs is the right- hand side that actually contains the function/array/constness notation making up the bulk of the declarator syntax.

inline(with_semicolon=True)¶

Return the declarator as a single line.

class cgen.Value(typename, name)¶

Bases: cgen.Declarator

A simple declarator: typename and name are given as strings.

class cgen.POD(dtype, name)¶

Bases: cgen.Declarator

A simple declarator: The type is given as a numpy.dtype and the name is given as a string.

class cgen.Struct(tpname, fields, declname=None, pad_bytes=0)¶

Bases: cgen.Declarator

A structure declarator.

Initialize the structure declarator. tpname is the name of the structure, while declname is the name used for the declarator. pad_bytes is the number of padding bytes added at the end of the structure. fields is a list of Declarator instances.

class cgen.GenerableStruct(tpname, fields, declname=None, align_bytes=None, aligned_prime_to=[])¶

Bases: cgen.Struct

Initialize a structure declarator. tpname is the name of the structure, while declname is the name used for the declarator. pad_bytes is the number of padding bytes added at the end of the structure. fields is a list of Declarator instances.

align_bytes is an integer that causes the structure to be padded to an integer multiple of itself. aligned_prime_to is a list of integers. If the resulting structure’s size is s, then s//align_bytes will be made prime to all numbers in aligned_prime_to. (Sounds obscure? It’s needed for avoiding bank conflicts in CUDA programming.)

__init__(tpname, fields, declname=None, align_bytes=None, aligned_prime_to=[])¶

Initialize a structure declarator. tpname is the name of the structure, while declname is the name used for the declarator. pad_bytes is the number of padding bytes added at the end of the structure. fields is a list of Declarator instances.

align_bytes is an integer that causes the structure to be padded to an integer multiple of itself. aligned_prime_to is a list of integers. If the resulting structure’s size is s, then s//align_bytes will be made prime to all numbers in aligned_prime_to. (Sounds obscure? It’s needed for avoiding bank conflicts in CUDA programming.)

__len__()¶

Return the number of bytes occupied by this struct.

make(**kwargs)¶

Build a binary, packed representation of self in a str instance with members set to the values specified in kwargs.

make_with_defaults(**kwargs)¶

Build a binary, packed representation of self in a str instance with members set to the values specified in kwargs.

Unlike make(), not all members have to occur in kwargs.

struct_format()¶

Return the format of the struct as digested by the struct module.

Nested Declarators¶

class cgen.NestedDeclarator(subdecl)¶

Bases: cgen.Declarator

class cgen.ArrayOf(subdecl, count=None)¶

Bases: cgen.NestedDeclarator

class cgen.Const(subdecl)¶

Bases: cgen.NestedDeclarator

class cgen.FunctionDeclaration(subdecl, arg_decls)¶

Bases: cgen.NestedDeclarator

class cgen.MaybeUnused(subdecl)¶

Bases: cgen.NestedDeclarator

class cgen.Pointer(subdecl)¶

Bases: cgen.NestedDeclarator

class cgen.Reference(subdecl)¶

Bases: cgen.Pointer

class cgen.Template(template_spec, subdecl)¶

Bases: cgen.NestedDeclarator

Declaration Specifiers¶

class cgen.DeclSpecifier(subdecl, spec, sep=' ')¶

Bases: cgen.NestedDeclarator

class cgen.Static(subdecl)¶

Bases: cgen.DeclSpecifier

class cgen.Typedef(subdecl)¶

Bases: cgen.DeclSpecifier

Statements¶

class cgen.Statement(text)¶

Bases: cgen.Generable

class cgen.Assign(lvalue, rvalue)¶

Bases: cgen.Generable

class cgen.If(condition, then_, else_=None)¶

Bases: cgen.Generable

cgen.make_multiple_ifs(conditions_and_blocks, base=None)¶

class cgen.DoWhile(condition, body)¶

Bases: cgen.Loop

class cgen.For(start, condition, update, body)¶

Bases: cgen.Loop

class cgen.While(condition, body)¶

Bases: cgen.Loop

cgen.cuda – Extensions to generate CUDA-compatible C Sources¶

This module adds a few Nvidia CUDA features to cgen’s repertoire. This makes cgen a perfect complement to PyCuda: cgen generates the code, PyCuda compiles it, uploads it to the GPU and executes it.

The PyCuda manual has a tutorial on using the two together.

class cgen.cuda.CudaGlobal(subdecl)¶

Bases: cgen.DeclSpecifier

class cgen.cuda.CudaDevice(subdecl)¶

Bases: cgen.DeclSpecifier

class cgen.cuda.CudaShared(subdecl)¶

Bases: cgen.DeclSpecifier

class cgen.cuda.CudaConstant(subdecl)¶

Bases: cgen.DeclSpecifier

cgen.opencl – Extensions to generate OpenCL-compatible C Sources¶

cgen.opencl.dtype_to_cltype(dtype)¶