Halide
DeviceArgument.h
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1 #ifndef HALIDE_DEVICE_ARGUMENT_H
2 #define HALIDE_DEVICE_ARGUMENT_H
3 
4 /** \file
5  * Defines helpers for passing arguments to separate devices, such as GPUs.
6  */
7 #include <string>
8 
9 #include "Closure.h"
10 #include "Expr.h"
11 #include "ModulusRemainder.h"
12 
13 namespace Halide {
14 namespace Internal {
15 
16 /** A DeviceArgument looks similar to an Halide::Argument, but has behavioral
17  * differences that make it specific to the GPU pipeline; the fact that
18  * neither is-a nor has-a Halide::Argument is deliberate. In particular, note
19  * that a Halide::Argument that is a buffer can be read or write, but not both,
20  * while a DeviceArgument that is a buffer can be read *and* write for some GPU
21  * backends. */
23  /** The name of the argument */
24  std::string name;
25 
26  /** An argument is either a primitive type (for parameters), or a
27  * buffer pointer.
28  *
29  * If is_buffer == false, then type fully encodes the expected type
30  * of the scalar argument.
31  *
32  * If is_buffer == true, then type.bytes() should be used to determine
33  * elem_size of the buffer; additionally, type.code *should* reflect
34  * the expected interpretation of the buffer data (e.g. float vs int),
35  * but there is no runtime enforcement of this at present.
36  */
37  bool is_buffer = false;
38 
39  /** If is_buffer == true and memory_type == GPUTexture, this argument should be
40  * passed and accessed through texture sampler operations instead of
41  * directly as a memory array
42  */
44 
45  /** If is_buffer is true, this is the dimensionality of the buffer.
46  * If is_buffer is false, this value is ignored (and should always be set to zero) */
48 
49  /** If this is a scalar parameter, then this is its type.
50  *
51  * If this is a buffer parameter, this is used to determine elem_size
52  * of the halide_buffer_t.
53  *
54  * Note that type.lanes() should always be 1 here. */
56 
57  /** The static size of the argument if known, or zero otherwise. */
58  size_t size = 0;
59 
60  /** The index of the first element of the argument when packed into a wider
61  * type, such as packing scalar floats into vec4 for GLSL. */
62  size_t packed_index = 0;
63 
64  /** For buffers, these two variables can be used to specify whether the
65  * buffer is read or written. By default, we assume that the argument
66  * buffer is read-write and set both flags. */
67  bool read = false;
68  bool write = false;
69 
70  /** Alignment information for integer parameters. */
72 
73  DeviceArgument() = default;
74 
75  DeviceArgument(const std::string &_name,
76  bool _is_buffer,
77  MemoryType _mem,
78  Type _type,
79  uint8_t _dimensions,
80  size_t _size = 0)
81  : name(_name),
82  is_buffer(_is_buffer),
83  memory_type(_mem),
84  dimensions(_dimensions),
85  type(_type),
86  size(_size),
87 
88  read(_is_buffer),
89  write(_is_buffer) {
90  }
91 };
92 
93 /** A Closure modified to inspect GPU-specific memory accesses, and
94  * produce a vector of DeviceArgument objects. */
95 class HostClosure : public Closure {
96 public:
97  HostClosure() = default;
98 
99  /** Get a description of the captured arguments. */
100  std::vector<DeviceArgument> arguments();
101 
102 protected:
104 
105  void visit(const For *loop) override;
106  void visit(const Call *op) override;
107 };
108 
109 } // namespace Internal
110 } // namespace Halide
111 
112 #endif
Halide::Internal::DeviceArgument::memory_type
MemoryType memory_type
If is_buffer == true and memory_type == GPUTexture, this argument should be passed and accessed throu...
Definition: DeviceArgument.h:43
uint8_t
unsigned __INT8_TYPE__ uint8_t
Definition: runtime_internal.h:29
Halide::Internal::For
A for loop.
Definition: IR.h:788
Halide::Internal::DeviceArgument::alignment
ModulusRemainder alignment
Alignment information for integer parameters.
Definition: DeviceArgument.h:71
Halide::Internal::HostClosure::arguments
std::vector< DeviceArgument > arguments()
Get a description of the captured arguments.
Halide::Internal::DeviceArgument::read
bool read
For buffers, these two variables can be used to specify whether the buffer is read or written.
Definition: DeviceArgument.h:67
Halide::Internal::HostClosure::visit
void visit(const For *loop) override
Halide::Internal::DeviceArgument::DeviceArgument
DeviceArgument(const std::string &_name, bool _is_buffer, MemoryType _mem, Type _type, uint8_t _dimensions, size_t _size=0)
Definition: DeviceArgument.h:75
Halide::Type
Types in the halide type system.
Definition: Type.h:276
Halide
This file defines the class FunctionDAG, which is our representation of a Halide pipeline,...
Definition: AbstractGenerator.h:19
Halide::Internal::Closure::visit
void visit(const Let *op) override
Halide::LinkageType::Internal
@ Internal
Not visible externally, similar to 'static' linkage in C.
Halide::Internal::DeviceArgument::packed_index
size_t packed_index
The index of the first element of the argument when packed into a wider type, such as packing scalar ...
Definition: DeviceArgument.h:62
Halide::Internal::DeviceArgument::size
size_t size
The static size of the argument if known, or zero otherwise.
Definition: DeviceArgument.h:58
Halide::Internal::DeviceArgument::type
Type type
If this is a scalar parameter, then this is its type.
Definition: DeviceArgument.h:55
Halide::Internal::DeviceArgument::is_buffer
bool is_buffer
An argument is either a primitive type (for parameters), or a buffer pointer.
Definition: DeviceArgument.h:37
Expr.h
Halide::Internal::Closure
A helper class to manage closures.
Definition: Closure.h:26
Halide::Internal::HostClosure::HostClosure
HostClosure()=default
Halide::Internal::Call
A function call.
Definition: IR.h:482
Halide::Internal::HostClosure
A Closure modified to inspect GPU-specific memory accesses, and produce a vector of DeviceArgument ob...
Definition: DeviceArgument.h:95
ModulusRemainder.h
Halide::Internal::DeviceArgument::DeviceArgument
DeviceArgument()=default
Closure.h
Halide::Internal::DeviceArgument::write
bool write
Definition: DeviceArgument.h:68
Halide::MemoryType::Auto
@ Auto
Let Halide select a storage type automatically.
Halide::Internal::DeviceArgument::name
std::string name
The name of the argument.
Definition: DeviceArgument.h:24
Halide::MemoryType
MemoryType
An enum describing different address spaces to be used with Func::store_in.
Definition: Expr.h:347
Halide::Internal::DeviceArgument::dimensions
uint8_t dimensions
If is_buffer is true, this is the dimensionality of the buffer.
Definition: DeviceArgument.h:47
Halide::Internal::ModulusRemainder
The result of modulus_remainder analysis.
Definition: ModulusRemainder.h:31
Halide::Internal::DeviceArgument
A DeviceArgument looks similar to an Halide::Argument, but has behavioral differences that make it sp...
Definition: DeviceArgument.h:22