1 //
2 // Copyright 2013 The ANGLE Project Authors. All rights reserved.
3 // Use of this source code is governed by a BSD-style license that can be
4 // found in the LICENSE file.
5 //
6 // ShaderVars.h:
7 // Types to represent GL variables (varyings, uniforms, etc)
8 //
9
10 #ifndef GLSLANG_SHADERVARS_H_
11 #define GLSLANG_SHADERVARS_H_
12
13 #include <algorithm>
14 #include <array>
15 #include <string>
16 #include <vector>
17
18 // This type is defined here to simplify ANGLE's integration with glslang for SPIRv.
19 using ShCompileOptions = uint64_t;
20
21 namespace sh
22 {
23 // GLenum alias
24 typedef unsigned int GLenum;
25
26 // Varying interpolation qualifier, see section 4.3.9 of the ESSL 3.00.4 spec
27 enum InterpolationType
28 {
29 INTERPOLATION_SMOOTH,
30 INTERPOLATION_CENTROID,
31 INTERPOLATION_SAMPLE,
32 INTERPOLATION_FLAT,
33 INTERPOLATION_NOPERSPECTIVE
34 };
35
36 // Validate link & SSO consistency of interpolation qualifiers
37 bool InterpolationTypesMatch(InterpolationType a, InterpolationType b);
38
39 // Uniform block layout qualifier, see section 4.3.8.3 of the ESSL 3.00.4 spec
40 enum BlockLayoutType
41 {
42 BLOCKLAYOUT_STANDARD,
43 BLOCKLAYOUT_STD140 = BLOCKLAYOUT_STANDARD,
44 BLOCKLAYOUT_STD430, // Shader storage block layout qualifier
45 BLOCKLAYOUT_PACKED,
46 BLOCKLAYOUT_SHARED
47 };
48
49 // Interface Blocks, see section 4.3.9 of the ESSL 3.10 spec
50 enum class BlockType
51 {
52 BLOCK_UNIFORM,
53 BLOCK_BUFFER,
54 };
55
56 // Base class for all variables defined in shaders, including Varyings, Uniforms, etc
57 // Note: we must override the copy constructor and assignment operator so we can
58 // work around excessive GCC binary bloating:
59 // See https://code.google.com/p/angleproject/issues/detail?id=697
60 struct ShaderVariable
61 {
62 ShaderVariable();
63 ShaderVariable(GLenum typeIn);
64 ShaderVariable(GLenum typeIn, unsigned int arraySizeIn);
65 ~ShaderVariable();
66 ShaderVariable(const ShaderVariable &other);
67 ShaderVariable &operator=(const ShaderVariable &other);
68 bool operator==(const ShaderVariable &other) const;
69 bool operator!=(const ShaderVariable &other) const { return !operator==(other); }
70
isArrayOfArraysShaderVariable71 bool isArrayOfArrays() const { return arraySizes.size() >= 2u; }
isArrayShaderVariable72 bool isArray() const { return !arraySizes.empty(); }
73 unsigned int getArraySizeProduct() const;
74 // Return the inner array size product.
75 // For example, if there's a variable declared as size 3 array of size 4 array of size 5 array
76 // of int:
77 // int a[3][4][5];
78 // then getInnerArraySizeProduct of a would be 4*5.
79 unsigned int getInnerArraySizeProduct() const;
80
81 // Array size 0 means not an array when passed to or returned from these functions.
82 // Note that setArraySize() is deprecated and should not be used inside ANGLE.
getOutermostArraySizeShaderVariable83 unsigned int getOutermostArraySize() const { return isArray() ? arraySizes.back() : 0; }
84 void setArraySize(unsigned int size);
85
86 // Turn this ShaderVariable from an array into a specific element in that array. Will update
87 // flattenedOffsetInParentArrays.
88 void indexIntoArray(unsigned int arrayIndex);
89
90 // Get the nth nested array size from the top. Caller is responsible for range checking
91 // arrayNestingIndex.
92 unsigned int getNestedArraySize(unsigned int arrayNestingIndex) const;
93
94 // This function should only be used with variables that are of a basic type or an array of a
95 // basic type. Shader interface variables that are enumerated according to rules in GLES 3.1
96 // spec section 7.3.1.1 page 77 are fine. For those variables the return value should match the
97 // ARRAY_SIZE value that can be queried through the API.
98 unsigned int getBasicTypeElementCount() const;
99
100 unsigned int getExternalSize() const;
101
isStructShaderVariable102 bool isStruct() const { return !fields.empty(); }
getStructNameShaderVariable103 const std::string &getStructName() const { return structOrBlockName; }
setStructNameShaderVariable104 void setStructName(const std::string &newName) { structOrBlockName = newName; }
105
106 // All of the shader's variables are described using nested data
107 // structures. This is needed in order to disambiguate similar looking
108 // types, such as two structs containing the same fields, but in
109 // different orders. "findInfoByMappedName" provides an easy query for
110 // users to dive into the data structure and fetch the unique variable
111 // instance corresponding to a dereferencing chain of the top-level
112 // variable.
113 // Given a mapped name like 'a[0].b.c[0]', return the ShaderVariable
114 // that defines 'c' in |leafVar|, and the original name 'A[0].B.C[0]'
115 // in |originalName|, based on the assumption that |this| defines 'a'.
116 // If no match is found, return false.
117 bool findInfoByMappedName(const std::string &mappedFullName,
118 const ShaderVariable **leafVar,
119 std::string *originalFullName) const;
120
121 // Find the child field which matches 'fullName' == var.name + "." + field.name.
122 // Return nullptr if not found.
123 const sh::ShaderVariable *findField(const std::string &fullName, uint32_t *fieldIndexOut) const;
124
125 bool isBuiltIn() const;
126 bool isEmulatedBuiltIn() const;
127
128 // Offset of this variable in parent arrays. In case the parent is an array of arrays, the
129 // offset is outerArrayElement * innerArraySize + innerArrayElement.
130 // For example, if there's a variable declared as size 3 array of size 4 array of int:
131 // int a[3][4];
132 // then the flattenedOffsetInParentArrays of a[2] would be 2.
133 // and flattenedOffsetInParentArrays of a[2][1] would be 2*4 + 1 = 9.
parentArrayIndexShaderVariable134 int parentArrayIndex() const
135 {
136 return hasParentArrayIndex() ? flattenedOffsetInParentArrays : 0;
137 }
138
getFlattenedOffsetInParentArraysShaderVariable139 int getFlattenedOffsetInParentArrays() const { return flattenedOffsetInParentArrays; }
setParentArrayIndexShaderVariable140 void setParentArrayIndex(int indexIn) { flattenedOffsetInParentArrays = indexIn; }
141
hasParentArrayIndexShaderVariable142 bool hasParentArrayIndex() const { return flattenedOffsetInParentArrays != -1; }
143
144 void resetEffectiveLocation();
145 void updateEffectiveLocation(const sh::ShaderVariable &parent);
146
147 // Decide whether two uniforms are the same at shader link time,
148 // assuming they are from consecutive shader stages.
149 // GLSL ES Spec 3.00.3, section 4.3.5.
150 // GLSL ES Spec 3.10.4, section 4.4.5
151 bool isSameUniformAtLinkTime(const ShaderVariable &other) const;
152
153 // InterfaceBlockField
154 // Decide whether two InterfaceBlock fields are the same at shader
155 // link time, assuming they are from consecutive shader stages.
156 // See GLSL ES Spec 3.00.3, sec 4.3.7.
157 bool isSameInterfaceBlockFieldAtLinkTime(const ShaderVariable &other) const;
158
159 // Decide whether two varyings are the same at shader link time,
160 // assuming they are from consecutive shader stages.
161 // Invariance needs to match only in ESSL1. Relevant spec sections:
162 // GLSL ES 3.00.4, sections 4.6.1 and 4.3.9.
163 // GLSL ES 1.00.17, section 4.6.4.
164 bool isSameVaryingAtLinkTime(const ShaderVariable &other, int shaderVersion) const;
165 // Deprecated version of isSameVaryingAtLinkTime, which assumes ESSL1.
166 bool isSameVaryingAtLinkTime(const ShaderVariable &other) const;
167
168 // Shader I/O blocks may match by block name or instance, based on whether both stages have an
169 // instance name or not.
170 bool isSameNameAtLinkTime(const ShaderVariable &other) const;
171
172 // NOTE: When adding new members, the following functions also need to be updated:
173 // gl::WriteShaderVar(BinaryOutputStream *stream, const sh::ShaderVariable &var)
174 // gl::LoadShaderVar(BinaryInputStream *stream, sh::ShaderVariable *var)
175
176 GLenum type;
177 GLenum precision;
178 std::string name;
179 std::string mappedName;
180
181 // Used to make an array type. Outermost array size is stored at the end of the vector.
182 std::vector<unsigned int> arraySizes;
183
184 // Static use means that the variable is accessed somewhere in the shader source.
185 bool staticUse;
186 // A variable is active unless the compiler determined that it is not accessed by the shader.
187 // All active variables are statically used, but not all statically used variables are
188 // necessarily active. GLES 3.0.5 section 2.12.6. GLES 3.1 section 7.3.1.
189 bool active;
190 std::vector<ShaderVariable> fields;
191 // structOrBlockName is used for:
192 // - varyings of struct type, in which case it contains the struct name.
193 // - shader I/O blocks, in which case it contains the block name.
194 std::string structOrBlockName;
195 std::string mappedStructOrBlockName;
196
197 // Only applies to interface block fields. Kept here for simplicity.
198 bool isRowMajorLayout;
199
200 // VariableWithLocation
201 int location;
202
203 // The location of inputs or outputs without location layout quailifer will be updated to '-1'.
204 // GLES Spec 3.1, Section 7.3. PROGRAM OBJECTS
205 // Not all active variables are assigned valid locations;
206 // the following variables will have an effective location of -1:
207 bool hasImplicitLocation;
208
209 // Uniform
210 int binding;
211 GLenum imageUnitFormat;
212 int offset;
213 bool readonly;
214 bool writeonly;
215
216 // From EXT_shader_framebuffer_fetch
217 bool isFragmentInOut;
218
219 // OutputVariable
220 // From EXT_blend_func_extended.
221 int index;
222
223 // From EXT_YUV_target
224 bool yuv;
225
226 // Varying
227 InterpolationType interpolation;
228 bool isInvariant;
229 bool isShaderIOBlock;
230 bool isPatch;
231
232 // If the variable is a sampler that has ever been statically used with texelFetch
233 bool texelFetchStaticUse;
234
235 protected:
236 bool isSameVariableAtLinkTime(const ShaderVariable &other,
237 bool matchPrecision,
238 bool matchName) const;
239
240 // NOTE: When adding new members, the following functions also need to be updated:
241 // gl::WriteShaderVar(BinaryOutputStream *stream, const sh::ShaderVariable &var)
242 // gl::LoadShaderVar(BinaryInputStream *stream, sh::ShaderVariable *var)
243
244 int flattenedOffsetInParentArrays;
245 };
246
247 // TODO: anglebug.com/3899
248 // For backwards compatibility for other codebases (e.g., chromium/src/gpu/command_buffer/service)
249 using Uniform = ShaderVariable;
250 using Attribute = ShaderVariable;
251 using OutputVariable = ShaderVariable;
252 using InterfaceBlockField = ShaderVariable;
253 using Varying = ShaderVariable;
254
255 struct InterfaceBlock
256 {
257 InterfaceBlock();
258 ~InterfaceBlock();
259 InterfaceBlock(const InterfaceBlock &other);
260 InterfaceBlock &operator=(const InterfaceBlock &other);
261
262 // Fields from blocks with non-empty instance names are prefixed with the block name.
263 std::string fieldPrefix() const;
264 std::string fieldMappedPrefix() const;
265
266 // Decide whether two interface blocks are the same at shader link time.
267 bool isSameInterfaceBlockAtLinkTime(const InterfaceBlock &other) const;
268
269 bool isBuiltIn() const;
270
isArrayInterfaceBlock271 bool isArray() const { return arraySize > 0; }
elementCountInterfaceBlock272 unsigned int elementCount() const { return std::max(1u, arraySize); }
273
274 std::string name;
275 std::string mappedName;
276 std::string instanceName;
277 unsigned int arraySize;
278 BlockLayoutType layout;
279
280 // Deprecated. Matrix packing should only be queried from individual fields of the block.
281 // TODO(oetuaho): Remove this once it is no longer used in Chromium.
282 bool isRowMajorLayout;
283
284 int binding;
285 bool staticUse;
286 bool active;
287 BlockType blockType;
288 std::vector<ShaderVariable> fields;
289 };
290
291 struct WorkGroupSize
292 {
293 // Must have a trivial default constructor since it is used in YYSTYPE.
294 inline WorkGroupSize() = default;
295 inline explicit constexpr WorkGroupSize(int initialSize);
296
297 void fill(int fillValue);
298 void setLocalSize(int localSizeX, int localSizeY, int localSizeZ);
299
300 int &operator[](size_t index);
301 int operator[](size_t index) const;
302 size_t size() const;
303
304 // Checks whether two work group size declarations match.
305 // Two work group size declarations are the same if the explicitly specified elements are the
306 // same or if one of them is specified as one and the other one is not specified
307 bool isWorkGroupSizeMatching(const WorkGroupSize &right) const;
308
309 // Checks whether any of the values are set.
310 bool isAnyValueSet() const;
311
312 // Checks whether all of the values are set.
313 bool isDeclared() const;
314
315 // Checks whether either all of the values are set, or none of them are.
316 bool isLocalSizeValid() const;
317
318 int localSizeQualifiers[3];
319 };
320
WorkGroupSize(int initialSize)321 inline constexpr WorkGroupSize::WorkGroupSize(int initialSize)
322 : localSizeQualifiers{initialSize, initialSize, initialSize}
323 {}
324
325 } // namespace sh
326
327 #endif // GLSLANG_SHADERVARS_H_
328