1 //
2 // Copyright 2002 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 // Symbol table for parsing. The design principles and most of the functionality are documented in
7 // the header file.
8 //
9
10 #if defined(_MSC_VER)
11 # pragma warning(disable : 4718)
12 #endif
13
14 #include "compiler/translator/SymbolTable.h"
15
16 #include "angle_gl.h"
17 #include "compiler/translator/ImmutableString.h"
18 #include "compiler/translator/IntermNode.h"
19 #include "compiler/translator/StaticType.h"
20 #include "compiler/translator/util.h"
21
22 namespace sh
23 {
24
25 class TSymbolTable::TSymbolTableLevel
26 {
27 public:
28 TSymbolTableLevel() = default;
29
30 bool insert(TSymbol *symbol);
31
32 // Insert a function using its unmangled name as the key.
33 void insertUnmangled(TFunction *function);
34
35 TSymbol *find(const ImmutableString &name) const;
36
37 private:
38 using tLevel = TUnorderedMap<ImmutableString,
39 TSymbol *,
40 ImmutableString::FowlerNollVoHash<sizeof(size_t)>>;
41 using tLevelPair = const tLevel::value_type;
42 using tInsertResult = std::pair<tLevel::iterator, bool>;
43
44 tLevel level;
45 };
46
insert(TSymbol * symbol)47 bool TSymbolTable::TSymbolTableLevel::insert(TSymbol *symbol)
48 {
49 // returning true means symbol was added to the table
50 tInsertResult result = level.insert(tLevelPair(symbol->getMangledName(), symbol));
51 return result.second;
52 }
53
insertUnmangled(TFunction * function)54 void TSymbolTable::TSymbolTableLevel::insertUnmangled(TFunction *function)
55 {
56 level.insert(tLevelPair(function->name(), function));
57 }
58
find(const ImmutableString & name) const59 TSymbol *TSymbolTable::TSymbolTableLevel::find(const ImmutableString &name) const
60 {
61 tLevel::const_iterator it = level.find(name);
62 if (it == level.end())
63 return nullptr;
64 else
65 return (*it).second;
66 }
67
TSymbolTable()68 TSymbolTable::TSymbolTable()
69 : mGlobalInvariant(false),
70 mUniqueIdCounter(0),
71 mShaderType(GL_FRAGMENT_SHADER),
72 mGlInVariableWithArraySize(nullptr)
73 {}
74
75 TSymbolTable::~TSymbolTable() = default;
76
isEmpty() const77 bool TSymbolTable::isEmpty() const
78 {
79 return mTable.empty();
80 }
81
atGlobalLevel() const82 bool TSymbolTable::atGlobalLevel() const
83 {
84 return mTable.size() == 1u;
85 }
86
push()87 void TSymbolTable::push()
88 {
89 mTable.emplace_back(new TSymbolTableLevel);
90 mPrecisionStack.emplace_back(new PrecisionStackLevel);
91 }
92
pop()93 void TSymbolTable::pop()
94 {
95 mTable.pop_back();
96 mPrecisionStack.pop_back();
97 }
98
markFunctionHasPrototypeDeclaration(const ImmutableString & mangledName,bool * hadPrototypeDeclarationOut) const99 const TFunction *TSymbolTable::markFunctionHasPrototypeDeclaration(
100 const ImmutableString &mangledName,
101 bool *hadPrototypeDeclarationOut) const
102 {
103 TFunction *function = findUserDefinedFunction(mangledName);
104 *hadPrototypeDeclarationOut = function->hasPrototypeDeclaration();
105 function->setHasPrototypeDeclaration();
106 return function;
107 }
108
setFunctionParameterNamesFromDefinition(const TFunction * function,bool * wasDefinedOut) const109 const TFunction *TSymbolTable::setFunctionParameterNamesFromDefinition(const TFunction *function,
110 bool *wasDefinedOut) const
111 {
112 TFunction *firstDeclaration = findUserDefinedFunction(function->getMangledName());
113 ASSERT(firstDeclaration);
114 // Note: 'firstDeclaration' could be 'function' if this is the first time we've seen function as
115 // it would have just been put in the symbol table. Otherwise, we're looking up an earlier
116 // occurance.
117 if (function != firstDeclaration)
118 {
119 // The previous declaration should have the same parameters as the function definition
120 // (parameter names may differ).
121 firstDeclaration->shareParameters(*function);
122 }
123
124 *wasDefinedOut = firstDeclaration->isDefined();
125 firstDeclaration->setDefined();
126 return firstDeclaration;
127 }
128
setGlInArraySize(unsigned int inputArraySize)129 bool TSymbolTable::setGlInArraySize(unsigned int inputArraySize)
130 {
131 if (mGlInVariableWithArraySize)
132 {
133 return mGlInVariableWithArraySize->getType().getOutermostArraySize() == inputArraySize;
134 }
135 const TInterfaceBlock *glPerVertex = mVar_gl_PerVertex;
136 TType *glInType = new TType(glPerVertex, EvqPerVertexIn, TLayoutQualifier::Create());
137 glInType->makeArray(inputArraySize);
138 mGlInVariableWithArraySize =
139 new TVariable(this, ImmutableString("gl_in"), glInType, SymbolType::BuiltIn,
140 TExtension::EXT_geometry_shader);
141 return true;
142 }
143
getGlInVariableWithArraySize() const144 TVariable *TSymbolTable::getGlInVariableWithArraySize() const
145 {
146 return mGlInVariableWithArraySize;
147 }
148
gl_FragData() const149 const TVariable *TSymbolTable::gl_FragData() const
150 {
151 return mVar_gl_FragData;
152 }
153
gl_SecondaryFragDataEXT() const154 const TVariable *TSymbolTable::gl_SecondaryFragDataEXT() const
155 {
156 return mVar_gl_SecondaryFragDataEXT;
157 }
158
getOrCreateVariableMetadata(const TVariable & variable)159 TSymbolTable::VariableMetadata *TSymbolTable::getOrCreateVariableMetadata(const TVariable &variable)
160 {
161 int id = variable.uniqueId().get();
162 auto iter = mVariableMetadata.find(id);
163 if (iter == mVariableMetadata.end())
164 {
165 iter = mVariableMetadata.insert(std::make_pair(id, VariableMetadata())).first;
166 }
167 return &iter->second;
168 }
169
markStaticWrite(const TVariable & variable)170 void TSymbolTable::markStaticWrite(const TVariable &variable)
171 {
172 auto metadata = getOrCreateVariableMetadata(variable);
173 metadata->staticWrite = true;
174 }
175
markStaticRead(const TVariable & variable)176 void TSymbolTable::markStaticRead(const TVariable &variable)
177 {
178 auto metadata = getOrCreateVariableMetadata(variable);
179 metadata->staticRead = true;
180 }
181
isStaticallyUsed(const TVariable & variable) const182 bool TSymbolTable::isStaticallyUsed(const TVariable &variable) const
183 {
184 ASSERT(!variable.getConstPointer());
185 int id = variable.uniqueId().get();
186 auto iter = mVariableMetadata.find(id);
187 return iter != mVariableMetadata.end() && (iter->second.staticRead || iter->second.staticWrite);
188 }
189
addInvariantVarying(const TVariable & variable)190 void TSymbolTable::addInvariantVarying(const TVariable &variable)
191 {
192 ASSERT(atGlobalLevel());
193 auto metadata = getOrCreateVariableMetadata(variable);
194 metadata->invariant = true;
195 }
196
isVaryingInvariant(const TVariable & variable) const197 bool TSymbolTable::isVaryingInvariant(const TVariable &variable) const
198 {
199 ASSERT(atGlobalLevel());
200 if (mGlobalInvariant && (IsShaderOutput(variable.getType().getQualifier())))
201 {
202 return true;
203 }
204 int id = variable.uniqueId().get();
205 auto iter = mVariableMetadata.find(id);
206 return iter != mVariableMetadata.end() && iter->second.invariant;
207 }
208
setGlobalInvariant(bool invariant)209 void TSymbolTable::setGlobalInvariant(bool invariant)
210 {
211 ASSERT(atGlobalLevel());
212 mGlobalInvariant = invariant;
213 }
214
find(const ImmutableString & name,int shaderVersion) const215 const TSymbol *TSymbolTable::find(const ImmutableString &name, int shaderVersion) const
216 {
217 const TSymbol *userSymbol = findUserDefined(name);
218 if (userSymbol)
219 {
220 return userSymbol;
221 }
222
223 return findBuiltIn(name, shaderVersion);
224 }
225
findUserDefined(const ImmutableString & name) const226 const TSymbol *TSymbolTable::findUserDefined(const ImmutableString &name) const
227 {
228 int userDefinedLevel = static_cast<int>(mTable.size()) - 1;
229 while (userDefinedLevel >= 0)
230 {
231 const TSymbol *symbol = mTable[userDefinedLevel]->find(name);
232 if (symbol)
233 {
234 return symbol;
235 }
236 userDefinedLevel--;
237 }
238
239 return nullptr;
240 }
241
findUserDefinedFunction(const ImmutableString & name) const242 TFunction *TSymbolTable::findUserDefinedFunction(const ImmutableString &name) const
243 {
244 // User-defined functions are always declared at the global level.
245 ASSERT(!mTable.empty());
246 return static_cast<TFunction *>(mTable[0]->find(name));
247 }
248
findGlobal(const ImmutableString & name) const249 const TSymbol *TSymbolTable::findGlobal(const ImmutableString &name) const
250 {
251 ASSERT(!mTable.empty());
252 return mTable[0]->find(name);
253 }
254
findGlobalWithConversion(const std::vector<ImmutableString> & names) const255 const TSymbol *TSymbolTable::findGlobalWithConversion(
256 const std::vector<ImmutableString> &names) const
257 {
258 const TSymbol *target;
259 for (ImmutableString name : names)
260 {
261 target = findGlobal(name);
262 if (target != nullptr)
263 break;
264 }
265 return target;
266 }
267
findBuiltInWithConversion(const std::vector<ImmutableString> & names,int shaderVersion) const268 const TSymbol *TSymbolTable::findBuiltInWithConversion(const std::vector<ImmutableString> &names,
269 int shaderVersion) const
270 {
271 const TSymbol *target;
272 for (ImmutableString name : names)
273 {
274 target = findBuiltIn(name, shaderVersion);
275 if (target != nullptr)
276 break;
277 }
278 return target;
279 }
280
declare(TSymbol * symbol)281 bool TSymbolTable::declare(TSymbol *symbol)
282 {
283 ASSERT(!mTable.empty());
284 ASSERT(symbol->symbolType() == SymbolType::UserDefined);
285 ASSERT(!symbol->isFunction());
286 return mTable.back()->insert(symbol);
287 }
288
declareInternal(TSymbol * symbol)289 bool TSymbolTable::declareInternal(TSymbol *symbol)
290 {
291 ASSERT(!mTable.empty());
292 ASSERT(symbol->symbolType() == SymbolType::AngleInternal);
293 ASSERT(!symbol->isFunction());
294 return mTable.back()->insert(symbol);
295 }
296
declareUserDefinedFunction(TFunction * function,bool insertUnmangledName)297 void TSymbolTable::declareUserDefinedFunction(TFunction *function, bool insertUnmangledName)
298 {
299 ASSERT(!mTable.empty());
300 if (insertUnmangledName)
301 {
302 // Insert the unmangled name to detect potential future redefinition as a variable.
303 mTable[0]->insertUnmangled(function);
304 }
305 mTable[0]->insert(function);
306 }
307
setDefaultPrecision(TBasicType type,TPrecision prec)308 void TSymbolTable::setDefaultPrecision(TBasicType type, TPrecision prec)
309 {
310 int indexOfLastElement = static_cast<int>(mPrecisionStack.size()) - 1;
311 // Uses map operator [], overwrites the current value
312 (*mPrecisionStack[indexOfLastElement])[type] = prec;
313 }
314
getDefaultPrecision(TBasicType type) const315 TPrecision TSymbolTable::getDefaultPrecision(TBasicType type) const
316 {
317 if (!SupportsPrecision(type))
318 return EbpUndefined;
319
320 // unsigned integers use the same precision as signed
321 TBasicType baseType = (type == EbtUInt) ? EbtInt : type;
322
323 int level = static_cast<int>(mPrecisionStack.size()) - 1;
324 ASSERT(level >= 0); // Just to be safe. Should not happen.
325 // If we dont find anything we return this. Some types don't have predefined default precision.
326 TPrecision prec = EbpUndefined;
327 while (level >= 0)
328 {
329 PrecisionStackLevel::iterator it = mPrecisionStack[level]->find(baseType);
330 if (it != mPrecisionStack[level]->end())
331 {
332 prec = (*it).second;
333 break;
334 }
335 level--;
336 }
337 return prec;
338 }
339
clearCompilationResults()340 void TSymbolTable::clearCompilationResults()
341 {
342 mGlobalInvariant = false;
343 mUniqueIdCounter = kLastBuiltInId + 1;
344 mVariableMetadata.clear();
345 mGlInVariableWithArraySize = nullptr;
346
347 // User-defined scopes should have already been cleared when the compilation finished.
348 ASSERT(mTable.empty());
349 }
350
nextUniqueIdValue()351 int TSymbolTable::nextUniqueIdValue()
352 {
353 ASSERT(mUniqueIdCounter < std::numeric_limits<int>::max());
354 return ++mUniqueIdCounter;
355 }
356
initializeBuiltIns(sh::GLenum type,ShShaderSpec spec,const ShBuiltInResources & resources)357 void TSymbolTable::initializeBuiltIns(sh::GLenum type,
358 ShShaderSpec spec,
359 const ShBuiltInResources &resources)
360 {
361 mShaderType = type;
362 mResources = resources;
363
364 // We need just one precision stack level for predefined precisions.
365 mPrecisionStack.emplace_back(new PrecisionStackLevel);
366
367 if (IsDesktopGLSpec(spec))
368 {
369 setDefaultPrecision(EbtInt, EbpUndefined);
370 setDefaultPrecision(EbtFloat, EbpUndefined);
371 }
372 else
373 {
374 switch (type)
375 {
376 case GL_FRAGMENT_SHADER:
377 setDefaultPrecision(EbtInt, EbpMedium);
378 break;
379 case GL_VERTEX_SHADER:
380 case GL_COMPUTE_SHADER:
381 case GL_GEOMETRY_SHADER_EXT:
382 setDefaultPrecision(EbtInt, EbpHigh);
383 setDefaultPrecision(EbtFloat, EbpHigh);
384 break;
385 default:
386 UNREACHABLE();
387 }
388 }
389
390 // Set defaults for sampler types that have default precision, even those that are
391 // only available if an extension exists.
392 // New sampler types in ESSL3 don't have default precision. ESSL1 types do.
393 initSamplerDefaultPrecision(EbtSampler2D);
394 initSamplerDefaultPrecision(EbtSamplerCube);
395 // SamplerExternalOES is specified in the extension to have default precision.
396 initSamplerDefaultPrecision(EbtSamplerExternalOES);
397 // SamplerExternal2DY2YEXT is specified in the extension to have default precision.
398 initSamplerDefaultPrecision(EbtSamplerExternal2DY2YEXT);
399 // It isn't specified whether Sampler2DRect has default precision.
400 initSamplerDefaultPrecision(EbtSampler2DRect);
401
402 setDefaultPrecision(EbtAtomicCounter, EbpHigh);
403
404 initializeBuiltInVariables(type, spec, resources);
405 mUniqueIdCounter = kLastBuiltInId + 1;
406 }
407
initSamplerDefaultPrecision(TBasicType samplerType)408 void TSymbolTable::initSamplerDefaultPrecision(TBasicType samplerType)
409 {
410 ASSERT(samplerType >= EbtGuardSamplerBegin && samplerType <= EbtGuardSamplerEnd);
411 setDefaultPrecision(samplerType, EbpLow);
412 }
413
VariableMetadata()414 TSymbolTable::VariableMetadata::VariableMetadata()
415 : staticRead(false), staticWrite(false), invariant(false)
416 {}
417 } // namespace sh
418