1 // Copyright 2016 The SwiftShader Authors. All Rights Reserved.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //    http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 #ifndef _SYMBOL_TABLE_INCLUDED_
16 #define _SYMBOL_TABLE_INCLUDED_
17 
18 //
19 // Symbol table for parsing.  Has these design characteristics:
20 //
21 // * Same symbol table can be used to compile many shaders, to preserve
22 //   effort of creating and loading with the large numbers of built-in
23 //   symbols.
24 //
25 // * Name mangling will be used to give each function a unique name
26 //   so that symbol table lookups are never ambiguous.  This allows
27 //   a simpler symbol table structure.
28 //
29 // * Pushing and popping of scope, so symbol table will really be a stack
30 //   of symbol tables.  Searched from the top, with new inserts going into
31 //   the top.
32 //
33 // * Constants:  Compile time constant symbols will keep their values
34 //   in the symbol table.  The parser can substitute constants at parse
35 //   time, including doing constant folding and constant propagation.
36 //
37 // * No temporaries:  Temporaries made from operations (+, --, .xy, etc.)
38 //   are tracked in the intermediate representation, not the symbol table.
39 //
40 
41 #ifndef __ANDROID__
42 #include <assert.h>
43 #else
44 #include "../../Common/DebugAndroid.hpp"
45 #endif
46 
47 #include "InfoSink.h"
48 #include "intermediate.h"
49 #include <set>
50 
51 //
52 // Symbol base class.  (Can build functions or variables out of these...)
53 //
54 class TSymbol
55 {
56 public:
57 	POOL_ALLOCATOR_NEW_DELETE();
TSymbol(const TString * n)58 	TSymbol(const TString *n) :  name(n) { }
~TSymbol()59 	virtual ~TSymbol() { /* don't delete name, it's from the pool */ }
60 
getName()61 	const TString& getName() const { return *name; }
getMangledName()62 	virtual const TString& getMangledName() const { return getName(); }
isFunction()63 	virtual bool isFunction() const { return false; }
isVariable()64 	virtual bool isVariable() const { return false; }
setUniqueId(int id)65 	void setUniqueId(int id) { uniqueId = id; }
getUniqueId()66 	int getUniqueId() const { return uniqueId; }
67 	TSymbol(const TSymbol&);
68 
69 protected:
70 	const TString *name;
71 	unsigned int uniqueId;      // For real comparing during code generation
72 };
73 
74 //
75 // Variable class, meaning a symbol that's not a function.
76 //
77 // There could be a separate class heirarchy for Constant variables;
78 // Only one of int, bool, or float, (or none) is correct for
79 // any particular use, but it's easy to do this way, and doesn't
80 // seem worth having separate classes, and "getConst" can't simply return
81 // different values for different types polymorphically, so this is
82 // just simple and pragmatic.
83 //
84 class TVariable : public TSymbol
85 {
86 public:
TSymbol(name)87 	TVariable(const TString *name, const TType& t, bool uT = false ) : TSymbol(name), type(t), userType(uT), unionArray(0), arrayInformationType(0) { }
~TVariable()88 	virtual ~TVariable() { }
isVariable()89 	virtual bool isVariable() const { return true; }
getType()90 	TType& getType() { return type; }
getType()91 	const TType& getType() const { return type; }
isUserType()92 	bool isUserType() const { return userType; }
setQualifier(TQualifier qualifier)93 	void setQualifier(TQualifier qualifier) { type.setQualifier(qualifier); }
updateArrayInformationType(TType * t)94 	void updateArrayInformationType(TType *t) { arrayInformationType = t; }
getArrayInformationType()95 	TType* getArrayInformationType() { return arrayInformationType; }
96 
getConstPointer()97 	ConstantUnion* getConstPointer()
98 	{
99 		if (!unionArray)
100 			unionArray = new ConstantUnion[type.getObjectSize()];
101 
102 		return unionArray;
103 	}
104 
getConstPointer()105 	ConstantUnion* getConstPointer() const { return unionArray; }
isConstant()106 	bool isConstant() const { return unionArray != nullptr; }
107 
shareConstPointer(ConstantUnion * constArray)108 	void shareConstPointer( ConstantUnion *constArray)
109 	{
110 		if (unionArray == constArray)
111 			return;
112 
113 		delete[] unionArray;
114 		unionArray = constArray;
115 	}
116 
117 protected:
118 	TType type;
119 	bool userType;
120 	// we are assuming that Pool Allocator will free the memory allocated to unionArray
121 	// when this object is destroyed
122 	ConstantUnion *unionArray;
123 	TType *arrayInformationType;  // this is used for updating maxArraySize in all the references to a given symbol
124 };
125 
126 //
127 // The function sub-class of symbols and the parser will need to
128 // share this definition of a function parameter.
129 //
130 struct TParameter
131 {
132 	TString *name;
133 	TType *type;
134 };
135 
136 //
137 // The function sub-class of a symbol.
138 //
139 class TFunction : public TSymbol
140 {
141 public:
TFunction(TOperator o)142 	TFunction(TOperator o) :
143 		TSymbol(0),
144 		returnType(TType(EbtVoid, EbpUndefined)),
145 		op(o),
146 		defined(false),
147 		prototypeDeclaration(false) { }
148 	TFunction(const TString *name, const TType& retType, TOperator tOp = EOpNull, const char *ext = "") :
TSymbol(name)149 		TSymbol(name),
150 		returnType(retType),
151 		mangledName(TFunction::mangleName(*name)),
152 		op(tOp),
153 		extension(ext),
154 		defined(false),
155 		prototypeDeclaration(false) { }
156 	virtual ~TFunction();
isFunction()157 	virtual bool isFunction() const { return true; }
158 
mangleName(const TString & name)159 	static TString mangleName(const TString& name) { return name + '('; }
unmangleName(const TString & mangledName)160 	static TString unmangleName(const TString& mangledName)
161 	{
162 		return TString(mangledName.c_str(), mangledName.find_first_of('('));
163 	}
164 
addParameter(TParameter & p)165 	void addParameter(TParameter& p)
166 	{
167 		parameters.push_back(p);
168 		mangledName = mangledName + p.type->getMangledName();
169 	}
170 
getMangledName()171 	const TString& getMangledName() const { return mangledName; }
getReturnType()172 	const TType& getReturnType() const { return returnType; }
173 
getBuiltInOp()174 	TOperator getBuiltInOp() const { return op; }
getExtension()175 	const TString& getExtension() const { return extension; }
176 
setDefined()177 	void setDefined() { defined = true; }
isDefined()178 	bool isDefined() { return defined; }
setHasPrototypeDeclaration()179 	void setHasPrototypeDeclaration() { prototypeDeclaration = true; }
hasPrototypeDeclaration()180 	bool hasPrototypeDeclaration() const { return prototypeDeclaration; }
181 
getParamCount()182 	size_t getParamCount() const { return parameters.size(); }
getParam(int i)183 	const TParameter& getParam(int i) const { return parameters[i]; }
184 
185 protected:
186 	typedef TVector<TParameter> TParamList;
187 	TParamList parameters;
188 	TType returnType;
189 	TString mangledName;
190 	TOperator op;
191 	TString extension;
192 	bool defined;
193 	bool prototypeDeclaration;
194 };
195 
196 
197 class TSymbolTableLevel
198 {
199 public:
200 	typedef TMap<TString, TSymbol*> tLevel;
201 	typedef tLevel::const_iterator const_iterator;
202 	typedef const tLevel::value_type tLevelPair;
203 	typedef std::pair<tLevel::iterator, bool> tInsertResult;
204 
205 	POOL_ALLOCATOR_NEW_DELETE();
TSymbolTableLevel()206 	TSymbolTableLevel() { }
207 	~TSymbolTableLevel();
208 
209 	bool insert(TSymbol *symbol);
210 
211 	// Insert a function using its unmangled name as the key.
212 	bool insertUnmangled(TFunction *function);
213 
214 	TSymbol *find(const TString &name) const;
215 
nextUniqueId()216 	static int nextUniqueId()
217 	{
218 		return ++uniqueId;
219 	}
220 
221 protected:
222 	tLevel level;
223 	static int uniqueId;     // for unique identification in code generation
224 };
225 
226 enum ESymbolLevel
227 {
228 	COMMON_BUILTINS,
229 	ESSL1_BUILTINS,
230 	ESSL3_BUILTINS,
231 	LAST_BUILTIN_LEVEL = ESSL3_BUILTINS,
232 	GLOBAL_LEVEL
233 };
234 
IsGenType(const TType * type)235 inline bool IsGenType(const TType *type)
236 {
237 	if(type)
238 	{
239 		TBasicType basicType = type->getBasicType();
240 		return basicType == EbtGenType || basicType == EbtGenIType || basicType == EbtGenUType || basicType == EbtGenBType;
241 	}
242 
243 	return false;
244 }
245 
IsVecType(const TType * type)246 inline bool IsVecType(const TType *type)
247 {
248 	if(type)
249 	{
250 		TBasicType basicType = type->getBasicType();
251 		return basicType == EbtVec || basicType == EbtIVec || basicType == EbtUVec || basicType == EbtBVec;
252 	}
253 
254 	return false;
255 }
256 
GenType(TType * type,int size)257 inline TType *GenType(TType *type, int size)
258 {
259 	ASSERT(size >= 1 && size <= 4);
260 
261 	if(!type)
262 	{
263 		return nullptr;
264 	}
265 
266 	ASSERT(!IsVecType(type));
267 
268 	switch(type->getBasicType())
269 	{
270 	case EbtGenType:  return new TType(EbtFloat, size);
271 	case EbtGenIType: return new TType(EbtInt, size);
272 	case EbtGenUType: return new TType(EbtUInt, size);
273 	case EbtGenBType: return new TType(EbtBool, size);
274 	default: return type;
275 	}
276 }
277 
VecType(TType * type,int size)278 inline TType *VecType(TType *type, int size)
279 {
280 	ASSERT(size >= 2 && size <= 4);
281 
282 	if(!type)
283 	{
284 		return nullptr;
285 	}
286 
287 	ASSERT(!IsGenType(type));
288 
289 	switch(type->getBasicType())
290 	{
291 	case EbtVec:  return new TType(EbtFloat, size);
292 	case EbtIVec: return new TType(EbtInt, size);
293 	case EbtUVec: return new TType(EbtUInt, size);
294 	case EbtBVec: return new TType(EbtBool, size);
295 	default: return type;
296 	}
297 }
298 
299 class TSymbolTable
300 {
301 public:
TSymbolTable()302 	TSymbolTable()
303 		: mGlobalInvariant(false)
304 	{
305 		//
306 		// The symbol table cannot be used until push() is called, but
307 		// the lack of an initial call to push() can be used to detect
308 		// that the symbol table has not been preloaded with built-ins.
309 		//
310 	}
311 
~TSymbolTable()312 	~TSymbolTable()
313 	{
314 		while(currentLevel() > LAST_BUILTIN_LEVEL)
315 		{
316 			pop();
317 		}
318 	}
319 
isEmpty()320 	bool isEmpty() { return table.empty(); }
atBuiltInLevel()321 	bool atBuiltInLevel() { return currentLevel() <= LAST_BUILTIN_LEVEL; }
atGlobalLevel()322 	bool atGlobalLevel() { return currentLevel() <= GLOBAL_LEVEL; }
push()323 	void push()
324 	{
325 		table.push_back(new TSymbolTableLevel);
326 		precisionStack.push_back( PrecisionStackLevel() );
327 	}
328 
pop()329 	void pop()
330 	{
331 		delete table[currentLevel()];
332 		table.pop_back();
333 		precisionStack.pop_back();
334 	}
335 
declare(TSymbol * symbol)336 	bool declare(TSymbol *symbol)
337 	{
338 		return insert(currentLevel(), symbol);
339 	}
340 
insert(ESymbolLevel level,TSymbol * symbol)341 	bool insert(ESymbolLevel level, TSymbol *symbol)
342 	{
343 		return table[level]->insert(symbol);
344 	}
345 
insertConstInt(ESymbolLevel level,const char * name,int value)346 	bool insertConstInt(ESymbolLevel level, const char *name, int value)
347 	{
348 		TVariable *constant = new TVariable(NewPoolTString(name), TType(EbtInt, EbpUndefined, EvqConstExpr, 1));
349 		constant->getConstPointer()->setIConst(value);
350 		return insert(level, constant);
351 	}
352 
353 	void insertBuiltIn(ESymbolLevel level, TOperator op, const char *ext, TType *rvalue, const char *name, TType *ptype1, TType *ptype2 = 0, TType *ptype3 = 0, TType *ptype4 = 0, TType *ptype5 = 0)
354 	{
355 		if(ptype1->getBasicType() == EbtGSampler2D)
356 		{
357 			insertUnmangledBuiltIn(name);
358 			bool gvec4 = (rvalue->getBasicType() == EbtGVec4);
359 			insertBuiltIn(level, gvec4 ? new TType(EbtFloat, 4) : rvalue, name, new TType(EbtSampler2D), ptype2, ptype3, ptype4, ptype5);
360 			insertBuiltIn(level, gvec4 ? new TType(EbtInt, 4) : rvalue, name, new TType(EbtISampler2D), ptype2, ptype3, ptype4, ptype5);
361 			insertBuiltIn(level, gvec4 ? new TType(EbtUInt, 4) : rvalue, name, new TType(EbtUSampler2D), ptype2, ptype3, ptype4, ptype5);
362 		}
363 		else if(ptype1->getBasicType() == EbtGSampler3D)
364 		{
365 			insertUnmangledBuiltIn(name);
366 			bool gvec4 = (rvalue->getBasicType() == EbtGVec4);
367 			insertBuiltIn(level, gvec4 ? new TType(EbtFloat, 4) : rvalue, name, new TType(EbtSampler3D), ptype2, ptype3, ptype4, ptype5);
368 			insertBuiltIn(level, gvec4 ? new TType(EbtInt, 4) : rvalue, name, new TType(EbtISampler3D), ptype2, ptype3, ptype4, ptype5);
369 			insertBuiltIn(level, gvec4 ? new TType(EbtUInt, 4) : rvalue, name, new TType(EbtUSampler3D), ptype2, ptype3, ptype4, ptype5);
370 		}
371 		else if(ptype1->getBasicType() == EbtGSamplerCube)
372 		{
373 			insertUnmangledBuiltIn(name);
374 			bool gvec4 = (rvalue->getBasicType() == EbtGVec4);
375 			insertBuiltIn(level, gvec4 ? new TType(EbtFloat, 4) : rvalue, name, new TType(EbtSamplerCube), ptype2, ptype3, ptype4, ptype5);
376 			insertBuiltIn(level, gvec4 ? new TType(EbtInt, 4) : rvalue, name, new TType(EbtISamplerCube), ptype2, ptype3, ptype4, ptype5);
377 			insertBuiltIn(level, gvec4 ? new TType(EbtUInt, 4) : rvalue, name, new TType(EbtUSamplerCube), ptype2, ptype3, ptype4, ptype5);
378 		}
379 		else if(ptype1->getBasicType() == EbtGSampler2DArray)
380 		{
381 			insertUnmangledBuiltIn(name);
382 			bool gvec4 = (rvalue->getBasicType() == EbtGVec4);
383 			insertBuiltIn(level, gvec4 ? new TType(EbtFloat, 4) : rvalue, name, new TType(EbtSampler2DArray), ptype2, ptype3, ptype4, ptype5);
384 			insertBuiltIn(level, gvec4 ? new TType(EbtInt, 4) : rvalue, name, new TType(EbtISampler2DArray), ptype2, ptype3, ptype4, ptype5);
385 			insertBuiltIn(level, gvec4 ? new TType(EbtUInt, 4) : rvalue, name, new TType(EbtUSampler2DArray), ptype2, ptype3, ptype4, ptype5);
386 		}
387 		else if(IsGenType(rvalue) || IsGenType(ptype1) || IsGenType(ptype2) || IsGenType(ptype3))
388 		{
389 			ASSERT(!ptype4);
390 			insertUnmangledBuiltIn(name);
391 			insertBuiltIn(level, op, ext, GenType(rvalue, 1), name, GenType(ptype1, 1), GenType(ptype2, 1), GenType(ptype3, 1));
392 			insertBuiltIn(level, op, ext, GenType(rvalue, 2), name, GenType(ptype1, 2), GenType(ptype2, 2), GenType(ptype3, 2));
393 			insertBuiltIn(level, op, ext, GenType(rvalue, 3), name, GenType(ptype1, 3), GenType(ptype2, 3), GenType(ptype3, 3));
394 			insertBuiltIn(level, op, ext, GenType(rvalue, 4), name, GenType(ptype1, 4), GenType(ptype2, 4), GenType(ptype3, 4));
395 		}
396 		else if(IsVecType(rvalue) || IsVecType(ptype1) || IsVecType(ptype2) || IsVecType(ptype3))
397 		{
398 			ASSERT(!ptype4);
399 			insertUnmangledBuiltIn(name);
400 			insertBuiltIn(level, op, ext, VecType(rvalue, 2), name, VecType(ptype1, 2), VecType(ptype2, 2), VecType(ptype3, 2));
401 			insertBuiltIn(level, op, ext, VecType(rvalue, 3), name, VecType(ptype1, 3), VecType(ptype2, 3), VecType(ptype3, 3));
402 			insertBuiltIn(level, op, ext, VecType(rvalue, 4), name, VecType(ptype1, 4), VecType(ptype2, 4), VecType(ptype3, 4));
403 		}
404 		else
405 		{
406 			TFunction *function = new TFunction(NewPoolTString(name), *rvalue, op, ext);
407 
408 			TParameter param1 = {0, ptype1};
409 			function->addParameter(param1);
410 
411 			if(ptype2)
412 			{
413 				TParameter param2 = {0, ptype2};
414 				function->addParameter(param2);
415 			}
416 
417 			if(ptype3)
418 			{
419 				TParameter param3 = {0, ptype3};
420 				function->addParameter(param3);
421 			}
422 
423 			if(ptype4)
424 			{
425 				TParameter param4 = {0, ptype4};
426 				function->addParameter(param4);
427 			}
428 
429 			if(ptype5)
430 			{
431 				TParameter param5 = {0, ptype5};
432 				function->addParameter(param5);
433 			}
434 
435 			ASSERT(hasUnmangledBuiltIn(name));
436 			insert(level, function);
437 		}
438 	}
439 
440 	void insertBuiltIn(ESymbolLevel level, TOperator op, TType *rvalue, const char *name, TType *ptype1, TType *ptype2 = 0, TType *ptype3 = 0, TType *ptype4 = 0, TType *ptype5 = 0)
441 	{
442 		insertUnmangledBuiltIn(name);
443 		insertBuiltIn(level, op, "", rvalue, name, ptype1, ptype2, ptype3, ptype4, ptype5);
444 	}
445 
446 	void insertBuiltIn(ESymbolLevel level, TType *rvalue, const char *name, TType *ptype1, TType *ptype2 = 0, TType *ptype3 = 0, TType *ptype4 = 0, TType *ptype5 = 0)
447 	{
448 		insertUnmangledBuiltIn(name);
449 		insertBuiltIn(level, EOpNull, rvalue, name, ptype1, ptype2, ptype3, ptype4, ptype5);
450 	}
451 
452 	TSymbol *find(const TString &name, int shaderVersion, bool *builtIn = nullptr, bool *sameScope = nullptr) const;
453 	TSymbol *findBuiltIn(const TString &name, int shaderVersion) const;
454 
getOuterLevel()455 	TSymbolTableLevel *getOuterLevel() const
456 	{
457 		assert(currentLevel() >= 1);
458 		return table[currentLevel() - 1];
459 	}
460 
setDefaultPrecision(const TPublicType & type,TPrecision prec)461 	bool setDefaultPrecision(const TPublicType &type, TPrecision prec)
462 	{
463 		if (IsSampler(type.type))
464 			return true;  // Skip sampler types for the time being
465 		if (type.type != EbtFloat && type.type != EbtInt)
466 			return false; // Only set default precision for int/float
467 		if (type.primarySize > 1 || type.secondarySize > 1 || type.array)
468 			return false; // Not allowed to set for aggregate types
469 		int indexOfLastElement = static_cast<int>(precisionStack.size()) - 1;
470 		precisionStack[indexOfLastElement][type.type] = prec; // Uses map operator [], overwrites the current value
471 		return true;
472 	}
473 
474 	// Searches down the precisionStack for a precision qualifier for the specified TBasicType
getDefaultPrecision(TBasicType type)475 	TPrecision getDefaultPrecision( TBasicType type)
476 	{
477 		// unsigned integers use the same precision as signed
478 		if (type == EbtUInt) type = EbtInt;
479 
480 		if( type != EbtFloat && type != EbtInt ) return EbpUndefined;
481 		int level = static_cast<int>(precisionStack.size()) - 1;
482 		assert( level >= 0); // Just to be safe. Should not happen.
483 		PrecisionStackLevel::iterator it;
484 		TPrecision prec = EbpUndefined; // If we dont find anything we return this. Should we error check this?
485 		while( level >= 0 ){
486 			it = precisionStack[level].find( type );
487 			if( it != precisionStack[level].end() ){
488 				prec = (*it).second;
489 				break;
490 			}
491 			level--;
492 		}
493 		return prec;
494 	}
495 
496 	// This records invariant varyings declared through
497 	// "invariant varying_name;".
addInvariantVarying(const std::string & originalName)498 	void addInvariantVarying(const std::string &originalName)
499 	{
500 		mInvariantVaryings.insert(originalName);
501 	}
502 	// If this returns false, the varying could still be invariant
503 	// if it is set as invariant during the varying variable
504 	// declaration - this piece of information is stored in the
505 	// variable's type, not here.
isVaryingInvariant(const std::string & originalName)506 	bool isVaryingInvariant(const std::string &originalName) const
507 	{
508 		return (mGlobalInvariant ||
509 			mInvariantVaryings.count(originalName) > 0);
510 	}
511 
setGlobalInvariant()512 	void setGlobalInvariant() { mGlobalInvariant = true; }
getGlobalInvariant()513 	bool getGlobalInvariant() const { return mGlobalInvariant; }
514 
hasUnmangledBuiltIn(const char * name)515 	bool hasUnmangledBuiltIn(const char *name) { return mUnmangledBuiltinNames.count(std::string(name)) > 0; }
516 
517 private:
518 	// Used to insert unmangled functions to check redeclaration of built-ins in ESSL 3.00.
insertUnmangledBuiltIn(const char * name)519 	void insertUnmangledBuiltIn(const char *name) { mUnmangledBuiltinNames.insert(std::string(name)); }
520 
521 protected:
currentLevel()522 	ESymbolLevel currentLevel() const { return static_cast<ESymbolLevel>(table.size() - 1); }
523 
524 	std::vector<TSymbolTableLevel*> table;
525 	typedef std::map< TBasicType, TPrecision > PrecisionStackLevel;
526 	std::vector< PrecisionStackLevel > precisionStack;
527 
528 	std::set<std::string> mUnmangledBuiltinNames;
529 
530 	std::set<std::string> mInvariantVaryings;
531 	bool mGlobalInvariant;
532 };
533 
534 #endif // _SYMBOL_TABLE_INCLUDED_
535