Store builtin symbols as const pointers

src/compiler/translator/Compiler.cpp

@@ -336,7 +336,8 @@ TIntermBlock *TCompiler::compileTreeImpl(const char *const shaderStrings[],
 
     // We preserve symbols at the built-in level from compile-to-compile.
     // Start pushing the user-defined symbols at global level.
-    TScopedSymbolTableLevel scopedSymbolLevel(&symbolTable);
+    TScopedSymbolTableLevel globalLevel(&symbolTable);
+    ASSERT(symbolTable.atGlobalLevel());
 
     // Parse shader.
     if (PaParseStrings(numStrings - firstSource, &shaderStrings[firstSource], nullptr,

src/compiler/translator/SymbolTable.cpp

@@ -13,12 +13,13 @@
 
 #include "compiler/translator/SymbolTable.h"
 
+#include <algorithm>
+#include <set>
+
 #include "angle_gl.h"
 #include "compiler/translator/ImmutableString.h"
 #include "compiler/translator/IntermNode.h"
-
-#include <stdio.h>
-#include <algorithm>
+#include "compiler/translator/StaticType.h"
 
 namespace sh
 {
@@ -44,9 +45,6 @@ class TSymbolTable::TSymbolTableLevel
 
     void setGlobalInvariant(bool invariant) { mGlobalInvariant = invariant; }
 
-    void insertUnmangledBuiltInName(const char *name);
-    bool hasUnmangledBuiltIn(const char *name) const;
-
   private:
     using tLevel        = TUnorderedMap<ImmutableString,
                                  TSymbol *,
@@ -55,8 +53,34 @@ class TSymbolTable::TSymbolTableLevel
     using tInsertResult = std::pair<tLevel::iterator, bool>;
 
     tLevel level;
+
     std::set<std::string> mInvariantVaryings;
     bool mGlobalInvariant;
+};
+
+class TSymbolTable::TSymbolTableBuiltInLevel
+{
+  public:
+    TSymbolTableBuiltInLevel() = default;
+
+    bool insert(const TSymbol *symbol);
+
+    // Insert a function using its unmangled name as the key.
+    bool insertUnmangled(const TFunction *function);
+
+    const TSymbol *find(const ImmutableString &name) const;
+
+    void insertUnmangledBuiltInName(const char *name);
+    bool hasUnmangledBuiltIn(const char *name) const;
+
+  private:
+    using tLevel        = TUnorderedMap<ImmutableString,
+                                 const TSymbol *,
+                                 ImmutableString::FowlerNollVoHash<sizeof(size_t)>>;
+    using tLevelPair    = const tLevel::value_type;
+    using tInsertResult = std::pair<tLevel::iterator, bool>;
+
+    tLevel mLevel;
 
     std::set<ImmutableString> mUnmangledBuiltInNames;
 };
@@ -65,7 +89,6 @@ bool TSymbolTable::TSymbolTableLevel::insert(TSymbol *symbol)
 {
     // returning true means symbol was added to the table
     tInsertResult result = level.insert(tLevelPair(symbol->getMangledName(), symbol));
-
     return result.second;
 }
 
@@ -73,7 +96,6 @@ bool TSymbolTable::TSymbolTableLevel::insertUnmangled(TFunction *function)
 {
     // returning true means symbol was added to the table
     tInsertResult result = level.insert(tLevelPair(function->name(), function));
-
     return result.second;
 }
 
@@ -81,34 +103,66 @@ TSymbol *TSymbolTable::TSymbolTableLevel::find(const ImmutableString &name) cons
 {
     tLevel::const_iterator it = level.find(name);
     if (it == level.end())
-        return 0;
+        return nullptr;
+    else
+        return (*it).second;
+}
+
+bool TSymbolTable::TSymbolTableBuiltInLevel::insert(const TSymbol *symbol)
+{
+    // returning true means symbol was added to the table
+    tInsertResult result = mLevel.insert(tLevelPair(symbol->getMangledName(), symbol));
+    return result.second;
+}
+
+bool TSymbolTable::TSymbolTableBuiltInLevel::insertUnmangled(const TFunction *function)
+{
+    // returning true means symbol was added to the table
+    tInsertResult result = mLevel.insert(tLevelPair(function->name(), function));
+    return result.second;
+}
+
+const TSymbol *TSymbolTable::TSymbolTableBuiltInLevel::find(const ImmutableString &name) const
+{
+    tLevel::const_iterator it = mLevel.find(name);
+    if (it == mLevel.end())
+        return nullptr;
     else
         return (*it).second;
 }
 
-void TSymbolTable::TSymbolTableLevel::insertUnmangledBuiltInName(const char *name)
+void TSymbolTable::TSymbolTableBuiltInLevel::insertUnmangledBuiltInName(const char *name)
 {
     mUnmangledBuiltInNames.insert(ImmutableString(name));
 }
 
-bool TSymbolTable::TSymbolTableLevel::hasUnmangledBuiltIn(const char *name) const
+bool TSymbolTable::TSymbolTableBuiltInLevel::hasUnmangledBuiltIn(const char *name) const
 {
     return mUnmangledBuiltInNames.count(ImmutableString(name)) > 0;
 }
 
+TSymbolTable::TSymbolTable() : mUniqueIdCounter(0), mUserDefinedUniqueIdsStart(-1)
+{
+}
+
+TSymbolTable::~TSymbolTable() = default;
+
+void TSymbolTable::pushBuiltInLevel()
+{
+    mBuiltInTable.push_back(
+        std::unique_ptr<TSymbolTableBuiltInLevel>(new TSymbolTableBuiltInLevel));
+}
+
 void TSymbolTable::push()
 {
-    table.push_back(new TSymbolTableLevel);
-    precisionStack.push_back(new PrecisionStackLevel);
+    mTable.push_back(std::unique_ptr<TSymbolTableLevel>(new TSymbolTableLevel));
+    mPrecisionStack.push_back(std::unique_ptr<PrecisionStackLevel>(new PrecisionStackLevel));
 }
 
 void TSymbolTable::pop()
 {
-    delete table.back();
-    table.pop_back();
-
-    delete precisionStack.back();
-    precisionStack.pop_back();
+    mTable.pop_back();
+    mPrecisionStack.pop_back();
 }
 
 const TFunction *TSymbolTable::markUserDefinedFunctionHasPrototypeDeclaration(
@@ -144,37 +198,31 @@ const TFunction *TSymbolTable::setUserDefinedFunctionParameterNamesFromDefinitio
 
 const TSymbol *TSymbolTable::find(const ImmutableString &name, int shaderVersion) const
 {
-    int level       = currentLevel();
-    TSymbol *symbol = nullptr;
-    do
+    int userDefinedLevel = static_cast<int>(mTable.size()) - 1;
+    while (userDefinedLevel >= 0)
     {
-        if (level == GLSL_BUILTINS)
-            level--;
-        if (level == ESSL3_1_BUILTINS && shaderVersion != 310)
-            level--;
-        if (level == ESSL3_BUILTINS && shaderVersion < 300)
-            level--;
-        if (level == ESSL1_BUILTINS && shaderVersion != 100)
-            level--;
-
-        symbol = table[level]->find(name);
-        level--;
-    } while (symbol == nullptr && level >= 0);
+        const TSymbol *symbol = mTable[userDefinedLevel]->find(name);
+        if (symbol)
+        {
+            return symbol;
+        }
+        userDefinedLevel--;
+    }
 
-    return symbol;
+    return findBuiltIn(name, shaderVersion, false);
 }
 
 TFunction *TSymbolTable::findUserDefinedFunction(const ImmutableString &name) const
 {
     // User-defined functions are always declared at the global level.
-    ASSERT(currentLevel() >= GLOBAL_LEVEL);
-    return static_cast<TFunction *>(table[GLOBAL_LEVEL]->find(name));
+    ASSERT(!mTable.empty());
+    return static_cast<TFunction *>(mTable[0]->find(name));
 }
 
 const TSymbol *TSymbolTable::findGlobal(const ImmutableString &name) const
 {
-    ASSERT(table.size() > GLOBAL_LEVEL);
-    return table[GLOBAL_LEVEL]->find(name);
+    ASSERT(!mTable.empty());
+    return mTable[0]->find(name);
 }
 
 const TSymbol *TSymbolTable::findBuiltIn(const ImmutableString &name, int shaderVersion) const
@@ -197,7 +245,7 @@ const TSymbol *TSymbolTable::findBuiltIn(const ImmutableString &name,
         if (level == ESSL1_BUILTINS && shaderVersion != 100)
             level--;
 
-        TSymbol *symbol = table[level]->find(name);
+        const TSymbol *symbol = mBuiltInTable[level]->find(name);
 
         if (symbol)
             return symbol;
@@ -206,12 +254,6 @@ const TSymbol *TSymbolTable::findBuiltIn(const ImmutableString &name,
     return nullptr;
 }
 
-TSymbolTable::~TSymbolTable()
-{
-    while (table.size() > 0)
-        pop();
-}
-
 constexpr bool IsGenType(const TType *type)
 {
     if (type)
@@ -314,9 +356,9 @@ void TSymbolTable::declareUserDefinedFunction(TFunction *function, bool insertUn
     if (insertUnmangledName)
     {
         // Insert the unmangled name to detect potential future redefinition as a variable.
-        table[GLOBAL_LEVEL]->insertUnmangled(function);
+        mTable[0]->insertUnmangled(function);
     }
-    table[GLOBAL_LEVEL]->insert(function);
+    mTable[0]->insert(function);
 }
 
 TVariable *TSymbolTable::insertVariable(ESymbolLevel level,
@@ -342,19 +384,17 @@ TVariable *TSymbolTable::insertVariable(ESymbolLevel level,
     return nullptr;
 }
 
-TVariable *TSymbolTable::insertVariableExt(ESymbolLevel level,
-                                           TExtension ext,
-                                           const ImmutableString &name,
-                                           const TType *type)
+void TSymbolTable::insertVariableExt(ESymbolLevel level,
+                                     TExtension ext,
+                                     const ImmutableString &name,
+                                     const TType *type)
 {
     ASSERT(level <= LAST_BUILTIN_LEVEL);
     ASSERT(type->isRealized());
     TVariable *var = new TVariable(this, name, type, SymbolType::BuiltIn, ext);
-    if (insert(level, var))
-    {
-        return var;
-    }
-    return nullptr;
+    bool inserted  = insert(level, var);
+    UNUSED_VARIABLE(inserted);
+    ASSERT(inserted);
 }
 
 bool TSymbolTable::insertVariable(ESymbolLevel level, TVariable *variable)
@@ -367,7 +407,14 @@ bool TSymbolTable::insertVariable(ESymbolLevel level, TVariable *variable)
 bool TSymbolTable::insert(ESymbolLevel level, TSymbol *symbol)
 {
     ASSERT(level > LAST_BUILTIN_LEVEL || mUserDefinedUniqueIdsStart == -1);
-    return table[level]->insert(symbol);
+    if (level <= LAST_BUILTIN_LEVEL)
+    {
+        return mBuiltInTable[level]->insert(symbol);
+    }
+    else
+    {
+        return mTable[level - LAST_BUILTIN_LEVEL - 1]->insert(symbol);
+    }
 }
 
 bool TSymbolTable::insertStructType(ESymbolLevel level, TStructure *str)
@@ -638,6 +685,13 @@ void TSymbolTable::insertBuiltInFunctionNoParametersExt(ESymbolLevel level,
            new TFunction(this, ImmutableString(name), rvalue, SymbolType::BuiltIn, false, op, ext));
 }
 
+void TSymbolTable::setDefaultPrecision(TBasicType type, TPrecision prec)
+{
+    int indexOfLastElement = static_cast<int>(mPrecisionStack.size()) - 1;
+    // Uses map operator [], overwrites the current value
+    (*mPrecisionStack[indexOfLastElement])[type] = prec;
+}
+
 TPrecision TSymbolTable::getDefaultPrecision(TBasicType type) const
 {
     if (!SupportsPrecision(type))
@@ -646,14 +700,14 @@ TPrecision TSymbolTable::getDefaultPrecision(TBasicType type) const
     // unsigned integers use the same precision as signed
     TBasicType baseType = (type == EbtUInt) ? EbtInt : type;
 
-    int level = static_cast<int>(precisionStack.size()) - 1;
-    assert(level >= 0);  // Just to be safe. Should not happen.
+    int level = static_cast<int>(mPrecisionStack.size()) - 1;
+    ASSERT(level >= 0);  // Just to be safe. Should not happen.
     // If we dont find anything we return this. Some types don't have predefined default precision.
     TPrecision prec = EbpUndefined;
     while (level >= 0)
     {
-        PrecisionStackLevel::iterator it = precisionStack[level]->find(baseType);
-        if (it != precisionStack[level]->end())
+        PrecisionStackLevel::iterator it = mPrecisionStack[level]->find(baseType);
+        if (it != mPrecisionStack[level]->end())
         {
             prec = (*it).second;
             break;
@@ -666,38 +720,36 @@ TPrecision TSymbolTable::getDefaultPrecision(TBasicType type) const
 void TSymbolTable::addInvariantVarying(const std::string &originalName)
 {
     ASSERT(atGlobalLevel());
-    table[currentLevel()]->addInvariantVarying(originalName);
+    mTable.back()->addInvariantVarying(originalName);
 }
 
 bool TSymbolTable::isVaryingInvariant(const std::string &originalName) const
 {
     ASSERT(atGlobalLevel());
-    return table[currentLevel()]->isVaryingInvariant(originalName);
+    return mTable.back()->isVaryingInvariant(originalName);
 }
 
 void TSymbolTable::setGlobalInvariant(bool invariant)
 {
     ASSERT(atGlobalLevel());
-    table[currentLevel()]->setGlobalInvariant(invariant);
+    mTable.back()->setGlobalInvariant(invariant);
 }
 
 void TSymbolTable::insertUnmangledBuiltInName(const char *name, ESymbolLevel level)
 {
-    ASSERT(level >= 0 && level < static_cast<ESymbolLevel>(table.size()));
+    ASSERT(level >= 0 && level <= LAST_BUILTIN_LEVEL);
     ASSERT(mUserDefinedUniqueIdsStart == -1);
-    table[level]->insertUnmangledBuiltInName(name);
+    mBuiltInTable[level]->insertUnmangledBuiltInName(name);
 }
 
 bool TSymbolTable::hasUnmangledBuiltInAtLevel(const char *name, ESymbolLevel level)
 {
-    ASSERT(level >= 0 && level < static_cast<ESymbolLevel>(table.size()));
-    return table[level]->hasUnmangledBuiltIn(name);
+    ASSERT(level >= 0 && level <= LAST_BUILTIN_LEVEL);
+    return mBuiltInTable[level]->hasUnmangledBuiltIn(name);
 }
 
 bool TSymbolTable::hasUnmangledBuiltInForShaderVersion(const char *name, int shaderVersion)
 {
-    ASSERT(static_cast<ESymbolLevel>(table.size()) > LAST_BUILTIN_LEVEL);
-
     for (int level = LAST_BUILTIN_LEVEL; level >= 0; --level)
     {
         if (level == ESSL3_1_BUILTINS && shaderVersion != 310)
@@ -713,7 +765,7 @@ bool TSymbolTable::hasUnmangledBuiltInForShaderVersion(const char *name, int sha
             --level;
         }
 
-        if (table[level]->hasUnmangledBuiltIn(name))
+        if (mBuiltInTable[level]->hasUnmangledBuiltIn(name))
         {
             return true;
         }
@@ -731,7 +783,7 @@ void TSymbolTable::clearCompilationResults()
     mUniqueIdCounter = mUserDefinedUniqueIdsStart;
 
     // User-defined scopes should have already been cleared when the compilation finished.
-    ASSERT(table.size() == LAST_BUILTIN_LEVEL + 1u);
+    ASSERT(mTable.size() == 0u);
 }
 
 int TSymbolTable::nextUniqueIdValue()
@@ -745,11 +797,14 @@ void TSymbolTable::initializeBuiltIns(sh::GLenum type,
                                       const ShBuiltInResources &resources)
 {
     ASSERT(isEmpty());
-    push();  // COMMON_BUILTINS
-    push();  // ESSL1_BUILTINS
-    push();  // ESSL3_BUILTINS
-    push();  // ESSL3_1_BUILTINS
-    push();  // GLSL_BUILTINS
+    pushBuiltInLevel();  // COMMON_BUILTINS
+    pushBuiltInLevel();  // ESSL1_BUILTINS
+    pushBuiltInLevel();  // ESSL3_BUILTINS
+    pushBuiltInLevel();  // ESSL3_1_BUILTINS
+    pushBuiltInLevel();  // GLSL_BUILTINS
+
+    // We need just one precision stack level for predefined precisions.
+    mPrecisionStack.push_back(std::unique_ptr<PrecisionStackLevel>(new PrecisionStackLevel));
 
     switch (type)
     {

src/compiler/translator/SymbolTable.h

@@ -31,15 +31,13 @@
 //
 
 #include <array>
-#include <assert.h>
-#include <set>
+#include <memory>
 
 #include "common/angleutils.h"
 #include "compiler/translator/ExtensionBehavior.h"
 #include "compiler/translator/ImmutableString.h"
 #include "compiler/translator/InfoSink.h"
 #include "compiler/translator/IntermNode.h"
-#include "compiler/translator/StaticType.h"
 #include "compiler/translator/Symbol.h"
 
 namespace sh
@@ -62,19 +60,17 @@ const int GLOBAL_LEVEL       = 5;
 class TSymbolTable : angle::NonCopyable
 {
   public:
-    TSymbolTable() : mUniqueIdCounter(0), mUserDefinedUniqueIdsStart(-1)
-    {
-        // The symbol table cannot be used until push() is called, but
-        // the lack of an initial call to push() can be used to detect
-        // that the symbol table has not been preloaded with built-ins.
-    }
+    TSymbolTable();
+    // To start using the symbol table after construction:
+    // * initializeBuiltIns() needs to be called.
+    // * push() needs to be called to push the global level.
 
     ~TSymbolTable();
 
     // When the symbol table is initialized with the built-ins, there should
     // 'push' calls, so that built-ins are at level 0 and the shader
     // globals are at level 1.
-    bool isEmpty() const { return table.empty(); }
+    bool isEmpty() const { return mTable.empty(); }
     bool atBuiltInLevel() const { return currentLevel() <= LAST_BUILTIN_LEVEL; }
     bool atGlobalLevel() const { return currentLevel() == GLOBAL_LEVEL; }
 
@@ -109,12 +105,7 @@ class TSymbolTable : angle::NonCopyable
                                int shaderVersion,
                                bool includeGLSLBuiltins) const;
 
-    void setDefaultPrecision(TBasicType type, TPrecision prec)
-    {
-        int indexOfLastElement = static_cast<int>(precisionStack.size()) - 1;
-        // Uses map operator [], overwrites the current value
-        (*precisionStack[indexOfLastElement])[type] = prec;
-    }
+    void setDefaultPrecision(TBasicType type, TPrecision prec);
 
     // Searches down the precisionStack for a precision qualifier
     // for the specified TBasicType
@@ -146,18 +137,24 @@ class TSymbolTable : angle::NonCopyable
     friend class TSymbolUniqueId;
     int nextUniqueIdValue();
 
+    class TSymbolTableBuiltInLevel;
     class TSymbolTableLevel;
 
-    ESymbolLevel currentLevel() const { return static_cast<ESymbolLevel>(table.size() - 1); }
+    void pushBuiltInLevel();
+
+    ESymbolLevel currentLevel() const
+    {
+        return static_cast<ESymbolLevel>(mTable.size() + LAST_BUILTIN_LEVEL);
+    }
 
     // The insert* entry points are used when initializing the symbol table with built-ins.
     // They return the created symbol / true in case the declaration was successful, and nullptr /
     // false if the declaration failed due to redefinition.
     TVariable *insertVariable(ESymbolLevel level, const ImmutableString &name, const TType *type);
-    TVariable *insertVariableExt(ESymbolLevel level,
-                                 TExtension ext,
-                                 const ImmutableString &name,
-                                 const TType *type);
+    void insertVariableExt(ESymbolLevel level,
+                           TExtension ext,
+                           const ImmutableString &name,
+                           const TType *type);
     bool insertVariable(ESymbolLevel level, TVariable *variable);
     bool insertStructType(ESymbolLevel level, TStructure *str);
     bool insertInterfaceBlock(ESymbolLevel level, TInterfaceBlock *interfaceBlock);
@@ -272,9 +269,13 @@ class TSymbolTable : angle::NonCopyable
                                     const ShBuiltInResources &resources);
     void markBuiltInInitializationFinished();
 
-    std::vector<TSymbolTableLevel *> table;
+    std::vector<std::unique_ptr<TSymbolTableBuiltInLevel>> mBuiltInTable;
+    std::vector<std::unique_ptr<TSymbolTableLevel>> mTable;
+
+    // There's one precision stack level for predefined precisions and then one level for each scope
+    // in table.
     typedef TMap<TBasicType, TPrecision> PrecisionStackLevel;
-    std::vector<PrecisionStackLevel *> precisionStack;
+    std::vector<std::unique_ptr<PrecisionStackLevel>> mPrecisionStack;
 
     int mUniqueIdCounter;