Document how to add a new feature enabled by an extension in Versions.cpp. Also reorganized slightly to localize related functions.

git-svn-id: https://cvs.khronos.org/svn/repos/ogl/trunk/ecosystem/public/sdk/tools/glslang@23376 e7fa87d3-cd2b-0410-9028-fcbf551c1848

README.txt

@@ -7,10 +7,13 @@ There are two components:
 2) A standalone wrapper, glslangValidator, that can be used as a shader 
    validation tool. 
 
+How to add a feature protected by a version/extension/stage/profile:  See the
+comment in glslang/MachineIndependent/Versions.cpp.
+
 Things left to do:  See Todo.txt
 
-Execution
+Execution of Standalone Wrapper
----------
+-------------------------------
 
 There are binaries in the Install/Windows and Install/Linux directories.
 
@@ -26,7 +29,10 @@ The applied stage-specific rules are based on the file extension:
     .frag for a fragment shader
     .comp for a compute shader
 
-Source: Build and run on linux
+There is also a non-shader extension
+    .conf for a configuration file of limits, see usage statement for example
+
+Source: Build and run on Linux
 -------------------------------
 
 A simple bash script "BuildLinux.sh" is provided at the root directory

Todo.txt

@@ -1,7 +1,5 @@
 Current functionality level: ESSL 3.0
 
-- extension adding process
-
 Link Validation
     + provide input config file for setting limits
 	  - also consider spitting out measures of complexity
@@ -166,22 +164,24 @@ Shader Functionality to Implement/Finish
       - Allow swizzle operations on scalars.
       - Positive signed decimal literals, as well as octal and hexadecimal, can set all 32 bits. This includes setting the sign bit to create a negative value.
       - Make GLSL consistent with the API regarding user clipping, by no longer referring to gl_Positionwhen gl_ClipVertex is not written. Rather, user clipping becomes undefined.
-      - Clarified that a comma sequence-operator expression cannot be a constant expression. E.g., “(2,3)” is not allowed, semantically, as a valid constant expression 3, even though it is an expression that will evaluate to 3.
+      - Clarified that a comma sequence-operator expression cannot be a constant expression. E.g., “(2,3)” is not allowed, semantically, 
+            as a valid constant expression 3, even though it is an expression that will evaluate to 3.
       - Use vec2 instead of vec3 for coordinate in textureGather*(sampler2DRect,...).
       - Clarify that textureGatherOffset() can take non-constants for the offsets.
     GLSL 4.3
-      - Add shader storage bufferobjects, as per the ARB_shader_storage_buffer_object extension. 
+      - Add shader storage buffer objects, as per the ARB_shader_storage_buffer_object extension. This includes 
-        This includes 1) allowing the last member of a storage buffer block to be an array that does not 
+            - allowing the last member of a storage buffer block to be an array that does not know its size until render time
-        know its size until render time, and 2) read/write memory shared with the application and other 
+            - read/write memory shared with the application and other shader invocations
-        shader invocations. It also adds the std430layout qualifier for shader storage blocks.
+            - adding the std430 layout qualifier for shader storage blocks
       - Allow .length() on all arrays; returning a compile-time constant or not, depending on how the 
         array is sized, as per the ARB_shader_storage_buffer_object extension.
       - Be clear that implicit array sizing is only within a stage, not cross stage.
-      - Array clarifications: 1) All arrays are inherently homogeneous, except for arrays of the new 
+      - Array clarifications: 
-        shader storage buffer objects. 2) Arrays of shader storage buffer objects will be dereferenced 
+            - All arrays are inherently homogeneous, except for arrays of the new shader storage buffer objects
-        when the .length() method is used on an unsized array member, so that must a have valid index. 
+            - Arrays of shader storage buffer objects will be dereferenced when the .length() method is used on an unsized array 
-        3) Arrays of other objects (uniform blocks) containing implicitly sized arrays will have the same 
+                member, so that must a have valid index. 
-        implicit size for all elements of the array.
+            - Arrays of other objects (uniform blocks) containing implicitly sized arrays will have the same implicit size for all 
+                elements of the array.
       - Arrays of arrays are now supported, as per the GL_ARB_arrays_of_arraysextension.
       - Compute shaders are now supported, as per the GL_ARB_compute_shader extension.
       - Added imageSize() built-ins to query the dimensions of an image.

glslang/MachineIndependent/Initialize.cpp

@@ -584,7 +584,7 @@ void TBuiltIns::initialize(int version, EProfile profile)
         s.append("\n");
 
         //
-        // Original-style texture Functions existing in both stages.
+        // Original-style texture functions existing in both stages.
         // (Per-stage functions below.)
         //
         if (profile == EEsProfile && version == 100 ||

glslang/MachineIndependent/Intermediate.cpp

@@ -1098,7 +1098,7 @@ void TIntermediate::checkCallGraphCycles(TInfoSink& infoSink)
 void TIntermediate::error(TInfoSink& infoSink, const char* message)
 {
     infoSink.info.prefix(EPrefixError);
-    infoSink.info << "Linking " << StageName[language] << " stage: " << message << "\n";
+    infoSink.info << "Linking " << StageName(language) << " stage: " << message << "\n";
 
     ++numErrors;
 }

glslang/MachineIndependent/ParseHelper.cpp

@@ -249,59 +249,6 @@ void TParseContext::handlePragma(const char **tokens, int numTokens)
     }
 }
 
-TBehavior TParseContext::getExtensionBehavior(const char* behavior)
-{
-    if (!strcmp("require", behavior))
-        return EBhRequire;
-    else if (!strcmp("enable", behavior))
-        return EBhEnable;
-    else if (!strcmp("disable", behavior))
-        return EBhDisable;
-    else if (!strcmp("warn", behavior))
-        return EBhWarn;
-    else {
-        error(currentLoc, "behavior not supported", "#extension", behavior);
-        return EBhDisable;
-    }
-}
-
-void TParseContext::updateExtensionBehavior(const char* extName, const char* behavior)
-{
-    TBehavior behaviorVal = getExtensionBehavior(behavior);
-    TMap<TString, TBehavior>:: iterator iter;
-    TString msg;
-
-    // special cased for all extension
-    if (!strcmp(extName, "all")) {
-        if (behaviorVal == EBhRequire || behaviorVal == EBhEnable) {
-            error(currentLoc, "extension 'all' cannot have 'require' or 'enable' behavior", "#extension", "");
-            return;
-        } else {
-            for (iter = extensionBehavior.begin(); iter != extensionBehavior.end(); ++iter)
-                iter->second = behaviorVal;
-        }
-    } else {
-        iter = extensionBehavior.find(TString(extName));
-        if (iter == extensionBehavior.end()) {
-            switch (behaviorVal) {
-            case EBhRequire:
-                error(currentLoc, "extension not supported", "#extension", extName);
-                break;
-            case EBhEnable:
-            case EBhWarn:
-            case EBhDisable:
-                warn(currentLoc, "extension not supported", "#extension", extName);
-                break;
-            default:
-                assert(0 && "unexpected behaviorVal");
-            }
-
-            return;
-        } else
-            iter->second = behaviorVal;
-    }
-}
-
 ///////////////////////////////////////////////////////////////////////
 //
 // Sub- vector and matrix fields
@@ -538,12 +485,11 @@ TIntermTyped* TParseContext::handleBracketDereference(TSourceLoc loc, TIntermTyp
             if (base->isArray() && base->getType().getArraySize() == 0)
                 error(loc, "", "[", "array must be redeclared with a size before being indexed with a variable");
             if (base->getBasicType() == EbtBlock)
-                requireProfile(base->getLoc(), static_cast<EProfileMask>(~EEsProfileMask), "variable indexing block array");
+                requireProfile(base->getLoc(), ~EEsProfile, "variable indexing block array");
             if (base->getBasicType() == EbtSampler && version >= 130) {
                 const char* explanation = "variable indexing sampler array";
-                requireProfile(base->getLoc(), static_cast<EProfileMask>(ECoreProfileMask | ECompatibilityProfileMask), explanation);
+                requireProfile(base->getLoc(), ECoreProfile | ECompatibilityProfile, explanation);
-                profileRequires(base->getLoc(), ECoreProfile, 400, 0, explanation);
+                profileRequires(base->getLoc(), ECoreProfile | ECompatibilityProfile, 400, 0, explanation);
-                profileRequires(base->getLoc(), ECompatibilityProfile, 400, 0, explanation);
             }
 
             result = intermediate.addIndex(EOpIndexIndirect, base, index, loc);
@@ -662,7 +608,7 @@ TFunction* TParseContext::handleFunctionDeclarator(TSourceLoc loc, TFunction& fu
 {
     // ES can't declare prototypes inside functions
     if (! symbolTable.atGlobalLevel())
-        requireProfile(loc, static_cast<EProfileMask>(~EEsProfileMask), "local function declaration");
+        requireProfile(loc, ~EEsProfile, "local function declaration");
 
     //
     // Multiple declarations of the same function are allowed.
@@ -1479,7 +1425,7 @@ void TParseContext::globalQualifierFix(TSourceLoc loc, TQualifier& qualifier, co
             return;
         }
         if (publicType.arraySizes) {
-            requireProfile(loc, (EProfileMask)~EEsProfileMask, "vertex input arrays");
+            requireProfile(loc, ~EEsProfile, "vertex input arrays");
             profileRequires(loc, ENoProfile, 150, 0, "vertex input arrays");
         }
     }
@@ -1706,7 +1652,7 @@ bool TParseContext::arrayQualifierError(TSourceLoc loc, const TQualifier& qualif
         profileRequires(loc, ENoProfile, 120, "GL_3DL_array_objects", "const array");
 
     if (qualifier.storage == EvqVaryingIn && language == EShLangVertex) {
-        requireProfile(loc, (EProfileMask)~EEsProfileMask, "vertex input arrays");
+        requireProfile(loc, ~EEsProfile, "vertex input arrays");
         profileRequires(loc, ENoProfile, 150, 0, "vertex input arrays");
     }
 
@@ -1726,9 +1672,8 @@ void TParseContext::arraySizeRequiredCheck(TSourceLoc loc, int size)
 
 void TParseContext::arrayDimError(TSourceLoc loc)
 {
-    requireProfile(loc, (EProfileMask)(ECoreProfileMask | ECompatibilityProfileMask), "arrays of arrays");
+    requireProfile(loc, ECoreProfile | ECompatibilityProfile, "arrays of arrays");
-    profileRequires(loc, ECoreProfile, 430, 0, "arrays of arrays");
+    profileRequires(loc, ECoreProfile | ECompatibilityProfile, 430, 0, "arrays of arrays");
-    profileRequires(loc, ECompatibilityProfile, 430, 0, "arrays of arrays");
 }
 
 void TParseContext::arrayDimCheck(TSourceLoc loc, TArraySizes* sizes1, TArraySizes* sizes2)
@@ -2387,7 +2332,7 @@ void TParseContext::addBlock(TSourceLoc loc, TTypeList& typeList, const TString*
         arraySizeRequiredCheck(loc, arraySizes->getSize());        
 
     if (currentBlockDefaults.storage == EvqUniform) {
-        requireProfile(loc, (EProfileMask)(~ENoProfileMask), "uniform block");
+        requireProfile(loc, ~ENoProfile, "uniform block");
         profileRequires(loc, EEsProfile, 300, 0, "uniform block");
     } else {
         error(loc, "only uniform interface blocks are supported", blockName->c_str(), "");
@@ -2788,17 +2733,4 @@ TIntermTyped* TParseContext::addConstStruct(TString& identifier, TIntermTyped* n
     return typedNode;
 }
 
-//
-// Initialize all supported extensions to disable
-//
-void TParseContext::initializeExtensionBehavior()
-{
-    //
-    // example code: extensionBehavior["test"] = EBhDisable; // where "test" is the name of 
-    // supported extension
-    //
-    extensionBehavior["GL_ARB_texture_rectangle"] = EBhDisable;
-    extensionBehavior["GL_3DL_array_objects"] = EBhDisable;
-}
-
 } // end namespace glslang

glslang/MachineIndependent/ParseHelper.h

@@ -43,13 +43,6 @@
 
 namespace glslang {
 
-typedef enum {
-    EBhRequire,
-    EBhEnable,
-    EBhWarn,
-    EBhDisable
-} TBehavior;
-
 struct TPragma {
 	TPragma(bool o, bool d) : optimize(o), debug(d) { }
 	bool optimize;
@@ -71,7 +64,6 @@ public:
 
 public:
     bool parseShaderStrings(TPpContext&, char* strings[], int strLen[], int numStrings);
-    void initializeExtensionBehavior();
     void parserError(const char *s);     // for bison's yyerror
 
     void C_DECL error(TSourceLoc, const char *szReason, const char *szToken,
@@ -148,15 +140,6 @@ public:
 
     bool arraySetMaxSize(TSourceLoc, TIntermSymbol*, int);
 
-    void requireProfile(TSourceLoc, EProfileMask profileMask, const char *featureDesc);
-    void requireStage(TSourceLoc, EShLanguageMask languageMask, const char *featureDesc);
-    void profileRequires(TSourceLoc, EProfile callingProfile, int minVersion, int numExtensions, const char* extensions[], const char *featureDesc);
-    void profileRequires(TSourceLoc, EProfile callingProfile, int minVersion, const char* extension, const char *featureDesc);
-    void checkDeprecated(TSourceLoc, EProfile callingProfile, int depVersion, const char *featureDesc);
-    void requireNotRemoved(TSourceLoc, EProfile callingProfile, int removedVersion, const char *featureDesc);
-    void fullIntegerCheck(TSourceLoc, const char* op);
-    void doubleCheck(TSourceLoc, const char* op);
-
     void setScanContext(TScanContext* c) { scanContext = c; }
     TScanContext* getScanContext() const { return scanContext; }
     void setPpContext(TPpContext* c) { ppContext = c; }
@@ -164,9 +147,21 @@ public:
     void addError() { ++numErrors; }
     int getNumErrors() const { return numErrors; }
 
+    // The following are implemented in Versions.cpp to localize version/profile/stage/extensions control
+    void initializeExtensionBehavior();
+    void requireProfile(TSourceLoc, int queryProfiles, const char *featureDesc);
+    void profileRequires(TSourceLoc, int queryProfiles, int minVersion, int numExtensions, const char* extensions[], const char *featureDesc);
+    void profileRequires(TSourceLoc, int queryProfiles, int minVersion, const char* extension, const char *featureDesc);
+    void requireStage(TSourceLoc, EShLanguageMask, const char *featureDesc);
+    void requireStage(TSourceLoc, EShLanguage, const char *featureDesc);
+    void checkDeprecated(TSourceLoc, int queryProfiles, int depVersion, const char *featureDesc);
+    void requireNotRemoved(TSourceLoc, int queryProfiles, int removedVersion, const char *featureDesc);
+    void fullIntegerCheck(TSourceLoc, const char* op);
+    void doubleCheck(TSourceLoc, const char* op);
+
 protected:
     const char* getPreamble();
-    TBehavior getExtensionBehavior(const char* behavior);
+    TExtensionBehavior getExtensionBehavior(const char* behavior);
     void nonInitConstCheck(TSourceLoc, TString& identifier, TType& type);
     TVariable* declareNonArray(TSourceLoc, TString& identifier, TType&, bool& newDeclaration);
     void declareArray(TSourceLoc, TString& identifier, const TType&, TVariable*&, bool& newDeclaration);
@@ -208,7 +203,7 @@ protected:
     TPpContext* ppContext;
     int numErrors;               // number of compile-time errors encountered
     bool parsingBuiltins;        // true if parsing built-in symbols/functions
-    TMap<TString, TBehavior> extensionBehavior;    // for each extension string, what it's current enablement is
+    TMap<TString, TExtensionBehavior> extensionBehavior;    // for each extension string, what it's current behavior is set to
     static const int maxSamplerIndex = EsdNumDims * (EbtNumTypes * (2 * 2)); // see computeSamplerTypeIndex()
     TPrecisionQualifier defaultSamplerPrecision[maxSamplerIndex];
     bool afterEOF;

glslang/MachineIndependent/ShaderLang.cpp

@@ -59,9 +59,11 @@ namespace { // anonymous namespace for file-local functions and symbols
 
 using namespace glslang;
 
+// Local mapping functions for making arrays of symbol tables....
+
 int MapVersionToIndex(int version)
 {
-        switch(version) {
+        switch (version) {
         case 100: return  0;
         case 110: return  1;
         case 120: return  2;
@@ -81,6 +83,19 @@ int MapVersionToIndex(int version)
 }                      // V
 const int VersionCount = 13;  // number of case statements above
 
+int MapProfileToIndex(EProfile profile)
+{
+    switch (profile) {
+    case ENoProfile:             return 0;
+    case ECoreProfile:           return 1;
+    case ECompatibilityProfile:  return 2;
+    case EEsProfile:             return 3;
+    default:                         // |
+        return 0;                    // |
+    }                                // |
+}                                    // V
+const int ProfileCount                = 4;   // number of case statements above
+
 // only one of these needed for non-ES; ES needs 2 for different precision defaults of built-ins
 enum EPrecisionClass {
     EPcGeneral,
@@ -96,8 +111,8 @@ enum EPrecisionClass {
 // Each has a different set of built-ins, and we want to preserve that from
 // compile to compile.
 //
-TSymbolTable* CommonSymbolTable[VersionCount][EProfileCount][EPcCount] = {};
+TSymbolTable* CommonSymbolTable[VersionCount][ProfileCount][EPcCount] = {};
-TSymbolTable* SharedSymbolTables[VersionCount][EProfileCount][EShLangCount] = {};
+TSymbolTable* SharedSymbolTables[VersionCount][ProfileCount][EShLangCount] = {};
 
 TPoolAllocator* PerProcessGPA = 0;
 
@@ -216,7 +231,8 @@ void SetupBuiltinSymbolTable(int version, EProfile profile)
 
     // See if it's already been done for this version/profile combination
     int versionIndex = MapVersionToIndex(version);
-    if (CommonSymbolTable[versionIndex][profile][EPcGeneral]) {
+    int profileIndex = MapProfileToIndex(profile);
+    if (CommonSymbolTable[versionIndex][profileIndex][EPcGeneral]) {
         glslang::ReleaseGlobalLock();
 
         return;
@@ -244,17 +260,17 @@ void SetupBuiltinSymbolTable(int version, EProfile profile)
     // Copy the local symbol tables from the new pool to the global tables using the process-global pool
     for (int precClass = 0; precClass < EPcCount; ++precClass) {
         if (! commonTable[precClass]->isEmpty()) {
-            CommonSymbolTable[versionIndex][profile][precClass] = new TSymbolTable;
+            CommonSymbolTable[versionIndex][profileIndex][precClass] = new TSymbolTable;
-            CommonSymbolTable[versionIndex][profile][precClass]->copyTable(*commonTable[precClass]);
+            CommonSymbolTable[versionIndex][profileIndex][precClass]->copyTable(*commonTable[precClass]);
-            CommonSymbolTable[versionIndex][profile][precClass]->readOnly();
+            CommonSymbolTable[versionIndex][profileIndex][precClass]->readOnly();
         }
     }
     for (int stage = 0; stage < EShLangCount; ++stage) {
         if (! stageTables[stage]->isEmpty()) {
-            SharedSymbolTables[versionIndex][profile][stage] = new TSymbolTable;
+            SharedSymbolTables[versionIndex][profileIndex][stage] = new TSymbolTable;
-            SharedSymbolTables[versionIndex][profile][stage]->adoptLevels(*CommonSymbolTable[versionIndex][profile][CommonIndex(profile, (EShLanguage)stage)]);
+            SharedSymbolTables[versionIndex][profileIndex][stage]->adoptLevels(*CommonSymbolTable[versionIndex][profileIndex][CommonIndex(profile, (EShLanguage)stage)]);
-            SharedSymbolTables[versionIndex][profile][stage]->copyTable(*stageTables[stage]);
+            SharedSymbolTables[versionIndex][profileIndex][stage]->copyTable(*stageTables[stage]);
-            SharedSymbolTables[versionIndex][profile][stage]->readOnly();
+            SharedSymbolTables[versionIndex][profileIndex][stage]->readOnly();
         }    
     }
 
@@ -433,7 +449,7 @@ bool CompileDeferred(
     SetupBuiltinSymbolTable(version, profile);
     
     TSymbolTable* cachedTable = SharedSymbolTables[MapVersionToIndex(version)]
-                                                  [profile]
+                                                  [MapProfileToIndex(profile)]
                                                   [compiler->getLanguage()];
     
     // Dynamically allocate the symbol table so we can control when it is deallocated WRT the pool.
@@ -569,7 +585,7 @@ void ShDestruct(ShHandle handle)
 int __fastcall ShFinalize()
 {
     for (int version = 0; version < VersionCount; ++version)
-        for (int p = 0; p < EProfileCount; ++p)
+        for (int p = 0; p < ProfileCount; ++p)
             for (int lang = 0; lang < EShLangCount; ++lang)
                 delete SharedSymbolTables[version][p][lang];
 
@@ -964,7 +980,7 @@ bool TProgram::linkStage(EShLanguage stage, EShMessages messages)
         merged = intermediate[stage];
     }
 
-    infoSink->info << "\nLinked " << StageName[stage] << " stage:\n\n";
+    infoSink->info << "\nLinked " << StageName(stage) << " stage:\n\n";
 
     if (stages[stage].size() > 1) {
         std::list<TShader*>::const_iterator it;

glslang/MachineIndependent/Versions.cpp

@@ -37,68 +37,166 @@
 //
 // Help manage multiple profiles, versions, extensions etc.
 //
-// These don't return error codes, as the presumption is parsing
+// These don't return error codes, as the presumption is parsing will 
-// will always continue as if the feature were present, and there
+// always continue as if the tested feature were enabled, and thus there
-// is no error recovery needed to enable that.
+// is no error recovery needed.
+//
+
+//
+// HOW TO add a feature enabled by an extension.
+//
+// To add a new hypothetical "Feature F" to the front end, where an extension
+// "XXX_extension_X" can be used to enable the feature, do the following.
+// 
+// 1) Understand that specific features are what are error-checked for, not
+//    extensions:  A specific Feature F might be enabled by an extension, or a 
+//    particular version in a particular profile, or a stage, or combinations, etc.
+//    
+//    The basic mechanism is to use the following to "declare" all the things that 
+//    enable/disable Feature F, in a code path that implements Feature F:
+//    
+//        requireProfile()
+//        profileRequires()
+//        requireStage()
+//        checkDeprecated()
+//        requireNotRemoved()
+//    
+//    Typically, only the first two calls are needed.  They go into a code path that 
+//    implements Feature F, and will log the proper error/warning messages.  Parsing 
+//    will then always continue as if the tested feature was enabled.
+//    
+//    There is typically no if-testing or conditional parsing, just insertion of requirements.
+// 
+// 2) Add extension initialization to TParseContext::initializeExtensionBehavior(),
+//    the first function below:
+// 
+//     extensionBehavior["XXX_extension_X"] = EBhDisable;
+// 
+// 3) Insert a profile check in the feature's path (unless all profiles support the feature,
+//    for some version level).  That is, call requireProfile() to constrain the profiles, e.g.:
+// 
+//         // ... in a path specific to Feature F...
+//         requireProfile(loc,
+//                        ECoreProfile | ECompatibilityProfile,
+//                        "Feature F");
+// 
+// 4) For each profile that supports the feature, insert version/extension checks:
+// 
+//    The mostly likely scenario is that Feature F can only be used with a
+//    particular profile if XXX_extension_X is present or the version is
+//    high enough that the core specification already incorporated it.
+// 
+//        // following the requireProfile() call...
+//        profileRequires(loc, 
+//                        ECoreProfile | ECompatibilityProfile,
+//                        420, // 0 if no version incorporated the feature into the core spec.
+//                        "XXX_extension_X", // can be a list of extensions that all add the feature
+//                        "Feature F");
+// 
+//    This allows the feature if either A) one of the extensions is enabled or
+//    B) the version is high enough.  If no version yet incorporates the feature
+//    into core, pass in 0.
+// 
+//    This can be called multiple times, if different profiles support the
+//    feature starting at different version numbers or with different 
+//    extensions.
+// 
+//    This must be called for each profile allowed by the initial call to requireProfile().
+// 
+//    Profiles are all masks, which can be "or"-ed together.
+// 
+//        ENoProfile
+//        ECoreProfile
+//        ECompatibilityProfile
+//        EEsProfile
+// 
+//    The ENoProfile profile is only for desktop, before profiles showed up in version 150;
+//    All other #version with no profile default to either es or core, and so have profiles.
+// 
+//    You can select all but a particular profile using ~.  The following basically means "desktop":
+// 
+//        ~EEsProfile
 //
 
 #include "ParseHelper.h"
 
 namespace glslang {
 
-const char* StageName[EShLangCount] = {
-    "vertex",
-    "tessellation control",
-    "tessellation evaluation",
-    "geometry",
-    "fragment",
-    "compute"
-};
-
-const char* ProfileName[EProfileCount] = {
-    "none",
-    "core",
-    "compatibility",
-    "es"
-};
-
 //
-// If only some profiles support a feature, use requireProfile() to specify
+// Initialize all extensions, almost always to 'disable', as once their features
-// which subset allows the feature.  If the current profile is not present,
+// are incorporated into a core version, their features are supported through allowing that
-// give an error message.
+// core version, not through a pseudo-enablement of the extension.
 //
-void TParseContext::requireProfile(TSourceLoc loc, EProfileMask profileMask, const char *featureDesc)
+void TParseContext::initializeExtensionBehavior()
 {
-    if (((1 << profile) & profileMask) == 0)
+    extensionBehavior["GL_ARB_texture_rectangle"] = EBhDisable;
-        error(loc, "not supported with this profile:", featureDesc, ProfileName[profile]);
+    extensionBehavior["GL_3DL_array_objects"] = EBhDisable;
+}
+
+const char* ProfileName(EProfile profile)
+{
+    switch (profile) {
+    case ENoProfile:             return "none";        
+    case ECoreProfile:           return "core";
+    case ECompatibilityProfile:  return "compatibility";
+    case EEsProfile:             return "es";
+    default:                     return "unknown profile";
+    }
 }
 
 //
-// If only some stages support a feature, use requireStage() to specify
+// When to use requireProfile():
-// which subset allows the feature.  If the current stage is not present,
+//
+//     If only some profiles support a feature.  However, if within a profile the feature 
+//     is version or extension specific, follow this call with calls to profileRequires().
+//
+// Operation:  If the current profile is not one of the profileMask,
 // give an error message.
 //
-void TParseContext::requireStage(TSourceLoc loc, EShLanguageMask languageMask, const char *featureDesc)
+void TParseContext::requireProfile(TSourceLoc loc, int profileMask, const char *featureDesc)
 {
-    if (((1 << language) & languageMask) == 0)
+    if (! (profile & profileMask))
-        error(loc, "not supported in this stage:", featureDesc, StageName[language]);
+        error(loc, "not supported with this profile:", featureDesc, ProfileName(profile));
+}
+
+const char* StageName(EShLanguage stage) 
+{
+    switch(stage) {
+    case EShLangVertex:         return "vertex";
+    case EShLangTessControl:    return "tessellation control";
+    case EShLangTessEvaluation: return "tessellation evaluation";
+    case EShLangGeometry:       return "geometry";
+    case EShLangFragment:       return "fragment";
+    case EShLangCompute:        return "compute";
+    default:                    return "unknown stage";
+    }
 }
 
 //
-// Within a profile, if a feature requires a version level or extension, use
+// When to use profileRequires():
-// ProfileRequires().  This only checks if the current profile matches
+//
-// the passed-in profile.
+//     If a set of profiles have the same requirements for what version or extensions
+//     are needed to support a feature.
+//
+//     It must be called for each profile that needs protection.  Use requireProfile() first
+//     to reduce that set of profiles.
+//
+// Operation: Will issue warnings/errors based on the current profile, version, and extension
+// behaviors.  It only checks extensions when the current profile is one of the profileMask.
+//
+// A minVersion of 0 means no version of the profileMask support this in core, 
+// the extension must be present.
 //
 
-// one that takes multiple extensions
+// entry point that takes multiple extensions
-void TParseContext::profileRequires(TSourceLoc loc, EProfile callingProfile, int minVersion, int numExtensions, const char* extensions[], const char *featureDesc)
+void TParseContext::profileRequires(TSourceLoc loc, int profileMask, int minVersion, int numExtensions, const char* extensions[], const char *featureDesc)
 {
-    if (profile == callingProfile) {
+    if (profile & profileMask) {
         bool okay = false;
-        if (version >= minVersion)
+        if (minVersion > 0 && version >= minVersion)
             okay = true;
         for (int i = 0; i < numExtensions; ++i) {
-            TBehavior behavior = extensionBehavior[extensions[i]];
+            TExtensionBehavior behavior = extensionBehavior[extensions[i]];
             switch (behavior) {
             case EBhWarn:
                 infoSink.info.message(EPrefixWarning, ("extension " + TString(extensions[i]) + " is being used for " + featureDesc).c_str(), loc);
@@ -116,19 +214,39 @@ void TParseContext::profileRequires(TSourceLoc loc, EProfile callingProfile, int
     }
 }
 
-// one that takes a single extension
+// entry point for the above that takes a single extension
-void TParseContext::profileRequires(TSourceLoc loc, EProfile callingProfile, int minVersion, const char* extension, const char *featureDesc)
+void TParseContext::profileRequires(TSourceLoc loc, int profileMask, int minVersion, const char* extension, const char *featureDesc)
 {
-    profileRequires(loc, callingProfile, minVersion, extension ? 1 : 0, &extension, featureDesc);
+    profileRequires(loc, profileMask, minVersion, extension ? 1 : 0, &extension, featureDesc);
 }
 
 //
-// Within a profile, see if a feature is deprecated and error or warn based on whether
+// When to use requireStage()
+//
+//     If only some stages support a feature.  
+//
+// Operation: If the current stage is not present, give an error message.
+//
+void TParseContext::requireStage(TSourceLoc loc, EShLanguageMask languageMask, const char *featureDesc)
+{
+    if (((1 << language) & languageMask) == 0)
+        error(loc, "not supported in this stage:", featureDesc, StageName(language));
+}
+
+// If only one stage supports a feature, this can be called.  But, all supporting stages
+// must be specified with one call.
+void TParseContext::requireStage(TSourceLoc loc, EShLanguage stage, const char *featureDesc)
+{
+    requireStage(loc, static_cast<EShLanguageMask>(1 << stage), featureDesc);
+}
+
+//
+// Within a set of profiles, see if a feature is deprecated and give an error or warning based on whether
 // a future compatibility context is being use.
 //
-void TParseContext::checkDeprecated(TSourceLoc loc, EProfile callingProfile, int depVersion, const char *featureDesc)
+void TParseContext::checkDeprecated(TSourceLoc loc, int profileMask, int depVersion, const char *featureDesc)
 {
-    if (profile == callingProfile) {
+    if (profile & profileMask) {
         if (version >= depVersion) {
             if (forwardCompatible)
                 error(loc, "deprecated, may be removed in future release", featureDesc, "");
@@ -140,30 +258,92 @@ void TParseContext::checkDeprecated(TSourceLoc loc, EProfile callingProfile, int
 }
 
 //
-// Within a profile, see if a feature has now been removed and if so, give an error.
+// Within a set of profiles, see if a feature has now been removed and if so, give an error.
 // The version argument is the first version no longer having the feature.
 //
-void TParseContext::requireNotRemoved(TSourceLoc loc, EProfile callingProfile, int removedVersion, const char *featureDesc)
+void TParseContext::requireNotRemoved(TSourceLoc loc, int profileMask, int removedVersion, const char *featureDesc)
 {
-    if (profile == callingProfile) {
+    if (profile & profileMask) {
         if (version >= removedVersion) {
             const int maxSize = 60;
             char buf[maxSize];
-            snprintf(buf, maxSize, "%s profile; removed in version %d", ProfileName[profile], removedVersion);
+            snprintf(buf, maxSize, "%s profile; removed in version %d", ProfileName(profile), removedVersion);
             error(loc, "no longer supported in", featureDesc, buf);
         }
     }
 }
 
+//
+// Translate from text string of extension's behavior to enum.
+//
+TExtensionBehavior TParseContext::getExtensionBehavior(const char* behavior)
+{
+    if (! strcmp("require", behavior))
+        return EBhRequire;
+    else if (! strcmp("enable", behavior))
+        return EBhEnable;
+    else if (! strcmp("disable", behavior))
+        return EBhDisable;
+    else if (! strcmp("warn", behavior))
+        return EBhWarn;
+    else {
+        error(currentLoc, "behavior not supported", "#extension", behavior);
+        return EBhDisable;
+    }
+}
+
+void TParseContext::updateExtensionBehavior(const char* extName, const char* behaviorString)
+{
+    TExtensionBehavior behavior = getExtensionBehavior(behaviorString);
+    TMap<TString, TExtensionBehavior>:: iterator iter;
+    TString msg;
+
+    // special case for the 'all' extension
+    if (! strcmp(extName, "all")) {
+        if (behavior == EBhRequire || behavior == EBhEnable) {
+            error(currentLoc, "extension 'all' cannot have 'require' or 'enable' behavior", "#extension", "");
+            return;
+        } else {
+            for (iter = extensionBehavior.begin(); iter != extensionBehavior.end(); ++iter)
+                iter->second = behavior;
+        }
+    } else {
+        iter = extensionBehavior.find(TString(extName));
+        if (iter == extensionBehavior.end()) {
+            switch (behavior) {
+            case EBhRequire:
+                error(currentLoc, "extension not supported", "#extension", extName);
+                break;
+            case EBhEnable:
+            case EBhWarn:
+            case EBhDisable:
+                warn(currentLoc, "extension not supported", "#extension", extName);
+                break;
+            default:
+                assert(0 && "unexpected behavior");
+            }
+
+            return;
+        } else
+            iter->second = behavior;
+    }
+}
+
+//
+// Call for any operation needing full GLSL integer data-type support.
+//
 void TParseContext::fullIntegerCheck(TSourceLoc loc, const char* op)
-{   
+{
     profileRequires(loc, ENoProfile, 130, 0, op); 
     profileRequires(loc, EEsProfile, 300, 0, op);
 }
 
+//
+// Call for any operation needing GLSL double data-type support.
+//
 void TParseContext::doubleCheck(TSourceLoc loc, const char* op)
-{   
+{
-    requireProfile(loc, (EProfileMask)(ECoreProfileMask | ECompatibilityProfileMask), op);
+    requireProfile(loc, ECoreProfile | ECompatibilityProfile, op);
     profileRequires(loc, ECoreProfile, 400, 0, op);
     profileRequires(loc, ECompatibilityProfile, 400, 0, op);
 }

glslang/MachineIndependent/Versions.h

@@ -40,19 +40,29 @@
 // Help manage multiple profiles, versions, extensions etc.
 //
 
+//
+// The behaviors from "#extension extension_name : behavior"
+//
 typedef enum {
-    ENoProfile,              // only for desktop, before profiles showed up
+    EBhRequire,
-    ECoreProfile,
+    EBhEnable,
-    ECompatibilityProfile,
+    EBhWarn,
-    EEsProfile,
+    EBhDisable
-    EProfileCount,
+} TExtensionBehavior;
+
+//
+// Profiles are set up for masking operations, so queries can be done on multiple
+// profiles at the same time.
+//
+// Don't maintain an ordinal set of enums (0,1,2,3...) to avoid all possible
+// defects from mixing the two different forms.
+//
+typedef enum {
+    EBadProfile           = 0,
+    ENoProfile            = (1 << 0), // only for desktop, before profiles showed up
+    ECoreProfile          = (1 << 1),
+    ECompatibilityProfile = (1 << 2),
+    EEsProfile            = (1 << 3)
 } EProfile;
 
-typedef enum {
-    ENoProfileMask            = (1 << ENoProfile),
-    ECoreProfileMask          = (1 << ECoreProfile),
-    ECompatibilityProfileMask = (1 << ECompatibilityProfile),
-    EEsProfileMask            = (1 << EEsProfile)
-} EProfileMask;
-
 #endif // _VERSIONS_INCLUDED_

glslang/MachineIndependent/glslang.y

@@ -1047,7 +1047,7 @@ interpolation_qualifier
     }
     | NOPERSPECTIVE {
         parseContext.globalCheck($1.loc, parseContext.symbolTable.atGlobalLevel(), "noperspective");
-        parseContext.requireProfile($1.loc, static_cast<EProfileMask>(~EEsProfileMask), "noperspective");
+        parseContext.requireProfile($1.loc, ~EEsProfile, "noperspective");
         parseContext.profileRequires($1.loc, ENoProfile, 130, 0, "noperspective");
         $$.init($1.loc);
         $$.qualifier.nopersp = true;
@@ -1138,7 +1138,7 @@ storage_qualifier
         $$.qualifier.storage = EvqConst;
     }
     | ATTRIBUTE {
-        parseContext.requireStage($1.loc, EShLangVertexMask, "attribute");
+        parseContext.requireStage($1.loc, EShLangVertex, "attribute");
         parseContext.checkDeprecated($1.loc, ECoreProfile, 130, "attribute");
         parseContext.checkDeprecated($1.loc, ENoProfile, 130, "attribute");
         parseContext.requireNotRemoved($1.loc, ECoreProfile, 420, "attribute");
@@ -1206,9 +1206,9 @@ storage_qualifier
         $$.qualifier.storage = EvqUniform; // TODO: 4.0 functionality: implement BUFFER
     }
     | SHARED {
-        parseContext.requireProfile($1.loc, static_cast<EProfileMask>(~EEsProfileMask), "shared");
+        parseContext.requireProfile($1.loc, ~EEsProfile, "shared");
         parseContext.profileRequires($1.loc, ECoreProfile, 430, 0, "shared");
-        parseContext.requireStage($1.loc, EShLangComputeMask, "shared");
+        parseContext.requireStage($1.loc, EShLangCompute, "shared");
         $$.init($1.loc);
         $$.qualifier.shared = true;
     }
@@ -2315,7 +2315,7 @@ jump_statement
             parseContext.error($1.loc, "function return is not matching type:", "return", "");
     }
     | DISCARD SEMICOLON {
-        parseContext.requireStage($1.loc, EShLangFragmentMask, "discard");
+        parseContext.requireStage($1.loc, EShLangFragment, "discard");
         $$ = parseContext.intermediate.addBranch(EOpKill, $1.loc);
     }
     ;

glslang/MachineIndependent/preprocessor/Pp.cpp

@@ -529,7 +529,7 @@ int TPpContext::CPPifdef(int defined, TPpToken * yylvalpp)
     int token = currentInput->scan(this, currentInput, yylvalpp);
     int name = yylvalpp->atom;
     if (++ifdepth > maxIfNesting) {
-        parseContext.error(yylvalpp->loc, "maximum nesting depth exceededextension name not specified", "#ifdef", "");
+        parseContext.error(yylvalpp->loc, "maximum nesting depth exceeded", "#ifdef", "");
         return 0;
     }
     elsetracker++;

glslang/Public/ShaderLang.h

@@ -96,7 +96,7 @@ typedef enum {
 
 namespace glslang {
 
-extern const char* StageName[EShLangCount];
+const char* StageName(EShLanguage);
 
 } // end namespace glslang