Correct textureGather*() extension support:

- add extension behavior and warning message for partial extension support
 - add partial support for gpu_shader5 for textureGather*
 - add interactions between texture rectangle and textureGather*
 - add checks to distinguish between gpu_shader5 and texture_gather extension feature differences


git-svn-id: https://cvs.khronos.org/svn/repos/ogl/trunk/ecosystem/public/sdk/tools/glslang@24183 e7fa87d3-cd2b-0410-9028-fcbf551c1848

glslang/MachineIndependent/Initialize.cpp

@@ -1498,8 +1498,6 @@ void TBuiltIns::add2ndGenerationSamplingImaging(int version, EProfile profile)
 
                         if ((dim == Esd1D || dim == EsdRect) && profile == EEsProfile)
                             continue;
-                        if (dim == EsdRect && version < 140)
-                            continue;
                         if (dim != Esd2D && ms)
                             continue;
                         if ((dim == Esd3D || dim == EsdRect) && arrayed)
@@ -1518,6 +1516,9 @@ void TBuiltIns::add2ndGenerationSamplingImaging(int version, EProfile profile)
                             if (shadow && bType > 0)
                                 continue;
 
+                            if (dim == EsdRect && version < 140 && bType > 0)
+                                continue;
+
                             //
                             // Now, make all the function prototypes for the type we just built...
                             //
@@ -1800,6 +1801,9 @@ void TBuiltIns::addGatherFunctions(TSampler sampler, TString& typeName, int vers
     if (sampler.ms)
         return;
 
+    if (version < 140 && sampler.dim == EsdRect && sampler.type != EbtFloat)
+        return;
+
     // make one string per stage to contain all functions of the passed-in type for that stage
     TString functions[EShLangCount];
 

glslang/MachineIndependent/ParseHelper.cpp

@@ -982,18 +982,45 @@ void TParseContext::nonOpBuiltInCheck(TSourceLoc loc, const TFunction& fnCandida
 
     if (fnCandidate.getName().compare(0, 7, "texture") == 0) {
         if (fnCandidate.getName().compare(0, 13, "textureGather") == 0) {
-            const char* feature = "texture gather function";
+            TString featureString = fnCandidate.getName() + "(...)";
+            const char* feature = featureString.c_str();
             requireProfile(loc, ~EEsProfile, feature);
-            profileRequires(loc, ~EEsProfile, 400, GL_ARB_texture_gather, feature); // TODO: GL_ARB_gpu_shader5
-            int lastArgIndex = fnCandidate.getParamCount() - 1;
-            if (fnCandidate[lastArgIndex].type->getBasicType() == EbtInt && fnCandidate[lastArgIndex].type->isScalar()) {
-                // the last integral argument to a texture gather must be a constant int between 0 and 3
-                if (callNode.getSequence()[lastArgIndex]->getAsConstantUnion()) {
-                    int value = callNode.getSequence()[lastArgIndex]->getAsConstantUnion()->getConstArray()[0].getIConst();
-                    if (value < 0 || value > 3)
-                        error(loc, "must be 0, 1, 2, or 3", "texture gather component", "");
+
+            int compArg = -1;  // track which argument, if any, is the constant component argument
+            if (fnCandidate.getName().compare("textureGatherOffset") == 0) {
+                // GL_ARB_texture_gather is good enough for 2D non-shadow textures with no component argument
+                if (fnCandidate[0].type->getSampler().dim == Esd2D && ! fnCandidate[0].type->getSampler().shadow && fnCandidate.getParamCount() == 3)
+                    profileRequires(loc, ~EEsProfile, 400, GL_ARB_texture_gather, feature);
+                else
+                    profileRequires(loc, ~EEsProfile, 400, GL_ARB_gpu_shader5, feature);
+                if (! fnCandidate[0].type->getSampler().shadow)
+                    compArg = 3;
+            } else if (fnCandidate.getName().compare("textureGatherOffsets") == 0) {
+                profileRequires(loc, ~EEsProfile, 400, GL_ARB_gpu_shader5, feature);
+                if (! fnCandidate[0].type->getSampler().shadow)
+                    compArg = 3;
+                // check for constant offsets
+                int offsetArg = fnCandidate[0].type->getSampler().shadow ? 3 : 2;
+                if (! callNode.getSequence()[offsetArg]->getAsConstantUnion())
+                    error(loc, "must be a compile-time constant:", feature, "offsets argument");
+            } else if (fnCandidate.getName().compare("textureGather") == 0) {
+                // More than two arguments needs gpu_shader5, and rectangular or shadow needs gpu_shader5,
+                // otherwise, need GL_ARB_texture_gather.
+                if (fnCandidate.getParamCount() > 2 || fnCandidate[0].type->getSampler().dim == EsdRect || fnCandidate[0].type->getSampler().shadow) {
+                    profileRequires(loc, ~EEsProfile, 400, GL_ARB_gpu_shader5, feature);
+                    if (! fnCandidate[0].type->getSampler().shadow)
+                        compArg = 2;
                 } else
-                    error(loc, "must be a constant", "texture gather component", "");
+                    profileRequires(loc, ~EEsProfile, 400, GL_ARB_texture_gather, feature);
+            }
+
+            if (compArg > 0 && compArg < fnCandidate.getParamCount()) {
+                if (callNode.getSequence()[compArg]->getAsConstantUnion()) {
+                    int value = callNode.getSequence()[compArg]->getAsConstantUnion()->getConstArray()[0].getIConst();
+                    if (value < 0 || value > 3)
+                        error(loc, "must be 0, 1, 2, or 3:", feature, "component argument");
+                } else
+                    error(loc, "must be a compile-time constant:", feature, "component argument");
             }
         } else {
             // this is only for functions not starting "textureGather"...

glslang/MachineIndependent/Scan.cpp

@@ -798,8 +798,9 @@ int TScanContext::tokenizeIdentifier()
     case SAMPLER2DRECT:
     case SAMPLER2DRECTSHADOW:
         afterType = true;
-        if (parseContext.profile == EEsProfile ||
-            (parseContext.profile != EEsProfile && parseContext.version < 140))
+        if (parseContext.profile == EEsProfile)
+            reservedWord();
+        else if (parseContext.version < 140 && ! parseContext.symbolTable.atBuiltInLevel() && ! parseContext.extensionsTurnedOn(1, &GL_ARB_texture_rectangle))
             reservedWord();
         return keyword;
 

glslang/MachineIndependent/Versions.cpp

@@ -157,8 +157,9 @@ void TParseContext::initializeExtensionBehavior()
 
     extensionBehavior[GL_ARB_texture_rectangle]        = EBhDisable;
     extensionBehavior[GL_3DL_array_objects]            = EBhDisable;
-    extensionBehavior[GL_ARB_shading_language_420pack] = EBhDisable;
+    extensionBehavior[GL_ARB_shading_language_420pack] = EBhDisablePartial;
     extensionBehavior[GL_ARB_texture_gather]           = EBhDisable;
+    extensionBehavior[GL_ARB_gpu_shader5]              = EBhDisablePartial;
     extensionBehavior[GL_ARB_separate_shader_objects]  = EBhDisable;
 }
 
@@ -180,6 +181,7 @@ const char* TParseContext::getPreamble()
             "#define GL_ARB_texture_rectangle 1\n"
             "#define GL_ARB_shading_language_420pack 1\n"
             "#define GL_ARB_texture_gather 1\n"
+            "#define GL_ARB_gpu_shader5 1\n"
             "#define GL_ARB_separate_shader_objects 1\n";
     }
 }
@@ -435,8 +437,11 @@ void TParseContext::updateExtensionBehavior(const char* extension, const char* b
             }
 
             return;
-        } else
+        } else {
+            if (iter->second == EBhDisablePartial)
+                warn(getCurrentLoc(), "extension is only partially supported:", "#extension", extension);
             iter->second = behavior;
+        }
     }
 }
 

glslang/MachineIndependent/Versions.h

@@ -65,7 +65,8 @@ typedef enum {
     EBhRequire,
     EBhEnable,
     EBhWarn,
-    EBhDisable
+    EBhDisable,
+    EBhDisablePartial    // use as initial state of an extension that is only partially implemented
 } TExtensionBehavior;
 
 //
@@ -82,6 +83,7 @@ const char* const GL_ARB_texture_rectangle        = "GL_ARB_texture_rectangle";
 const char* const GL_3DL_array_objects            = "GL_3DL_array_objects";
 const char* const GL_ARB_shading_language_420pack = "GL_ARB_shading_language_420pack";
 const char* const GL_ARB_texture_gather           = "GL_ARB_texture_gather";
+const char* const GL_ARB_gpu_shader5              = "GL_ARB_gpu_shader5";
 const char* const GL_ARB_separate_shader_objects  = "GL_ARB_separate_shader_objects";
 
 } // end namespace glslang

glslang/MachineIndependent/glslang.y

@@ -1717,29 +1717,21 @@ type_specifier_nonarray
         $$.sampler.set(EbtUint, EsdCube, true);
     }
     | SAMPLER2DRECT {
-        parseContext.profileRequires($1.loc, ENoProfile, 140, GL_ARB_texture_rectangle, "rectangle texture");
-
         $$.init($1.loc, parseContext.symbolTable.atGlobalLevel());
         $$.basicType = EbtSampler;
         $$.sampler.set(EbtFloat, EsdRect);
     }
     | SAMPLER2DRECTSHADOW {
-        parseContext.profileRequires($1.loc, ECoreProfile, 140, GL_ARB_texture_rectangle, "rectangle texture");
-
         $$.init($1.loc, parseContext.symbolTable.atGlobalLevel());
         $$.basicType = EbtSampler;
         $$.sampler.set(EbtFloat, EsdRect, false, true);
     }
     | ISAMPLER2DRECT {
-        parseContext.profileRequires($1.loc, ECoreProfile, 140, GL_ARB_texture_rectangle, "rectangle texture");
-
         $$.init($1.loc, parseContext.symbolTable.atGlobalLevel());
         $$.basicType = EbtSampler;
         $$.sampler.set(EbtInt, EsdRect);
     }
     | USAMPLER2DRECT {
-        parseContext.profileRequires($1.loc, ECoreProfile, 140, GL_ARB_texture_rectangle, "rectangle texture");
-
         $$.init($1.loc, parseContext.symbolTable.atGlobalLevel());
         $$.basicType = EbtSampler;
         $$.sampler.set(EbtUint, EsdRect);