Implement GL_OES_shader_multisample_interpolation, as well as core desktop versions of it.

Test/310.frag

@@ -341,3 +341,59 @@ void goodImageAtom()
     imageAtomicMax(badIm2Du, P, datu);      // ERROR, not an allowed layout() on the image
     imageAtomicExchange(badIm2Df, P, datf); // ERROR, not an allowed layout() on the image
 }
+
+sample in vec4 colorSampInBad;       // ERROR, reserved
+centroid out vec4 colorCentroidBad;  // ERROR
+flat out vec4 colorBadFlat;          // ERROR
+smooth out vec4 colorBadSmooth;      // ERROR
+noperspective out vec4 colorBadNo;   // ERROR
+flat centroid in vec2 colorfc;
+in float scalarIn;
+
+void badInterp()
+{
+    interpolateAtCentroid(colorfc);             // ERROR, need extension
+    interpolateAtSample(colorfc, 1);            // ERROR, need extension
+    interpolateAtOffset(colorfc, vec2(0.2));    // ERROR, need extension
+}
+
+#if defined GL_OES_shader_multisample_interpolation
+#extension GL_OES_shader_multisample_interpolation : enable
+#endif
+
+sample in vec4 colorSampIn;
+sample out vec4 colorSampleBad;     // ERROR
+flat sample in vec4 colorfsi;
+sample in vec3 sampInArray[4];
+
+void interp()
+{
+    float res;
+    vec2 res2;
+    vec3 res3;
+    vec4 res4;
+
+    res2 = interpolateAtCentroid(colorfc);
+    res4 = interpolateAtCentroid(colorSampIn);
+    res4 = interpolateAtCentroid(colorfsi);
+    res  = interpolateAtCentroid(scalarIn);
+    res3 = interpolateAtCentroid(sampInArray);         // ERROR
+    res3 = interpolateAtCentroid(sampInArray[2]);
+    res2 = interpolateAtCentroid(sampInArray[2].xy);   // ERROR
+
+    res3 = interpolateAtSample(sampInArray, 1);        // ERROR
+    res3 = interpolateAtSample(sampInArray[i], 0);
+    res2 = interpolateAtSample(sampInArray[2].xy, 2);  // ERROR
+    res  = interpolateAtSample(scalarIn, 1);
+
+    res3 = interpolateAtOffset(sampInArray, vec2(0.2));         // ERROR
+    res3 = interpolateAtOffset(sampInArray[2], vec2(0.2));
+    res2 = interpolateAtOffset(sampInArray[2].xy, vec2(0.2));   // ERROR, no swizzle
+    res  = interpolateAtOffset(scalarIn + scalarIn, vec2(0.2)); // ERROR, no binary ops other than dereference
+    res  = interpolateAtOffset(scalarIn, vec2(0.2));
+
+    float f;
+    res  = interpolateAtCentroid(f);           // ERROR, not interpolant
+    res4 = interpolateAtSample(outp, 0);       // ERROR, not interpolant
+}
+

Test/310.vert

@@ -373,3 +373,19 @@ void goodImageAtom()
     imageAtomicCompSwap(im2Di, P,  3, dati);
     imageAtomicCompSwap(im2Du, P, 5u, datu);
 }
+
+sample out vec4 colorSampInBad;       // ERROR, reserved
+
+#extension GL_OES_shader_multisample_interpolation : enable
+
+sample out vec4 colorSample;
+flat sample out vec4 colorfsi;
+sample out vec3 sampInArray[4];
+in vec4 inv4;
+
+void badInterp()
+{
+    interpolateAtCentroid(inv4);             // ERROR, wrong stage
+    interpolateAtSample(inv4, 1);            // ERROR, need extension
+    interpolateAtOffset(inv4, vec2(0.2));    // ERROR, need extension
+}

Test/400.frag

@@ -99,3 +99,43 @@ void foodc2()
     d = packDouble2x32(u2);
     u2 = unpackDouble2x32(d);
 }
+
+sample in vec4 colorSampIn;
+sample out vec4 colorSampleBad;     // ERROR
+noperspective in vec4 colorfsi;
+sample in vec3 sampInArray[4];
+smooth in float scalarIn;
+flat centroid in vec2 colorfc;
+
+struct S {
+    float x;
+};
+
+in S s1;
+sample S s2;
+
+void interp()
+{
+    interpolateAtCentroid(colorfc);
+    interpolateAtCentroid(colorSampIn);
+    interpolateAtCentroid(colorfsi);
+    interpolateAtCentroid(scalarIn);
+    interpolateAtCentroid(sampInArray);         // ERROR
+    interpolateAtCentroid(sampInArray[2]);
+    interpolateAtCentroid(sampInArray[2].xy);   // ERROR
+
+    interpolateAtSample(sampInArray, 1);        // ERROR
+    interpolateAtSample(sampInArray[i], 0);
+    interpolateAtSample(s1.x, 2);               // ERROR
+    interpolateAtSample(scalarIn, 1);
+
+    interpolateAtOffset(sampInArray, vec2(0.2));         // ERROR
+    interpolateAtOffset(sampInArray[2], vec2(0.2));
+    interpolateAtOffset(sampInArray[2].xy, vec2(0.2));   // ERROR, no swizzle
+    interpolateAtOffset(scalarIn + scalarIn, vec2(0.2)); // ERROR, no binary ops other than dereference
+    interpolateAtOffset(s2.x, vec2(0.2));      // ERROR
+
+    float f;
+    interpolateAtCentroid(f);           // ERROR, not interpolant
+    interpolateAtSample(outp, 0);       // ERROR, not interpolant
+}
\ No newline at end of file

Test/440.frag

@@ -138,3 +138,10 @@ layout(std430, align = 128) uniform block24301 {
 
 int aconst[gl_MaxTransformFeedbackBuffers];
 int bconst[gl_MaxTransformFeedbackInterleavedComponents];
+
+sample in vec3 sampInArray[4];
+
+void interp()
+{
+    interpolateAtCentroid(sampInArray[2].xy);
+}

Test/baseResults/310.vert.out

@@ -90,7 +90,11 @@ ERROR: 0:318: 'sampler/image' : type requires declaration of default precision q
 ERROR: 0:319: 'sampler/image' : type requires declaration of default precision qualifier 
 ERROR: 0:339: 'textureSize' : no matching overloaded function found 
 ERROR: 0:339: '=' :  cannot convert from 'const float' to 'temp highp 3-component vector of int'
-ERROR: 86 compilation errors.  No code generated.
+ERROR: 0:377: 'sample' : Reserved word. 
+ERROR: 0:388: 'interpolateAtCentroid' : no matching overloaded function found 
+ERROR: 0:389: 'interpolateAtSample' : no matching overloaded function found 
+ERROR: 0:390: 'interpolateAtOffset' : no matching overloaded function found 
+ERROR: 90 compilation errors.  No code generated.
 
 
 Shader version: 310
@@ -98,6 +102,7 @@ Requested GL_EXT_texture_buffer
 Requested GL_OES_gpu_shader5
 Requested GL_OES_shader_image_atomic
 Requested GL_OES_shader_io_blocks
+Requested GL_OES_shader_multisample_interpolation
 Requested GL_OES_texture_buffer
 Requested GL_OES_texture_cube_map_array
 Requested GL_OES_texture_storage_multisample_2d_array
@@ -852,6 +857,15 @@ ERROR: node is still EOpNull!
 0:374        Constant:
 0:374          5 (const uint)
 0:374        'datu' (temp highp uint)
+0:386  Function Definition: badInterp( (global void)
+0:386    Function Parameters: 
+0:388    Sequence
+0:388      Constant:
+0:388        0.000000
+0:389      Constant:
+0:389        0.000000
+0:390      Constant:
+0:390        0.000000
 0:?   Linker Objects
 0:?     's' (shared highp 4-component vector of float)
 0:?     'v' (buffer highp 4-component vector of float)
@@ -953,6 +967,11 @@ ERROR: node is still EOpNull!
 0:?     'im2Du' (layout(r32ui ) uniform highp uimage2D)
 0:?     'im2Di' (layout(r32i ) uniform highp iimage2D)
 0:?     'P' (uniform highp 2-component vector of int)
+0:?     'colorSampInBad' (smooth sample out highp 4-component vector of float)
+0:?     'colorSample' (smooth sample out highp 4-component vector of float)
+0:?     'colorfsi' (flat sample out highp 4-component vector of float)
+0:?     'sampInArray' (smooth sample out 4-element array of highp 3-component vector of float)
+0:?     'inv4' (in highp 4-component vector of float)
 0:?     'gl_VertexID' (gl_VertexId highp int VertexId)
 0:?     'gl_InstanceID' (gl_InstanceId highp int InstanceId)
 
@@ -965,6 +984,7 @@ Requested GL_EXT_texture_buffer
 Requested GL_OES_gpu_shader5
 Requested GL_OES_shader_image_atomic
 Requested GL_OES_shader_io_blocks
+Requested GL_OES_shader_multisample_interpolation
 Requested GL_OES_texture_buffer
 Requested GL_OES_texture_cube_map_array
 Requested GL_OES_texture_storage_multisample_2d_array
@@ -1719,6 +1739,15 @@ ERROR: node is still EOpNull!
 0:374        Constant:
 0:374          5 (const uint)
 0:374        'datu' (temp highp uint)
+0:386  Function Definition: badInterp( (global void)
+0:386    Function Parameters: 
+0:388    Sequence
+0:388      Constant:
+0:388        0.000000
+0:389      Constant:
+0:389        0.000000
+0:390      Constant:
+0:390        0.000000
 0:?   Linker Objects
 0:?     's' (shared highp 4-component vector of float)
 0:?     'v' (buffer highp 4-component vector of float)
@@ -1820,6 +1849,11 @@ ERROR: node is still EOpNull!
 0:?     'im2Du' (layout(r32ui ) uniform highp uimage2D)
 0:?     'im2Di' (layout(r32i ) uniform highp iimage2D)
 0:?     'P' (uniform highp 2-component vector of int)
+0:?     'colorSampInBad' (smooth sample out highp 4-component vector of float)
+0:?     'colorSample' (smooth sample out highp 4-component vector of float)
+0:?     'colorfsi' (flat sample out highp 4-component vector of float)
+0:?     'sampInArray' (smooth sample out 4-element array of highp 3-component vector of float)
+0:?     'inv4' (in highp 4-component vector of float)
 0:?     'gl_VertexID' (gl_VertexId highp int VertexId)
 0:?     'gl_InstanceID' (gl_InstanceId highp int InstanceId)
 

Test/baseResults/440.frag.out

@@ -53,6 +53,20 @@ ERROR: 48 compilation errors.  No code generated.
 
 Shader version: 440
 ERROR: node is still EOpNull!
+0:144  Function Definition: interp( (global void)
+0:144    Function Parameters: 
+0:146    Sequence
+0:146      interpolateAtCentroid (global 2-component vector of float)
+0:146        vector swizzle (temp 2-component vector of float)
+0:146          direct index (smooth sample temp 3-component vector of float)
+0:146            'sampInArray' (smooth sample in 4-element array of 3-component vector of float)
+0:146            Constant:
+0:146              2 (const int)
+0:146          Sequence
+0:146            Constant:
+0:146              0 (const int)
+0:146            Constant:
+0:146              1 (const int)
 0:?   Linker Objects
 0:?     'a' (layout(location=4 component=2 ) smooth in 2-component vector of float)
 0:?     'b' (layout(location=4 component=1 ) smooth in float)
@@ -88,6 +102,7 @@ ERROR: node is still EOpNull!
 0:?     'specExample4301' (layout(column_major std430 align=128 ) uniform block{layout(column_major std430 offset=0 align=128 ) uniform 4-component vector of float a, layout(column_major std430 offset=128 align=128 ) uniform 3-component vector of float b, layout(column_major std430 offset=256 align=128 ) uniform 2-component vector of float d, layout(column_major std430 offset=512 align=128 ) uniform float e, layout(column_major std430 offset=520 align=8 ) uniform double f, layout(column_major std430 offset=640 align=128 ) uniform float h, layout(column_major std430 offset=768 align=128 ) uniform 3-component vector of double i})
 0:?     'aconst' (global 4-element array of int)
 0:?     'bconst' (global 64-element array of int)
+0:?     'sampInArray' (smooth sample in 4-element array of 3-component vector of float)
 
 
 Linked fragment stage:
@@ -96,6 +111,20 @@ ERROR: Linking fragment stage: Missing entry point: Each stage requires one "voi
 
 Shader version: 440
 ERROR: node is still EOpNull!
+0:144  Function Definition: interp( (global void)
+0:144    Function Parameters: 
+0:146    Sequence
+0:146      interpolateAtCentroid (global 2-component vector of float)
+0:146        vector swizzle (temp 2-component vector of float)
+0:146          direct index (smooth sample temp 3-component vector of float)
+0:146            'sampInArray' (smooth sample in 4-element array of 3-component vector of float)
+0:146            Constant:
+0:146              2 (const int)
+0:146          Sequence
+0:146            Constant:
+0:146              0 (const int)
+0:146            Constant:
+0:146              1 (const int)
 0:?   Linker Objects
 0:?     'a' (layout(location=4 component=2 ) smooth in 2-component vector of float)
 0:?     'b' (layout(location=4 component=1 ) smooth in float)
@@ -131,4 +160,5 @@ ERROR: node is still EOpNull!
 0:?     'specExample4301' (layout(column_major std430 align=128 ) uniform block{layout(column_major std430 offset=0 align=128 ) uniform 4-component vector of float a, layout(column_major std430 offset=128 align=128 ) uniform 3-component vector of float b, layout(column_major std430 offset=256 align=128 ) uniform 2-component vector of float d, layout(column_major std430 offset=512 align=128 ) uniform float e, layout(column_major std430 offset=520 align=8 ) uniform double f, layout(column_major std430 offset=640 align=128 ) uniform float h, layout(column_major std430 offset=768 align=128 ) uniform 3-component vector of double i})
 0:?     'aconst' (global 4-element array of int)
 0:?     'bconst' (global 64-element array of int)
+0:?     'sampInArray' (smooth sample in 4-element array of 3-component vector of float)
 

glslang/Include/intermediate.h

@@ -226,6 +226,10 @@ enum TOperator {
     EOpDPdyCoarse,      // Fragment only
     EOpFwidthCoarse,    // Fragment only
 
+    EOpInterpolateAtCentroid, // Fragment only
+    EOpInterpolateAtSample,   // Fragment only
+    EOpInterpolateAtOffset,   // Fragment only
+
     EOpMatrixTimesMatrix,
     EOpOuterProduct,
     EOpDeterminant,

glslang/Include/revision.h

@@ -2,5 +2,5 @@
 // For the version, it uses the latest git tag followed by the number of commits.
 // For the date, it uses the current date (when then script is run).
 
-#define GLSLANG_REVISION "3.0.730"
-#define GLSLANG_DATE "21-Aug-2015"
+#define GLSLANG_REVISION "3.0.732"
+#define GLSLANG_DATE "22-Aug-2015"

glslang/MachineIndependent/Initialize.cpp

@@ -1185,6 +1185,28 @@ void TBuiltIns::initialize(int version, EProfile profile)
             "\n");
     }
 
+    // GL_OES_shader_multisample_interpolation
+    if ((profile == EEsProfile && version >= 310) ||
+        (profile != EEsProfile && version >= 400)) {
+        stageBuiltins[EShLangFragment].append(
+            "float interpolateAtCentroid(float);"
+            "vec2  interpolateAtCentroid(vec2);"
+            "vec3  interpolateAtCentroid(vec3);"
+            "vec4  interpolateAtCentroid(vec4);"
+
+            "float interpolateAtSample(float, int);"
+            "vec2  interpolateAtSample(vec2,  int);"
+            "vec3  interpolateAtSample(vec3,  int);"
+            "vec4  interpolateAtSample(vec4,  int);"
+
+            "float interpolateAtOffset(float, vec2);"
+            "vec2  interpolateAtOffset(vec2,  vec2);"
+            "vec3  interpolateAtOffset(vec3,  vec2);"
+            "vec4  interpolateAtOffset(vec4,  vec2);"
+
+            "\n");
+    }
+
     //============================================================================
     //
     // Standard Uniforms
@@ -3009,8 +3031,12 @@ void IdentifyBuiltIns(int version, EProfile profile, EShLanguage language, TSymb
                 symbolTable.setFunctionExtensions("dFdy",   1, &E_GL_OES_standard_derivatives);
                 symbolTable.setFunctionExtensions("fwidth", 1, &E_GL_OES_standard_derivatives);
             }
-            if (version >= 310)
+            if (version >= 310) {
                 symbolTable.setFunctionExtensions("fma", Num_AEP_gpu_shader5, AEP_gpu_shader5);
+                symbolTable.setFunctionExtensions("interpolateAtCentroid", 1, &E_GL_OES_shader_multisample_interpolation);
+                symbolTable.setFunctionExtensions("interpolateAtSample",   1, &E_GL_OES_shader_multisample_interpolation);
+                symbolTable.setFunctionExtensions("interpolateAtOffset",   1, &E_GL_OES_shader_multisample_interpolation);
+            }
         } else if (version < 130) {
             symbolTable.setFunctionExtensions("texture1DLod",        1, &E_GL_ARB_shader_texture_lod);
             symbolTable.setFunctionExtensions("texture2DLod",        1, &E_GL_ARB_shader_texture_lod);
@@ -3351,6 +3377,9 @@ void IdentifyBuiltIns(int version, EProfile profile, EShLanguage language, TSymb
             symbolTable.relateToOperator("dFdyCoarse",   EOpDPdyCoarse);
             symbolTable.relateToOperator("fwidthCoarse", EOpFwidthCoarse);
         }
+        symbolTable.relateToOperator("interpolateAtCentroid", EOpInterpolateAtCentroid);
+        symbolTable.relateToOperator("interpolateAtSample",   EOpInterpolateAtSample);
+        symbolTable.relateToOperator("interpolateAtOffset",   EOpInterpolateAtOffset);
         break;
 
     case EShLangCompute:

glslang/MachineIndependent/Intermediate.cpp

@@ -861,6 +861,35 @@ TIntermTyped* TIntermediate::addSwizzle(TVectorFields& fields, const TSourceLoc&
 }
 
 //
+// Follow the left branches down to the root of an l-value
+// expression (just "." and []).
+//
+// Return the base of the l-value (where following indexing quits working).
+// Return nullptr if a chain following dereferences cannot be followed.
+//
+// 'swizzleOkay' says whether or not it is okay to consider a swizzle 
+// a valid part of the dereference chain.
+//
+const TIntermTyped* TIntermediate::findLValueBase(const TIntermTyped* node, bool swizzleOkay)
+{
+    do {
+        const TIntermBinary* binary = node->getAsBinaryNode();
+        if (binary == nullptr)
+            return node;
+        TOperator op = binary->getOp();
+        if (op != EOpIndexDirect && op != EOpIndexIndirect && op != EOpIndexDirectStruct && op != EOpVectorSwizzle)
+            return nullptr;
+        if (! swizzleOkay) {
+            if (op == EOpVectorSwizzle)
+                return nullptr;
+            if ((op == EOpIndexDirect || op == EOpIndexIndirect) && binary->getLeft()->getType().isVector() && ! binary->getLeft()->getType().isArray())
+                return nullptr;
+        }
+        node = node->getAsBinaryNode()->getLeft();
+    } while (true);
+}
+
+//
 // Create loop nodes.
 //
 TIntermLoop* TIntermediate::addLoop(TIntermNode* body, TIntermTyped* test, TIntermTyped* terminal, bool testFirst, const TSourceLoc& loc)

glslang/MachineIndependent/ParseHelper.cpp

@@ -1485,6 +1485,30 @@ void TParseContext::builtInOpCheck(const TSourceLoc& loc, const TFunction& fnCan
         break;
     }
 
+    case EOpInterpolateAtCentroid:
+    case EOpInterpolateAtSample:
+    case EOpInterpolateAtOffset:
+        // "For the interpolateAt* functions, the call will return a precision
+        // qualification matching the precision of the 'interpolant' argument to
+        // the function call."
+        callNode.getQualifier().precision = arg0->getQualifier().precision;
+
+        // Make sure the first argument is an interpolant, or an array element of an interpolant
+        if (arg0->getType().getQualifier().storage != EvqVaryingIn) {
+            // It might still be an array element.
+            //
+            // We could check more, but the semantics of the first argument are already met; the
+            // only way to turn an array into a float/vec* is array dereference and swizzle.
+            //
+            // ES and desktop 4.3 and earlier:  swizzles may not be used
+            // desktop 4.4 and later: swizzles may be used
+            bool swizzleOkay = (profile != EEsProfile) && (version >= 440);
+            const TIntermTyped* base = TIntermediate::findLValueBase(arg0, swizzleOkay);
+            if (base == nullptr || base->getType().getQualifier().storage != EvqVaryingIn)
+                error(loc, "first argument must be an interpolant, or interpolant-array element", fnCandidate.getName().c_str(), "");
+        }
+        break;
+
     default:
         break;
     }
@@ -2456,6 +2480,10 @@ void TParseContext::globalQualifierTypeCheck(const TSourceLoc& loc, const TQuali
                 error(loc, "cannot be a matrix", GetStorageQualifierString(qualifier.storage), "");
                 return;
             }
+            if (qualifier.isAuxiliary())
+                error(loc, "can't use auxiliary qualifier on a fragment output", "centroid/sample/patch", "");
+            if (qualifier.isInterpolation())
+                error(loc, "can't use interpolation qualifier on a fragment output", "flat/smooth/noperspective", "");
         break;
 
         case EShLangCompute:

glslang/MachineIndependent/Scan.cpp

@@ -738,6 +738,10 @@ int TScanContext::tokenizeIdentifier()
         return es30ReservedFromGLSL(400);
 
     case SAMPLE:
+        if (parseContext.extensionsTurnedOn(1, &E_GL_OES_shader_multisample_interpolation))
+            return keyword;
+        return es30ReservedFromGLSL(400);
+
     case SUBROUTINE:
         return es30ReservedFromGLSL(400);
 

glslang/MachineIndependent/Versions.cpp

@@ -183,7 +183,7 @@ void TParseContext::initializeExtensionBehavior()
     extensionBehavior[E_GL_KHR_blend_equation_advanced]              = EBhDisablePartial;
     extensionBehavior[E_GL_OES_sample_variables]                     = EBhDisable;
     extensionBehavior[E_GL_OES_shader_image_atomic]                  = EBhDisable;
-    extensionBehavior[E_GL_OES_shader_multisample_interpolation]     = EBhDisablePartial;
+    extensionBehavior[E_GL_OES_shader_multisample_interpolation]     = EBhDisable;
     extensionBehavior[E_GL_OES_texture_storage_multisample_2d_array] = EBhDisable;
     extensionBehavior[E_GL_EXT_geometry_shader]                      = EBhDisable;
     extensionBehavior[E_GL_EXT_geometry_point_size]                  = EBhDisable;

glslang/MachineIndependent/intermOut.cpp

@@ -286,6 +286,9 @@ bool TOutputTraverser::visitUnary(TVisit /* visit */, TIntermUnary* node)
     case EOpDPdxCoarse:     out.debug << "dPdxCoarse";           break;
     case EOpDPdyCoarse:     out.debug << "dPdyCoarse";           break;
     case EOpFwidthCoarse:   out.debug << "fwidthCoarse";         break;
+
+    case EOpInterpolateAtCentroid: out.debug << "interpolateAtCentroid";  break;
+
     case EOpDeterminant:    out.debug << "determinant";          break;
     case EOpMatrixInverse:  out.debug << "inverse";              break;
     case EOpTranspose:      out.debug << "transpose";            break;
@@ -473,8 +476,11 @@ bool TOutputTraverser::visitAggregate(TVisit /* visit */, TIntermAggregate* node
     case EOpBitfieldInsert:             out.debug << "bitfieldInsert";        break;
 
     case EOpFma:                        out.debug << "fma";                   break;
-    case EOpFrexp:                        out.debug << "frexp";                 break;
-    case EOpLdexp:                        out.debug << "ldexp";                 break;
+    case EOpFrexp:                      out.debug << "frexp";                 break;
+    case EOpLdexp:                      out.debug << "ldexp";                 break;
+
+    case EOpInterpolateAtSample:   out.debug << "interpolateAtSample";    break;
+    case EOpInterpolateAtOffset:   out.debug << "interpolateAtOffset";    break;
 
     default: out.debug.message(EPrefixError, "Bad aggregation op");
     }

glslang/MachineIndependent/localintermediate.h

@@ -192,6 +192,9 @@ public:
     TIntermTyped* foldDereference(TIntermTyped* node, int index, const TSourceLoc&);
     TIntermTyped* foldSwizzle(TIntermTyped* node, TVectorFields& fields, const TSourceLoc&);
 
+    // Tree ops
+    static const TIntermTyped* findLValueBase(const TIntermTyped*, bool swizzleOkay);
+
     // Linkage related
     void addSymbolLinkageNodes(TIntermAggregate*& linkage, EShLanguage, TSymbolTable&);
     void addSymbolLinkageNode(TIntermAggregate*& linkage, TSymbolTable&, const TString&);