OutputGLSL.cpp 23.7 KB
Newer Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
//
// Copyright (c) 2002-2010 The ANGLE Project Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//

#include "compiler/OutputGLSL.h"
#include "compiler/debug.h"

namespace
{
TString getTypeName(const TType& type)
{
    TInfoSinkBase out;
    if (type.isMatrix())
    {
        out << "mat";
        out << type.getNominalSize();
    }
    else if (type.isVector())
    {
        switch (type.getBasicType())
        {
            case EbtFloat: out << "vec"; break;
            case EbtInt: out << "ivec"; break;
            case EbtBool: out << "bvec"; break;
            default: UNREACHABLE(); break;
        }
        out << type.getNominalSize();
    }
    else
    {
        if (type.getBasicType() == EbtStruct)
            out << type.getTypeName();
        else
            out << type.getBasicString();
    }
    return TString(out.c_str());
}

TString arrayBrackets(const TType& type)
{
    ASSERT(type.isArray());
    TInfoSinkBase out;
    out << "[" << type.getArraySize() << "]";
    return TString(out.c_str());
}

bool isSingleStatement(TIntermNode* node) {
    if (const TIntermAggregate* aggregate = node->getAsAggregate())
    {
        return (aggregate->getOp() != EOpFunction) &&
               (aggregate->getOp() != EOpSequence);
    }
    else if (const TIntermSelection* selection = node->getAsSelectionNode())
    {
        // Ternary operators are usually part of an assignment operator.
        // This handles those rare cases in which they are all by themselves.
        return selection->usesTernaryOperator();
    }
    else if (node->getAsLoopNode())
    {
        return false;
    }
    return true;
}
}  // namespace

TOutputGLSL::TOutputGLSL(TInfoSinkBase& objSink)
    : TIntermTraverser(true, true, true),
      mObjSink(objSink),
      mDeclaringVariables(false)
{
}

void TOutputGLSL::writeTriplet(Visit visit, const char* preStr, const char* inStr, const char* postStr)
{
    TInfoSinkBase& out = objSink();
    if (visit == PreVisit && preStr)
    {
        out << preStr;
    }
    else if (visit == InVisit && inStr)
    {
        out << inStr;
    }
    else if (visit == PostVisit && postStr)
    {
        out << postStr;
    }
}

void TOutputGLSL::writeVariableType(const TType& type)
{
    TInfoSinkBase& out = objSink();
    TQualifier qualifier = type.getQualifier();
    // TODO(alokp): Validate qualifier for variable declarations.
    if ((qualifier != EvqTemporary) && (qualifier != EvqGlobal))
        out << type.getQualifierString() << " ";

    // Declare the struct if we have not done so already.
    if ((type.getBasicType() == EbtStruct) &&
        (mDeclaredStructs.find(type.getTypeName()) == mDeclaredStructs.end()))
    {
        out << "struct " << type.getTypeName() << "{\n";
        const TTypeList* structure = type.getStruct();
        ASSERT(structure != NULL);
        for (size_t i = 0; i < structure->size(); ++i)
        {
            const TType* fieldType = (*structure)[i].type;
            ASSERT(fieldType != NULL);
            out << getTypeName(*fieldType) << " " << fieldType->getFieldName();
            if (fieldType->isArray())
                out << arrayBrackets(*fieldType);
            out << ";\n";
        }
        out << "}";
        mDeclaredStructs.insert(type.getTypeName());
    }
    else
    {
        out << getTypeName(type);
    }
}

void TOutputGLSL::writeFunctionParameters(const TIntermSequence& args)
{
    TInfoSinkBase& out = objSink();
    for (TIntermSequence::const_iterator iter = args.begin();
         iter != args.end(); ++iter)
    {
        const TIntermSymbol* arg = (*iter)->getAsSymbolNode();
        ASSERT(arg != NULL);

        const TType& type = arg->getType();
        TQualifier qualifier = type.getQualifier();
        // TODO(alokp): Validate qualifier for function arguments.
        if ((qualifier != EvqTemporary) && (qualifier != EvqGlobal))
            out << type.getQualifierString() << " ";

        out << getTypeName(type);

        const TString& name = arg->getSymbol();
        if (!name.empty())
            out << " " << name;
        if (type.isArray())
            out << arrayBrackets(type);

        // Put a comma if this is not the last argument.
150
        if (iter != args.end() - 1)
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
            out << ", ";
    }
}

const ConstantUnion* TOutputGLSL::writeConstantUnion(const TType& type,
                                                     const ConstantUnion* pConstUnion)
{
    TInfoSinkBase& out = objSink();

    if (type.getBasicType() == EbtStruct)
    {
        out << type.getTypeName() << "(";
        const TTypeList* structure = type.getStruct();
        ASSERT(structure != NULL);
        for (size_t i = 0; i < structure->size(); ++i)
        {
            const TType* fieldType = (*structure)[i].type;
            ASSERT(fieldType != NULL);
            pConstUnion = writeConstantUnion(*fieldType, pConstUnion);
            if (i != structure->size() - 1) out << ", ";
        }
        out << ")";
    }
    else
    {
        int size = type.getObjectSize();
        bool writeType = size > 1;
        if (writeType) out << getTypeName(type) << "(";
        for (int i = 0; i < size; ++i, ++pConstUnion)
        {
            switch (pConstUnion->getType())
            {
                case EbtFloat: out << pConstUnion->getFConst(); break;
                case EbtInt: out << pConstUnion->getIConst(); break;
                case EbtBool: out << pConstUnion->getBConst(); break;
                default: UNREACHABLE();
            }
            if (i != size - 1) out << ", ";
        }
        if (writeType) out << ")";
    }
    return pConstUnion;
}

void TOutputGLSL::visitSymbol(TIntermSymbol* node)
{
    TInfoSinkBase& out = objSink();
    out << node->getSymbol();

    if (mDeclaringVariables && node->getType().isArray())
        out << arrayBrackets(node->getType());
}

void TOutputGLSL::visitConstantUnion(TIntermConstantUnion* node)
{
    writeConstantUnion(node->getType(), node->getUnionArrayPointer());
}

bool TOutputGLSL::visitBinary(Visit visit, TIntermBinary* node)
{
    bool visitChildren = true;
    TInfoSinkBase& out = objSink();
    switch (node->getOp())
    {
        case EOpInitialize:
            if (visit == InVisit)
            {
                out << " = ";
                // RHS of initialize is not being declared.
                mDeclaringVariables = false;
            }
            break;
        case EOpAssign: writeTriplet(visit, "(", " = ", ")"); break;
        case EOpAddAssign: writeTriplet(visit, "(", " += ", ")"); break;
        case EOpSubAssign: writeTriplet(visit, "(", " -= ", ")"); break;
        case EOpDivAssign: writeTriplet(visit, "(", " /= ", ")"); break;
        // Notice the fall-through.
        case EOpMulAssign: 
        case EOpVectorTimesMatrixAssign:
        case EOpVectorTimesScalarAssign:
        case EOpMatrixTimesScalarAssign:
        case EOpMatrixTimesMatrixAssign:
            writeTriplet(visit, "(", " *= ", ")");
            break;

        case EOpIndexDirect:
        case EOpIndexIndirect:
            writeTriplet(visit, NULL, "[", "]");
            break;
        case EOpIndexDirectStruct:
            if (visit == InVisit)
            {
                out << ".";
                // TODO(alokp): ASSERT
                out << node->getType().getFieldName();
                visitChildren = false;
            }
            break;
        case EOpVectorSwizzle:
            if (visit == InVisit)
            {
                out << ".";
                TIntermAggregate* rightChild = node->getRight()->getAsAggregate();
                TIntermSequence& sequence = rightChild->getSequence();
                for (TIntermSequence::iterator sit = sequence.begin(); sit != sequence.end(); ++sit)
                {
                    TIntermConstantUnion* element = (*sit)->getAsConstantUnion();
                    ASSERT(element->getBasicType() == EbtInt);
                    ASSERT(element->getNominalSize() == 1);
                    const ConstantUnion& data = element->getUnionArrayPointer()[0];
                    ASSERT(data.getType() == EbtInt);
                    switch (data.getIConst())
                    {
                        case 0: out << "x"; break;
                        case 1: out << "y"; break;
                        case 2: out << "z"; break;
                        case 3: out << "w"; break;
                        default: UNREACHABLE(); break;
                    }
                }
                visitChildren = false;
            }
            break;

        case EOpAdd: writeTriplet(visit, "(", " + ", ")"); break;
        case EOpSub: writeTriplet(visit, "(", " - ", ")"); break;
        case EOpMul: writeTriplet(visit, "(", " * ", ")"); break;
        case EOpDiv: writeTriplet(visit, "(", " / ", ")"); break;
        case EOpMod: UNIMPLEMENTED(); break;
        case EOpEqual: writeTriplet(visit, "(", " == ", ")"); break;
        case EOpNotEqual: writeTriplet(visit, "(", " != ", ")"); break;
        case EOpLessThan: writeTriplet(visit, "(", " < ", ")"); break;
        case EOpGreaterThan: writeTriplet(visit, "(", " > ", ")"); break;
        case EOpLessThanEqual: writeTriplet(visit, "(", " <= ", ")"); break;
        case EOpGreaterThanEqual: writeTriplet(visit, "(", " >= ", ")"); break;

        // Notice the fall-through.
        case EOpVectorTimesScalar:
        case EOpVectorTimesMatrix:
        case EOpMatrixTimesVector:
        case EOpMatrixTimesScalar:
        case EOpMatrixTimesMatrix:
            writeTriplet(visit, "(", " * ", ")");
            break;

        case EOpLogicalOr: writeTriplet(visit, "(", " || ", ")"); break;
        case EOpLogicalXor: writeTriplet(visit, "(", " ^^ ", ")"); break;
        case EOpLogicalAnd: writeTriplet(visit, "(", " && ", ")"); break;
        default: UNREACHABLE(); break;
    }

    return visitChildren;
}

bool TOutputGLSL::visitUnary(Visit visit, TIntermUnary* node)
{
    switch (node->getOp())
    {
        case EOpNegative: writeTriplet(visit, "(-", NULL, ")"); break;
        case EOpVectorLogicalNot: writeTriplet(visit, "not(", NULL, ")"); break;
        case EOpLogicalNot: writeTriplet(visit, "(!", NULL, ")"); break;

        case EOpPostIncrement: writeTriplet(visit, "(", NULL, "++)"); break;
        case EOpPostDecrement: writeTriplet(visit, "(", NULL, "--)"); break;
        case EOpPreIncrement: writeTriplet(visit, "(++", NULL, ")"); break;
        case EOpPreDecrement: writeTriplet(visit, "(--", NULL, ")"); break;

        case EOpConvIntToBool:
        case EOpConvFloatToBool:
            switch (node->getOperand()->getType().getNominalSize())
            {
                case 1: writeTriplet(visit, "bool(", NULL, ")");  break;
                case 2: writeTriplet(visit, "bvec2(", NULL, ")"); break;
                case 3: writeTriplet(visit, "bvec3(", NULL, ")"); break;
                case 4: writeTriplet(visit, "bvec4(", NULL, ")"); break;
                default: UNREACHABLE();
            }
            break;
        case EOpConvBoolToFloat:
        case EOpConvIntToFloat:
            switch (node->getOperand()->getType().getNominalSize())
            {
                case 1: writeTriplet(visit, "float(", NULL, ")");  break;
                case 2: writeTriplet(visit, "vec2(", NULL, ")"); break;
                case 3: writeTriplet(visit, "vec3(", NULL, ")"); break;
                case 4: writeTriplet(visit, "vec4(", NULL, ")"); break;
                default: UNREACHABLE();
            }
            break;
        case EOpConvFloatToInt:
        case EOpConvBoolToInt:
            switch (node->getOperand()->getType().getNominalSize())
            {
                case 1: writeTriplet(visit, "int(", NULL, ")");  break;
                case 2: writeTriplet(visit, "ivec2(", NULL, ")"); break;
                case 3: writeTriplet(visit, "ivec3(", NULL, ")"); break;
                case 4: writeTriplet(visit, "ivec4(", NULL, ")"); break;
                default: UNREACHABLE();
            }
            break;

        case EOpRadians: writeTriplet(visit, "radians(", NULL, ")"); break;
        case EOpDegrees: writeTriplet(visit, "degrees(", NULL, ")"); break;
        case EOpSin: writeTriplet(visit, "sin(", NULL, ")"); break;
        case EOpCos: writeTriplet(visit, "cos(", NULL, ")"); break;
        case EOpTan: writeTriplet(visit, "tan(", NULL, ")"); break;
        case EOpAsin: writeTriplet(visit, "asin(", NULL, ")"); break;
        case EOpAcos: writeTriplet(visit, "acos(", NULL, ")"); break;
        case EOpAtan: writeTriplet(visit, "atan(", NULL, ")"); break;

        case EOpExp: writeTriplet(visit, "exp(", NULL, ")"); break;
        case EOpLog: writeTriplet(visit, "log(", NULL, ")"); break;
        case EOpExp2: writeTriplet(visit, "exp2(", NULL, ")"); break;
        case EOpLog2: writeTriplet(visit, "log2(", NULL, ")"); break;
        case EOpSqrt: writeTriplet(visit, "sqrt(", NULL, ")"); break;
        case EOpInverseSqrt: writeTriplet(visit, "inversesqrt(", NULL, ")"); break;

        case EOpAbs: writeTriplet(visit, "abs(", NULL, ")"); break;
        case EOpSign: writeTriplet(visit, "sign(", NULL, ")"); break;
        case EOpFloor: writeTriplet(visit, "floor(", NULL, ")"); break;
        case EOpCeil: writeTriplet(visit, "ceil(", NULL, ")"); break;
        case EOpFract: writeTriplet(visit, "fract(", NULL, ")"); break;

        case EOpLength: writeTriplet(visit, "length(", NULL, ")"); break;
        case EOpNormalize: writeTriplet(visit, "normalize(", NULL, ")"); break;

        case EOpAny: writeTriplet(visit, "any(", NULL, ")"); break;
        case EOpAll: writeTriplet(visit, "all(", NULL, ")"); break;

        default: UNREACHABLE(); break;
    }

    return true;
}

bool TOutputGLSL::visitSelection(Visit visit, TIntermSelection* node)
{
    TInfoSinkBase& out = objSink();

    if (node->usesTernaryOperator())
    {
392
393
394
395
396
        // Notice two brackets at the beginning and end. The outer ones
        // encapsulate the whole ternary expression. This preserves the
        // order of precedence when ternary expressions are used in a
        // compound expression, i.e., c = 2 * (a < b ? 1 : 2).
        out << "((";
397
398
399
400
401
        node->getCondition()->traverse(this);
        out << ") ? (";
        node->getTrueBlock()->traverse(this);
        out << ") : (";
        node->getFalseBlock()->traverse(this);
402
        out << "))";
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
    }
    else
    {
        out << "if (";
        node->getCondition()->traverse(this);
        out << ")\n";

        incrementDepth();
        visitCodeBlock(node->getTrueBlock());

        if (node->getFalseBlock())
        {
            out << "else\n";
            visitCodeBlock(node->getFalseBlock());
        }
        decrementDepth();
    }
    return false;
}

bool TOutputGLSL::visitAggregate(Visit visit, TIntermAggregate* node)
{
    bool visitChildren = true;
    TInfoSinkBase& out = objSink();
    switch (node->getOp())
    {
        case EOpSequence: {
            // Scope the sequences except when at the global scope.
            if (depth > 0) out << "{\n";

            incrementDepth();
            const TIntermSequence& sequence = node->getSequence();
            for (TIntermSequence::const_iterator iter = sequence.begin();
                 iter != sequence.end(); ++iter)
            {
                TIntermNode* node = *iter;
                ASSERT(node != NULL);
                node->traverse(this);

                if (isSingleStatement(node))
                    out << ";\n";
            }
            decrementDepth();

            // Scope the sequences except when at the global scope.
            if (depth > 0) out << "}\n";
            visitChildren = false;
            break;
        }
        case EOpPrototype: {
            // Function declaration.
            ASSERT(visit == PreVisit);
            TString returnType = getTypeName(node->getType());
            out << returnType << " " << node->getName();

            out << "(";
            writeFunctionParameters(node->getSequence());
            out << ")";

            visitChildren = false;
            break;
        }
        case EOpFunction: {
            // Function definition.
            ASSERT(visit == PreVisit);
            TString returnType = getTypeName(node->getType());
            TString functionName = TFunction::unmangleName(node->getName());
            out << returnType << " " << functionName;

            incrementDepth();
            // Function definition node contains one or two children nodes
            // representing function parameters and function body. The latter
            // is not present in case of empty function bodies.
            const TIntermSequence& sequence = node->getSequence();
            ASSERT((sequence.size() == 1) || (sequence.size() == 2));
            TIntermSequence::const_iterator seqIter = sequence.begin();

            // Traverse function parameters.
            TIntermAggregate* params = (*seqIter)->getAsAggregate();
            ASSERT(params != NULL);
            ASSERT(params->getOp() == EOpParameters);
            params->traverse(this);

            // Traverse function body.
            TIntermAggregate* body = ++seqIter != sequence.end() ?
                (*seqIter)->getAsAggregate() : NULL;
            visitCodeBlock(body);
            decrementDepth();
 
            // Fully processed; no need to visit children.
            visitChildren = false;
            break;
        }
        case EOpFunctionCall:
            // Function call.
            if (visit == PreVisit)
            {
                TString functionName = TFunction::unmangleName(node->getName());
                out << functionName << "(";
            }
            else if (visit == InVisit)
            {
                out << ", ";
            }
            else
            {
                out << ")";
            }
            break;
        case EOpParameters: {
            // Function parameters.
            ASSERT(visit == PreVisit);
            out << "(";
            writeFunctionParameters(node->getSequence());
            out << ")";
            visitChildren = false;
            break;
        }
        case EOpDeclaration: {
            // Variable declaration.
            if (visit == PreVisit)
            {
                const TIntermSequence& sequence = node->getSequence();
                const TIntermTyped* variable = sequence.front()->getAsTyped();
                writeVariableType(variable->getType());
                out << " ";
                mDeclaringVariables = true;
            }
            else if (visit == InVisit)
            {
                out << ", ";
                mDeclaringVariables = true;
            }
            else
            {
                mDeclaringVariables = false;
            }
            break;
        }
        case EOpConstructFloat: writeTriplet(visit, "float(", NULL, ")"); break;
        case EOpConstructVec2: writeTriplet(visit, "vec2(", ", ", ")"); break;
        case EOpConstructVec3: writeTriplet(visit, "vec3(", ", ", ")"); break;
        case EOpConstructVec4: writeTriplet(visit, "vec4(", ", ", ")"); break;
        case EOpConstructBool: writeTriplet(visit, "bool(", NULL, ")"); break;
        case EOpConstructBVec2: writeTriplet(visit, "bvec2(", ", ", ")"); break;
        case EOpConstructBVec3: writeTriplet(visit, "bvec3(", ", ", ")"); break;
        case EOpConstructBVec4: writeTriplet(visit, "bvec4(", ", ", ")"); break;
        case EOpConstructInt: writeTriplet(visit, "int(", NULL, ")"); break;
        case EOpConstructIVec2: writeTriplet(visit, "ivec2(", ", ", ")"); break;
        case EOpConstructIVec3: writeTriplet(visit, "ivec3(", ", ", ")"); break;
        case EOpConstructIVec4: writeTriplet(visit, "ivec4(", ", ", ")"); break;
        case EOpConstructMat2: writeTriplet(visit, "mat2(", ", ", ")"); break;
        case EOpConstructMat3: writeTriplet(visit, "mat3(", ", ", ")"); break;
        case EOpConstructMat4: writeTriplet(visit, "mat4(", ", ", ")"); break;
        case EOpConstructStruct:
            if (visit == PreVisit)
            {
                const TType& type = node->getType();
                ASSERT(type.getBasicType() == EbtStruct);
                out << type.getTypeName() << "(";
            }
            else if (visit == InVisit)
            {
                out << ", ";
            }
            else
            {
                out << ")";
            }
            break;

        case EOpLessThan: writeTriplet(visit, "lessThan(", ", ", ")"); break;
        case EOpGreaterThan: writeTriplet(visit, "greaterThan(", ", ", ")"); break;
        case EOpLessThanEqual: writeTriplet(visit, "lessThanEqual(", ", ", ")"); break;
        case EOpGreaterThanEqual: writeTriplet(visit, "greaterThanEqual(", ", ", ")"); break;
        case EOpVectorEqual: writeTriplet(visit, "equal(", ", ", ")"); break;
        case EOpVectorNotEqual: writeTriplet(visit, "notEqual(", ", ", ")"); break;
        case EOpComma: writeTriplet(visit, NULL, ", ", NULL); break;

        case EOpMod: writeTriplet(visit, "mod(", ", ", ")"); break;
        case EOpPow: writeTriplet(visit, "pow(", ", ", ")"); break;
        case EOpAtan: writeTriplet(visit, "atan(", ", ", ")"); break;
        case EOpMin: writeTriplet(visit, "min(", ", ", ")"); break;
        case EOpMax: writeTriplet(visit, "max(", ", ", ")"); break;
        case EOpClamp: writeTriplet(visit, "clamp(", ", ", ")"); break;
        case EOpMix: writeTriplet(visit, "mix(", ", ", ")"); break;
        case EOpStep: writeTriplet(visit, "step(", ", ", ")"); break;
        case EOpSmoothStep: writeTriplet(visit, "smoothstep(", ", ", ")"); break;

        case EOpDistance: writeTriplet(visit, "distance(", ", ", ")"); break;
        case EOpDot: writeTriplet(visit, "dot(", ", ", ")"); break;
        case EOpCross: writeTriplet(visit, "cross(", ", ", ")"); break;
        case EOpFaceForward: writeTriplet(visit, "faceforward(", ", ", ")"); break;
        case EOpReflect: writeTriplet(visit, "reflect(", ", ", ")"); break;
        case EOpRefract: writeTriplet(visit, "refract(", ", ", ")"); break;
        case EOpMul: writeTriplet(visit, "matrixCompMult(", ", ", ")"); break;

        default: UNREACHABLE(); break;
    }
    return visitChildren;
}

bool TOutputGLSL::visitLoop(Visit visit, TIntermLoop* node)
{
    TInfoSinkBase& out = objSink();

    incrementDepth();
    // Loop header.
    if (node->testFirst())  // for loop
    {
        out << "for (";
        if (node->getInit())
            node->getInit()->traverse(this);
        out << "; ";

        ASSERT(node->getTest() != NULL);
        node->getTest()->traverse(this);
        out << "; ";

        if (node->getTerminal())
            node->getTerminal()->traverse(this);
        out << ")\n";
    }
    else  // do-while loop
    {
        out << "do\n";
    }

    // Loop body.
    visitCodeBlock(node->getBody());

    // Loop footer.
    if (!node->testFirst())  // while loop
    {
        out << "while (";
        ASSERT(node->getTest() != NULL);
        node->getTest()->traverse(this);
        out << ");\n";
    }
    decrementDepth();

    // No need to visit children. They have been already processed in
    // this function.
    return false;
}

bool TOutputGLSL::visitBranch(Visit visit, TIntermBranch* node)
{
    switch (node->getFlowOp())
    {
        case EOpKill: writeTriplet(visit, "discard", NULL, NULL); break;
        case EOpBreak: writeTriplet(visit, "break", NULL, NULL); break;
        case EOpContinue: writeTriplet(visit, "continue", NULL, NULL); break;
        case EOpReturn: writeTriplet(visit, "return ", NULL, NULL); break;
        default: UNREACHABLE(); break;
    }

    return true;
}

void TOutputGLSL::visitCodeBlock(TIntermNode* node) {
    TInfoSinkBase &out = objSink();
    if (node != NULL)
    {
        node->traverse(this);
        // Single statements not part of a sequence need to be terminated
        // with semi-colon.
        if (isSingleStatement(node))
            out << ";\n";
    }
    else
    {
        out << "{\n}\n";  // Empty code block.
    }
}