• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright 2020 Google LLC
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #include "src/sksl/SkSLDehydrator.h"
9 
10 #include <map>
11 
12 #include "include/private/SkSLProgramElement.h"
13 #include "include/private/SkSLStatement.h"
14 #include "include/private/SkSLSymbol.h"
15 #include "src/sksl/SkSLRehydrator.h"
16 #include "src/sksl/ir/SkSLBinaryExpression.h"
17 #include "src/sksl/ir/SkSLBreakStatement.h"
18 #include "src/sksl/ir/SkSLConstructor.h"
19 #include "src/sksl/ir/SkSLConstructorArray.h"
20 #include "src/sksl/ir/SkSLConstructorArrayCast.h"
21 #include "src/sksl/ir/SkSLConstructorCompound.h"
22 #include "src/sksl/ir/SkSLConstructorCompoundCast.h"
23 #include "src/sksl/ir/SkSLConstructorDiagonalMatrix.h"
24 #include "src/sksl/ir/SkSLConstructorMatrixResize.h"
25 #include "src/sksl/ir/SkSLConstructorScalarCast.h"
26 #include "src/sksl/ir/SkSLConstructorSplat.h"
27 #include "src/sksl/ir/SkSLConstructorStruct.h"
28 #include "src/sksl/ir/SkSLContinueStatement.h"
29 #include "src/sksl/ir/SkSLDiscardStatement.h"
30 #include "src/sksl/ir/SkSLDoStatement.h"
31 #include "src/sksl/ir/SkSLExpressionStatement.h"
32 #include "src/sksl/ir/SkSLField.h"
33 #include "src/sksl/ir/SkSLFieldAccess.h"
34 #include "src/sksl/ir/SkSLForStatement.h"
35 #include "src/sksl/ir/SkSLFunctionCall.h"
36 #include "src/sksl/ir/SkSLFunctionDeclaration.h"
37 #include "src/sksl/ir/SkSLFunctionDefinition.h"
38 #include "src/sksl/ir/SkSLFunctionPrototype.h"
39 #include "src/sksl/ir/SkSLIfStatement.h"
40 #include "src/sksl/ir/SkSLIndexExpression.h"
41 #include "src/sksl/ir/SkSLInlineMarker.h"
42 #include "src/sksl/ir/SkSLInterfaceBlock.h"
43 #include "src/sksl/ir/SkSLLiteral.h"
44 #include "src/sksl/ir/SkSLPostfixExpression.h"
45 #include "src/sksl/ir/SkSLPrefixExpression.h"
46 #include "src/sksl/ir/SkSLReturnStatement.h"
47 #include "src/sksl/ir/SkSLSetting.h"
48 #include "src/sksl/ir/SkSLStructDefinition.h"
49 #include "src/sksl/ir/SkSLSwitchCase.h"
50 #include "src/sksl/ir/SkSLSwitchStatement.h"
51 #include "src/sksl/ir/SkSLSwizzle.h"
52 #include "src/sksl/ir/SkSLSymbolTable.h"
53 #include "src/sksl/ir/SkSLTernaryExpression.h"
54 #include "src/sksl/ir/SkSLUnresolvedFunction.h"
55 #include "src/sksl/ir/SkSLVarDeclarations.h"
56 #include "src/sksl/ir/SkSLVariable.h"
57 
58 namespace SkSL {
59 
60 static constexpr int HEADER_SIZE = 2;
61 
62 class AutoDehydratorSymbolTable {
63 public:
AutoDehydratorSymbolTable(Dehydrator * dehydrator,const std::shared_ptr<SymbolTable> & symbols)64     AutoDehydratorSymbolTable(Dehydrator* dehydrator, const std::shared_ptr<SymbolTable>& symbols)
65         : fDehydrator(dehydrator) {
66         dehydrator->fSymbolMap.emplace_back();
67         if (symbols) {
68             dehydrator->write(*symbols);
69         } else {
70             dehydrator->writeCommand(Rehydrator::kVoid_Command);
71         }
72     }
73 
~AutoDehydratorSymbolTable()74     ~AutoDehydratorSymbolTable() {
75         fDehydrator->fSymbolMap.pop_back();
76     }
77 
78 private:
79     Dehydrator* fDehydrator;
80 };
81 
writeId(const Symbol * s)82 void Dehydrator::writeId(const Symbol* s) {
83     uint16_t id = this->symbolId(s);
84     if (id) {
85         this->writeU16(id);
86     } else {
87         this->writeU16(Rehydrator::kBuiltin_Symbol);
88         this->write(s->name());
89     }
90 }
91 
write(Layout l)92 void Dehydrator::write(Layout l) {
93     if (l == Layout()) {
94         this->writeCommand(Rehydrator::kDefaultLayout_Command);
95     } else if (l == Layout::builtin(l.fBuiltin)) {
96         this->writeCommand(Rehydrator::kBuiltinLayout_Command);
97         this->writeS16(l.fBuiltin);
98     } else {
99         this->writeCommand(Rehydrator::kLayout_Command);
100         fBody.write32(l.fFlags);
101         this->writeS8(l.fLocation);
102         this->writeS16(l.fOffset);
103         this->writeS16(l.fBinding);
104         this->writeS8(l.fIndex);
105         this->writeS8(l.fSet);
106         this->writeS16(l.fBuiltin);
107         this->writeS8(l.fInputAttachmentIndex);
108     }
109 }
110 
write(Modifiers m)111 void Dehydrator::write(Modifiers m) {
112     if (m == Modifiers()) {
113         this->writeCommand(Rehydrator::kDefaultModifiers_Command);
114     } else {
115         if (m.fFlags <= 255) {
116             this->writeCommand(Rehydrator::kModifiers8Bit_Command);
117             this->write(m.fLayout);
118             this->writeU8(m.fFlags);
119         } else {
120             this->writeCommand(Rehydrator::kModifiers_Command);
121             this->write(m.fLayout);
122             this->writeS32(m.fFlags);
123         }
124     }
125 }
126 
write(std::string_view s)127 void Dehydrator::write(std::string_view s) {
128     this->write(std::string(s));
129 }
130 
write(std::string s)131 void Dehydrator::write(std::string s) {
132     auto found = fStrings.find(s);
133     int offset;
134     if (found == fStrings.end()) {
135         offset = fStringBuffer.bytesWritten() + HEADER_SIZE;
136         fStrings.insert({ s, offset });
137         SkASSERT(s.length() <= 255);
138         fStringBreaks.add(fStringBuffer.bytesWritten());
139         fStringBuffer.write8(s.length());
140         fStringBuffer.writeString(s);
141     } else {
142         offset = found->second;
143     }
144     this->writeU16(offset);
145 }
146 
write(const Symbol & s)147 void Dehydrator::write(const Symbol& s) {
148     uint16_t id = this->symbolId(&s);
149     if (id) {
150         this->writeCommand(Rehydrator::kSymbolRef_Command);
151         this->writeU16(id);
152         return;
153     }
154     switch (s.kind()) {
155         case Symbol::Kind::kFunctionDeclaration: {
156             this->allocSymbolId(&s);
157             const FunctionDeclaration& f = s.as<FunctionDeclaration>();
158             this->writeCommand(Rehydrator::kFunctionDeclaration_Command);
159             this->writeId(&f);
160             this->write(f.modifiers());
161             this->write(f.name());
162             this->writeU8(f.parameters().size());
163             for (const Variable* p : f.parameters()) {
164                 this->writeU16(this->symbolId(p));
165             }
166             this->write(f.returnType());
167             break;
168         }
169         case Symbol::Kind::kUnresolvedFunction: {
170             this->allocSymbolId(&s);
171             const UnresolvedFunction& f = s.as<UnresolvedFunction>();
172             this->writeCommand(Rehydrator::kUnresolvedFunction_Command);
173             this->writeId(&f);
174             this->writeU8(f.functions().size());
175             for (const FunctionDeclaration* funcDecl : f.functions()) {
176                 this->write(*funcDecl);
177             }
178             break;
179         }
180         case Symbol::Kind::kType: {
181             const Type& t = s.as<Type>();
182             switch (t.typeKind()) {
183                 case Type::TypeKind::kArray:
184                     this->allocSymbolId(&s);
185                     this->writeCommand(Rehydrator::kArrayType_Command);
186                     this->writeId(&t);
187                     this->write(t.componentType());
188                     this->writeS8(t.columns());
189                     break;
190                 case Type::TypeKind::kStruct:
191                     this->allocSymbolId(&s);
192                     this->writeCommand(Rehydrator::kStructType_Command);
193                     this->writeId(&t);
194                     this->write(t.name());
195                     this->writeU8(t.fields().size());
196                     for (const Type::Field& f : t.fields()) {
197                         this->write(f.fModifiers);
198                         this->write(f.fName);
199                         this->write(*f.fType);
200                     }
201                     this->writeU8(t.isInterfaceBlock());
202                     break;
203                 default:
204                     this->writeCommand(Rehydrator::kSymbolRef_Command);
205                     this->writeU16(Rehydrator::kBuiltin_Symbol);
206                     this->write(t.name());
207                     break;
208             }
209             break;
210         }
211         case Symbol::Kind::kVariable: {
212             this->allocSymbolId(&s);
213             const Variable& v = s.as<Variable>();
214             this->writeCommand(Rehydrator::kVariable_Command);
215             this->writeId(&v);
216             this->write(v.modifiers());
217             this->write(v.name());
218             this->write(v.type());
219             this->writeU8((int8_t) v.storage());
220             break;
221         }
222         case Symbol::Kind::kField: {
223             const Field& f = s.as<Field>();
224             this->writeCommand(Rehydrator::kField_Command);
225             this->writeU16(this->symbolId(&f.owner()));
226             this->writeU8(f.fieldIndex());
227             break;
228         }
229         case Symbol::Kind::kExternal:
230             SkASSERT(false);
231             break;
232     }
233 }
234 
write(const SymbolTable & symbols)235 void Dehydrator::write(const SymbolTable& symbols) {
236     this->writeCommand(Rehydrator::kSymbolTable_Command);
237     this->writeU8(symbols.isBuiltin());
238     this->writeU16(symbols.fOwnedSymbols.size());
239 
240     // write owned symbols
241     for (const std::unique_ptr<const Symbol>& s : symbols.fOwnedSymbols) {
242         this->write(*s);
243     }
244 
245     // write symbols
246     this->writeU16(symbols.fSymbols.count());
247     std::map<std::string_view, const Symbol*> ordered;
248     symbols.foreach([&](std::string_view name, const Symbol* symbol) {
249         ordered.insert({name, symbol});
250     });
251     for (std::pair<std::string_view, const Symbol*> p : ordered) {
252         bool found = false;
253         for (size_t i = 0; i < symbols.fOwnedSymbols.size(); ++i) {
254             if (symbols.fOwnedSymbols[i].get() == p.second) {
255                 fCommandBreaks.add(fBody.bytesWritten());
256                 this->writeU16(i);
257                 found = true;
258                 break;
259             }
260         }
261         if (!found) {
262             // we should only fail to find builtin types
263             SkASSERT(p.second->is<Type>() && p.second->as<Type>().isInBuiltinTypes());
264             this->writeU16(Rehydrator::kBuiltin_Symbol);
265             this->write(p.second->name());
266         }
267     }
268 }
269 
270 
writeExpressionSpan(const SkSpan<const std::unique_ptr<Expression>> & span)271 void Dehydrator::writeExpressionSpan(const SkSpan<const std::unique_ptr<Expression>>& span) {
272     this->writeU8(span.size());
273     for (const auto& expr : span) {
274         this->write(expr.get());
275     }
276 }
277 
write(const Expression * e)278 void Dehydrator::write(const Expression* e) {
279     if (e) {
280         switch (e->kind()) {
281             case Expression::Kind::kBinary: {
282                 const BinaryExpression& b = e->as<BinaryExpression>();
283                 this->writeCommand(Rehydrator::kBinary_Command);
284                 this->write(b.left().get());
285                 this->writeU8((int) b.getOperator().kind());
286                 this->write(b.right().get());
287                 break;
288             }
289             case Expression::Kind::kChildCall:
290                 SkDEBUGFAIL("unimplemented--not expected to be used from within an include file");
291                 break;
292 
293             case Expression::Kind::kCodeString:
294                 SkDEBUGFAIL("shouldn't be able to receive kCodeString here");
295                 break;
296 
297             case Expression::Kind::kConstructorArray:
298                 this->writeCommand(Rehydrator::kConstructorArray_Command);
299                 this->write(e->type());
300                 this->writeExpressionSpan(e->as<ConstructorArray>().argumentSpan());
301                 break;
302 
303             case Expression::Kind::kConstructorArrayCast:
304                 this->writeCommand(Rehydrator::kConstructorArrayCast_Command);
305                 this->write(e->type());
306                 this->writeExpressionSpan(e->as<ConstructorArrayCast>().argumentSpan());
307                 break;
308 
309             case Expression::Kind::kConstructorCompound:
310                 this->writeCommand(Rehydrator::kConstructorCompound_Command);
311                 this->write(e->type());
312                 this->writeExpressionSpan(e->as<ConstructorCompound>().argumentSpan());
313                 break;
314 
315             case Expression::Kind::kConstructorCompoundCast:
316                 this->writeCommand(Rehydrator::kConstructorCompoundCast_Command);
317                 this->write(e->type());
318                 this->writeExpressionSpan(e->as<ConstructorCompoundCast>().argumentSpan());
319                 break;
320 
321             case Expression::Kind::kConstructorDiagonalMatrix:
322                 this->writeCommand(Rehydrator::kConstructorDiagonalMatrix_Command);
323                 this->write(e->type());
324                 this->writeExpressionSpan(e->as<ConstructorDiagonalMatrix>().argumentSpan());
325                 break;
326 
327             case Expression::Kind::kConstructorMatrixResize:
328                 this->writeCommand(Rehydrator::kConstructorMatrixResize_Command);
329                 this->write(e->type());
330                 this->writeExpressionSpan(e->as<ConstructorMatrixResize>().argumentSpan());
331                 break;
332 
333             case Expression::Kind::kConstructorScalarCast:
334                 this->writeCommand(Rehydrator::kConstructorScalarCast_Command);
335                 this->write(e->type());
336                 this->writeExpressionSpan(e->as<ConstructorScalarCast>().argumentSpan());
337                 break;
338 
339             case Expression::Kind::kConstructorSplat:
340                 this->writeCommand(Rehydrator::kConstructorSplat_Command);
341                 this->write(e->type());
342                 this->writeExpressionSpan(e->as<ConstructorSplat>().argumentSpan());
343                 break;
344 
345             case Expression::Kind::kConstructorStruct:
346                 this->writeCommand(Rehydrator::kConstructorStruct_Command);
347                 this->write(e->type());
348                 this->writeExpressionSpan(e->as<ConstructorStruct>().argumentSpan());
349                 break;
350 
351             case Expression::Kind::kExternalFunctionCall:
352             case Expression::Kind::kExternalFunctionReference:
353                 SkDEBUGFAIL("unimplemented--not expected to be used from within an include file");
354                 break;
355 
356             case Expression::Kind::kFieldAccess: {
357                 const FieldAccess& f = e->as<FieldAccess>();
358                 this->writeCommand(Rehydrator::kFieldAccess_Command);
359                 this->write(f.base().get());
360                 this->writeU8(f.fieldIndex());
361                 this->writeU8((int8_t) f.ownerKind());
362                 break;
363             }
364             case Expression::Kind::kFunctionCall: {
365                 const FunctionCall& f = e->as<FunctionCall>();
366                 this->writeCommand(Rehydrator::kFunctionCall_Command);
367                 this->write(f.type());
368                 this->writeId(&f.function());
369                 this->writeU8(f.arguments().size());
370                 for (const auto& a : f.arguments()) {
371                     this->write(a.get());
372                 }
373                 break;
374             }
375             case Expression::Kind::kIndex: {
376                 const IndexExpression& i = e->as<IndexExpression>();
377                 this->writeCommand(Rehydrator::kIndex_Command);
378                 this->write(i.base().get());
379                 this->write(i.index().get());
380                 break;
381             }
382             case Expression::Kind::kLiteral: {
383                 const Literal& l = e->as<Literal>();
384                 if (l.type().isFloat()) {
385                     float value = l.floatValue();
386                     int32_t floatBits;
387                     memcpy(&floatBits, &value, sizeof(floatBits));
388                     this->writeCommand(Rehydrator::kFloatLiteral_Command);
389                     this->write(l.type());
390                     this->writeS32(floatBits);
391                 } else if (l.type().isBoolean()) {
392                     this->writeCommand(Rehydrator::kBoolLiteral_Command);
393                     this->writeU8(l.boolValue());
394                 } else {
395                     SkASSERT(l.type().isInteger());
396                     this->writeCommand(Rehydrator::kIntLiteral_Command);
397                     this->write(l.type());
398                     if (l.type().isUnsigned()) {
399                         this->writeU32(l.intValue());
400                     } else {
401                         this->writeS32(l.intValue());
402                     }
403                 }
404                 break;
405             }
406             case Expression::Kind::kPostfix: {
407                 const PostfixExpression& p = e->as<PostfixExpression>();
408                 this->writeCommand(Rehydrator::kPostfix_Command);
409                 this->writeU8((int) p.getOperator().kind());
410                 this->write(p.operand().get());
411                 break;
412             }
413             case Expression::Kind::kPrefix: {
414                 const PrefixExpression& p = e->as<PrefixExpression>();
415                 this->writeCommand(Rehydrator::kPrefix_Command);
416                 this->writeU8((int) p.getOperator().kind());
417                 this->write(p.operand().get());
418                 break;
419             }
420             case Expression::Kind::kSetting: {
421                 const Setting& s = e->as<Setting>();
422                 this->writeCommand(Rehydrator::kSetting_Command);
423                 this->write(s.name());
424                 break;
425             }
426             case Expression::Kind::kSwizzle: {
427                 const Swizzle& s = e->as<Swizzle>();
428                 this->writeCommand(Rehydrator::kSwizzle_Command);
429                 this->write(s.base().get());
430                 this->writeU8(s.components().size());
431                 for (int c : s.components()) {
432                     this->writeU8(c);
433                 }
434                 break;
435             }
436             case Expression::Kind::kTernary: {
437                 const TernaryExpression& t = e->as<TernaryExpression>();
438                 this->writeCommand(Rehydrator::kTernary_Command);
439                 this->write(t.test().get());
440                 this->write(t.ifTrue().get());
441                 this->write(t.ifFalse().get());
442                 break;
443             }
444             case Expression::Kind::kVariableReference: {
445                 const VariableReference& v = e->as<VariableReference>();
446                 this->writeCommand(Rehydrator::kVariableReference_Command);
447                 this->writeId(v.variable());
448                 this->writeU8((int8_t) v.refKind());
449                 break;
450             }
451             case Expression::Kind::kFunctionReference:
452             case Expression::Kind::kMethodReference:
453             case Expression::Kind::kPoison:
454             case Expression::Kind::kTypeReference:
455                 SkDEBUGFAIL("this expression shouldn't appear in finished code");
456                 break;
457         }
458     } else {
459         this->writeCommand(Rehydrator::kVoid_Command);
460     }
461 }
462 
write(const Statement * s)463 void Dehydrator::write(const Statement* s) {
464     if (s) {
465         switch (s->kind()) {
466             case Statement::Kind::kBlock: {
467                 const Block& b = s->as<Block>();
468                 this->writeCommand(Rehydrator::kBlock_Command);
469                 AutoDehydratorSymbolTable symbols(this, b.symbolTable());
470                 this->writeU8(b.children().size());
471                 for (const std::unique_ptr<Statement>& blockStmt : b.children()) {
472                     this->write(blockStmt.get());
473                 }
474                 this->writeU8(b.isScope());
475                 break;
476             }
477             case Statement::Kind::kBreak:
478                 this->writeCommand(Rehydrator::kBreak_Command);
479                 break;
480             case Statement::Kind::kContinue:
481                 this->writeCommand(Rehydrator::kContinue_Command);
482                 break;
483             case Statement::Kind::kDiscard:
484                 this->writeCommand(Rehydrator::kDiscard_Command);
485                 break;
486             case Statement::Kind::kDo: {
487                 const DoStatement& d = s->as<DoStatement>();
488                 this->writeCommand(Rehydrator::kDo_Command);
489                 this->write(d.statement().get());
490                 this->write(d.test().get());
491                 break;
492             }
493             case Statement::Kind::kExpression: {
494                 const ExpressionStatement& e = s->as<ExpressionStatement>();
495                 this->writeCommand(Rehydrator::kExpressionStatement_Command);
496                 this->write(e.expression().get());
497                 break;
498             }
499             case Statement::Kind::kFor: {
500                 const ForStatement& f = s->as<ForStatement>();
501                 this->writeCommand(Rehydrator::kFor_Command);
502                 AutoDehydratorSymbolTable symbols(this, f.symbols());
503                 this->write(f.initializer().get());
504                 this->write(f.test().get());
505                 this->write(f.next().get());
506                 this->write(f.statement().get());
507                 break;
508             }
509             case Statement::Kind::kIf: {
510                 const IfStatement& i = s->as<IfStatement>();
511                 this->writeCommand(Rehydrator::kIf_Command);
512                 this->writeU8(i.isStatic());
513                 this->write(i.test().get());
514                 this->write(i.ifTrue().get());
515                 this->write(i.ifFalse().get());
516                 break;
517             }
518             case Statement::Kind::kInlineMarker: {
519                 const InlineMarker& i = s->as<InlineMarker>();
520                 this->writeCommand(Rehydrator::kInlineMarker_Command);
521                 this->writeId(&i.function());
522                 break;
523             }
524             case Statement::Kind::kNop:
525                 this->writeCommand(Rehydrator::kNop_Command);
526                 break;
527             case Statement::Kind::kReturn: {
528                 const ReturnStatement& r = s->as<ReturnStatement>();
529                 this->writeCommand(Rehydrator::kReturn_Command);
530                 this->write(r.expression().get());
531                 break;
532             }
533             case Statement::Kind::kSwitch: {
534                 const SwitchStatement& ss = s->as<SwitchStatement>();
535                 this->writeCommand(Rehydrator::kSwitch_Command);
536                 this->writeU8(ss.isStatic());
537                 AutoDehydratorSymbolTable symbols(this, ss.symbols());
538                 this->write(ss.value().get());
539                 this->writeU8(ss.cases().size());
540                 for (const std::unique_ptr<Statement>& stmt : ss.cases()) {
541                     const SwitchCase& sc = stmt->as<SwitchCase>();
542                     if (sc.isDefault()) {
543                         this->writeU8(1);
544                     } else {
545                         this->writeU8(0);
546                         this->writeS32(sc.value());
547                     }
548                     this->write(sc.statement().get());
549                 }
550                 break;
551             }
552             case Statement::Kind::kSwitchCase:
553                 SkDEBUGFAIL("SwitchCase statements shouldn't appear here");
554                 break;
555             case Statement::Kind::kVarDeclaration: {
556                 const VarDeclaration& v = s->as<VarDeclaration>();
557                 this->writeCommand(Rehydrator::kVarDeclaration_Command);
558                 this->writeU16(this->symbolId(&v.var()));
559                 this->write(v.baseType());
560                 this->writeU8(v.arraySize());
561                 this->write(v.value().get());
562                 break;
563             }
564         }
565     } else {
566         this->writeCommand(Rehydrator::kVoid_Command);
567     }
568 }
569 
write(const ProgramElement & e)570 void Dehydrator::write(const ProgramElement& e) {
571     switch (e.kind()) {
572         case ProgramElement::Kind::kExtension:
573             SkASSERT(false);
574             break;
575         case ProgramElement::Kind::kFunction: {
576             const FunctionDefinition& f = e.as<FunctionDefinition>();
577             this->writeCommand(Rehydrator::kFunctionDefinition_Command);
578             this->writeU16(this->symbolId(&f.declaration()));
579             this->write(f.body().get());
580             break;
581         }
582         case ProgramElement::Kind::kFunctionPrototype: {
583             const FunctionPrototype& f = e.as<FunctionPrototype>();
584             if (!f.isBuiltin()) {
585                 this->writeCommand(Rehydrator::kFunctionPrototype_Command);
586                 this->writeU16(this->symbolId(&f.declaration()));
587             }
588             break;
589         }
590         case ProgramElement::Kind::kInterfaceBlock: {
591             const InterfaceBlock& i = e.as<InterfaceBlock>();
592             this->writeCommand(Rehydrator::kInterfaceBlock_Command);
593             this->write(i.variable());
594             this->write(i.typeName());
595             this->write(i.instanceName());
596             this->writeU8(i.arraySize());
597             break;
598         }
599         case ProgramElement::Kind::kModifiers:
600             SkASSERT(false);
601             break;
602         case ProgramElement::Kind::kStructDefinition: {
603             const StructDefinition& structDef = e.as<StructDefinition>();
604             this->writeCommand(Rehydrator::kStructDefinition_Command);
605             this->write(structDef.type());
606             break;
607         }
608         case ProgramElement::Kind::kGlobalVar: {
609             const GlobalVarDeclaration& v = e.as<GlobalVarDeclaration>();
610             this->writeCommand(Rehydrator::kGlobalVar_Command);
611             this->write(v.declaration().get());
612             break;
613         }
614     }
615 }
616 
write(const std::vector<std::unique_ptr<ProgramElement>> & elements)617 void Dehydrator::write(const std::vector<std::unique_ptr<ProgramElement>>& elements) {
618     this->writeCommand(Rehydrator::kElements_Command);
619     for (const auto& e : elements) {
620         this->write(*e);
621     }
622     this->writeCommand(Rehydrator::kElementsComplete_Command);
623 }
624 
write(const Program & program)625 void Dehydrator::write(const Program& program) {
626     this->writeCommand(Rehydrator::kProgram_Command);
627     this->writeU8((int)program.fConfig->fKind);
628     this->write(*program.fSymbols);
629 
630     // Write the elements
631     this->writeCommand(Rehydrator::kElements_Command);
632     for (const auto& e : program.fSharedElements) {
633         this->writeCommand(Rehydrator::kSharedFunction_Command);
634         const FunctionDefinition& f = e->as<FunctionDefinition>();
635         const FunctionDeclaration& decl = f.declaration();
636         this->writeU8(decl.parameters().size());
637         for (const Variable* param : decl.parameters()) {
638             this->write(*param);
639         }
640         this->write(f.declaration());
641         this->write(*e);
642     }
643     for (const auto& e : program.fOwnedElements) {
644         this->write(*e);
645     }
646     this->writeCommand(Rehydrator::kElementsComplete_Command);
647 
648     // Write the inputs
649     struct KnownSkSLProgramInputs { bool useRTFlipUniform; };
650     // Since it would be easy to forget to update this code in the face of Inputs changes and any
651     // resulting bugs could be very subtle, assert that the struct hasn't changed:
652     static_assert(sizeof(SkSL::Program::Inputs) == sizeof(KnownSkSLProgramInputs));
653     this->writeU8(program.fInputs.fUseFlipRTUniform);
654 }
655 
finish(OutputStream & out)656 void Dehydrator::finish(OutputStream& out) {
657     out.write16(Rehydrator::kVersion);
658     std::string stringBuffer = fStringBuffer.str();
659     std::string commandBuffer = fBody.str();
660     out.write16(fStringBuffer.str().size());
661     fStringBufferStart = 4;
662     out.writeString(stringBuffer);
663     fCommandStart = fStringBufferStart + stringBuffer.size();
664     out.writeString(commandBuffer);
665 }
666 
prefixAtOffset(size_t byte)667 const char* Dehydrator::prefixAtOffset(size_t byte) {
668     if (byte >= fCommandStart) {
669         return fCommandBreaks.contains(byte - fCommandStart) ? "\n" : "";
670     }
671     if (byte >= fStringBufferStart) {
672         return fStringBreaks.contains(byte - fStringBufferStart) ? "\n" : "";
673     }
674     return "";
675 }
676 
677 } // namespace SkSL
678