1 /*
2 * Copyright 2021 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/ir/SkSLTernaryExpression.h"
9
10 #include "include/sksl/SkSLErrorReporter.h"
11 #include "src/sksl/SkSLConstantFolder.h"
12 #include "src/sksl/SkSLContext.h"
13 #include "src/sksl/SkSLOperators.h"
14 #include "src/sksl/SkSLProgramSettings.h"
15 #include "src/sksl/ir/SkSLLiteral.h"
16
17 namespace SkSL {
18
Convert(const Context & context,std::unique_ptr<Expression> test,std::unique_ptr<Expression> ifTrue,std::unique_ptr<Expression> ifFalse)19 std::unique_ptr<Expression> TernaryExpression::Convert(const Context& context,
20 std::unique_ptr<Expression> test,
21 std::unique_ptr<Expression> ifTrue,
22 std::unique_ptr<Expression> ifFalse) {
23 test = context.fTypes.fBool->coerceExpression(std::move(test), context);
24 if (!test || !ifTrue || !ifFalse) {
25 return nullptr;
26 }
27 int line = test->fLine;
28 const Type* trueType;
29 const Type* falseType;
30 const Type* resultType;
31 Operator equalityOp(Token::Kind::TK_EQEQ);
32 if (!equalityOp.determineBinaryType(context, ifTrue->type(), ifFalse->type(),
33 &trueType, &falseType, &resultType) ||
34 (*trueType != *falseType)) {
35 context.fErrors->error(line, "ternary operator result mismatch: '" +
36 ifTrue->type().displayName() + "', '" +
37 ifFalse->type().displayName() + "'");
38 return nullptr;
39 }
40 if (trueType->componentType().isOpaque()) {
41 context.fErrors->error(line, "ternary expression of opaque type '" +
42 trueType->displayName() + "' not allowed");
43 return nullptr;
44 }
45 if (context.fConfig->strictES2Mode() && trueType->isOrContainsArray()) {
46 context.fErrors->error(line, "ternary operator result may not be an array (or struct "
47 "containing an array)");
48 return nullptr;
49 }
50 ifTrue = trueType->coerceExpression(std::move(ifTrue), context);
51 if (!ifTrue) {
52 return nullptr;
53 }
54 ifFalse = falseType->coerceExpression(std::move(ifFalse), context);
55 if (!ifFalse) {
56 return nullptr;
57 }
58 return TernaryExpression::Make(context, std::move(test), std::move(ifTrue), std::move(ifFalse));
59 }
60
Make(const Context & context,std::unique_ptr<Expression> test,std::unique_ptr<Expression> ifTrue,std::unique_ptr<Expression> ifFalse)61 std::unique_ptr<Expression> TernaryExpression::Make(const Context& context,
62 std::unique_ptr<Expression> test,
63 std::unique_ptr<Expression> ifTrue,
64 std::unique_ptr<Expression> ifFalse) {
65 SkASSERT(ifTrue->type() == ifFalse->type());
66 SkASSERT(!ifTrue->type().componentType().isOpaque());
67 SkASSERT(!context.fConfig->strictES2Mode() || !ifTrue->type().isOrContainsArray());
68
69 const Expression* testExpr = ConstantFolder::GetConstantValueForVariable(*test);
70 if (testExpr->isBoolLiteral()) {
71 // static boolean test, just return one of the branches
72 return testExpr->as<Literal>().boolValue() ? std::move(ifTrue)
73 : std::move(ifFalse);
74 }
75
76 return std::make_unique<TernaryExpression>(test->fLine, std::move(test), std::move(ifTrue),
77 std::move(ifFalse));
78 }
79
80 } // namespace SkSL
81