xref: /aosp_15_r20/external/skia/src/sksl/ir/SkSLFieldAccess.h (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 /*
2  * Copyright 2016 Google Inc.
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 #ifndef SKSL_FIELDACCESS
9 #define SKSL_FIELDACCESS
10 
11 #include "include/core/SkSpan.h"
12 #include "src/sksl/SkSLPosition.h"
13 #include "src/sksl/ir/SkSLExpression.h"
14 #include "src/sksl/ir/SkSLIRNode.h"
15 #include "src/sksl/ir/SkSLType.h"
16 
17 #include <cstddef>
18 #include <cstdint>
19 #include <memory>
20 #include <string>
21 #include <string_view>
22 #include <utility>
23 
24 namespace SkSL {
25 
26 class Context;
27 enum class OperatorPrecedence : uint8_t;
28 
29 enum class FieldAccessOwnerKind : int8_t {
30     kDefault,
31     // this field access is to a field of an anonymous interface block (and thus, the field name
32     // is actually in global scope, so only the field name needs to be written in GLSL)
33     kAnonymousInterfaceBlock
34 };
35 
36 /**
37  * An expression which extracts a field from a struct, as in 'foo.bar'.
38  */
39 class FieldAccess final : public Expression {
40 public:
41     using OwnerKind = FieldAccessOwnerKind;
42 
43     inline static constexpr Kind kIRNodeKind = Kind::kFieldAccess;
44 
45     FieldAccess(Position pos, std::unique_ptr<Expression> base, int fieldIndex,
46                 OwnerKind ownerKind = OwnerKind::kDefault)
47     : INHERITED(pos, kIRNodeKind, base->type().fields()[fieldIndex].fType)
48     , fFieldIndex(fieldIndex)
49     , fOwnerKind(ownerKind)
50     , fBase(std::move(base)) {}
51 
52     // Returns a field-access expression; reports errors via the ErrorReporter.
53     static std::unique_ptr<Expression> Convert(const Context& context,
54                                                Position pos,
55                                                std::unique_ptr<Expression> base,
56                                                std::string_view field);
57 
58     // Returns a field-access expression; reports errors via ASSERT.
59     static std::unique_ptr<Expression> Make(const Context& context,
60                                             Position pos,
61                                             std::unique_ptr<Expression> base,
62                                             int fieldIndex,
63                                             OwnerKind ownerKind = OwnerKind::kDefault);
64 
base()65     std::unique_ptr<Expression>& base() {
66         return fBase;
67     }
68 
base()69     const std::unique_ptr<Expression>& base() const {
70         return fBase;
71     }
72 
fieldIndex()73     int fieldIndex() const {
74         return fFieldIndex;
75     }
76 
ownerKind()77     OwnerKind ownerKind() const {
78         return fOwnerKind;
79     }
80 
clone(Position pos)81     std::unique_ptr<Expression> clone(Position pos) const override {
82         return std::make_unique<FieldAccess>(pos,
83                                              this->base()->clone(),
84                                              this->fieldIndex(),
85                                              this->ownerKind());
86     }
87 
88     size_t initialSlot() const;
89 
90     std::string description(OperatorPrecedence) const override;
91 
92 private:
93     int fFieldIndex;
94     FieldAccessOwnerKind fOwnerKind;
95     std::unique_ptr<Expression> fBase;
96 
97     using INHERITED = Expression;
98 };
99 
100 }  // namespace SkSL
101 
102 #endif
103