blob: 405a5d1f55b8637c84a2073baa8099b9b3c241ad (
plain)
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
|
/*
* Copyright 2016 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SKSL_VARIABLEREFERENCE
#define SKSL_VARIABLEREFERENCE
#include "SkSLExpression.h"
namespace SkSL {
class IRGenerator;
/**
* A reference to a variable, through which it can be read or written. In the statement:
*
* x = x + 1;
*
* there is only one Variable 'x', but two VariableReferences to it.
*/
struct VariableReference : public Expression {
enum RefKind {
kRead_RefKind,
kWrite_RefKind,
kReadWrite_RefKind,
// taking the address of a variable - we consider this a read & write but don't complain if
// the variable was not previously assigned
kPointer_RefKind
};
VariableReference(int offset, const Variable& variable, RefKind refKind = kRead_RefKind);
~VariableReference() override;
RefKind refKind() const {
return fRefKind;
}
void setRefKind(RefKind refKind);
bool hasSideEffects() const override {
return false;
}
bool isConstant() const override {
return 0 != (fVariable.fModifiers.fFlags & Modifiers::kConst_Flag);
}
std::unique_ptr<Expression> clone() const override {
return std::unique_ptr<Expression>(new VariableReference(fOffset, fVariable, fRefKind));
}
String description() const override {
return fVariable.fName;
}
static std::unique_ptr<Expression> copy_constant(const IRGenerator& irGenerator,
const Expression* expr);
std::unique_ptr<Expression> constantPropagate(const IRGenerator& irGenerator,
const DefinitionMap& definitions) override;
const Variable& fVariable;
RefKind fRefKind;
private:
typedef Expression INHERITED;
};
} // namespace
#endif
|
