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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef vm_BindingKind_h
#define vm_BindingKind_h
#include "mozilla/Assertions.h" // MOZ_ASSERT, MOZ_ASSERT_IF
#include "mozilla/Casting.h" // mozilla::AssertedCast
#include <stdint.h> // uint16_t, uint32_t
#include "vm/BytecodeUtil.h" // LOCALNO_LIMIT, ENVCOORD_SLOT_LIMIT
namespace js {
enum class BindingKind : uint8_t {
Import,
FormalParameter,
Var,
Let,
Const,
// So you think named lambda callee names are consts? Nope! They don't
// throw when being assigned to in sloppy mode.
NamedLambdaCallee
};
static inline bool BindingKindIsLexical(BindingKind kind) {
return kind == BindingKind::Let || kind == BindingKind::Const;
}
class BindingLocation {
public:
enum class Kind {
Global,
Argument,
Frame,
Environment,
Import,
NamedLambdaCallee
};
private:
Kind kind_;
uint32_t slot_;
BindingLocation(Kind kind, uint32_t slot) : kind_(kind), slot_(slot) {}
public:
static BindingLocation Global() {
return BindingLocation(Kind::Global, UINT32_MAX);
}
static BindingLocation Argument(uint16_t slot) {
return BindingLocation(Kind::Argument, slot);
}
static BindingLocation Frame(uint32_t slot) {
MOZ_ASSERT(slot < LOCALNO_LIMIT);
return BindingLocation(Kind::Frame, slot);
}
static BindingLocation Environment(uint32_t slot) {
MOZ_ASSERT(slot < ENVCOORD_SLOT_LIMIT);
return BindingLocation(Kind::Environment, slot);
}
static BindingLocation Import() {
return BindingLocation(Kind::Import, UINT32_MAX);
}
static BindingLocation NamedLambdaCallee() {
return BindingLocation(Kind::NamedLambdaCallee, UINT32_MAX);
}
bool operator==(const BindingLocation& other) const {
return kind_ == other.kind_ && slot_ == other.slot_;
}
bool operator!=(const BindingLocation& other) const {
return !operator==(other);
}
Kind kind() const { return kind_; }
uint32_t slot() const {
MOZ_ASSERT(kind_ == Kind::Frame || kind_ == Kind::Environment);
return slot_;
}
uint16_t argumentSlot() const {
MOZ_ASSERT(kind_ == Kind::Argument);
return mozilla::AssertedCast<uint16_t>(slot_);
}
};
} // namespace js
#endif // vm_BindingKind_h