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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 frontend_DoWhileEmitter_h
#define frontend_DoWhileEmitter_h
#include "mozilla/Attributes.h"
#include "mozilla/Maybe.h"
#include <stdint.h>
#include "frontend/BytecodeControlStructures.h"
namespace js {
namespace frontend {
struct BytecodeEmitter;
// Class for emitting bytecode for do-while loop.
//
// Usage: (check for the return value is omitted for simplicity)
//
// `do body while (cond);`
// DoWhileEmitter doWhile(this);
// doWhile.emitBody(offset_of_do, offset_of_body);
// emit(body);
// doWhile.emitCond();
// emit(cond);
// doWhile.emitEnd();
//
class MOZ_STACK_CLASS DoWhileEmitter {
BytecodeEmitter* bce_;
mozilla::Maybe<LoopControl> loopInfo_;
#ifdef DEBUG
// The state of this emitter.
//
// +-------+ emitBody +------+ emitCond +------+ emitEnd +-----+
// | Start |--------->| Body |--------->| Cond |--------->| End |
// +-------+ +------+ +------+ +-----+
enum class State {
// The initial state.
Start,
// After calling emitBody.
Body,
// After calling emitCond.
Cond,
// After calling emitEnd.
End
};
State state_ = State::Start;
#endif
public:
explicit DoWhileEmitter(BytecodeEmitter* bce);
// Parameters are the offset in the source code for each character below:
//
// do { ... } while ( x < 20 );
// ^ ^
// | |
// | bodyPos
// |
// doPos
[[nodiscard]] bool emitBody(uint32_t doPos, uint32_t bodyPos);
[[nodiscard]] bool emitCond();
[[nodiscard]] bool emitEnd();
};
} /* namespace frontend */
} /* namespace js */
#endif /* frontend_DoWhileEmitter_h */
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