6ae9346cd3
This introduces two new instructions: Jump and JumpIfFalse. Jumps are made to a Bytecode::Label, which is a simple object that represents a location in the bytecode stream. Note that you may not always know the target of a jump when adding the jump instruction itself, but we can just update the instruction later on during codegen once we know where the jump target is. The Bytecode::Interpreter now implements jumping via a jump slot that gets checked after each instruction to see if a jump is pending. If not, we just increment the PC as usual.
38 lines
810 B
C++
38 lines
810 B
C++
/*
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* Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
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*
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* SPDX-License-Identifier: BSD-2-Clause
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*/
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#pragma once
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#include <LibJS/Bytecode/Label.h>
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#include <LibJS/Bytecode/Register.h>
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#include <LibJS/Forward.h>
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#include <LibJS/Heap/Cell.h>
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#include <LibJS/Runtime/Value.h>
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namespace JS::Bytecode {
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class Interpreter {
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public:
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explicit Interpreter(GlobalObject&);
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~Interpreter();
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GlobalObject& global_object() { return m_global_object; }
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VM& vm() { return m_vm; }
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void run(Bytecode::Block const&);
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Value& reg(Register const& r) { return m_registers[r.index()]; }
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void jump(Label const& label) { m_pending_jump = label.address(); }
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private:
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VM& m_vm;
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GlobalObject& m_global_object;
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Vector<Value> m_registers;
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Optional<size_t> m_pending_jump;
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};
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}
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