69dddd4ef5
This patch begins the work of implementing JavaScript execution in a bytecode VM instead of an AST tree-walk interpreter. It's probably quite naive, but we have to start somewhere. The basic idea is that you call Bytecode::Generator::generate() on an AST node and it hands you back a Bytecode::Block filled with instructions that can then be interpreted by a Bytecode::Interpreter. This first version only implements two instructions: Load and Add. :^) Each bytecode block has infinity registers, and the interpreter resizes its register file to fit the block being executed. Two new `js` options are added in this patch as well: `-d` will dump the generated bytecode `-b` will execute the generated bytecode Note that unless `-d` and/or `-b` are specified, none of the bytecode related stuff in LibJS runs at all. This is implemented in parallel with the existing AST interpreter. :^)
37 lines
662 B
C++
37 lines
662 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 <AK/OwnPtr.h>
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#include <LibJS/Forward.h>
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namespace JS::Bytecode {
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class Generator {
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public:
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static OwnPtr<Block> generate(ASTNode const&);
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Register allocate_register();
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template<typename OpType, typename... Args>
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void emit(Args&&... args)
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{
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auto instruction = make<OpType>(forward<Args>(args)...);
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append(move(instruction));
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}
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private:
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Generator();
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~Generator();
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void append(NonnullOwnPtr<Instruction>);
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OwnPtr<Block> m_block;
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u32 m_next_register { 1 };
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};
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}
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