1/*
2 * Copyright (C) 2019 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28#include "InstructionStream.h"
29#include <wtf/SegmentedVector.h>
30
31namespace JSC {
32
33class RegisterID;
34
35template<typename BytecodeGenerator>
36class GenericBoundLabel;
37
38template<typename BytecodeGenerator>
39class GenericLabel;
40
41template<typename Traits>
42class BytecodeGeneratorBase {
43 template<typename BytecodeGenerator>
44 friend class GenericBoundLabel;
45
46 template<typename BytecodeGenerator>
47 friend class GenericLabel;
48
49public:
50 BytecodeGeneratorBase(typename Traits::CodeBlock, uint32_t virtualRegisterCountForCalleeSaves);
51
52 void allocateCalleeSaveSpace(uint32_t virtualRegisterCountForCalleeSaves);
53
54 Ref<GenericLabel<Traits>> newLabel();
55 Ref<GenericLabel<Traits>> newEmittedLabel();
56 RegisterID* newRegister();
57 RegisterID* addVar();
58
59 // Returns the next available temporary register. Registers returned by
60 // newTemporary require a modified form of reference counting: any
61 // register with a refcount of 0 is considered "available", meaning that
62 // the next instruction may overwrite it.
63 RegisterID* newTemporary();
64
65 void emitLabel(GenericLabel<Traits>&);
66 void recordOpcode(typename Traits::OpcodeID);
67 void alignWideOpcode16();
68 void alignWideOpcode32();
69
70 void write(uint8_t);
71 void write(uint16_t);
72 void write(uint32_t);
73 void write(int8_t);
74 void write(int16_t);
75 void write(int32_t);
76
77protected:
78 void reclaimFreeRegisters();
79
80 InstructionStreamWriter m_writer;
81 typename Traits::CodeBlock m_codeBlock;
82
83 typename Traits::OpcodeID m_lastOpcodeID = Traits::opcodeForDisablingOptimizations;
84 InstructionStream::MutableRef m_lastInstruction { m_writer.ref() };
85
86 SegmentedVector<GenericLabel<Traits>, 32> m_labels;
87 SegmentedVector<RegisterID, 32> m_calleeLocals;
88};
89
90} // namespace JSC
91