| 1 | /*
|
|---|
| 2 | * Copyright (C) 2008 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 | *
|
|---|
| 8 | * 1. Redistributions of source code must retain the above copyright
|
|---|
| 9 | * notice, this list of conditions and the following disclaimer.
|
|---|
| 10 | * 2. Redistributions in binary form must reproduce the above copyright
|
|---|
| 11 | * notice, this list of conditions and the following disclaimer in the
|
|---|
| 12 | * documentation and/or other materials provided with the distribution.
|
|---|
| 13 | * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
|
|---|
| 14 | * its contributors may be used to endorse or promote products derived
|
|---|
| 15 | * from this software without specific prior written permission.
|
|---|
| 16 | *
|
|---|
| 17 | * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
|
|---|
| 18 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|---|
| 19 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|---|
| 20 | * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
|
|---|
| 21 | * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|---|
| 22 | * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
|
|---|
| 23 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
|---|
| 24 | * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|---|
| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
|---|
| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|---|
| 27 | */
|
|---|
| 28 |
|
|---|
| 29 | #ifndef LabelID_h
|
|---|
| 30 | #define LabelID_h
|
|---|
| 31 |
|
|---|
| 32 | #include "CodeBlock.h"
|
|---|
| 33 | #include "Instruction.h"
|
|---|
| 34 | #include <wtf/Assertions.h>
|
|---|
| 35 | #include <wtf/Vector.h>
|
|---|
| 36 | #include <limits.h>
|
|---|
| 37 |
|
|---|
| 38 | namespace JSC {
|
|---|
| 39 |
|
|---|
| 40 | class LabelID {
|
|---|
| 41 | public:
|
|---|
| 42 | explicit LabelID(CodeBlock* codeBlock)
|
|---|
| 43 | : m_refCount(0)
|
|---|
| 44 | , m_location(invalidLocation)
|
|---|
| 45 | , m_codeBlock(codeBlock)
|
|---|
| 46 | {
|
|---|
| 47 | }
|
|---|
| 48 |
|
|---|
| 49 | void setLocation(unsigned location)
|
|---|
| 50 | {
|
|---|
| 51 | m_location = location;
|
|---|
| 52 |
|
|---|
| 53 | unsigned size = m_unresolvedJumps.size();
|
|---|
| 54 | for (unsigned i = 0; i < size; ++i) {
|
|---|
| 55 | unsigned j = m_unresolvedJumps[i];
|
|---|
| 56 | m_codeBlock->instructions[j].u.operand = m_location - j;
|
|---|
| 57 | }
|
|---|
| 58 |
|
|---|
| 59 | m_codeBlock->labels.add(location);
|
|---|
| 60 | }
|
|---|
| 61 |
|
|---|
| 62 | int offsetFrom(int location) const
|
|---|
| 63 | {
|
|---|
| 64 | if (m_location == invalidLocation) {
|
|---|
| 65 | m_unresolvedJumps.append(location);
|
|---|
| 66 | return 0;
|
|---|
| 67 | }
|
|---|
| 68 | return m_location - location;
|
|---|
| 69 | }
|
|---|
| 70 |
|
|---|
| 71 | void ref() { ++m_refCount; }
|
|---|
| 72 | void deref()
|
|---|
| 73 | {
|
|---|
| 74 | --m_refCount;
|
|---|
| 75 | ASSERT(m_refCount >= 0);
|
|---|
| 76 | }
|
|---|
| 77 | int refCount() const { return m_refCount; }
|
|---|
| 78 |
|
|---|
| 79 | bool isForwardLabel() const { return m_location == invalidLocation; }
|
|---|
| 80 |
|
|---|
| 81 | private:
|
|---|
| 82 | typedef Vector<int, 8> JumpVector;
|
|---|
| 83 |
|
|---|
| 84 | static const unsigned invalidLocation = UINT_MAX;
|
|---|
| 85 |
|
|---|
| 86 | int m_refCount;
|
|---|
| 87 | unsigned m_location;
|
|---|
| 88 | CodeBlock* m_codeBlock;
|
|---|
| 89 | mutable JumpVector m_unresolvedJumps;
|
|---|
| 90 | };
|
|---|
| 91 |
|
|---|
| 92 | } // namespace JSC
|
|---|
| 93 |
|
|---|
| 94 | #endif // LabelID_h
|
|---|
