1/*
2 * Copyright (C) 2013-2018 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 "CodeBlock.h"
29#include "Register.h"
30#include "StackAlignment.h"
31#include <wtf/ForbidHeapAllocation.h>
32
33namespace JSC {
34
35struct JS_EXPORT_PRIVATE ProtoCallFrame {
36 WTF_FORBID_HEAP_ALLOCATION;
37public:
38 // CodeBlock, Callee, ArgumentCount, and |this|.
39 static constexpr unsigned numberOfRegisters { 4 };
40
41 Register codeBlockValue;
42 Register calleeValue;
43 Register argCountAndCodeOriginValue;
44 Register thisArg;
45 uint32_t paddedArgCount;
46 bool hasArityMismatch;
47 JSValue *args;
48
49 void init(CodeBlock*, JSObject*, JSValue, int, JSValue* otherArgs = 0);
50
51 CodeBlock* codeBlock() const { return codeBlockValue.Register::codeBlock(); }
52 void setCodeBlock(CodeBlock* codeBlock) { codeBlockValue = codeBlock; }
53
54 JSObject* callee() const { return calleeValue.Register::object(); }
55 void setCallee(JSObject* callee) { calleeValue = callee; }
56
57 int argumentCountIncludingThis() const { return argCountAndCodeOriginValue.payload(); }
58 int argumentCount() const { return argumentCountIncludingThis() - 1; }
59 void setArgumentCountIncludingThis(int count) { argCountAndCodeOriginValue.payload() = count; }
60 void setPaddedArgCount(uint32_t argCount) { paddedArgCount = argCount; }
61
62 void clearCurrentVPC() { argCountAndCodeOriginValue.tag() = 0; }
63
64 JSValue thisValue() const { return thisArg.Register::jsValue(); }
65 void setThisValue(JSValue value) { thisArg = value; }
66
67 bool needArityCheck() { return hasArityMismatch; }
68
69 JSValue argument(size_t argumentIndex)
70 {
71 ASSERT(static_cast<int>(argumentIndex) < argumentCount());
72 return args[argumentIndex];
73 }
74 void setArgument(size_t argumentIndex, JSValue value)
75 {
76 ASSERT(static_cast<int>(argumentIndex) < argumentCount());
77 args[argumentIndex] = value;
78 }
79};
80
81inline void ProtoCallFrame::init(CodeBlock* codeBlock, JSObject* callee, JSValue thisValue, int argCountIncludingThis, JSValue* otherArgs)
82{
83 this->args = otherArgs;
84 this->setCodeBlock(codeBlock);
85 this->setCallee(callee);
86 this->setArgumentCountIncludingThis(argCountIncludingThis);
87 if (codeBlock && argCountIncludingThis < codeBlock->numParameters())
88 this->hasArityMismatch = true;
89 else
90 this->hasArityMismatch = false;
91
92 // Round up argCountIncludingThis to keep the stack frame size aligned.
93 size_t paddedArgsCount = roundArgumentCountToAlignFrame(argCountIncludingThis);
94 this->setPaddedArgCount(paddedArgsCount);
95 this->clearCurrentVPC();
96 this->setThisValue(thisValue);
97}
98
99} // namespace JSC
100