interpreter/CallFrame.cpp

   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  * 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 #include "config.h"
  27 #include "CallFrame.h"
  28
  29 #include "CodeBlock.h"
  30 #include "Interpreter.h"
  31
  32 namespace JSC {
  33
  34 #ifndef NDEBUG
  35 void CallFrame::dumpCaller()
  36 {
  37     int signedLineNumber;
  38     intptr_t sourceID;
  39     UString urlString;
  40     JSValue function;
  41
  42     interpreter()->retrieveLastCaller(this, signedLineNumber, sourceID, urlString, function);
  43     dataLog("Callpoint => %s:%d\n", urlString.utf8().data(), signedLineNumber);
  44 }
  45
  46 RegisterFile* CallFrame::registerFile()
  47 {
  48     return &interpreter()->registerFile();
  49 }
  50
  51 #endif
  52
  53 #if USE(JSVALUE32_64)
  54 unsigned CallFrame::bytecodeOffsetForNonDFGCode() const
  55 {
  56     ASSERT(codeBlock());
  57     return currentVPC() - codeBlock()->instructions().begin();
  58 }
  59
  60 void CallFrame::setBytecodeOffsetForNonDFGCode(unsigned offset)
  61 {
  62     ASSERT(codeBlock());
  63     setCurrentVPC(codeBlock()->instructions().begin() + offset);
  64 }
  65 #else
  66 Instruction* CallFrame::currentVPC() const
  67 {
  68     return codeBlock()->instructions().begin() + bytecodeOffsetForNonDFGCode();
  69 }
  70 void CallFrame::setCurrentVPC(Instruction* vpc)
  71 {
  72     setBytecodeOffsetForNonDFGCode(vpc - codeBlock()->instructions().begin());
  73 }
  74 #endif
  75
  76 #if ENABLE(DFG_JIT)
  77 bool CallFrame::isInlineCallFrameSlow()
  78 {
  79     if (!callee())
  80         return false;
  81     JSCell* calleeAsFunctionCell = getJSFunction(callee());
  82     if (!calleeAsFunctionCell)
  83         return false;
  84     JSFunction* calleeAsFunction = jsCast<JSFunction*>(calleeAsFunctionCell);
  85     return calleeAsFunction->executable() != codeBlock()->ownerExecutable();
  86 }
  87
  88 CallFrame* CallFrame::trueCallFrame(AbstractPC pc)
  89 {
  90     // Am I an inline call frame? If so, we're done.
  91     if (isInlineCallFrame())
  92         return this;
  93
  94     // If I don't have a code block, then I'm not DFG code, so I'm the true call frame.
  95     CodeBlock* machineCodeBlock = codeBlock();
  96     if (!machineCodeBlock)
  97         return this;
  98
  99     // If the code block does not have any code origins, then there was no inlining, so
 100     // I'm done.
 101     if (!machineCodeBlock->hasCodeOrigins())
 102         return this;
 103
 104     // At this point the PC must be due either to the DFG, or it must be unset.
 105     ASSERT(pc.hasJITReturnAddress() || !pc);
 106
 107     // Try to determine the CodeOrigin. If we don't have a pc set then the only way
 108     // that this makes sense is if the CodeOrigin index was set in the call frame.
 109     // FIXME: Note that you will see "Not currently in inlined code" comments below.
 110     // Currently, we do not record code origins for code that is not inlined, because
 111     // the only thing that we use code origins for is determining the inline stack.
 112     // But in the future, we'll want to use this same functionality (having a code
 113     // origin mapping for any calls out of JIT code) to determine the PC at any point
 114     // in the stack even if not in inlined code. When that happens, the code below
 115     // will have to change the way it detects the presence of inlining: it will always
 116     // get a code origin, but sometimes, that code origin will not have an inline call
 117     // frame. In that case, this method should bail and return this.
 118     CodeOrigin codeOrigin;
 119     if (pc.isSet()) {
 120         ReturnAddressPtr currentReturnPC = pc.jitReturnAddress();
 121
 122         bool hasCodeOrigin = machineCodeBlock->codeOriginForReturn(currentReturnPC, codeOrigin);
 123         ASSERT_UNUSED(hasCodeOrigin, hasCodeOrigin);
 124     } else {
 125         unsigned index = codeOriginIndexForDFG();
 126         codeOrigin = machineCodeBlock->codeOrigin(index);
 127     }
 128
 129     if (!codeOrigin.inlineCallFrame)
 130         return this; // Not currently in inlined code.
 131
 132     for (InlineCallFrame* inlineCallFrame = codeOrigin.inlineCallFrame; inlineCallFrame;) {
 133         InlineCallFrame* nextInlineCallFrame = inlineCallFrame->caller.inlineCallFrame;
 134
 135         CallFrame* inlinedCaller = this + inlineCallFrame->stackOffset;
 136
 137         JSFunction* calleeAsFunction = inlineCallFrame->callee.get();
 138
 139         // Fill in the inlinedCaller
 140         inlinedCaller->setCodeBlock(machineCodeBlock);
 141
 142         inlinedCaller->setScopeChain(calleeAsFunction->scope());
 143         if (nextInlineCallFrame)
 144             inlinedCaller->setCallerFrame(this + nextInlineCallFrame->stackOffset);
 145         else
 146             inlinedCaller->setCallerFrame(this);
 147
 148         inlinedCaller->setInlineCallFrame(inlineCallFrame);
 149         inlinedCaller->setArgumentCountIncludingThis(inlineCallFrame->arguments.size());
 150         inlinedCaller->setCallee(calleeAsFunction);
 151
 152         inlineCallFrame = nextInlineCallFrame;
 153     }
 154
 155     return this + codeOrigin.inlineCallFrame->stackOffset;
 156 }
 157
 158 CallFrame* CallFrame::trueCallerFrame()
 159 {
 160     // this -> The callee; this is either an inlined callee in which case it already has
 161     //    a pointer to the true caller. Otherwise it contains current PC in the machine
 162     //    caller.
 163     //
 164     // machineCaller -> The caller according to the machine, which may be zero or
 165     //    more frames above the true caller due to inlining.
 166
 167     // Am I an inline call frame? If so, we're done.
 168     if (isInlineCallFrame())
 169         return callerFrame()->removeHostCallFrameFlag();
 170
 171     // I am a machine call frame, so the question is: is my caller a machine call frame
 172     // that has inlines or a machine call frame that doesn't?
 173     CallFrame* machineCaller = callerFrame()->removeHostCallFrameFlag();
 174     if (!machineCaller)
 175         return 0;
 176     ASSERT(!machineCaller->isInlineCallFrame());
 177
 178     // Figure out how we want to get the current code location.
 179     if (!hasReturnPC() || returnAddressIsInCtiTrampoline(returnPC()))
 180         return machineCaller->trueCallFrameFromVMCode()->removeHostCallFrameFlag();
 181
 182     return machineCaller->trueCallFrame(returnPC())->removeHostCallFrameFlag();
 183 }
 184 #endif
 185
 186 Register* CallFrame::frameExtentInternal()
 187 {
 188     CodeBlock* codeBlock = this->codeBlock();
 189     ASSERT(codeBlock);
 190     return registers() + codeBlock->m_numCalleeRegisters;
 191 }
 192
 193 }