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Diffstat (limited to 'Source/JavaScriptCore/interpreter/JSStackInlines.h')
| -rw-r--r-- | Source/JavaScriptCore/interpreter/JSStackInlines.h | 295 |
1 files changed, 0 insertions, 295 deletions
diff --git a/Source/JavaScriptCore/interpreter/JSStackInlines.h b/Source/JavaScriptCore/interpreter/JSStackInlines.h deleted file mode 100644 index 5a2aff117..000000000 --- a/Source/JavaScriptCore/interpreter/JSStackInlines.h +++ /dev/null @@ -1,295 +0,0 @@ -/* - * Copyright (C) 2012, 2013 Apple Inc. All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * - * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY - * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR - * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR - * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, - * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, - * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR - * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY - * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE - * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - */ - -#ifndef JSStackInlines_h -#define JSStackInlines_h - -#include "CallFrame.h" -#include "CodeBlock.h" -#include "JSStack.h" -#include "VM.h" - -namespace JSC { - -inline Register* JSStack::getTopOfFrame(CallFrame* frame) -{ - if (UNLIKELY(!frame)) - return getBaseOfStack(); - return frame->frameExtent(); -} - -inline Register* JSStack::getTopOfStack() -{ - return getTopOfFrame(m_topCallFrame); -} - -inline Register* JSStack::getStartOfFrame(CallFrame* frame) -{ - CallFrame* callerFrame = frame->callerFrameSkippingVMEntrySentinel(); - return getTopOfFrame(callerFrame); -} - -inline bool JSStack::entryCheck(class CodeBlock* codeBlock, int argsCount) -{ - Register* oldEnd = getTopOfStack(); - - // Ensure that we have enough space for the parameters: - size_t paddedArgsCount = argsCount; - if (codeBlock) { - size_t numParameters = codeBlock->numParameters(); - if (paddedArgsCount < numParameters) - paddedArgsCount = numParameters; - } - - Register* newCallFrameSlot = oldEnd - paddedArgsCount - (2 * JSStack::CallFrameHeaderSize) + 1; - -#if ENABLE(DEBUG_JSSTACK) - newCallFrameSlot -= JSStack::FenceSize; -#endif - - Register* newEnd = newCallFrameSlot; - if (!!codeBlock) - newEnd += virtualRegisterForLocal(codeBlock->frameRegisterCount()).offset(); - - // Ensure that we have the needed stack capacity to push the new frame: - if (!grow(newEnd)) - return false; - - return true; -} - -inline CallFrame* JSStack::pushFrame(class CodeBlock* codeBlock, JSScope* scope, int argsCount, JSObject* callee) -{ - ASSERT(!!scope); - Register* oldEnd = getTopOfStack(); - - // Ensure that we have enough space for the parameters: - size_t paddedArgsCount = argsCount; - if (codeBlock) { - size_t numParameters = codeBlock->numParameters(); - if (paddedArgsCount < numParameters) - paddedArgsCount = numParameters; - } - - Register* newCallFrameSlot = oldEnd - paddedArgsCount - (2 * JSStack::CallFrameHeaderSize) + 1; - -#if ENABLE(DEBUG_JSSTACK) - newCallFrameSlot -= JSStack::FenceSize; -#endif - - Register* newEnd = newCallFrameSlot; - if (!!codeBlock) - newEnd += virtualRegisterForLocal(codeBlock->frameRegisterCount()).offset(); - - // Ensure that we have the needed stack capacity to push the new frame: - if (!grow(newEnd)) - return 0; - - // Compute the address of the new VM sentinel frame for this invocation: - CallFrame* newVMEntrySentinelFrame = CallFrame::create(newCallFrameSlot + paddedArgsCount + JSStack::CallFrameHeaderSize); - ASSERT(!!newVMEntrySentinelFrame); - - // Compute the address of the new frame for this invocation: - CallFrame* newCallFrame = CallFrame::create(newCallFrameSlot); - ASSERT(!!newCallFrame); - - // The caller frame should always be the real previous frame on the stack, - // and not a potential GlobalExec that was passed in. Point callerFrame to - // the top frame on the stack. - CallFrame* callerFrame = m_topCallFrame; - - // Initialize the VM sentinel frame header: - newVMEntrySentinelFrame->initializeVMEntrySentinelFrame(callerFrame); - - // Initialize the callee frame header: - newCallFrame->init(codeBlock, 0, scope, newVMEntrySentinelFrame, argsCount, callee); - - ASSERT(!!newCallFrame->scope()); - - // Pad additional args if needed: - // Note: we need to subtract 1 from argsCount and paddedArgsCount to - // exclude the this pointer. - for (size_t i = argsCount-1; i < paddedArgsCount-1; ++i) - newCallFrame->setArgument(i, jsUndefined()); - - installFence(newCallFrame, __FUNCTION__, __LINE__); - validateFence(newCallFrame, __FUNCTION__, __LINE__); - installTrapsAfterFrame(newCallFrame); - - // Push the new frame: - m_topCallFrame = newCallFrame; - - return newCallFrame; -} - -inline void JSStack::popFrame(CallFrame* frame) -{ - validateFence(frame, __FUNCTION__, __LINE__); - - // Pop off the callee frame and the sentinel frame. - CallFrame* callerFrame = frame->callerFrame()->vmEntrySentinelCallerFrame(); - - // Pop to the caller: - m_topCallFrame = callerFrame; - - // If we are popping the very first frame from the stack i.e. no more - // frames before this, then we can now safely shrink the stack. In - // this case, we're shrinking all the way to the beginning since there - // are no more frames on the stack. - if (!callerFrame) - shrink(getBaseOfStack()); - - installTrapsAfterFrame(callerFrame); -} - -inline void JSStack::shrink(Register* newEnd) -{ - if (newEnd >= m_end) - return; - updateStackLimit(newEnd); - if (m_end == getBaseOfStack() && (m_commitEnd - getBaseOfStack()) >= maxExcessCapacity) - releaseExcessCapacity(); -} - -inline bool JSStack::grow(Register* newEnd) -{ - if (newEnd >= m_end) - return true; - return growSlowCase(newEnd); -} - -inline void JSStack::updateStackLimit(Register* newEnd) -{ - m_end = newEnd; -#if USE(SEPARATE_C_AND_JS_STACK) - m_vm.setJSStackLimit(newEnd); -#endif -} - -#if ENABLE(DEBUG_JSSTACK) -inline JSValue JSStack::generateFenceValue(size_t argIndex) -{ - unsigned fenceBits = 0xfacebad0 | ((argIndex+1) & 0xf); - JSValue fenceValue = JSValue(fenceBits); - return fenceValue; -} - -// The JSStack fences mechanism works as follows: -// 1. A fence is a number (JSStack::FenceSize) of JSValues that are initialized -// with values generated by JSStack::generateFenceValue(). -// 2. When pushFrame() is called, the fence is installed after the max extent -// of the previous topCallFrame and the last arg of the new frame: -// -// | ... | -// |--------------------------------------| -// | Frame Header of previous frame | -// |--------------------------------------| -// topCallFrame --> | | -// | Locals of previous frame | -// |--------------------------------------| -// | *** the Fence *** | -// |--------------------------------------| -// | VM entry sentinel frame header | -// |--------------------------------------| -// | Args of new frame | -// |--------------------------------------| -// | Frame Header of new frame | -// |--------------------------------------| -// frame --> | Locals of new frame | -// | | -// -// 3. In popFrame() and elsewhere, we can call JSStack::validateFence() to -// assert that the fence contains the values we expect. - -inline void JSStack::installFence(CallFrame* frame, const char *function, int lineNo) -{ - UNUSED_PARAM(function); - UNUSED_PARAM(lineNo); - Register* startOfFrame = getStartOfFrame(frame); - - // The last argIndex is at: - size_t maxIndex = frame->argIndexForRegister(startOfFrame) + 1; - size_t startIndex = maxIndex - FenceSize; - for (size_t i = startIndex; i < maxIndex; ++i) { - JSValue fenceValue = generateFenceValue(i); - frame->setArgument(i, fenceValue); - } -} - -inline void JSStack::validateFence(CallFrame* frame, const char *function, int lineNo) -{ - UNUSED_PARAM(function); - UNUSED_PARAM(lineNo); - ASSERT(!!frame->scope()); - Register* startOfFrame = getStartOfFrame(frame); - size_t maxIndex = frame->argIndexForRegister(startOfFrame) + 1; - size_t startIndex = maxIndex - FenceSize; - for (size_t i = startIndex; i < maxIndex; ++i) { - JSValue fenceValue = generateFenceValue(i); - JSValue actualValue = frame->getArgumentUnsafe(i); - ASSERT(fenceValue == actualValue); - } -} - -// When debugging the JSStack, we install bad values after the extent of the -// topCallFrame at the end of pushFrame() and popFrame(). The intention is -// to trigger crashes in the event that memory in this supposedly unused -// region is read and consumed without proper initialization. After the trap -// words are installed, the stack looks like this: -// -// | ... | -// |-----------------------------| -// | Frame Header of frame | -// |-----------------------------| -// topCallFrame --> | | -// | Locals of frame | -// |-----------------------------| -// | *** Trap words *** | -// |-----------------------------| -// | Unused space ... | -// | ... | - -inline void JSStack::installTrapsAfterFrame(CallFrame* frame) -{ - Register* topOfFrame = getTopOfFrame(frame); - const int sizeOfTrap = 64; - int32_t* startOfTrap = reinterpret_cast<int32_t*>(topOfFrame); - int32_t* endOfTrap = startOfTrap - sizeOfTrap; - int32_t* endOfCommitedMemory = reinterpret_cast<int32_t*>(m_commitEnd); - - // Make sure we're not exceeding the amount of available memory to write to: - if (endOfTrap < endOfCommitedMemory) - endOfTrap = endOfCommitedMemory; - - // Lay the traps: - int32_t* p = startOfTrap; - while (p > endOfTrap) - *p-- = 0xabadcafe; // A bad word to trigger a crash if deref'ed. -} -#endif // ENABLE(DEBUG_JSSTACK) - -} // namespace JSC - -#endif // JSStackInlines_h |