dfg/DFGOSRExit.cpp

   1 /*
   2  * Copyright (C) 2011 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 "DFGOSRExit.h"
  28
  29 #if ENABLE(DFG_JIT)
  30
  31 #include "DFGAssemblyHelpers.h"
  32 #include "DFGSpeculativeJIT.h"
  33
  34 namespace JSC { namespace DFG {
  35
  36 static unsigned computeNumVariablesForCodeOrigin(
  37     CodeBlock* codeBlock, const CodeOrigin& codeOrigin)
  38 {
  39     if (!codeOrigin.inlineCallFrame)
  40         return codeBlock->m_numCalleeRegisters;
  41     return
  42         codeOrigin.inlineCallFrame->stackOffset +
  43         baselineCodeBlockForInlineCallFrame(codeOrigin.inlineCallFrame)->m_numCalleeRegisters;
  44 }
  45
  46 OSRExit::OSRExit(ExitKind kind, JSValueSource jsValueSource, MethodOfGettingAValueProfile valueProfile, MacroAssembler::Jump check, SpeculativeJIT* jit, unsigned recoveryIndex)
  47     : m_jsValueSource(jsValueSource)
  48     , m_valueProfile(valueProfile)
  49     , m_check(check)
  50     , m_nodeIndex(jit->m_compileIndex)
  51     , m_codeOrigin(jit->m_codeOriginForOSR)
  52     , m_codeOriginForExitProfile(m_codeOrigin)
  53     , m_recoveryIndex(recoveryIndex)
  54     , m_kind(kind)
  55     , m_count(0)
  56     , m_arguments(jit->m_arguments.size())
  57     , m_variables(computeNumVariablesForCodeOrigin(jit->m_jit.graph().m_profiledBlock, jit->m_codeOriginForOSR))
  58     , m_lastSetOperand(jit->m_lastSetOperand)
  59 {
  60     ASSERT(m_codeOrigin.isSet());
  61     for (unsigned argument = 0; argument < m_arguments.size(); ++argument)
  62         m_arguments[argument] = jit->computeValueRecoveryFor(jit->m_arguments[argument]);
  63     for (unsigned variable = 0; variable < m_variables.size(); ++variable)
  64         m_variables[variable] = jit->computeValueRecoveryFor(jit->m_variables[variable]);
  65 }
  66
  67 void OSRExit::dump(FILE* out) const
  68 {
  69     for (unsigned argument = 0; argument < m_arguments.size(); ++argument)
  70         m_arguments[argument].dump(out);
  71     fprintf(out, " : ");
  72     for (unsigned variable = 0; variable < m_variables.size(); ++variable)
  73         m_variables[variable].dump(out);
  74 }
  75
  76 bool OSRExit::considerAddingAsFrequentExitSiteSlow(CodeBlock* dfgCodeBlock, CodeBlock* profiledCodeBlock)
  77 {
  78     if (static_cast<double>(m_count) / dfgCodeBlock->speculativeFailCounter() <= Options::osrExitProminenceForFrequentExitSite)
  79         return false;
  80
  81     return baselineCodeBlockForOriginAndBaselineCodeBlock(m_codeOriginForExitProfile, profiledCodeBlock)->addFrequentExitSite(FrequentExitSite(m_codeOriginForExitProfile.bytecodeIndex, m_kind));
  82 }
  83
  84 } } // namespace JSC::DFG
  85
  86 #endif // ENABLE(DFG_JIT)