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diff --git a/Source/JavaScriptCore/jit/JITMathIC.h b/Source/JavaScriptCore/jit/JITMathIC.h
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+++ b/Source/JavaScriptCore/jit/JITMathIC.h
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+/*
+ * Copyright (C) 2016 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. 
+ */
+
+#pragma once
+
+#if ENABLE(JIT)
+
+#include "ArithProfile.h"
+#include "CCallHelpers.h"
+#include "JITAddGenerator.h"
+#include "JITMathICInlineResult.h"
+#include "JITMulGenerator.h"
+#include "JITNegGenerator.h"
+#include "JITSubGenerator.h"
+#include "LinkBuffer.h"
+#include "Repatch.h"
+#include "SnippetOperand.h"
+
+namespace JSC {
+
+class LinkBuffer;
+
+struct MathICGenerationState {
+    MacroAssembler::Label fastPathStart;
+    MacroAssembler::Label fastPathEnd;
+    MacroAssembler::Label slowPathStart;
+    MacroAssembler::Call slowPathCall;
+    MacroAssembler::JumpList slowPathJumps;
+    bool shouldSlowPathRepatch;
+};
+
+#define ENABLE_MATH_IC_STATS 0
+
+template <typename GeneratorType, bool(*isProfileEmpty)(ArithProfile&)>
+class JITMathIC {
+public:
+    JITMathIC(ArithProfile* arithProfile)
+        : m_arithProfile(arithProfile)
+    {
+    }
+
+    CodeLocationLabel doneLocation() { return m_inlineStart.labelAtOffset(m_inlineSize); }
+    CodeLocationLabel slowPathStartLocation() { return m_inlineStart.labelAtOffset(m_deltaFromStartToSlowPathStart); }
+    CodeLocationCall slowPathCallLocation() { return m_inlineStart.callAtOffset(m_deltaFromStartToSlowPathCallLocation); }
+    
+    bool generateInline(CCallHelpers& jit, MathICGenerationState& state, bool shouldEmitProfiling = true)
+    {
+#if CPU(ARM_TRADITIONAL)
+        // FIXME: Remove this workaround once the proper fixes are landed.
+        // [ARM] Disable Inline Caching on ARMv7 traditional until proper fix
+        // https://bugs.webkit.org/show_bug.cgi?id=159759
+        return false;
+#endif
+
+        state.fastPathStart = jit.label();
+        size_t startSize = jit.m_assembler.buffer().codeSize();
+
+        if (m_arithProfile) {
+            if (isProfileEmpty(*m_arithProfile)) {
+                // It looks like the MathIC has yet to execute. We don't want to emit code in this
+                // case for a couple reasons. First, the operation may never execute, so if we don't emit
+                // code, it's a win. Second, if the operation does execute, we can emit better code
+                // once we have an idea about the types.
+                state.slowPathJumps.append(jit.patchableJump());
+                size_t inlineSize = jit.m_assembler.buffer().codeSize() - startSize;
+                ASSERT_UNUSED(inlineSize, static_cast<ptrdiff_t>(inlineSize) <= MacroAssembler::patchableJumpSize());
+                state.shouldSlowPathRepatch = true;
+                state.fastPathEnd = jit.label();
+                ASSERT(!m_generateFastPathOnRepatch); // We should have gathered some observed type info about the types before trying to regenerate again.
+                m_generateFastPathOnRepatch = true;
+                return true;
+            }
+        }
+
+        JITMathICInlineResult result = m_generator.generateInline(jit, state, m_arithProfile);
+
+        switch (result) {
+        case JITMathICInlineResult::GeneratedFastPath: {
+            size_t inlineSize = jit.m_assembler.buffer().codeSize() - startSize;
+            if (static_cast<ptrdiff_t>(inlineSize) < MacroAssembler::patchableJumpSize()) {
+                size_t nopsToEmitInBytes = MacroAssembler::patchableJumpSize() - inlineSize;
+                jit.emitNops(nopsToEmitInBytes);
+            }
+            state.shouldSlowPathRepatch = true;
+            state.fastPathEnd = jit.label();
+            return true;
+        }
+        case JITMathICInlineResult::GenerateFullSnippet: {
+            MacroAssembler::JumpList endJumpList;
+            bool result = m_generator.generateFastPath(jit, endJumpList, state.slowPathJumps, m_arithProfile, shouldEmitProfiling);
+            if (result) {
+                state.fastPathEnd = jit.label();
+                state.shouldSlowPathRepatch = false;
+                endJumpList.link(&jit);
+                return true;
+            }
+            return false;
+        }
+        case JITMathICInlineResult::DontGenerate: {
+            return false;
+        }
+        default:
+            ASSERT_NOT_REACHED();
+        }
+
+        return false;
+    }
+
+    void generateOutOfLine(VM& vm, CodeBlock* codeBlock, FunctionPtr callReplacement)
+    {
+        auto linkJumpToOutOfLineSnippet = [&] () {
+            CCallHelpers jit(&vm, codeBlock);
+            auto jump = jit.jump();
+            // We don't need a nop sled here because nobody should be jumping into the middle of an IC.
+            bool needsBranchCompaction = false;
+            RELEASE_ASSERT(jit.m_assembler.buffer().codeSize() <= static_cast<size_t>(m_inlineSize));
+            LinkBuffer linkBuffer(jit, m_inlineStart.dataLocation(), jit.m_assembler.buffer().codeSize(), JITCompilationMustSucceed, needsBranchCompaction);
+            RELEASE_ASSERT(linkBuffer.isValid());
+            linkBuffer.link(jump, CodeLocationLabel(m_code.code()));
+            FINALIZE_CODE(linkBuffer, ("JITMathIC: linking constant jump to out of line stub"));
+        };
+
+        auto replaceCall = [&] () {
+            ftlThunkAwareRepatchCall(codeBlock, slowPathCallLocation(), callReplacement);
+        };
+
+        bool shouldEmitProfiling = !JITCode::isOptimizingJIT(codeBlock->jitType());
+
+        if (m_generateFastPathOnRepatch) {
+
+            CCallHelpers jit(&vm, codeBlock);
+            MathICGenerationState generationState;
+            bool generatedInline = generateInline(jit, generationState, shouldEmitProfiling);
+
+            // We no longer want to try to regenerate the fast path.
+            m_generateFastPathOnRepatch = false;
+
+            if (generatedInline) {
+                auto jumpToDone = jit.jump();
+
+                LinkBuffer linkBuffer(vm, jit, codeBlock, JITCompilationCanFail);
+                if (!linkBuffer.didFailToAllocate()) {
+                    linkBuffer.link(generationState.slowPathJumps, slowPathStartLocation());
+                    linkBuffer.link(jumpToDone, doneLocation());
+
+                    m_code = FINALIZE_CODE_FOR(
+                        codeBlock, linkBuffer, ("JITMathIC: generating out of line fast IC snippet"));
+
+                    if (!generationState.shouldSlowPathRepatch) {
+                        // We won't need to regenerate, so we can wire the slow path call
+                        // to a non repatching variant.
+                        replaceCall();
+                    }
+
+                    linkJumpToOutOfLineSnippet();
+
+                    return;
+                }
+            }
+            
+            // We weren't able to generate an out of line fast path.
+            // We just generate the snippet in its full generality.
+        }
+
+        // We rewire to the alternate regardless of whether or not we can allocate the out of line path
+        // because if we fail allocating the out of line path, we don't want to waste time trying to
+        // allocate it in the future.
+        replaceCall();
+
+        {
+            CCallHelpers jit(&vm, codeBlock);
+
+            MacroAssembler::JumpList endJumpList; 
+            MacroAssembler::JumpList slowPathJumpList; 
+
+            bool emittedFastPath = m_generator.generateFastPath(jit, endJumpList, slowPathJumpList, m_arithProfile, shouldEmitProfiling);
+            if (!emittedFastPath)
+                return;
+            endJumpList.append(jit.jump());
+
+            LinkBuffer linkBuffer(vm, jit, codeBlock, JITCompilationCanFail);
+            if (linkBuffer.didFailToAllocate())
+                return;
+
+            linkBuffer.link(endJumpList, doneLocation());
+            linkBuffer.link(slowPathJumpList, slowPathStartLocation());
+
+            m_code = FINALIZE_CODE_FOR(
+                codeBlock, linkBuffer, ("JITMathIC: generating out of line IC snippet"));
+        }
+
+        linkJumpToOutOfLineSnippet();
+    }
+
+    void finalizeInlineCode(const MathICGenerationState& state, LinkBuffer& linkBuffer)
+    {
+        CodeLocationLabel start = linkBuffer.locationOf(state.fastPathStart);
+        m_inlineStart = start;
+
+        m_inlineSize = MacroAssembler::differenceBetweenCodePtr(
+            start, linkBuffer.locationOf(state.fastPathEnd));
+        ASSERT(m_inlineSize > 0);
+
+        m_deltaFromStartToSlowPathCallLocation = MacroAssembler::differenceBetweenCodePtr(
+            start, linkBuffer.locationOf(state.slowPathCall));
+        m_deltaFromStartToSlowPathStart = MacroAssembler::differenceBetweenCodePtr(
+            start, linkBuffer.locationOf(state.slowPathStart));
+    }
+
+    ArithProfile* arithProfile() const { return m_arithProfile; }
+
+#if ENABLE(MATH_IC_STATS)
+    size_t m_generatedCodeSize { 0 };
+    size_t codeSize() const
+    {
+        size_t result = m_generatedCodeSize;
+        if (m_code)
+            result += m_code.size();
+        return result;
+    }
+#endif
+
+    ArithProfile* m_arithProfile;
+    MacroAssemblerCodeRef m_code;
+    CodeLocationLabel m_inlineStart;
+    int32_t m_inlineSize;
+    int32_t m_deltaFromStartToSlowPathCallLocation;
+    int32_t m_deltaFromStartToSlowPathStart;
+    bool m_generateFastPathOnRepatch { false };
+    GeneratorType m_generator;
+};
+
+inline bool isBinaryProfileEmpty(ArithProfile& arithProfile)
+{
+    return arithProfile.lhsObservedType().isEmpty() || arithProfile.rhsObservedType().isEmpty();
+}
+template <typename GeneratorType>
+class JITBinaryMathIC : public JITMathIC<GeneratorType, isBinaryProfileEmpty> {
+public:
+    JITBinaryMathIC(ArithProfile* arithProfile)
+        : JITMathIC<GeneratorType, isBinaryProfileEmpty>(arithProfile)
+    {
+    }
+};
+
+typedef JITBinaryMathIC<JITAddGenerator> JITAddIC;
+typedef JITBinaryMathIC<JITMulGenerator> JITMulIC;
+typedef JITBinaryMathIC<JITSubGenerator> JITSubIC;
+
+
+inline bool isUnaryProfileEmpty(ArithProfile& arithProfile)
+{
+    return arithProfile.lhsObservedType().isEmpty();
+}
+template <typename GeneratorType>
+class JITUnaryMathIC : public JITMathIC<GeneratorType, isUnaryProfileEmpty> {
+public:
+    JITUnaryMathIC(ArithProfile* arithProfile)
+        : JITMathIC<GeneratorType, isUnaryProfileEmpty>(arithProfile)
+    {
+    }
+};
+
+typedef JITUnaryMathIC<JITNegGenerator> JITNegIC;
+
+} // namespace JSC
+
+#endif // ENABLE(JIT)