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diff --git a/Source/JavaScriptCore/jit/JITDivGenerator.cpp b/Source/JavaScriptCore/jit/JITDivGenerator.cpp
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+++ b/Source/JavaScriptCore/jit/JITDivGenerator.cpp
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+/*
+ * Copyright (C) 2015 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.
+ */
+
+#include "config.h"
+#include "JITDivGenerator.h"
+
+#if ENABLE(JIT)
+
+#include "JSCJSValueInlines.h"
+
+namespace JSC {
+
+void JITDivGenerator::loadOperand(CCallHelpers& jit, SnippetOperand& opr, JSValueRegs oprRegs, FPRReg destFPR)
+{
+    if (opr.isConstInt32()) {
+        jit.move(CCallHelpers::Imm32(opr.asConstInt32()), m_scratchGPR);
+        jit.convertInt32ToDouble(m_scratchGPR, destFPR);
+#if USE(JSVALUE64)
+    } else if (opr.isConstDouble()) {
+        jit.move(CCallHelpers::Imm64(opr.asRawBits()), m_scratchGPR);
+        jit.move64ToDouble(m_scratchGPR, destFPR);
+#endif
+    } else {
+        if (!opr.definitelyIsNumber())
+            m_slowPathJumpList.append(jit.branchIfNotNumber(oprRegs, m_scratchGPR));
+        CCallHelpers::Jump notInt32 = jit.branchIfNotInt32(oprRegs);
+        jit.convertInt32ToDouble(oprRegs.payloadGPR(), destFPR);
+        CCallHelpers::Jump oprIsLoaded = jit.jump();
+        notInt32.link(&jit);
+        jit.unboxDoubleNonDestructive(oprRegs, destFPR, m_scratchGPR, m_scratchFPR);
+        oprIsLoaded.link(&jit);
+    }
+}
+
+void JITDivGenerator::generateFastPath(CCallHelpers& jit)
+{
+    ASSERT(m_scratchGPR != InvalidGPRReg);
+    ASSERT(m_scratchGPR != m_left.payloadGPR());
+    ASSERT(m_scratchGPR != m_right.payloadGPR());
+#if USE(JSVALUE32_64)
+    ASSERT(m_scratchGPR != m_left.tagGPR());
+    ASSERT(m_scratchGPR != m_right.tagGPR());
+    ASSERT(m_scratchFPR != InvalidFPRReg);
+#endif
+
+    ASSERT(!m_didEmitFastPath);
+    if (!jit.supportsFloatingPoint())
+        return;
+    if (!m_leftOperand.mightBeNumber() || !m_rightOperand.mightBeNumber())
+        return;
+
+    ASSERT(!m_leftOperand.isConstInt32() || !m_rightOperand.isConstInt32());
+    m_didEmitFastPath = true;
+    loadOperand(jit, m_leftOperand, m_left, m_leftFPR);
+    loadOperand(jit, m_rightOperand, m_right, m_rightFPR);
+
+    jit.divDouble(m_rightFPR, m_leftFPR);
+
+    // Is the result actually an integer? The DFG JIT would really like to know. If it's
+    // not an integer, we increment a count. If this together with the slow case counter
+    // are below threshold then the DFG JIT will compile this division with a speculation
+    // that the remainder is zero.
+
+    // As well, there are cases where a double result here would cause an important field
+    // in the heap to sometimes have doubles in it, resulting in double predictions getting
+    // propagated to a use site where it might cause damage (such as the index to an array
+    // access). So if we are DFG compiling anything in the program, we want this code to
+    // ensure that it produces integers whenever possible.
+    
+    CCallHelpers::JumpList notInt32;
+    jit.branchConvertDoubleToInt32(m_leftFPR, m_scratchGPR, notInt32, m_scratchFPR);
+
+    // If we've got an integer, we might as well make that the result of the division.
+    jit.boxInt32(m_scratchGPR, m_result);
+    m_endJumpList.append(jit.jump());
+
+    notInt32.link(&jit);
+#if USE(JSVALUE64)
+    jit.moveDoubleTo64(m_leftFPR, m_scratchGPR);
+    CCallHelpers::Jump notDoubleZero = jit.branchTest64(CCallHelpers::NonZero, m_scratchGPR);
+
+    jit.move(GPRInfo::tagTypeNumberRegister, m_result.payloadGPR());
+    m_endJumpList.append(jit.jump());
+
+    notDoubleZero.link(&jit);
+#endif
+    if (m_resultProfile)
+        jit.add32(CCallHelpers::TrustedImm32(1), CCallHelpers::AbsoluteAddress(m_resultProfile->addressOfSpecialFastPathCount()));
+    jit.boxDouble(m_leftFPR, m_result);
+}
+
+} // namespace JSC
+
+#endif // ENABLE(JIT)