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diff --git a/Source/JavaScriptCore/jit/JITRightShiftGenerator.cpp b/Source/JavaScriptCore/jit/JITRightShiftGenerator.cpp
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+++ b/Source/JavaScriptCore/jit/JITRightShiftGenerator.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 "JITRightShiftGenerator.h"
+
+#if ENABLE(JIT)
+
+namespace JSC {
+
+void JITRightShiftGenerator::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_leftOperand.isConstInt32() || !m_rightOperand.isConstInt32());
+
+    m_didEmitFastPath = true;
+
+    if (m_rightOperand.isConstInt32()) {
+        // Try to do (intVar >> intConstant).
+        CCallHelpers::Jump notInt = jit.branchIfNotInt32(m_left);
+
+        jit.moveValueRegs(m_left, m_result);
+        int32_t shiftAmount = m_rightOperand.asConstInt32() & 0x1f;
+        if (shiftAmount) {
+            if (m_shiftType == SignedShift)
+                jit.rshift32(CCallHelpers::Imm32(shiftAmount), m_result.payloadGPR());
+            else
+                jit.urshift32(CCallHelpers::Imm32(shiftAmount), m_result.payloadGPR());
+#if USE(JSVALUE64)
+            jit.or64(GPRInfo::tagTypeNumberRegister, m_result.payloadGPR());
+#endif
+        }
+
+        if (jit.supportsFloatingPointTruncate()) {
+            m_endJumpList.append(jit.jump()); // Terminate the above case before emitting more code.
+
+            // Try to do (doubleVar >> intConstant).
+            notInt.link(&jit);
+
+            m_slowPathJumpList.append(jit.branchIfNotNumber(m_left, m_scratchGPR));
+
+            jit.unboxDoubleNonDestructive(m_left, m_leftFPR, m_scratchGPR, m_scratchFPR);
+            m_slowPathJumpList.append(jit.branchTruncateDoubleToInt32(m_leftFPR, m_scratchGPR));
+
+            if (shiftAmount) {
+                if (m_shiftType == SignedShift)
+                    jit.rshift32(CCallHelpers::Imm32(shiftAmount), m_scratchGPR);
+                else
+                    jit.urshift32(CCallHelpers::Imm32(shiftAmount), m_scratchGPR);
+            }
+            jit.boxInt32(m_scratchGPR, m_result);
+
+        } else
+            m_slowPathJumpList.append(notInt);
+
+    } else {
+        // Try to do (intConstant >> intVar) or (intVar >> intVar).
+        m_slowPathJumpList.append(jit.branchIfNotInt32(m_right));
+
+        GPRReg rightOperandGPR = m_right.payloadGPR();
+        if (rightOperandGPR == m_result.payloadGPR())
+            rightOperandGPR = m_scratchGPR;
+
+        CCallHelpers::Jump leftNotInt;
+        if (m_leftOperand.isConstInt32()) {
+            jit.move(m_right.payloadGPR(), rightOperandGPR);
+#if USE(JSVALUE32_64)
+            jit.move(m_right.tagGPR(), m_result.tagGPR());
+#endif
+            jit.move(CCallHelpers::Imm32(m_leftOperand.asConstInt32()), m_result.payloadGPR());
+        } else {
+            leftNotInt = jit.branchIfNotInt32(m_left);
+            jit.move(m_right.payloadGPR(), rightOperandGPR);
+            jit.moveValueRegs(m_left, m_result);
+        }
+
+        if (m_shiftType == SignedShift)
+            jit.rshift32(rightOperandGPR, m_result.payloadGPR());
+        else
+            jit.urshift32(rightOperandGPR, m_result.payloadGPR());
+#if USE(JSVALUE64)
+        jit.or64(GPRInfo::tagTypeNumberRegister, m_result.payloadGPR());
+#endif
+        if (m_leftOperand.isConstInt32())
+            return;
+
+        if (jit.supportsFloatingPointTruncate()) {
+            m_endJumpList.append(jit.jump()); // Terminate the above case before emitting more code.
+
+            // Try to do (doubleVar >> intVar).
+            leftNotInt.link(&jit);
+
+            m_slowPathJumpList.append(jit.branchIfNotNumber(m_left, m_scratchGPR));
+            jit.unboxDoubleNonDestructive(m_left, m_leftFPR, m_scratchGPR, m_scratchFPR);
+            m_slowPathJumpList.append(jit.branchTruncateDoubleToInt32(m_leftFPR, m_scratchGPR));
+
+            if (m_shiftType == SignedShift)
+                jit.rshift32(m_right.payloadGPR(), m_scratchGPR);
+            else
+                jit.urshift32(m_right.payloadGPR(), m_scratchGPR);
+            jit.boxInt32(m_scratchGPR, m_result);
+
+        } else
+            m_slowPathJumpList.append(leftNotInt);
+    }
+}
+
+} // namespace JSC
+
+#endif // ENABLE(JIT)