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diff --git a/Source/JavaScriptCore/jit/JITNegGenerator.cpp b/Source/JavaScriptCore/jit/JITNegGenerator.cpp
new file mode 100644
index 000000000..c6851676d
--- /dev/null
+++ b/Source/JavaScriptCore/jit/JITNegGenerator.cpp
@@ -0,0 +1,72 @@
+/*
+ * 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 "JITNegGenerator.h"
+
+#if ENABLE(JIT)
+
+namespace JSC {
+
+void JITNegGenerator::generateFastPath(CCallHelpers& jit)
+{
+    ASSERT(m_scratchGPR != m_src.payloadGPR());
+    ASSERT(m_scratchGPR != m_result.payloadGPR());
+    ASSERT(m_scratchGPR != InvalidGPRReg);
+#if USE(JSVALUE32_64)
+    ASSERT(m_scratchGPR != m_src.tagGPR());
+    ASSERT(m_scratchGPR != m_result.tagGPR());
+#endif
+
+    m_didEmitFastPath = true;
+
+    jit.moveValueRegs(m_src, m_result);
+    CCallHelpers::Jump srcNotInt = jit.branchIfNotInt32(m_src);
+
+    // -0 should produce a double, and hence cannot be negated as an int.
+    // The negative int32 0x80000000 doesn't have a positive int32 representation, and hence cannot be negated as an int.
+    m_slowPathJumpList.append(jit.branchTest32(CCallHelpers::Zero, m_src.payloadGPR(), CCallHelpers::TrustedImm32(0x7fffffff)));
+
+    jit.neg32(m_result.payloadGPR());
+#if USE(JSVALUE64)
+    jit.boxInt32(m_result.payloadGPR(), m_result);
+#endif
+    m_endJumpList.append(jit.jump());
+
+    srcNotInt.link(&jit);
+    m_slowPathJumpList.append(jit.branchIfNotNumber(m_src, m_scratchGPR));
+
+    // For a double, all we need to do is to invert the sign bit.
+#if USE(JSVALUE64)
+    jit.move(CCallHelpers::TrustedImm64((int64_t)(1ull << 63)), m_scratchGPR);
+    jit.xor64(m_scratchGPR, m_result.payloadGPR());
+#else
+    jit.xor32(CCallHelpers::TrustedImm32(1 << 31), m_result.tagGPR());
+#endif
+}
+
+} // namespace JSC
+
+#endif // ENABLE(JIT)