1 files changed, 91 insertions, 0 deletions
diff --git a/Source/JavaScriptCore/jit/JITSubGenerator.cpp b/Source/JavaScriptCore/jit/JITSubGenerator.cpp
new file mode 100644
index 000000000..3ebaaa372
--- /dev/null
+++ b/Source/JavaScriptCore/jit/JITSubGenerator.cpp
@@ -0,0 +1,91 @@
+/*
+ * 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 "JITSubGenerator.h"
+
+#if ENABLE(JIT)
+
+namespace JSC {
+
+void JITSubGenerator::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
+
+    m_didEmitFastPath = true;
+
+    CCallHelpers::Jump leftNotInt = jit.branchIfNotInt32(m_left);
+    CCallHelpers::Jump rightNotInt = jit.branchIfNotInt32(m_right);
+
+    jit.move(m_left.payloadGPR(), m_scratchGPR);
+    m_slowPathJumpList.append(jit.branchSub32(CCallHelpers::Overflow, m_right.payloadGPR(), m_scratchGPR));
+
+    jit.boxInt32(m_scratchGPR, m_result);
+
+    m_endJumpList.append(jit.jump());
+
+    if (!jit.supportsFloatingPoint()) {
+        m_slowPathJumpList.append(leftNotInt);
+        m_slowPathJumpList.append(rightNotInt);
+        return;
+    }
+
+    leftNotInt.link(&jit);
+    if (!m_leftOperand.definitelyIsNumber())
+        m_slowPathJumpList.append(jit.branchIfNotNumber(m_left, m_scratchGPR));
+    if (!m_rightOperand.definitelyIsNumber())
+        m_slowPathJumpList.append(jit.branchIfNotNumber(m_right, m_scratchGPR));
+
+    jit.unboxDoubleNonDestructive(m_left, m_leftFPR, m_scratchGPR, m_scratchFPR);
+    CCallHelpers::Jump rightIsDouble = jit.branchIfNotInt32(m_right);
+
+    jit.convertInt32ToDouble(m_right.payloadGPR(), m_rightFPR);
+    CCallHelpers::Jump rightWasInteger = jit.jump();
+
+    rightNotInt.link(&jit);
+    if (!m_rightOperand.definitelyIsNumber())
+        m_slowPathJumpList.append(jit.branchIfNotNumber(m_right, m_scratchGPR));
+
+    jit.convertInt32ToDouble(m_left.payloadGPR(), m_leftFPR);
+
+    rightIsDouble.link(&jit);
+    jit.unboxDoubleNonDestructive(m_right, m_rightFPR, m_scratchGPR, m_scratchFPR);
+
+    rightWasInteger.link(&jit);
+
+    jit.subDouble(m_rightFPR, m_leftFPR);
+    jit.boxDouble(m_leftFPR, m_result);
+}
+
+} // namespace JSC
+
+#endif // ENABLE(JIT)