webkitgtk-2.16.5HEADwebkitgtk-2.16.5master

1 files changed, 118 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/dfg/DFGArgumentsUtilities.cpp b/Source/JavaScriptCore/dfg/DFGArgumentsUtilities.cpp
new file mode 100644
index 000000000..061a284cf
--- /dev/null
+++ b/Source/JavaScriptCore/dfg/DFGArgumentsUtilities.cpp
@@ -0,0 +1,118 @@
+/*
+ * 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 "DFGArgumentsUtilities.h"
+
+#if ENABLE(DFG_JIT)
+
+#include "JSCInlines.h"
+
+namespace JSC { namespace DFG {
+
+bool argumentsInvolveStackSlot(InlineCallFrame* inlineCallFrame, VirtualRegister reg)
+{
+    if (!inlineCallFrame)
+        return (reg.isArgument() && reg.toArgument()) || reg.isHeader();
+    
+    if (inlineCallFrame->isClosureCall
+        && reg == VirtualRegister(inlineCallFrame->stackOffset + CallFrameSlot::callee))
+        return true;
+    
+    if (inlineCallFrame->isVarargs()
+        && reg == VirtualRegister(inlineCallFrame->stackOffset + CallFrameSlot::argumentCount))
+        return true;
+    
+    unsigned numArguments = inlineCallFrame->arguments.size() - 1;
+    VirtualRegister argumentStart =
+        VirtualRegister(inlineCallFrame->stackOffset) + CallFrame::argumentOffset(0);
+    return reg >= argumentStart && reg < argumentStart + numArguments;
+}
+
+bool argumentsInvolveStackSlot(Node* candidate, VirtualRegister reg)
+{
+    return argumentsInvolveStackSlot(candidate->origin.semantic.inlineCallFrame, reg);
+}
+
+Node* emitCodeToGetArgumentsArrayLength(
+    InsertionSet& insertionSet, Node* arguments, unsigned nodeIndex, NodeOrigin origin)
+{
+    Graph& graph = insertionSet.graph();
+
+    DFG_ASSERT(
+        graph, arguments,
+        arguments->op() == CreateDirectArguments || arguments->op() == CreateScopedArguments
+        || arguments->op() == CreateClonedArguments || arguments->op() == CreateRest
+        || arguments->op() == PhantomDirectArguments || arguments->op() == PhantomClonedArguments || arguments->op() == PhantomCreateRest);
+    
+    InlineCallFrame* inlineCallFrame = arguments->origin.semantic.inlineCallFrame;
+
+    unsigned numberOfArgumentsToSkip = 0;
+    if (arguments->op() == CreateRest || arguments->op() == PhantomCreateRest)
+        numberOfArgumentsToSkip = arguments->numberOfArgumentsToSkip();
+    
+    if (inlineCallFrame && !inlineCallFrame->isVarargs()) {
+        unsigned argumentsSize = inlineCallFrame->arguments.size() - 1;
+        if (argumentsSize >= numberOfArgumentsToSkip)
+            argumentsSize -= numberOfArgumentsToSkip;
+        else
+            argumentsSize = 0;
+        return insertionSet.insertConstant(
+            nodeIndex, origin, jsNumber(argumentsSize));
+    }
+    
+    Node* argumentCount;
+    if (!inlineCallFrame)
+        argumentCount = insertionSet.insertNode(nodeIndex, SpecInt32Only, GetArgumentCountIncludingThis, origin);
+    else {
+        VirtualRegister argumentCountRegister(inlineCallFrame->stackOffset + CallFrameSlot::argumentCount);
+        
+        argumentCount = insertionSet.insertNode(
+            nodeIndex, SpecInt32Only, GetStack, origin,
+            OpInfo(graph.m_stackAccessData.add(argumentCountRegister, FlushedInt32)));
+    }
+
+    Node* result = insertionSet.insertNode(
+        nodeIndex, SpecInt32Only, ArithSub, origin, OpInfo(Arith::Unchecked),
+        Edge(argumentCount, Int32Use),
+        insertionSet.insertConstantForUse(
+            nodeIndex, origin, jsNumber(1 + numberOfArgumentsToSkip), Int32Use));
+
+    if (numberOfArgumentsToSkip) {
+        // The above subtraction may produce a negative number if this number is non-zero. We correct that here.
+        result = insertionSet.insertNode(
+            nodeIndex, SpecInt32Only, ArithMax, origin, 
+            Edge(result, Int32Use), 
+            insertionSet.insertConstantForUse(nodeIndex, origin, jsNumber(0), Int32Use));
+        result->setResult(NodeResultInt32);
+    }
+
+    return result;
+}
+
+} } // namespace JSC::DFG
+
+#endif // ENABLE(DFG_JIT)
+