JavaScriptCore-1097.3.tar.gz

[apple/javascriptcore.git] / bytecode / CodeOrigin.h

diff --git a/bytecode/CodeOrigin.h b/bytecode/CodeOrigin.h
new file mode 100644 (file)
index 0000000..eda1764
--- /dev/null
+++ b/bytecode/CodeOrigin.h
@@ -0,0 +1,149 @@
+/*
+ * Copyright (C) 2011 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. 
+ */
+
+#ifndef CodeOrigin_h
+#define CodeOrigin_h
+
+#include "ValueRecovery.h"
+#include "WriteBarrier.h"
+#include <wtf/StdLibExtras.h>
+#include <wtf/Vector.h>
+
+namespace JSC {
+
+struct InlineCallFrame;
+class ExecutableBase;
+class JSFunction;
+
+struct CodeOrigin {
+    // Bytecode offset that you'd use to re-execute this instruction.
+    unsigned bytecodeIndex : 29;
+    // Bytecode offset corresponding to the opcode that gives the result (needed to handle
+    // op_call/op_call_put_result and op_method_check/op_get_by_id).
+    unsigned valueProfileOffset : 3;
+    
+    InlineCallFrame* inlineCallFrame;
+    
+    CodeOrigin()
+        : bytecodeIndex(std::numeric_limits<uint32_t>::max())
+        , valueProfileOffset(0)
+        , inlineCallFrame(0)
+    {
+    }
+    
+    explicit CodeOrigin(unsigned bytecodeIndex, InlineCallFrame* inlineCallFrame = 0, unsigned valueProfileOffset = 0)
+        : bytecodeIndex(bytecodeIndex)
+        , valueProfileOffset(valueProfileOffset)
+        , inlineCallFrame(inlineCallFrame)
+    {
+        ASSERT(bytecodeIndex < (1u << 29));
+        ASSERT(valueProfileOffset < (1u << 3));
+    }
+    
+    bool isSet() const { return bytecodeIndex != std::numeric_limits<uint32_t>::max(); }
+    
+    unsigned bytecodeIndexForValueProfile() const
+    {
+        return bytecodeIndex + valueProfileOffset;
+    }
+    
+    // The inline depth is the depth of the inline stack, so 1 = not inlined,
+    // 2 = inlined one deep, etc.
+    unsigned inlineDepth() const;
+    
+    // If the code origin corresponds to inlined code, gives you the heap object that
+    // would have owned the code if it had not been inlined. Otherwise returns 0.
+    ExecutableBase* codeOriginOwner() const;
+    
+    static unsigned inlineDepthForCallFrame(InlineCallFrame*);
+    
+    bool operator==(const CodeOrigin& other) const;
+    
+    bool operator!=(const CodeOrigin& other) const { return !(*this == other); }
+    
+    // Get the inline stack. This is slow, and is intended for debugging only.
+    Vector<CodeOrigin> inlineStack() const;
+};
+
+struct InlineCallFrame {
+    Vector<ValueRecovery> arguments;
+    WriteBarrier<ExecutableBase> executable;
+    WriteBarrier<JSFunction> callee;
+    CodeOrigin caller;
+    unsigned stackOffset : 31;
+    bool isCall : 1;
+};
+
+struct CodeOriginAtCallReturnOffset {
+    CodeOrigin codeOrigin;
+    unsigned callReturnOffset;
+};
+
+inline unsigned CodeOrigin::inlineDepthForCallFrame(InlineCallFrame* inlineCallFrame)
+{
+    unsigned result = 1;
+    for (InlineCallFrame* current = inlineCallFrame; current; current = current->caller.inlineCallFrame)
+        result++;
+    return result;
+}
+
+inline unsigned CodeOrigin::inlineDepth() const
+{
+    return inlineDepthForCallFrame(inlineCallFrame);
+}
+    
+inline bool CodeOrigin::operator==(const CodeOrigin& other) const
+{
+    return bytecodeIndex == other.bytecodeIndex
+        && inlineCallFrame == other.inlineCallFrame;
+}
+    
+// Get the inline stack. This is slow, and is intended for debugging only.
+inline Vector<CodeOrigin> CodeOrigin::inlineStack() const
+{
+    Vector<CodeOrigin> result(inlineDepth());
+    result.last() = *this;
+    unsigned index = result.size() - 2;
+    for (InlineCallFrame* current = inlineCallFrame; current; current = current->caller.inlineCallFrame)
+        result[index--] = current->caller;
+    return result;
+}
+
+inline unsigned getCallReturnOffsetForCodeOrigin(CodeOriginAtCallReturnOffset* data)
+{
+    return data->callReturnOffset;
+}
+
+inline ExecutableBase* CodeOrigin::codeOriginOwner() const
+{
+    if (!inlineCallFrame)
+        return 0;
+    return inlineCallFrame->executable.get();
+}
+
+} // namespace JSC
+
+#endif // CodeOrigin_h
+