JavaScriptCore-1218.tar.gz

[apple/javascriptcore.git] / bytecode / ArrayProfile.cpp

diff --git a/bytecode/ArrayProfile.cpp b/bytecode/ArrayProfile.cpp
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+++ b/bytecode/ArrayProfile.cpp
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+/*
+ * Copyright (C) 2012 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 "ArrayProfile.h"
+
+#include "CodeBlock.h"
+#include <wtf/StringExtras.h>
+#include <wtf/StringPrintStream.h>
+
+namespace JSC {
+
+void dumpArrayModes(PrintStream& out, ArrayModes arrayModes)
+{
+    if (!arrayModes) {
+        out.print("0:<empty>");
+        return;
+    }
+    
+    if (arrayModes == ALL_ARRAY_MODES) {
+        out.print("TOP");
+        return;
+    }
+    
+    out.print(arrayModes, ":");
+    
+    if (arrayModes & asArrayModes(NonArray))
+        out.print("NonArray");
+    if (arrayModes & asArrayModes(NonArrayWithInt32))
+        out.print("NonArrayWithInt32");
+    if (arrayModes & asArrayModes(NonArrayWithDouble))
+        out.print("NonArrayWithDouble");
+    if (arrayModes & asArrayModes(NonArrayWithContiguous))
+        out.print("NonArrayWithContiguous");
+    if (arrayModes & asArrayModes(NonArrayWithArrayStorage))
+        out.print("NonArrayWithArrayStorage");
+    if (arrayModes & asArrayModes(NonArrayWithSlowPutArrayStorage))
+        out.print("NonArrayWithSlowPutArrayStorage");
+    if (arrayModes & asArrayModes(ArrayClass))
+        out.print("ArrayClass");
+    if (arrayModes & asArrayModes(ArrayWithUndecided))
+        out.print("ArrayWithUndecided");
+    if (arrayModes & asArrayModes(ArrayWithInt32))
+        out.print("ArrayWithInt32");
+    if (arrayModes & asArrayModes(ArrayWithDouble))
+        out.print("ArrayWithDouble");
+    if (arrayModes & asArrayModes(ArrayWithContiguous))
+        out.print("ArrayWithContiguous");
+    if (arrayModes & asArrayModes(ArrayWithArrayStorage))
+        out.print("ArrayWithArrayStorage");
+    if (arrayModes & asArrayModes(ArrayWithSlowPutArrayStorage))
+        out.print("ArrayWithSlowPutArrayStorage");
+}
+
+ArrayModes ArrayProfile::updatedObservedArrayModes() const
+{
+    if (m_lastSeenStructure)
+        return m_observedArrayModes | arrayModeFromStructure(m_lastSeenStructure);
+    return m_observedArrayModes;
+}
+
+void ArrayProfile::computeUpdatedPrediction(CodeBlock* codeBlock, OperationInProgress operation)
+{
+    const bool verbose = false;
+    
+    if (m_lastSeenStructure) {
+        m_observedArrayModes |= arrayModeFromStructure(m_lastSeenStructure);
+        m_mayInterceptIndexedAccesses |=
+            m_lastSeenStructure->typeInfo().interceptsGetOwnPropertySlotByIndexEvenWhenLengthIsNotZero();
+        if (!codeBlock->globalObject()->isOriginalArrayStructure(m_lastSeenStructure))
+            m_usesOriginalArrayStructures = false;
+        if (!structureIsPolymorphic()) {
+            if (!m_expectedStructure)
+                m_expectedStructure = m_lastSeenStructure;
+            else if (m_expectedStructure != m_lastSeenStructure) {
+                if (verbose)
+                    dataLog(*codeBlock, " bc#", m_bytecodeOffset, ": making structure polymorphic because ", RawPointer(m_expectedStructure), " (", m_expectedStructure->classInfo()->className, ") != ", RawPointer(m_lastSeenStructure), " (", m_lastSeenStructure->classInfo()->className, ")\n");
+                m_expectedStructure = polymorphicStructure();
+            }
+        }
+        m_lastSeenStructure = 0;
+    }
+    
+    if (hasTwoOrMoreBitsSet(m_observedArrayModes)) {
+        if (verbose)
+            dataLog(*codeBlock, " bc#", m_bytecodeOffset, ": making structure polymorphic because two or more bits are set in m_observedArrayModes\n");
+        m_expectedStructure = polymorphicStructure();
+    }
+    
+    if (operation == Collection
+        && expectedStructure()
+        && !Heap::isMarked(m_expectedStructure)) {
+        if (verbose)
+            dataLog(*codeBlock, " bc#", m_bytecodeOffset, ": making structure during GC\n");
+        m_expectedStructure = polymorphicStructure();
+    }
+}
+
+CString ArrayProfile::briefDescription(CodeBlock* codeBlock)
+{
+    computeUpdatedPrediction(codeBlock);
+    
+    StringPrintStream out;
+    
+    bool hasPrinted = false;
+    
+    if (m_observedArrayModes) {
+        if (hasPrinted)
+            out.print(", ");
+        out.print(ArrayModesDump(m_observedArrayModes));
+        hasPrinted = true;
+    }
+    
+    if (structureIsPolymorphic()) {
+        if (hasPrinted)
+            out.print(", ");
+        out.print("struct = TOP");
+        hasPrinted = true;
+    } else if (m_expectedStructure) {
+        if (hasPrinted)
+            out.print(", ");
+        out.print("struct = ", RawPointer(m_expectedStructure));
+        hasPrinted = true;
+    }
+    
+    if (m_mayStoreToHole) {
+        if (hasPrinted)
+            out.print(", ");
+        out.print("Hole");
+        hasPrinted = true;
+    }
+    
+    if (m_outOfBounds) {
+        if (hasPrinted)
+            out.print(", ");
+        out.print("OutOfBounds");
+        hasPrinted = true;
+    }
+    
+    if (m_mayInterceptIndexedAccesses) {
+        if (hasPrinted)
+            out.print(", ");
+        out.print("Intercept");
+        hasPrinted = true;
+    }
+    
+    if (m_usesOriginalArrayStructures) {
+        if (hasPrinted)
+            out.print(", ");
+        out.print("Original");
+        hasPrinted = true;
+    }
+    
+    UNUSED_PARAM(hasPrinted);
+    
+    return out.toCString();
+}
+
+} // namespace JSC
+