diff graal/com.oracle.jvmci.bytecode/src/com/oracle/jvmci/bytecode/BytecodeSwitch.java @ 21713:454a99ca00a9

fixed canonicalizeprojects issues
author Doug Simon <doug.simon@oracle.com>
date Wed, 03 Jun 2015 22:13:10 +0200
parents graal/com.oracle.jvmci.bytecode/src/com/oracle/graal/bytecode/BytecodeSwitch.java@1c41d00e6b2f
children
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.jvmci.bytecode/src/com/oracle/jvmci/bytecode/BytecodeSwitch.java	Wed Jun 03 22:13:10 2015 +0200
@@ -0,0 +1,124 @@
+/*
+ * Copyright (c) 2009, 2011, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.oracle.jvmci.bytecode;
+
+/**
+ * An abstract class that provides the state and methods common to {@link Bytecodes#LOOKUPSWITCH}
+ * and {@link Bytecodes#TABLESWITCH} instructions.
+ */
+public abstract class BytecodeSwitch {
+
+    /**
+     * The {@link BytecodeStream} containing the bytecode array.
+     */
+    protected final BytecodeStream stream;
+    /**
+     * Index of start of switch instruction.
+     */
+    protected final int bci;
+    /**
+     * Index of the start of the additional data for the switch instruction, aligned to a multiple
+     * of four from the method start.
+     */
+    protected final int alignedBci;
+
+    /**
+     * Constructor for a {@link BytecodeStream}.
+     *
+     * @param stream the {@code BytecodeStream} containing the switch instruction
+     * @param bci the index in the stream of the switch instruction
+     */
+    public BytecodeSwitch(BytecodeStream stream, int bci) {
+        this.stream = stream;
+        this.bci = bci;
+        this.alignedBci = (bci + 4) & 0xfffffffc;
+    }
+
+    /**
+     * Gets the current bytecode index.
+     *
+     * @return the current bytecode index
+     */
+    public int bci() {
+        return bci;
+    }
+
+    /**
+     * Gets the index of the instruction denoted by the {@code i}'th switch target.
+     *
+     * @param i index of the switch target
+     * @return the index of the instruction denoted by the {@code i}'th switch target
+     */
+    public int targetAt(int i) {
+        return bci + offsetAt(i);
+    }
+
+    /**
+     * Gets the index of the instruction for the default switch target.
+     *
+     * @return the index of the instruction for the default switch target
+     */
+    public int defaultTarget() {
+        return bci + defaultOffset();
+    }
+
+    /**
+     * Gets the offset from the start of the switch instruction to the default switch target.
+     *
+     * @return the offset to the default switch target
+     */
+    public int defaultOffset() {
+        return stream.readInt(alignedBci);
+    }
+
+    /**
+     * Gets the key at {@code i}'th switch target index.
+     *
+     * @param i the switch target index
+     * @return the key at {@code i}'th switch target index
+     */
+    public abstract int keyAt(int i);
+
+    /**
+     * Gets the offset from the start of the switch instruction for the {@code i}'th switch target.
+     *
+     * @param i the switch target index
+     * @return the offset to the {@code i}'th switch target
+     */
+    public abstract int offsetAt(int i);
+
+    /**
+     * Gets the number of switch targets.
+     *
+     * @return the number of switch targets
+     */
+    public abstract int numberOfCases();
+
+    /**
+     * Gets the total size in bytes of the switch instruction.
+     *
+     * @return the total size in bytes of the switch instruction
+     */
+    public abstract int size();
+
+}