diff graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/BinaryConditionProfile.java @ 16852:3c114b3e08c3

Truffle: renamed BooleanConditionProfile to BinaryConditionProfile and IntegerConditionProfile to CountingConditionProfile.
author Christian Humer <christian.humer@gmail.com>
date Mon, 18 Aug 2014 19:00:20 +0200
parents graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/BooleanConditionProfile.java@2834af86f398
children fc6f12ee71e5
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/BinaryConditionProfile.java	Mon Aug 18 19:00:20 2014 +0200
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2013, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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.truffle.api.utilities;
+
+import com.oracle.truffle.api.*;
+import com.oracle.truffle.api.CompilerDirectives.*;
+
+/**
+ * Utility class to speculate on conditions to be never true or to be never false. Condition
+ * profiles are intended to be used as part of if conditions.
+ *
+ * Example usage:
+ *
+ * <pre>
+ * private final ConditionProfile zero = new BooleanConditionProfile();
+ * 
+ * int value = ...;
+ * if (zero.profile(value == 0)) {
+ *   return 0;
+ * } else {
+ *   return value;
+ * }
+ *
+ * </pre>
+ *
+ * @see ConditionProfile
+ * @see CountingConditionProfile
+ */
+public class BinaryConditionProfile extends ConditionProfile {
+
+    @CompilationFinal private boolean wasTrue;
+    @CompilationFinal private boolean wasFalse;
+
+    @Override
+    public boolean profile(boolean value) {
+        if (value) {
+            if (!wasTrue) {
+                CompilerDirectives.transferToInterpreterAndInvalidate();
+                wasTrue = true;
+            }
+        } else {
+            if (!wasFalse) {
+                CompilerDirectives.transferToInterpreterAndInvalidate();
+                wasFalse = true;
+            }
+        }
+        return value;
+    }
+
+    public boolean wasTrue() {
+        return wasTrue;
+    }
+
+    public boolean wasFalse() {
+        return wasFalse;
+    }
+
+    @Override
+    public String toString() {
+        return String.format("%s(wasTrue=%s, wasFalse=%s)@%x", getClass().getSimpleName(), wasTrue, wasFalse, hashCode());
+    }
+}