# HG changeset patch
# User Christian Humer <christian.humer@gmail.com>
# Date 1409749133 -7200
# Node ID 1e542561783e68fbde74a5d87560102f270e8bd7
# Parent  3b3e768a2b924131976840560e7222f5c29e69f2
Truffle: new value profiles prototype.

diff -r 3b3e768a2b92 -r 1e542561783e graal/com.oracle.truffle.api.test/src/com/oracle/truffle/api/test/utilities/ExactClassValueProfileTest.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.api.test/src/com/oracle/truffle/api/test/utilities/ExactClassValueProfileTest.java	Wed Sep 03 14:58:53 2014 +0200
@@ -0,0 +1,106 @@
+/*
+ * Copyright (c) 2014, 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.truffle.api.test.utilities;
+
+import static org.hamcrest.CoreMatchers.*;
+import static org.junit.Assert.*;
+
+import org.junit.*;
+import org.junit.experimental.theories.*;
+import org.junit.runner.*;
+
+import com.oracle.truffle.api.utilities.*;
+
+@RunWith(Theories.class)
+public class ExactClassValueProfileTest {
+
+    @DataPoint public static final String O1 = new String();
+    @DataPoint public static final String O2 = new String();
+    @DataPoint public static final Object O3 = new Object();
+    @DataPoint public static final Integer O4 = new Integer(1);
+    @DataPoint public static final Integer O5 = null;
+
+    private ExactClassValueProfile profile;
+
+    @Before
+    public void create() {
+        profile = (ExactClassValueProfile) ValueProfile.createClassProfile();
+    }
+
+    @Test
+    public void testInitial() {
+        assertThat(profile.isGeneric(), is(false));
+        assertThat(profile.isUninitialized(), is(true));
+        assertNull(profile.getCachedClass());
+        profile.toString(); // test that it is not crashing
+    }
+
+    @Theory
+    public void testProfileOne(Object value) {
+        Object result = profile.profile(value);
+
+        assertThat(result, is(value));
+        assertEquals(profile.getCachedClass(), expectedClass(value));
+        assertThat(profile.isUninitialized(), is(false));
+        profile.toString(); // test that it is not crashing
+    }
+
+    @Theory
+    public void testProfileTwo(Object value0, Object value1) {
+        Object result0 = profile.profile(value0);
+        Object result1 = profile.profile(value1);
+
+        assertThat(result0, is(value0));
+        assertThat(result1, is(value1));
+
+        Object expectedClass = expectedClass(value0) == expectedClass(value1) ? expectedClass(value0) : Object.class;
+
+        assertEquals(profile.getCachedClass(), expectedClass);
+        assertThat(profile.isUninitialized(), is(false));
+        assertThat(profile.isGeneric(), is(expectedClass == Object.class));
+        profile.toString(); // test that it is not crashing
+    }
+
+    @Theory
+    public void testProfileThree(Object value0, Object value1, Object value2) {
+        Object result0 = profile.profile(value0);
+        Object result1 = profile.profile(value1);
+        Object result2 = profile.profile(value2);
+
+        assertThat(result0, is(value0));
+        assertThat(result1, is(value1));
+        assertThat(result2, is(value2));
+
+        Object expectedClass = expectedClass(value0) == expectedClass(value1) && expectedClass(value1) == expectedClass(value2) ? expectedClass(value0) : Object.class;
+
+        assertEquals(profile.getCachedClass(), expectedClass);
+        assertThat(profile.isUninitialized(), is(false));
+        assertThat(profile.isGeneric(), is(expectedClass == Object.class));
+        profile.toString(); // test that it is not crashing
+    }
+
+    private static Class<?> expectedClass(Object value) {
+        return value == null ? Object.class : value.getClass();
+    }
+
+}
diff -r 3b3e768a2b92 -r 1e542561783e graal/com.oracle.truffle.api.test/src/com/oracle/truffle/api/test/utilities/IdentityValueProfileTest.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.api.test/src/com/oracle/truffle/api/test/utilities/IdentityValueProfileTest.java	Wed Sep 03 14:58:53 2014 +0200
@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2014, 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.truffle.api.test.utilities;
+
+import static org.hamcrest.CoreMatchers.*;
+import static org.junit.Assert.*;
+
+import org.junit.*;
+import org.junit.experimental.theories.*;
+import org.junit.runner.*;
+
+import com.oracle.truffle.api.utilities.*;
+
+@RunWith(Theories.class)
+public class IdentityValueProfileTest {
+
+    @DataPoint public static final String O1 = new String();
+    @DataPoint public static final String O2 = O1;
+    @DataPoint public static final Object O3 = new Object();
+    @DataPoint public static final Integer O4 = new Integer(1);
+    @DataPoint public static final Integer O5 = null;
+
+    private IdentityValueProfile profile;
+
+    @Before
+    public void create() {
+        profile = (IdentityValueProfile) ValueProfile.createIdentityProfile();
+    }
+
+    @Test
+    public void testInitial() {
+        assertThat(profile.isGeneric(), is(false));
+        assertThat(profile.isUninitialized(), is(true));
+        profile.toString(); // test that it is not crashing
+    }
+
+    @Theory
+    public void testProfileOne(Object value) {
+        Object result = profile.profile(value);
+
+        assertThat(result, is(value));
+        assertEquals(profile.getCachedValue(), value);
+        assertThat(profile.isUninitialized(), is(false));
+        profile.toString(); // test that it is not crashing
+    }
+
+    @Theory
+    public void testProfileTwo(Object value0, Object value1) {
+        Object result0 = profile.profile(value0);
+        Object result1 = profile.profile(value1);
+
+        assertThat(result0, is(value0));
+        assertThat(result1, is(value1));
+
+        if (value0 == value1) {
+            assertThat(profile.getCachedValue(), is(value0));
+            assertThat(profile.isGeneric(), is(false));
+        } else {
+            assertThat(profile.isGeneric(), is(true));
+        }
+        assertThat(profile.isUninitialized(), is(false));
+        profile.toString(); // test that it is not crashing
+    }
+
+    @Theory
+    public void testProfileThree(Object value0, Object value1, Object value2) {
+        Object result0 = profile.profile(value0);
+        Object result1 = profile.profile(value1);
+        Object result2 = profile.profile(value2);
+
+        assertThat(result0, is(value0));
+        assertThat(result1, is(value1));
+        assertThat(result2, is(value2));
+
+        if (value0 == value1 && value1 == value2) {
+            assertThat(profile.getCachedValue(), is(value0));
+            assertThat(profile.isGeneric(), is(false));
+        } else {
+            assertThat(profile.isGeneric(), is(true));
+        }
+        assertThat(profile.isUninitialized(), is(false));
+        profile.toString(); // test that it is not crashing
+    }
+}
diff -r 3b3e768a2b92 -r 1e542561783e graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/ExactClassValueProfile.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/ExactClassValueProfile.java	Wed Sep 03 14:58:53 2014 +0200
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2014, 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.CompilationFinal;
+
+/**
+ * Represents a {@link ValueProfile} that speculates on the exact class of a value.
+ */
+public final class ExactClassValueProfile extends ValueProfile {
+
+    @CompilationFinal protected Class<?> cachedClass;
+
+    ExactClassValueProfile() {
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> T profile(T value) {
+        if (cachedClass != null && cachedClass.isInstance(value)) {
+            return (T) cachedClass.cast(value);
+        } else {
+            CompilerDirectives.transferToInterpreterAndInvalidate();
+            if (cachedClass == null && value != null) {
+                cachedClass = value.getClass();
+            } else {
+                cachedClass = Object.class;
+            }
+        }
+        return value;
+    }
+
+    public boolean isGeneric() {
+        return cachedClass == Object.class;
+    }
+
+    public boolean isUninitialized() {
+        return cachedClass == null;
+    }
+
+    public Class<?> getCachedClass() {
+        return cachedClass;
+    }
+
+    @Override
+    public String toString() {
+        return String.format("%s(%s)@%x", getClass().getSimpleName(), isUninitialized() ? "uninitialized" : (isGeneric() ? "generic" : cachedClass.getName()), hashCode());
+    }
+}
diff -r 3b3e768a2b92 -r 1e542561783e graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/IdentityValueProfile.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/IdentityValueProfile.java	Wed Sep 03 14:58:53 2014 +0200
@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2014, 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 java.util.*;
+
+import com.oracle.truffle.api.*;
+import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
+
+/**
+ * Represents a {@link ValueProfile} that speculates on the object identity of a value.
+ */
+public final class IdentityValueProfile extends ValueProfile {
+
+    private static final Object UNINITIALIZED = new Object();
+    private static final Object GENERIC = new Object();
+
+    @CompilationFinal protected Object cachedValue = UNINITIALIZED;
+
+    IdentityValueProfile() {
+    }
+
+    @Override
+    @SuppressWarnings("unchecked")
+    public <T> T profile(T value) {
+        if (cachedValue != GENERIC) {
+            if (cachedValue == value) {
+                return (T) cachedValue;
+            } else {
+                CompilerDirectives.transferToInterpreterAndInvalidate();
+                if (cachedValue == UNINITIALIZED) {
+                    cachedValue = value;
+                } else {
+                    cachedValue = GENERIC;
+                }
+            }
+        }
+        return value;
+    }
+
+    public boolean isGeneric() {
+        return getCachedValue() == GENERIC;
+    }
+
+    public boolean isUninitialized() {
+        return getCachedValue() == UNINITIALIZED;
+    }
+
+    public Object getCachedValue() {
+        return cachedValue;
+    }
+
+    @Override
+    public String toString() {
+        return String.format("%s(%s)@%x", getClass().getSimpleName(), isUninitialized() ? "uninitialized" : (isGeneric() ? "generic" : String.format("@%x", Objects.hash(cachedValue))), hashCode());
+    }
+
+}
diff -r 3b3e768a2b92 -r 1e542561783e graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/ValueProfile.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/ValueProfile.java	Wed Sep 03 14:58:53 2014 +0200
@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2014, 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;
+
+/**
+ * Utility class to speculate on certain properties of values.
+ *
+ * Example usage:
+ *
+ * <pre>
+ * private final ValueProfile classProfile = ValueProfile.createClassProfile();
+ *
+ * return classProfile.profile(value);
+ * </pre>
+ *
+ * All instances of {@code ValueProfile} (and subclasses) must be held in {@code final} fields for
+ * compiler optimizations to take effect.
+ *
+ * @see #createIdentityProfile()
+ * @see #createClassProfile()
+ */
+public abstract class ValueProfile {
+
+    public abstract <T> T profile(T value);
+
+    /**
+     * Returns a {@link ValueProfile} that speculates on the exact class of a value.
+     */
+    public static ValueProfile createClassProfile() {
+        return new ExactClassValueProfile();
+    }
+
+    /**
+     * Returns a {@link ValueProfile} that speculates on the object identity of a value.
+     */
+    public static ValueProfile createIdentityProfile() {
+        return new IdentityValueProfile();
+    }
+
+}