# HG changeset patch
# User Roland Schatz <roland.schatz@oracle.com>
# Date 1362057324 -3600
# Node ID ea1c2bed2bfa5fc783a2b2e41160239607c6cef7
# Parent  0c76156918129f291026b1d8cb0e50ca9344e2da
Common superclass for RegisterValue, StackSlot and Variable.

diff -r 0c7615691812 -r ea1c2bed2bfa graal/com.oracle.graal.api.code/src/com/oracle/graal/api/code/AllocatableValue.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.graal.api.code/src/com/oracle/graal/api/code/AllocatableValue.java	Thu Feb 28 14:15:24 2013 +0100
@@ -0,0 +1,50 @@
+/*
+ * 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.
+ *
+ * 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.graal.api.code;
+
+import com.oracle.graal.api.meta.*;
+
+/**
+ * Common base class for values that can be manipulated by the register allocator.
+ */
+public abstract class AllocatableValue extends Value {
+
+    private static final long serialVersionUID = 153019506717492133L;
+
+    /**
+     * Marker to tell the register allocator that no storage location needs to be allocated for this
+     * value.
+     */
+    @SuppressWarnings("serial") public static final AllocatableValue UNUSED = new AllocatableValue(Kind.Illegal) {
+
+        @Override
+        public String toString() {
+            return "-";
+        }
+    };
+
+    public AllocatableValue(Kind kind) {
+        super(kind);
+    }
+
+}
diff -r 0c7615691812 -r ea1c2bed2bfa graal/com.oracle.graal.api.code/src/com/oracle/graal/api/code/RegisterValue.java
--- a/graal/com.oracle.graal.api.code/src/com/oracle/graal/api/code/RegisterValue.java	Thu Feb 28 14:15:24 2013 +0100
+++ b/graal/com.oracle.graal.api.code/src/com/oracle/graal/api/code/RegisterValue.java	Thu Feb 28 14:15:24 2013 +0100
@@ -30,7 +30,7 @@
  * {@link Register#asValue(Kind)} to retrieve the canonical {@link RegisterValue} instance for a
  * given (register,kind) pair.
  */
-public final class RegisterValue extends Value {
+public final class RegisterValue extends AllocatableValue {
 
     private static final long serialVersionUID = 7999341472196897163L;
 
diff -r 0c7615691812 -r ea1c2bed2bfa graal/com.oracle.graal.api.code/src/com/oracle/graal/api/code/StackSlot.java
--- a/graal/com.oracle.graal.api.code/src/com/oracle/graal/api/code/StackSlot.java	Thu Feb 28 14:15:24 2013 +0100
+++ b/graal/com.oracle.graal.api.code/src/com/oracle/graal/api/code/StackSlot.java	Thu Feb 28 14:15:24 2013 +0100
@@ -30,7 +30,7 @@
  * Represents a compiler spill slot or an outgoing stack-based argument in a method's frame or an
  * incoming stack-based argument in a method's {@linkplain #isInCallerFrame() caller's frame}.
  */
-public final class StackSlot extends Value {
+public final class StackSlot extends AllocatableValue {
 
     private static final long serialVersionUID = -7725071921307318433L;
 
diff -r 0c7615691812 -r ea1c2bed2bfa graal/com.oracle.graal.api.code/src/com/oracle/graal/api/code/ValueUtil.java
--- a/graal/com.oracle.graal.api.code/src/com/oracle/graal/api/code/ValueUtil.java	Thu Feb 28 14:15:24 2013 +0100
+++ b/graal/com.oracle.graal.api.code/src/com/oracle/graal/api/code/ValueUtil.java	Thu Feb 28 14:15:24 2013 +0100
@@ -58,6 +58,16 @@
         return (Constant) value;
     }
 
+    public static boolean isAllocatableValue(Value value) {
+        assert value != null;
+        return value instanceof AllocatableValue;
+    }
+
+    public static AllocatableValue asAllocatableValue(Value value) {
+        assert value != null;
+        return (AllocatableValue) value;
+    }
+
     public static boolean isStackSlot(Value value) {
         assert value != null;
         return value instanceof StackSlot;
diff -r 0c7615691812 -r ea1c2bed2bfa graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/gen/LIRGenerator.java
--- a/graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/gen/LIRGenerator.java	Thu Feb 28 14:15:24 2013 +0100
+++ b/graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/gen/LIRGenerator.java	Thu Feb 28 14:15:24 2013 +0100
@@ -193,6 +193,14 @@
     @Override
     public abstract Variable emitMove(Value input);
 
+    public AllocatableValue asAllocatable(Value value) {
+        if (isAllocatableValue(value)) {
+            return asAllocatableValue(value);
+        } else {
+            return emitMove(value);
+        }
+    }
+
     public Variable load(Value value) {
         if (!isVariable(value)) {
             return emitMove(value);
diff -r 0c7615691812 -r ea1c2bed2bfa graal/com.oracle.graal.lir/src/com/oracle/graal/lir/LIRInstruction.java
--- a/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/LIRInstruction.java	Thu Feb 28 14:15:24 2013 +0100
+++ b/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/LIRInstruction.java	Thu Feb 28 14:15:24 2013 +0100
@@ -181,6 +181,11 @@
         ILLEGAL,
 
         /**
+         * The value can be {@link AllocatableValue#UNUSED}.
+         */
+        UNUSED,
+
+        /**
          * The register allocator should try to assign a certain register to improve code quality.
          * Use {@link LIRInstruction#forEachRegisterHint} to access the register hints.
          */
diff -r 0c7615691812 -r ea1c2bed2bfa graal/com.oracle.graal.lir/src/com/oracle/graal/lir/LIRVerifier.java
--- a/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/LIRVerifier.java	Thu Feb 28 14:15:24 2013 +0100
+++ b/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/LIRVerifier.java	Thu Feb 28 14:15:24 2013 +0100
@@ -232,7 +232,8 @@
 
     private static Value allowed(Object op, Value value, OperandMode mode, EnumSet<OperandFlag> flags) {
         if ((isVariable(value) && flags.contains(OperandFlag.REG)) || (isRegister(value) && flags.contains(OperandFlag.REG)) || (isStackSlot(value) && flags.contains(OperandFlag.STACK)) ||
-                        (isConstant(value) && flags.contains(OperandFlag.CONST) && mode != OperandMode.DEF) || (isIllegal(value) && flags.contains(OperandFlag.ILLEGAL))) {
+                        (isConstant(value) && flags.contains(OperandFlag.CONST) && mode != OperandMode.DEF) || (isIllegal(value) && flags.contains(OperandFlag.ILLEGAL)) ||
+                        (value == AllocatableValue.UNUSED && flags.contains(OperandFlag.UNUSED))) {
             return value;
         }
         TTY.println("instruction %s", op);
diff -r 0c7615691812 -r ea1c2bed2bfa graal/com.oracle.graal.lir/src/com/oracle/graal/lir/Variable.java
--- a/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/Variable.java	Thu Feb 28 14:15:24 2013 +0100
+++ b/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/Variable.java	Thu Feb 28 14:15:24 2013 +0100
@@ -29,7 +29,7 @@
  * Represents a value that is yet to be bound to a machine location (such as a {@link RegisterValue}
  * or {@link StackSlot}) by a register allocator.
  */
-public final class Variable extends Value {
+public final class Variable extends AllocatableValue {
 
     private static final long serialVersionUID = 4507578431686109809L;