--- /dev/null	2016-05-31 09:42:47.975716356 -0700
+++ new/src/jdk.vm.compiler/share/classes/org.graalvm.compiler.lir/src/org/graalvm/compiler/lir/alloc/trace/DefaultTraceRegisterAllocationPolicy.java	2016-12-09 00:54:10.796720808 -0800
@@ -0,0 +1,160 @@
+/*
+ * Copyright (c) 2016, 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 org.graalvm.compiler.lir.alloc.trace;
+
+import java.util.ArrayList;
+
+import org.graalvm.compiler.core.common.alloc.RegisterAllocationConfig;
+import org.graalvm.compiler.core.common.alloc.Trace;
+import org.graalvm.compiler.core.common.alloc.TraceBuilderResult;
+import org.graalvm.compiler.core.common.cfg.AbstractBlockBase;
+import org.graalvm.compiler.lir.alloc.trace.TraceAllocationPhase.TraceAllocationContext;
+import org.graalvm.compiler.lir.alloc.trace.TraceRegisterAllocationPolicy.AllocationStrategy;
+import org.graalvm.compiler.lir.alloc.trace.bu.BottomUpAllocator;
+import org.graalvm.compiler.lir.alloc.trace.lsra.TraceLinearScanPhase;
+import org.graalvm.compiler.lir.gen.LIRGenerationResult;
+import org.graalvm.compiler.lir.gen.LIRGeneratorTool.MoveFactory;
+import org.graalvm.compiler.options.EnumOptionValue;
+import org.graalvm.compiler.options.Option;
+import org.graalvm.compiler.options.OptionType;
+import org.graalvm.compiler.options.StableOptionValue;
+
+import jdk.vm.ci.code.TargetDescription;
+import jdk.vm.ci.common.JVMCIError;
+import jdk.vm.ci.meta.AllocatableValue;
+
+/**
+ * Manages the selection of allocation strategies.
+ */
+public final class DefaultTraceRegisterAllocationPolicy {
+
+    public enum TraceRAPolicies {
+        Default,
+        LinearScanOnly,
+        BottomUpOnly
+    }
+
+    public static class Options {
+        // @formatter:off
+        @Option(help = "Use special allocator for trivial blocks.", type = OptionType.Debug)
+        public static final StableOptionValue<Boolean> TraceRAtrivialBlockAllocator = new StableOptionValue<>(true);
+        @Option(help = "Use LSRA / BottomUp ratio", type = OptionType.Debug)
+        public static final StableOptionValue<Double> TraceRAbottomUpRatio = new StableOptionValue<>(0.0);
+        @Option(help = "TraceRA allocation policy to use.", type = OptionType.Debug)
+        public static final EnumOptionValue<TraceRAPolicies> TraceRAPolicy = new EnumOptionValue<>(TraceRAPolicies.Default);
+        // @formatter:on
+    }
+
+    public static final class TrivialTraceStrategy extends AllocationStrategy {
+
+        public TrivialTraceStrategy(TraceRegisterAllocationPolicy plan) {
+            plan.super();
+        }
+
+        @Override
+        public boolean shouldApplyTo(Trace trace) {
+            return TraceUtil.isTrivialTrace(getLIR(), trace);
+        }
+
+        @Override
+        protected TraceAllocationPhase<TraceAllocationContext> initAllocator(TargetDescription target, LIRGenerationResult lirGenRes, MoveFactory spillMoveFactory,
+                        RegisterAllocationConfig registerAllocationConfig, AllocatableValue[] cachedStackSlots, TraceBuilderResult resultTraces, boolean neverSpillConstant,
+                        ArrayList<AllocationStrategy> strategies) {
+            return new TrivialTraceAllocator();
+        }
+    }
+
+    public static class BottomUpStrategy extends AllocationStrategy {
+
+        public BottomUpStrategy(TraceRegisterAllocationPolicy plan) {
+            // explicitly specify the enclosing instance for the superclass constructor call
+            plan.super();
+        }
+
+        @Override
+        public boolean shouldApplyTo(Trace trace) {
+            return !containsExceptionEdge(trace);
+        }
+
+        private static boolean containsExceptionEdge(Trace trace) {
+            for (AbstractBlockBase<?> block : trace.getBlocks()) {
+                // check if one of the successors is an exception handler
+                for (AbstractBlockBase<?> succ : block.getSuccessors()) {
+                    if (succ.isExceptionEntry()) {
+                        return true;
+                    }
+                }
+            }
+            return false;
+        }
+
+        @Override
+        protected TraceAllocationPhase<TraceAllocationContext> initAllocator(TargetDescription target, LIRGenerationResult lirGenRes, MoveFactory spillMoveFactory,
+                        RegisterAllocationConfig registerAllocationConfig, AllocatableValue[] cachedStackSlots, TraceBuilderResult resultTraces, boolean neverSpillConstant,
+                        ArrayList<AllocationStrategy> strategies) {
+            return new BottomUpAllocator(target, lirGenRes, spillMoveFactory, registerAllocationConfig, cachedStackSlots, resultTraces, neverSpillConstant);
+        }
+    }
+
+    public static final class TraceLinearScanStrategy extends AllocationStrategy {
+
+        public TraceLinearScanStrategy(TraceRegisterAllocationPolicy plan) {
+            // explicitly specify the enclosing instance for the superclass constructor call
+            plan.super();
+        }
+
+        @Override
+        public boolean shouldApplyTo(Trace trace) {
+            return true;
+        }
+
+        @Override
+        protected TraceAllocationPhase<TraceAllocationContext> initAllocator(TargetDescription target, LIRGenerationResult lirGenRes, MoveFactory spillMoveFactory,
+                        RegisterAllocationConfig registerAllocationConfig, AllocatableValue[] cachedStackSlots, TraceBuilderResult resultTraces, boolean neverSpillConstant,
+                        ArrayList<AllocationStrategy> strategies) {
+            return new TraceLinearScanPhase(target, lirGenRes, spillMoveFactory, registerAllocationConfig, resultTraces, neverSpillConstant, cachedStackSlots);
+        }
+    }
+
+    public static TraceRegisterAllocationPolicy allocationPolicy(TargetDescription target, LIRGenerationResult lirGenRes, MoveFactory spillMoveFactory,
+                    RegisterAllocationConfig registerAllocationConfig, AllocatableValue[] cachedStackSlots, TraceBuilderResult resultTraces, boolean neverSpillConstant) {
+        TraceRegisterAllocationPolicy plan = new TraceRegisterAllocationPolicy(target, lirGenRes, spillMoveFactory, registerAllocationConfig, cachedStackSlots, resultTraces, neverSpillConstant);
+        if (Options.TraceRAtrivialBlockAllocator.getValue()) {
+            plan.appendStrategy(new TrivialTraceStrategy(plan));
+        }
+        switch (Options.TraceRAPolicy.getValue()) {
+            case Default:
+            case LinearScanOnly:
+                plan.appendStrategy(new TraceLinearScanStrategy(plan));
+                break;
+            case BottomUpOnly:
+                plan.appendStrategy(new BottomUpStrategy(plan));
+                // Fallback
+                plan.appendStrategy(new TraceLinearScanStrategy(plan));
+                break;
+            default:
+                throw JVMCIError.shouldNotReachHere();
+        }
+        return plan;
+    }
+}