--- old/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core.common/src/org/graalvm/compiler/core/common/alloc/BiDirectionalTraceBuilder.java	2017-07-07 09:29:25.000000000 -0700
+++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core.common/src/org/graalvm/compiler/core/common/alloc/BiDirectionalTraceBuilder.java	2017-07-07 09:29:25.000000000 -0700
@@ -31,7 +31,7 @@
 
 import org.graalvm.compiler.core.common.alloc.TraceBuilderResult.TrivialTracePredicate;
 import org.graalvm.compiler.core.common.cfg.AbstractBlockBase;
-import org.graalvm.compiler.debug.Debug;
+import org.graalvm.compiler.debug.DebugContext;
 import org.graalvm.compiler.debug.Indent;
 
 /**
@@ -40,8 +40,8 @@
  */
 public final class BiDirectionalTraceBuilder {
 
-    public static TraceBuilderResult computeTraces(AbstractBlockBase<?> startBlock, AbstractBlockBase<?>[] blocks, TrivialTracePredicate pred) {
-        return new BiDirectionalTraceBuilder(blocks).build(startBlock, blocks, pred);
+    public static TraceBuilderResult computeTraces(DebugContext debug, AbstractBlockBase<?> startBlock, AbstractBlockBase<?>[] blocks, TrivialTracePredicate pred) {
+        return new BiDirectionalTraceBuilder(blocks).build(debug, startBlock, blocks, pred);
     }
 
     private final Deque<AbstractBlockBase<?>> worklist;
@@ -69,22 +69,22 @@
     }
 
     @SuppressWarnings("try")
-    private TraceBuilderResult build(AbstractBlockBase<?> startBlock, AbstractBlockBase<?>[] blocks, TrivialTracePredicate pred) {
-        try (Indent indent = Debug.logAndIndent("BiDirectionalTraceBuilder: start trace building")) {
-            ArrayList<Trace> traces = buildTraces();
+    private TraceBuilderResult build(DebugContext debug, AbstractBlockBase<?> startBlock, AbstractBlockBase<?>[] blocks, TrivialTracePredicate pred) {
+        try (Indent indent = debug.logAndIndent("BiDirectionalTraceBuilder: start trace building")) {
+            ArrayList<Trace> traces = buildTraces(debug);
             assert traces.get(0).getBlocks()[0].equals(startBlock) : "The first traces always contains the start block";
-            return TraceBuilderResult.create(blocks, traces, blockToTrace, pred);
+            return TraceBuilderResult.create(debug, blocks, traces, blockToTrace, pred);
         }
     }
 
-    protected ArrayList<Trace> buildTraces() {
+    protected ArrayList<Trace> buildTraces(DebugContext debug) {
         ArrayList<Trace> traces = new ArrayList<>();
         // process worklist
         while (!worklist.isEmpty()) {
             AbstractBlockBase<?> block = worklist.pollFirst();
             assert block != null;
             if (!processed(block)) {
-                Trace trace = new Trace(startTrace(block));
+                Trace trace = new Trace(startTrace(debug, block));
                 for (AbstractBlockBase<?> traceBlock : trace.getBlocks()) {
                     blockToTrace[traceBlock.getId()] = trace;
                 }
@@ -97,14 +97,16 @@
 
     /**
      * Build a new trace starting at {@code block}.
+     *
+     * @param debug
      */
     @SuppressWarnings("try")
-    private Collection<AbstractBlockBase<?>> startTrace(AbstractBlockBase<?> block) {
+    private Collection<AbstractBlockBase<?>> startTrace(DebugContext debug, AbstractBlockBase<?> block) {
         ArrayDeque<AbstractBlockBase<?>> trace = new ArrayDeque<>();
-        try (Indent i = Debug.logAndIndent("StartTrace: %s", block)) {
-            try (Indent indentFront = Debug.logAndIndent("Head:")) {
+        try (Indent i = debug.logAndIndent("StartTrace: %s", block)) {
+            try (Indent indentFront = debug.logAndIndent("Head:")) {
                 for (AbstractBlockBase<?> currentBlock = block; currentBlock != null; currentBlock = selectPredecessor(currentBlock)) {
-                    addBlockToTrace(currentBlock);
+                    addBlockToTrace(debug, currentBlock);
                     trace.addFirst(currentBlock);
                 }
             }
@@ -114,21 +116,21 @@
                 b.setLinearScanNumber(blockNr++);
             }
 
-            try (Indent indentBack = Debug.logAndIndent("Tail:")) {
+            try (Indent indentBack = debug.logAndIndent("Tail:")) {
                 for (AbstractBlockBase<?> currentBlock = selectSuccessor(block); currentBlock != null; currentBlock = selectSuccessor(currentBlock)) {
-                    addBlockToTrace(currentBlock);
+                    addBlockToTrace(debug, currentBlock);
                     trace.addLast(currentBlock);
                     /* This time we can number the blocks immediately as we go forwards. */
                     currentBlock.setLinearScanNumber(blockNr++);
                 }
             }
         }
-        Debug.log("Trace: %s", trace);
+        debug.log("Trace: %s", trace);
         return trace;
     }
 
-    private void addBlockToTrace(AbstractBlockBase<?> currentBlock) {
-        Debug.log("add %s (prob: %f)", currentBlock, currentBlock.probability());
+    private void addBlockToTrace(DebugContext debug, AbstractBlockBase<?> currentBlock) {
+        debug.log("add %s (prob: %f)", currentBlock, currentBlock.probability());
         processed.set(currentBlock.getId());
     }