*** old/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.lir/src/org/graalvm/compiler/lir/alloc/trace/TraceUtil.java	Mon Mar 20 17:39:55 2017
--- new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.lir/src/org/graalvm/compiler/lir/alloc/trace/TraceUtil.java	Mon Mar 20 17:39:55 2017

*** 20,30 ****
--- 20,30 ----
   * 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.Trace;
  import org.graalvm.compiler.core.common.alloc.TraceBuilderResult;
  import org.graalvm.compiler.core.common.cfg.AbstractBlockBase;
  import org.graalvm.compiler.lir.LIR;

*** 61,71 ****
--- 61,71 ----
  
      public static boolean isTrivialTrace(LIR lir, Trace trace) {
          if (trace.size() != 1) {
              return false;
          }
!         ArrayList<LIRInstruction> instructions = lir.getLIRforBlock(trace.getBlocks()[0]);
          if (instructions.size() != 2) {
              return false;
          }
          assert instructions.get(0) instanceof LabelOp : "First instruction not a LabelOp: " + instructions.get(0);
          if (((LabelOp) instructions.get(0)).isPhiIn()) {

*** 84,89 ****
--- 84,113 ----
           * Now we need to check if the BlockEndOp has no special operand requirements (i.e.
           * stack-slot, register). For now we just check for JumpOp because we know that it doesn't.
           */
          return instructions.get(1) instanceof JumpOp;
      }
+ 
+     public static boolean hasInterTracePredecessor(TraceBuilderResult result, Trace trace, AbstractBlockBase<?> block) {
+         assert result.getTraceForBlock(block).equals(trace);
+         if (block.getPredecessorCount() == 0) {
+             // start block
+             return false;
+         }
+         if (block.getPredecessorCount() == 1) {
+             return !result.getTraceForBlock(block.getPredecessors()[0]).equals(trace);
+         }
+         return true;
+     }
+ 
+     public static boolean hasInterTraceSuccessor(TraceBuilderResult result, Trace trace, AbstractBlockBase<?> block) {
+         assert result.getTraceForBlock(block).equals(trace);
+         if (block.getSuccessorCount() == 0) {
+             // method end block
+             return false;
+         }
+         if (block.getSuccessorCount() == 1) {
+             return !result.getTraceForBlock(block.getSuccessors()[0]).equals(trace);
+         }
+         return true;
+     }
  }