Fixed issue with uniformity analysis and block merging. Uniformity analysis

now enabled by default.

1 files changed, 8 insertions, 3 deletions

diff --git a/Source/VCGeneration/VC.cs b/Source/VCGeneration/VC.cs
index 2ac8dc83..e7f5999a 100644
--- a/Source/VCGeneration/VC.cs
+++ b/Source/VCGeneration/VC.cs
@@ -3042,15 +3042,20 @@ namespace VC {
     /// <summary>

     /// Simplifies the CFG of the given implementation impl by merging each

     /// basic block with a single predecessor into that predecessor if the

-    /// predecessor has a single successor.

+    /// predecessor has a single successor.  If a uniformity analyser is

+    /// being used then block will only be merged if they are both uniform

+    /// or both non-uniform

     /// </summary>

-    public static void MergeBlocksIntoPredecessors(Program prog, Implementation impl) {

+    public static void MergeBlocksIntoPredecessors(Program prog, Implementation impl, UniformityAnalyser uni) {

       var blockGraph = prog.ProcessLoops(impl);

       var predMap = new Dictionary<Block, Block>();

       foreach (var block in blockGraph.Nodes) {

         try {

           var pred = blockGraph.Predecessors(block).Single();

-          if (blockGraph.Successors(pred).Single() == block) {

+          if (blockGraph.Successors(pred).Single() == block &&

+              (uni == null || 

+              (uni.IsUniform(impl.Name, pred) && uni.IsUniform(impl.Name, block)) ||

+              (!uni.IsUniform(impl.Name, pred) && !uni.IsUniform(impl.Name, block)))) {

             Block predMapping;

             while (predMap.TryGetValue(pred, out predMapping))

               pred = predMapping;