Improve support for optimization and identifying unnecessary assumes.

3 files changed, 18 insertions, 18 deletions

diff --git a/Source/VCGeneration/Check.cs b/Source/VCGeneration/Check.cs
index 8c1ae407..ae4d158a 100644
--- a/Source/VCGeneration/Check.cs
+++ b/Source/VCGeneration/Check.cs
@@ -346,7 +346,7 @@ namespace Microsoft.Boogie {
       }
     }
 
-    public void BeginCheck(string descriptiveName, VCExpr vc, ProverInterface.ErrorHandler handler, IList<VCExprVar> namedAssumeVars = null) {
+    public void BeginCheck(string descriptiveName, VCExpr vc, ProverInterface.ErrorHandler handler) {
       Contract.Requires(descriptiveName != null);
       Contract.Requires(vc != null);
       Contract.Requires(handler != null);
@@ -360,7 +360,6 @@ namespace Microsoft.Boogie {
       thmProver.Reset(gen);
       SetTimeout();
       proverStart = DateTime.UtcNow;
-      thmProver.NamedAssumeVars = namedAssumeVars;
       thmProver.BeginCheck(descriptiveName, vc, handler);
       //  gen.ClearSharedFormulas();    PR: don't know yet what to do with this guy
 
@@ -388,8 +387,6 @@ namespace Microsoft.Boogie {
 
   public abstract class ProverInterface {
 
-    public IList<VCExprVar> NamedAssumeVars;
-
     public static ProverInterface CreateProver(Program prog, string/*?*/ logFilePath, bool appendLogFile, int timeout, int taskID = -1) {
       Contract.Requires(prog != null);
 
@@ -546,7 +543,7 @@ namespace Microsoft.Boogie {
     }
 
     // (assert vc)
-    public virtual void Assert(VCExpr vc, bool polarity)
+    public virtual void Assert(VCExpr vc, bool polarity, bool isSoft = false, int weight = 1)
     {
         throw new NotImplementedException();
     }
diff --git a/Source/VCGeneration/VC.cs b/Source/VCGeneration/VC.cs
index ad067c04..6e43e917 100644
--- a/Source/VCGeneration/VC.cs
+++ b/Source/VCGeneration/VC.cs
@@ -1386,8 +1386,7 @@ namespace VC {
         var exprGen = ctx.ExprGen;
         VCExpr controlFlowVariableExpr = CommandLineOptions.Clo.UseLabels ? null : exprGen.Integer(BigNum.ZERO);
 
-        var namedAssumeVars = new List<VCExprVar>();
-        VCExpr vc = parent.GenerateVCAux(impl, controlFlowVariableExpr, label2absy, checker.TheoremProver.Context, namedAssumeVars: namedAssumeVars);
+        VCExpr vc = parent.GenerateVCAux(impl, controlFlowVariableExpr, label2absy, checker.TheoremProver.Context);
         Contract.Assert(vc != null);
 
         if (!CommandLineOptions.Clo.UseLabels)
@@ -1415,7 +1414,7 @@ namespace VC {
         string desc = cce.NonNull(impl.Name);
         if (no >= 0)
           desc += "_split" + no;
-        checker.BeginCheck(desc, vc, reporter, namedAssumeVars);
+        checker.BeginCheck(desc, vc, reporter);
       }
 
       private void SoundnessCheck(HashSet<List<Block>/*!*/>/*!*/ cache, Block/*!*/ orig, List<Block/*!*/>/*!*/ copies) {
@@ -1568,8 +1567,7 @@ namespace VC {
           }
           break;
         case CommandLineOptions.VCVariety.DagIterative:
-          // TODO(wuestholz): Support named assume statements not just for this encoding.
-          vc = LetVCIterative(impl.Blocks, controlFlowVariableExpr, label2absy, proverContext, out assertionCount, namedAssumeVars: namedAssumeVars);
+          vc = LetVCIterative(impl.Blocks, controlFlowVariableExpr, label2absy, proverContext, out assertionCount);
           break;
         case CommandLineOptions.VCVariety.Doomed:
           vc = FlatBlockVC(impl, label2absy, false, false, true, proverContext, out assertionCount);
@@ -3393,7 +3391,7 @@ namespace VC {
                                  Dictionary<int, Absy> label2absy,
                                  ProverContext proverCtxt,
                                  out int assertionCount,
-                                 bool isPositiveContext = true, IList<VCExprVar> namedAssumeVars = null)
+                                 bool isPositiveContext = true)
     {
       Contract.Requires(blocks != null);
       Contract.Requires(proverCtxt != null);
@@ -3453,7 +3451,7 @@ namespace VC {
         }
 
         VCContext context = new VCContext(label2absy, proverCtxt, controlFlowVariableExpr, isPositiveContext);
-        VCExpr vc = Wlp.Block(block, SuccCorrect, context, namedAssumeVars);
+        VCExpr vc = Wlp.Block(block, SuccCorrect, context);
         assertionCount += context.AssertionCount;
 
         VCExprVar v = gen.Variable(block.Label + "_correct", Bpl.Type.Bool);
diff --git a/Source/VCGeneration/Wlp.cs b/Source/VCGeneration/Wlp.cs
index 508a1400..07db709d 100644
--- a/Source/VCGeneration/Wlp.cs
+++ b/Source/VCGeneration/Wlp.cs
@@ -48,7 +48,7 @@ namespace VC {
   
   public class Wlp
   {
-    public static VCExpr Block(Block b, VCExpr N, VCContext ctxt, IList<VCExprVar> namedAssumeVars = null)
+    public static VCExpr Block(Block b, VCExpr N, VCContext ctxt)
       //modifies ctxt.*;
     {
       Contract.Requires(b != null);
@@ -63,7 +63,7 @@ namespace VC {
 
       for (int i = b.Cmds.Count; --i >= 0; )
       {
-        res = Cmd(b, cce.NonNull( b.Cmds[i]), res, ctxt, namedAssumeVars);
+        res = Cmd(b, cce.NonNull( b.Cmds[i]), res, ctxt);
       }
       
       int id = b.UniqueId;
@@ -87,7 +87,7 @@ namespace VC {
     /// <summary>
     /// Computes the wlp for an assert or assume command "cmd".
     /// </summary>
-    internal static VCExpr Cmd(Block b, Cmd cmd, VCExpr N, VCContext ctxt, IList<VCExprVar> namedAssumeVars = null) {
+    internal static VCExpr Cmd(Block b, Cmd cmd, VCExpr N, VCContext ctxt) {
       Contract.Requires(cmd != null);
       Contract.Requires(N != null);
       Contract.Requires(ctxt != null);
@@ -193,11 +193,16 @@ namespace VC {
         var expr = ctxt.Ctxt.BoogieExprTranslator.Translate(ac.Expr);
         
         var aid = QKeyValue.FindStringAttribute(ac.Attributes, "id");
-        if (CommandLineOptions.Clo.PrintNecessaryAssumes && aid != null && namedAssumeVars != null)
+        if (CommandLineOptions.Clo.PrintNecessaryAssumes && aid != null)
         {
           var v = gen.Variable("assume$$" + aid, Microsoft.Boogie.Type.Bool);
-          namedAssumeVars.Add(v);
-          expr = gen.ImpliesSimp(v, expr);
+          expr = gen.Function(VCExpressionGenerator.NamedAssumeOp, v, gen.ImpliesSimp(v, expr));
+        }
+        var soft = QKeyValue.FindBoolAttribute(ac.Attributes, "soft");
+        if (soft && aid != null)
+        {
+          var v = gen.Variable("soft$$" + aid, Microsoft.Boogie.Type.Bool);
+          expr = gen.Function(VCExpressionGenerator.SoftOp, v, gen.ImpliesSimp(v, expr));
         }
         return MaybeWrapWithOptimization(ctxt, gen, ac.Attributes, gen.ImpliesSimp(expr, N));
       } else {