BCT/BytecodeTranslator/CLRSemantics.cs


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//-----------------------------------------------------------------------------
//
// Copyright (C) Microsoft Corporation.  All Rights Reserved.
//
//-----------------------------------------------------------------------------
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using Microsoft.Cci;
using Microsoft.Cci.MetadataReader;
using Microsoft.Cci.MutableCodeModel;
using Microsoft.Cci.Contracts;
using Microsoft.Cci.ILToCodeModel;

using Bpl = Microsoft.Boogie;

namespace BytecodeTranslator {

  public class CLRSemantics : TraverserFactory {

    public override ExpressionTraverser MakeExpressionTraverser(Sink sink, StatementTraverser/*?*/ statementTraverser) {
      return new CLRExpressionSemantics(sink, statementTraverser);
    }

    public class CLRExpressionSemantics : ExpressionTraverser {

      public CLRExpressionSemantics(Sink sink, StatementTraverser/*?*/ statementTraverser)
        : base(sink, statementTraverser) { }

      public override void Visit(IDivision division) {
        this.Visit(division.LeftOperand);
        this.Visit(division.RightOperand);
        Bpl.Expr rexp = TranslatedExpressions.Pop();
        Bpl.Expr lexp = TranslatedExpressions.Pop();

        var tok = division.Token();

        var loc = this.sink.CreateFreshLocal(division.RightOperand.Type);
        var locExpr = Bpl.Expr.Ident(loc);
        var storeLocal = Bpl.Cmd.SimpleAssign(tok, locExpr, rexp);
        this.StmtTraverser.StmtBuilder.Add(storeLocal);

        var a = new Bpl.AssertCmd(tok, Bpl.Expr.Binary(Bpl.BinaryOperator.Opcode.Neq, locExpr, Bpl.Expr.Literal(0)));
        this.StmtTraverser.StmtBuilder.Add(a);

        TranslatedExpressions.Push(Bpl.Expr.Binary(Bpl.BinaryOperator.Opcode.Div, lexp, locExpr));
      }
    }
  }
}