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|
//-----------------------------------------------------------------------------
//
// Copyright (C) Microsoft Corporation. All Rights Reserved.
//
//-----------------------------------------------------------------------------
using System;
using System.Text;
using System.IO;
using System.Collections;
using System.Collections.Generic;
using Microsoft.Contracts;
using Microsoft.Basetypes;
// A translator from the Boogie AST to the VCExpr AST.
// This was previously realised in the methods AbsyExpr.VCView
namespace Microsoft.Boogie.VCExprAST
{
using Microsoft.Boogie;
public class VCGenerationOptions {
private readonly List<string!>! SupportedProverCommands;
public bool IsProverCommandSupported(string! kind)
{
return SupportedProverCommands.Contains(kind);
}
public bool IsAnyProverCommandSupported(string! kinds)
{
if (kinds.IndexOf(',') < 0) {
return IsProverCommandSupported(kinds);
} else {
return exists{string k in kinds.Split(',', ' '); IsProverCommandSupported(k)};
}
}
public VCGenerationOptions(List<string!>! supportedProverCommands) {
this.SupportedProverCommands = supportedProverCommands;
}
}
public delegate VCExpr! CodeExprConverter(CodeExpr! codeExpr, Hashtable/*<Block, VCExprVar!>*/! blockVariables, List<VCExprLetBinding!>! bindings);
public class Boogie2VCExprTranslator : StandardVisitor, ICloneable {
// Stack on which the various Visit-methods put the result of the translation
private readonly Stack<VCExpr!>! SubExpressions = new Stack<VCExpr!> ();
private void Push(VCExpr! expr) {
SubExpressions.Push(expr);
}
private VCExpr! Pop() {
return SubExpressions.Pop();
}
public VCExpr! Translate(Expr! expr) {
this.Visit(expr);
return Pop();
}
public List<VCExpr!>! Translate(ExprSeq! exprs) {
List<VCExpr!>! res = new List<VCExpr!> ();
foreach(Expr e in exprs)
res.Add(Translate((!)e));
return res;
}
///////////////////////////////////////////////////////////////////////////////
internal readonly VCExpressionGenerator! Gen;
public Boogie2VCExprTranslator(VCExpressionGenerator! gen,
VCGenerationOptions! genOptions) {
this.Gen = gen;
this.GenerationOptions = genOptions;
UnboundVariables = new VariableMapping<Variable> ();
BoundVariables = new VariableMapping<BoundVariable> ();
Formals = new VariableMapping<Formal> ();
}
private Boogie2VCExprTranslator(Boogie2VCExprTranslator! tl) {
this.Gen = tl.Gen;
this.GenerationOptions = tl.GenerationOptions;
UnboundVariables =
(VariableMapping<Variable>)tl.UnboundVariables.Clone();
BoundVariables = new VariableMapping<BoundVariable> ();
Formals = new VariableMapping<Formal> ();
}
public object! Clone() {
return new Boogie2VCExprTranslator(this);
}
private IAppliableTranslator IAppTranslatorAttr = null;
private IAppliableTranslator! IAppTranslator { get {
if (IAppTranslatorAttr == null)
IAppTranslatorAttr = new IAppliableTranslator (this);
return IAppTranslatorAttr;
} }
///////////////////////////////////////////////////////////////////////////////
// Class for handling occurring variables
private class VariableMapping<VarKind> : ICloneable {
private readonly List<Dictionary<VarKind!, VCExprVar!>!>! Mapping;
public VariableMapping() {
List<Dictionary<VarKind!, VCExprVar!>!>! mapping =
new List<Dictionary<VarKind!, VCExprVar!>!> ();
mapping.Add(new Dictionary<VarKind!, VCExprVar!> ());
this.Mapping = mapping;
}
private VariableMapping(VariableMapping<VarKind>! vm) {
List<Dictionary<VarKind!, VCExprVar!>!>! mapping =
new List<Dictionary<VarKind!, VCExprVar!>!> ();
foreach (Dictionary<VarKind!, VCExprVar!>! d in vm.Mapping)
mapping.Add(new Dictionary<VarKind!, VCExprVar!> (d));
this.Mapping = mapping;
}
public object! Clone() {
return new VariableMapping<VarKind> (this);
}
public void PushScope() {
Mapping.Add(new Dictionary<VarKind!, VCExprVar!> ());
}
public void PopScope() {
assume Mapping.Count > 0;
Mapping.RemoveAt(Mapping.Count - 1);
}
public void Bind(VarKind! boogieVar, VCExprVar! vcExprVar)
requires !Contains(boogieVar); {
Mapping[Mapping.Count - 1].Add(boogieVar, vcExprVar);
}
public VCExprVar! Lookup(VarKind! boogieVar) {
VCExprVar res = LookupHelp(boogieVar);
assume res != null;
return res;
}
[Pure]
public bool Contains(VarKind! boogieVar) {
return LookupHelp(boogieVar) != null;
}
public bool TryGetValue(VarKind! boogieVar, out VCExprVar res) {
res = LookupHelp(boogieVar);
return res != null;
}
[Pure]
private VCExprVar LookupHelp(VarKind! boogieVar) {
VCExprVar res;
foreach (Dictionary<VarKind!, VCExprVar!>! d in Mapping) {
if (d.TryGetValue(boogieVar, out res))
return res;
}
return null;
}
}
//////////////////////////////////////////////////////////////////////////////////
private readonly VariableMapping<Variable>! UnboundVariables;
private readonly VariableMapping<BoundVariable>! BoundVariables;
// used when translating the bodies of function expansions
private readonly VariableMapping<Formal>! Formals;
internal void PushBoundVariableScope() {
BoundVariables.PushScope();
}
internal void PopBoundVariableScope() {
BoundVariables.PopScope();
}
internal void PushFormalsScope() {
Formals.PushScope();
}
internal void PopFormalsScope() {
Formals.PopScope();
}
public VCExprVar! BindVariable(Variable! boogieVar) {
if (boogieVar is BoundVariable) {
VCExprVar! newVar = Gen.Variable(boogieVar.Name, boogieVar.TypedIdent.Type);
BoundVariables.Bind((BoundVariable)boogieVar, newVar);
return newVar;
} else if (boogieVar is Formal) {
VCExprVar! newVar = Gen.Variable(boogieVar.Name, boogieVar.TypedIdent.Type);
Formals.Bind((Formal)boogieVar, newVar);
return newVar;
} else {
// only bound variables and formals are declared explicitly
assert false;
}
}
public VCExprVar! LookupVariable(Variable! boogieVar) {
BoundVariable bv = boogieVar as BoundVariable;
if (bv != null) {
return BoundVariables.Lookup(bv);
}
VCExprVar res;
Formal fml = boogieVar as Formal;
if (fml != null && Formals.TryGetValue(fml, out res))
return (!)res;
// global variables, local variables, incarnations, etc. are
// bound the first time they occur
if (!UnboundVariables.TryGetValue(boogieVar, out res)) {
res = new VCExprVar (boogieVar.Name, boogieVar.TypedIdent.Type);
UnboundVariables.Bind(boogieVar, res);
}
return (!)res;
}
///////////////////////////////////////////////////////////////////////////////////
internal readonly VCGenerationOptions! GenerationOptions;
///////////////////////////////////////////////////////////////////////////////////
public override LiteralExpr! VisitLiteralExpr(LiteralExpr! node) {
Push(TranslateLiteralExpr(node));
return node;
}
private VCExpr! TranslateLiteralExpr(LiteralExpr! node) {
if ( node.Val is bool )
{
bool b = (bool) node.Val;
if ( b ) {
return VCExpressionGenerator.True;
} else {
return VCExpressionGenerator.False;
}
}
else if ( node.Val is BigNum )
{
return Gen.Integer(node.asBigNum);
}
else if ( node.Val is BvConst )
{
return Gen.Bitvector((BvConst)node.Val);
}
else
{
System.Diagnostics.Debug.Assert(false, "unknown kind of literal " + node.tok.ToString());
assert false;
}
}
///////////////////////////////////////////////////////////////////////////////////
public override AIVariableExpr! VisitAIVariableExpr(AIVariableExpr! node)
{
assert false;
}
///////////////////////////////////////////////////////////////////////////////////
public override Expr! VisitIdentifierExpr(IdentifierExpr! node) {
assume node.Decl != null; // the expression has to be resolved
Push(LookupVariable(node.Decl));
return node;
}
///////////////////////////////////////////////////////////////////////////////////
// Because of our scheme for numbering incarnations of variables, the pre-state
// value of a variable x is always just "x". (The first update to it in a method
// causes it to become "x0". So we just remove old expressions with a visitor
// before transforming it into a VCExpr.
public override Expr! VisitOldExpr(OldExpr! node)
{
assert false;
}
///////////////////////////////////////////////////////////////////////////////////
public override Expr! VisitNAryExpr(NAryExpr! node)
{
Push(TranslateNAryExpr(node));
return node;
}
private VCExpr! TranslateNAryExpr(NAryExpr! node) {
int n = node.Args.Length;
List<VCExpr!>! vcs = new List<VCExpr!> (n);
for(int i = 0; i < n; i++)
{
vcs.Add(Translate((!)node.Args[i]));
}
if (node.Type == null) {
System.Console.WriteLine("*** type is null for {0}", node);
assert false;
}
return IAppTranslator.Translate(node.Fun, node.Type, vcs,
ToList((!)node.TypeParameters));
}
private static List<Type!>! EMPTY_TYPE_LIST = new List<Type!> ();
private List<Type!>! ToList(TypeParamInstantiation! insts) {
if (insts.FormalTypeParams.Count == 0)
return EMPTY_TYPE_LIST;
List<Type!>! typeArgs = new List<Type!> ();
foreach (TypeVariable! var in insts.FormalTypeParams)
typeArgs.Add(insts[var]);
return typeArgs;
}
///////////////////////////////////////////////////////////////////////////////////
public override QuantifierExpr! VisitQuantifierExpr(QuantifierExpr! node) {
Push(TranslateQuantifierExpr(node));
return node;
}
public override ExistsExpr! VisitExistsExpr(ExistsExpr! node)
{
node = (ExistsExpr) this.VisitQuantifierExpr(node);
return node;
}
public override ForallExpr! VisitForallExpr(ForallExpr! node)
{
node = (ForallExpr) this.VisitQuantifierExpr(node);
return node;
}
private VCExpr! TranslateQuantifierExpr(QuantifierExpr! node)
{
List<TypeVariable!>! typeParams = new List<TypeVariable!> ();
foreach (TypeVariable! v in node.TypeParameters)
typeParams.Add(v);
PushBoundVariableScope();
List<VCExprVar!>! boundVars = new List<VCExprVar!> ();
foreach (Variable! v in node.Dummies)
boundVars.Add(BindVariable(v));
try {
List<VCTrigger!>! triggers = TranslateTriggers(node.Triggers);
VCExpr! body = Translate(node.Body);
VCQuantifierInfos! infos = GenerateQuantifierInfos(node);
Quantifier quan;
if (node is ForallExpr)
quan = Quantifier.ALL;
else if (node is ExistsExpr)
quan = Quantifier.EX;
else
assert false;
return Gen.Quantify(quan, typeParams, boundVars, triggers, infos, body);
} finally {
PopBoundVariableScope();
}
}
private List<VCTrigger!>! TranslateTriggers(Trigger node)
{
List<VCTrigger!>! res = new List<VCTrigger!> ();
Trigger curTrigger = node;
while (curTrigger != null) {
res.Add(Gen.Trigger(curTrigger.Pos, Translate(curTrigger.Tr)));
curTrigger = curTrigger.Next;
}
return res;
}
private VCQuantifierInfos! GenerateQuantifierInfos(QuantifierExpr! node) {
string qid = getQidNameFromQKeyValue(node.Dummies, node.Attributes);
return new VCQuantifierInfos(qid, node.SkolemId, false, node.Attributes);
}
private string getQidNameFromQKeyValue(VariableSeq! vars, QKeyValue attributes) {
// Check for a 'qid, name' pair in keyvalues
string qid = QKeyValue.FindStringAttribute(attributes, "qid");
if (qid == null && vars.Length != 0){
// generate default name (line:column position in .bpl file)
Variable v = vars[0];
assert v != null; // Rustan's claim!
// Include the first 8 characters of the filename in QID (helpful in case we use /concat)
// We limit it to 8, so the SX file doesn't grow too big, and who on earth would need
// more than 8 characters in a filename anyways.
int max = 8;
StringBuilder buf = new StringBuilder(max + 20);
string filename = v.tok.filename;
if (filename == null) filename = "unknown";
for (int i = 0; i < filename.Length; ++i) {
if (filename[i] == '/' || filename[i] == '\\') buf.Length = 0;
if (buf.Length < max && char.IsLetterOrDigit(filename[i])) {
if (buf.Length == 0 && char.IsDigit(filename[i])) {
// Z3 does not like QID's to start with a digit, so we prepend another character
buf.Append('_');
}
buf.Append(filename[i]);
}
}
buf.Append('.').Append(v.Line).Append(':').Append(v.Col);
qid = buf.ToString();
}
return qid;
}
///////////////////////////////////////////////////////////////////////////////////
public override BvExtractExpr! VisitBvExtractExpr(BvExtractExpr! node)
{
Push(TranslateBvExtractExpr(node));
return node;
}
private VCExpr! TranslateBvExtractExpr(BvExtractExpr! node)
requires node.Start <= node.End; {
VCExpr! bv = Translate(node.Bitvector);
return Gen.BvExtract(bv, ((!)node.Bitvector.Type).BvBits, node.Start, node.End);
}
///////////////////////////////////////////////////////////////////////////////////
public override BvConcatExpr! VisitBvConcatExpr(BvConcatExpr! node)
{
Push(TranslateBvConcatExpr(node));
return node;
}
private VCExpr! TranslateBvConcatExpr(BvConcatExpr! node) {
VCExpr! bv0 = Translate(node.E0);
VCExpr! bv1 = Translate(node.E1);
return Gen.BvConcat(bv0, bv1);
}
///////////////////////////////////////////////////////////////////////////////////
// all the other cases should never happen
public override Cmd! VisitAssertCmd(AssertCmd! node)
{
assert false;
}
public override Cmd! VisitAssignCmd(AssignCmd! node)
{
assert false;
}
public override Cmd! VisitAssumeCmd(AssumeCmd! node)
{
assert false;
}
public override AtomicRE! VisitAtomicRE(AtomicRE! node)
{
assert false;
}
public override Axiom! VisitAxiom(Axiom! node)
{
assert false;
}
public override Type! VisitBasicType(BasicType! node)
{
assert false;
}
public override Type! VisitBvType(BvType! node)
{
assert false;
}
public override Block! VisitBlock(Block! node)
{
assert false;
}
CodeExprConverter codeExprConverter = null;
public void SetCodeExprConverter(CodeExprConverter f){
this.codeExprConverter = f;
}
public override Expr! VisitCodeExpr(CodeExpr! codeExpr)
{
assume codeExprConverter != null;
Hashtable/*<Block, LetVariable!>*/ blockVariables = new Hashtable/*<Block, LetVariable!!>*/();
List<VCExprLetBinding!> bindings = new List<VCExprLetBinding!>();
VCExpr e = codeExprConverter(codeExpr, blockVariables, bindings);
Push(e);
return codeExpr;
}
public override BlockSeq! VisitBlockSeq(BlockSeq! blockSeq)
{
assert false;
}
public override List<Block!>! VisitBlockList(List<Block!>! blocks)
{
assert false;
}
public override BoundVariable! VisitBoundVariable(BoundVariable! node)
{
assert false;
}
public override Cmd! VisitCallCmd(CallCmd! node)
{
assert false;
}
public override Cmd! VisitCallForallCmd(CallForallCmd! node)
{
assert false;
}
public override CmdSeq! VisitCmdSeq(CmdSeq! cmdSeq)
{
assert false;
}
public override Choice! VisitChoice(Choice! node)
{
assert false;
}
public override Cmd! VisitCommentCmd(CommentCmd! node)
{
assert false;
}
public override Constant! VisitConstant(Constant! node)
{
assert false;
}
public override CtorType! VisitCtorType(CtorType! node)
{
assert false;
}
public override Declaration! VisitDeclaration(Declaration! node)
{
assert false;
}
public override List<Declaration!>! VisitDeclarationList(List<Declaration!>! declarationList)
{
assert false;
}
public override DeclWithFormals! VisitDeclWithFormals(DeclWithFormals! node)
{
assert false;
}
public override Requires! VisitRequires(Requires! @requires)
{
assert false;
}
public override RequiresSeq! VisitRequiresSeq(RequiresSeq! requiresSeq)
{
assert false;
}
public override Ensures! VisitEnsures(Ensures! @ensures)
{
assert false;
}
public override EnsuresSeq! VisitEnsuresSeq(EnsuresSeq! ensuresSeq)
{
assert false;
}
public override Formal! VisitFormal(Formal! node)
{
assert false;
}
public override Function! VisitFunction(Function! node)
{
assert false;
}
public override GlobalVariable! VisitGlobalVariable(GlobalVariable! node)
{
assert false;
}
public override GotoCmd! VisitGotoCmd(GotoCmd! node)
{
assert false;
}
public override Cmd! VisitHavocCmd(HavocCmd! node)
{
assert false;
}
public override Implementation! VisitImplementation(Implementation! node)
{
assert false;
}
public override LocalVariable! VisitLocalVariable(LocalVariable! node)
{
assert false;
}
public override AssignLhs! VisitMapAssignLhs(MapAssignLhs! node)
{
assert false;
}
public override MapType! VisitMapType(MapType! node)
{
assert false;
}
public override Procedure! VisitProcedure(Procedure! node)
{
assert false;
}
public override Program! VisitProgram(Program! node)
{
assert false;
}
public override Cmd! VisitRE(RE! node)
{
assert false;
}
public override RESeq! VisitRESeq(RESeq! reSeq)
{
assert false;
}
public override ReturnCmd! VisitReturnCmd(ReturnCmd! node)
{
assert false;
}
public override ReturnExprCmd! VisitReturnExprCmd(ReturnExprCmd! node)
{
assert false;
}
public override Sequential! VisitSequential(Sequential! node)
{
assert false;
}
public override AssignLhs! VisitSimpleAssignLhs(SimpleAssignLhs! node)
{
assert false;
}
public override Cmd! VisitStateCmd(StateCmd! node)
{
assert false;
}
public override TransferCmd! VisitTransferCmd(TransferCmd! node)
{
assert false;
}
public override Trigger! VisitTrigger(Trigger! node)
{
assert false;
}
public override Type! VisitType(Type! node)
{
assert false;
}
public override TypedIdent! VisitTypedIdent(TypedIdent! node)
{
assert false;
}
public override Type! VisitTypeSynonymAnnotation(TypeSynonymAnnotation! node)
{
assert false;
}
public override Type! VisitTypeVariable(TypeVariable! node)
{
assert false;
}
public override Variable! VisitVariable(Variable! node)
{
assert false;
}
public override VariableSeq! VisitVariableSeq(VariableSeq! variableSeq)
{
assert false;
}
public override Cmd! VisitAssertEnsuresCmd(AssertEnsuresCmd! node)
{
assert false;
}
public override Cmd! VisitAssertRequiresCmd(AssertRequiresCmd! node)
{
assert false;
}
}
/////////////////////////////////////////////////////////////////////////////////
public class IAppliableTranslator : IAppliableVisitor<VCExpr!> {
private readonly Boogie2VCExprTranslator! BaseTranslator;
private VCExpressionGenerator! Gen { get {
return BaseTranslator.Gen;
} }
private VCGenerationOptions! GenerationOptions { get {
return BaseTranslator.GenerationOptions;
} }
public IAppliableTranslator(Boogie2VCExprTranslator! baseTranslator) {
this.BaseTranslator = baseTranslator;
}
///////////////////////////////////////////////////////////////////////////////
private List<VCExpr!>! args = new List<VCExpr!>();
private List<Type!>! typeArgs = new List<Type!>();
public VCExpr! Translate(IAppliable! app, Type! ty, List<VCExpr!>! args, List<Type!>! typeArgs) {
List<VCExpr!>! oldArgs = this.args;
List<Type!>! oldTypeArgs = this.typeArgs;
this.args = args;
this.typeArgs = typeArgs;
VCExpr! result = app.Dispatch<VCExpr!>(this);
this.args = oldArgs;
this.typeArgs = oldTypeArgs;
return result;
}
///////////////////////////////////////////////////////////////////////////////
public VCExpr! Visit(UnaryOperator! unaryOperator) {
assert unaryOperator.Op == UnaryOperator.Opcode.Not && this.args.Count == 1;
return Gen.Not(this.args);
}
public VCExpr! Visit(BinaryOperator! binaryOperator) {
return TranslateBinaryOperator(binaryOperator, this.args);
}
public VCExpr! Visit(FunctionCall! functionCall) {
return TranslateFunctionCall(functionCall, this.args, this.typeArgs);
}
public VCExpr! Visit(MapSelect! mapSelect) {
return Gen.Select(this.args, this.typeArgs);
}
public VCExpr! Visit(MapStore! mapStore) {
return Gen.Store(this.args, this.typeArgs);
}
public VCExpr! Visit(TypeCoercion! typeCoercion) {
assert this.args.Count == 1;
return this.args[0];
}
public VCExpr! Visit(IfThenElse! ite) {
return Gen.Function(VCExpressionGenerator.IfThenElseOp, this.args);
}
///////////////////////////////////////////////////////////////////////////////
private VCExpr! TranslateBinaryOperator(BinaryOperator! app, List<VCExpr!>! args) {
assert args.Count == 2;
switch (app.Op) {
case BinaryOperator.Opcode.Add:
return Gen.Function(VCExpressionGenerator.AddOp, args);
case BinaryOperator.Opcode.Sub:
return Gen.Function(VCExpressionGenerator.SubOp, args);
case BinaryOperator.Opcode.Mul:
return Gen.Function(VCExpressionGenerator.MulOp, args);
case BinaryOperator.Opcode.Div:
return Gen.Function(VCExpressionGenerator.DivOp, args);
case BinaryOperator.Opcode.Mod:
return Gen.Function(VCExpressionGenerator.ModOp, args);
case BinaryOperator.Opcode.Eq:
case BinaryOperator.Opcode.Iff:
// we don't distinguish between equality and equivalence at this point
return Gen.Function(VCExpressionGenerator.EqOp, args);
case BinaryOperator.Opcode.Neq:
return Gen.Function(VCExpressionGenerator.NeqOp, args);
case BinaryOperator.Opcode.Lt:
return Gen.Function(VCExpressionGenerator.LtOp, args);
case BinaryOperator.Opcode.Le:
return Gen.Function(VCExpressionGenerator.LeOp, args);
case BinaryOperator.Opcode.Ge:
return Gen.Function(VCExpressionGenerator.GeOp, args);
case BinaryOperator.Opcode.Gt:
return Gen.Function(VCExpressionGenerator.GtOp, args);
case BinaryOperator.Opcode.Imp:
return Gen.Function(VCExpressionGenerator.ImpliesOp, args);
case BinaryOperator.Opcode.And:
return Gen.Function(VCExpressionGenerator.AndOp, args);
case BinaryOperator.Opcode.Or:
return Gen.Function(VCExpressionGenerator.OrOp, args);
case BinaryOperator.Opcode.Subtype:
return Gen.Function(VCExpressionGenerator.SubtypeOp, args);
default:
assert false; // unexpected binary operator
}
}
///////////////////////////////////////////////////////////////////////////////
private VCExpr! TranslateFunctionCall(FunctionCall! app,
List<VCExpr!>! args, List<Type!>! typeArgs) {
assert app.Func != null; // resolution must have happened
VCExpr res = ApplyExpansion(app, args, typeArgs);
if (res != null)
return res;
VCExprOp! functionOp = Gen.BoogieFunctionOp(app.Func);
return Gen.Function(functionOp, args, typeArgs);
}
private VCExpr ApplyExpansion(FunctionCall! app,
List<VCExpr!>! args, List<Type!>! typeArgs) {
assert app.Func != null; // resolution must have happened
if (app.Func.doingExpansion) {
System.Console.WriteLine("*** detected expansion loop on {0}", app.Func);
return null;
}
Expansion exp = FindExpansion(app.Func);
if (exp == null)
return null;
VCExpr! translatedBody;
VCExprSubstitution! subst = new VCExprSubstitution();
try {
BaseTranslator.PushFormalsScope();
BaseTranslator.PushBoundVariableScope();
app.Func.doingExpansion = true;
// first bind the formals to VCExpr variables, which are later
// substituted with the actual parameters
for (int i = 0; i < exp.formals.Length; ++i)
subst[BaseTranslator.BindVariable((!)exp.formals[i])] = args[i];
// recursively translate the body of the expansion
translatedBody = BaseTranslator.Translate(exp.body);
} finally {
BaseTranslator.PopFormalsScope();
BaseTranslator.PopBoundVariableScope();
app.Func.doingExpansion = false;
}
// substitute the formals with the actual parameters in the body
assert typeArgs.Count == exp.TypeParameters.Length;
for (int i = 0; i < typeArgs.Count; ++i)
subst[exp.TypeParameters[i]] = typeArgs[i];
SubstitutingVCExprVisitor! substituter = new SubstitutingVCExprVisitor (Gen);
return substituter.Mutate(translatedBody, subst);
}
private Expansion? FindExpansion(Function! func)
{
if (func.expansions == null) return null;
Expansion? exp = null;
foreach (Expansion! e in func.expansions) {
if (e.ignore == null || !GenerationOptions.IsAnyProverCommandSupported(e.ignore)) {
if (exp == null) {
exp = e;
} else {
System.Console.WriteLine("*** more than one possible expansion for {0}", func);
return null;
}
}
}
return exp;
}
}
}
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