private void collectBoogieCmds(BoogieCmd cmd, List <BoogieCmd> cmds)
{
if (cmd is BoogieStructuredCmd)
{
if (cmd is BoogieIfCmd)
{
BoogieIfCmd ifCmd = (BoogieIfCmd)cmd;
foreach (var c in ifCmd.ThenBody.BigBlocks[0].SimpleCmds)
{
collectBoogieCmds(c, cmds);
}
if (ifCmd.ElseBody != null)
{
foreach (var c in ifCmd.ElseBody.BigBlocks[0].SimpleCmds)
{
collectBoogieCmds(c, cmds);
}
}
}
else if (cmd is BoogieWhileCmd)
{
BoogieWhileCmd whileCmd = (BoogieWhileCmd)cmd;
foreach (var c in whileCmd.Body.BigBlocks[0].SimpleCmds)
{
collectBoogieCmds(c, cmds);
}
}
else
{
cmds.Add(cmd);
}
}
else
{
cmds.Add(cmd);
}
}
// generate a non-deterministic choice block to call every public visible functions except constructors
private BoogieIfCmd GenerateChoiceBlock(ContractDefinition contract)
{
HashSet <FunctionDefinition> funcDefs = context.GetVisibleFunctionsByContract(contract);
List <FunctionDefinition> publicFuncDefs = new List <FunctionDefinition>();
foreach (FunctionDefinition funcDef in funcDefs)
{
if (funcDef.IsConstructorForContract(contract.Name))
{
continue;
}
if (funcDef.Visibility == EnumVisibility.PUBLIC || funcDef.Visibility == EnumVisibility.EXTERNAL)
{
publicFuncDefs.Add(funcDef);
}
}
BoogieIfCmd ifCmd = null;
for (int i = publicFuncDefs.Count - 1; i >= 0; --i)
{
BoogieExpr guard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ,
new BoogieIdentifierExpr("choice"),
new BoogieLiteralExpr(i + 1));
BoogieStmtList thenBody = new BoogieStmtList();
FunctionDefinition funcDef = publicFuncDefs[i];
string callee = TransUtils.GetCanonicalFunctionName(funcDef, context);
List <BoogieExpr> inputs = new List <BoogieExpr>()
{
new BoogieIdentifierExpr("this"),
new BoogieIdentifierExpr("msgsender_MSG"),
new BoogieIdentifierExpr("msgvalue_MSG"),
};
foreach (VariableDeclaration param in funcDef.Parameters.Parameters)
{
string name = TransUtils.GetCanonicalLocalVariableName(param);
inputs.Add(new BoogieIdentifierExpr(name));
if (param.TypeName is ArrayTypeName array)
{
thenBody.AddStatement(new BoogieCallCmd(
"FreshRefGenerator",
new List <BoogieExpr>(), new List <BoogieIdentifierExpr>()
{
new BoogieIdentifierExpr(name)
}));
}
}
List <BoogieIdentifierExpr> outputs = new List <BoogieIdentifierExpr>();
var retParamCount = 0;
foreach (VariableDeclaration param in funcDef.ReturnParameters.Parameters)
{
//string name = "__ret" + funcDef.Name;
string name = $"__ret_{retParamCount++}_" + funcDef.Name;
if (!string.IsNullOrEmpty(param.Name))
{
name = TransUtils.GetCanonicalLocalVariableName(param);
}
outputs.Add(new BoogieIdentifierExpr(name));
}
BoogieCallCmd callCmd = new BoogieCallCmd(callee, inputs, outputs);
thenBody.AddStatement(callCmd);
BoogieStmtList elseBody = ifCmd == null ? null : BoogieStmtList.MakeSingletonStmtList(ifCmd);
ifCmd = new BoogieIfCmd(guard, thenBody, elseBody);
}
return(ifCmd);
}
private BoogieStmtList GenerateBodyOfFallbackDispatch(List <BoogieVariable> inParams, string fbUnknownProcName)
{
// Perform the payable logic to transfer balance
//
// Fallback(from, to, amount)
//
// foreach contract C that is not Lib/VeriSol
// if (DT[this] == C)
// if C has a fallback f
// call ret := fallBack_C(this=to, sender=from, msg.value)
// else
// assume msg.value == 0;
// else
// if stubModel == callback
// call fallBack_unknownType(from, to, amout) //we switch the order of first two parameters to ease callbacks
// else if stubmodel == havoc
// havoc all global state, except local state of this contract
// else
// skip //default
BoogieIfCmd ifCmd = null;
Debug.Assert(context.ContractDefinitions.Count >= 1, "There should be at least one contract");
List <BoogieIdentifierExpr> outParams = new List <BoogieIdentifierExpr>();
List <BoogieExpr> unkwnFnArgs = new List <BoogieExpr>()
{
new BoogieIdentifierExpr(inParams[0].Name),
new BoogieIdentifierExpr(inParams[1].Name),
new BoogieIdentifierExpr(inParams[2].Name)
};
// fbUnknown(from, to, amount)
BoogieStmtList noMatchCase = BoogieStmtList.MakeSingletonStmtList(
new BoogieCallCmd(fbUnknownProcName, unkwnFnArgs, outParams));
foreach (var contract in context.ContractDefinitions)
{
if (contract.ContractKind == EnumContractKind.LIBRARY)
{
continue;
}
FunctionDefinition function = context.ContractToFallbackMap.ContainsKey(contract) ?
context.ContractToFallbackMap[contract] : null;
BoogieExpr lhs = new BoogieMapSelect(new BoogieIdentifierExpr("DType"), new BoogieIdentifierExpr(inParams[1].Name));
BoogieExpr rhs = new BoogieIdentifierExpr(contract.Name);
BoogieExpr guard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ, lhs, rhs);
BoogieStmtList thenBody = null;
if (function != null)
{
List <BoogieExpr> arguments = new List <BoogieExpr>()
{
new BoogieIdentifierExpr(inParams[1].Name),
new BoogieIdentifierExpr(inParams[0].Name),
new BoogieIdentifierExpr(inParams[2].Name)
};
string callee = TransUtils.GetCanonicalFunctionName(function, context);
// to.fallback(from, amount), thus need to switch param0 and param1
thenBody = BoogieStmtList.MakeSingletonStmtList(new BoogieCallCmd(callee, arguments, outParams));
}
else
{
// No fallback means not payable (amount == 0)
thenBody = BoogieStmtList.MakeSingletonStmtList(
new BoogieAssumeCmd(
new BoogieBinaryOperation(
BoogieBinaryOperation.Opcode.EQ,
new BoogieIdentifierExpr(inParams[2].Name),
new BoogieLiteralExpr(BigInteger.Zero)))
);
}
BoogieStmtList elseBody = ifCmd == null ? noMatchCase : BoogieStmtList.MakeSingletonStmtList(ifCmd);
ifCmd = new BoogieIfCmd(guard, thenBody, elseBody);
}
return(BoogieStmtList.MakeSingletonStmtList(ifCmd));
}
private BoogieStmtList CreateBodyOfUnknownFallback(List <BoogieVariable> fbLocalVars, List <BoogieVariable> inParams)
{
Debug.Assert(context.TranslateFlags.ModelStubsAsSkips() || context.TranslateFlags.ModelStubsAsCallbacks() || context.TranslateFlags.ModelStubsAsMultipleCallbacks(),
"CreateBodyOfUnknownFallback called in unexpected context");
var procBody = new BoogieStmtList();
/*procBody.AddStatement(new BoogieCommentCmd("---- Logic for payable function START "));
* var balnSender = new BoogieMapSelect(new BoogieIdentifierExpr("Balance"), new BoogieIdentifierExpr(inParams[0].Name));
* var balnThis = new BoogieMapSelect(new BoogieIdentifierExpr("Balance"), new BoogieIdentifierExpr(inParams[1].Name));
* var msgVal = new BoogieIdentifierExpr("amount");
* //assume Balance[msg.sender] >= msg.value
* procBody.AddStatement(new BoogieAssumeCmd(new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.GE, balnSender, msgVal)));
* //balance[from] = balance[from] - msg.value
* procBody.AddStatement(new BoogieAssignCmd(balnSender, new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.SUB, balnSender, msgVal)));
* //balance[to] = balance[to] + msg.value
* procBody.AddStatement(new BoogieAssignCmd(balnThis, new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.ADD, balnThis, msgVal)));
* procBody.AddStatement(new BoogieCommentCmd("---- Logic for payable function END "));*/
BoogieStmtList body = procBody;
if (context.TranslateFlags.ModelStubsAsCallbacks() ||
context.TranslateFlags.ModelStubsAsMultipleCallbacks())
{
if (context.TranslateFlags.ModelReverts)
{
BoogieBinaryOperation revertGuard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ, new BoogieIdentifierExpr("choice"), new BoogieLiteralExpr(BigInteger.Zero));
BoogieStmtList thenBody = new BoogieStmtList();
thenBody.AddStatement(new BoogieAssignCmd(new BoogieIdentifierExpr("revert"), new BoogieLiteralExpr(true)));
thenBody.AddStatement(new BoogieReturnCmd());
BoogieIfCmd earlyExitCmd = new BoogieIfCmd(revertGuard, thenBody, null);
body.AddStatement(earlyExitCmd);
}
if (context.TranslateFlags.InstrumentGas)
{
BoogieBinaryOperation gasGuard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.LT, new BoogieIdentifierExpr("gas"), new BoogieLiteralExpr(TranslatorContext.TX_GAS_COST));
BoogieIfCmd earlyExitCmd = new BoogieIfCmd(gasGuard, BoogieStmtList.MakeSingletonStmtList(new BoogieReturnCmd()), null);
body.AddStatement(earlyExitCmd);
}
}
if (context.TranslateFlags.ModelStubsAsMultipleCallbacks())
{
fbLocalVars.Add(new BoogieLocalVariable(new BoogieTypedIdent("iterate", BoogieType.Bool)));
BoogieBinaryOperation gasGuard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.GE, new BoogieIdentifierExpr("gas"), new BoogieLiteralExpr(TranslatorContext.TX_GAS_COST));
BoogieBinaryOperation guard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.AND, new BoogieIdentifierExpr("iterate"), gasGuard);
BoogieStmtList loopBody = new BoogieStmtList();
procBody.AddStatement(new BoogieWhileCmd(guard, loopBody, new List <BoogieExpr>()));
body = loopBody;
}
if (context.TranslateFlags.ModelStubsAsCallbacks() || context.TranslateFlags.ModelStubsAsMultipleCallbacks())
{
List <BoogieVariable> localVars = TransUtils.CollectLocalVars(context.ContractDefinitions.ToList(), context);
fbLocalVars.AddRange(localVars);
// if (*) fn1(from, *, ...)
// we only redirect the calling contract, but the msg.sender need not be to, as it can call into anohter contract that calls
// into from
if (context.TranslateFlags.ModelStubsAsMultipleCallbacks())
{
body.AppendStmtList(HavocLocals(localVars));
body.AddStatement(new BoogieHavocCmd(new BoogieIdentifierExpr("iterate")));
}
BoogieIfCmd typeIf = null;
foreach (ContractDefinition curDef in context.ContractDefinitions.ToList())
{
BoogieIfCmd reentrantCalls = TransUtils.GenerateChoiceBlock(new List <ContractDefinition>()
{
curDef
},
context, false, Tuple.Create(inParams[0].Name, inParams[1].Name));
if (reentrantCalls == null)
{
continue;
}
BoogieExpr dtype = new BoogieMapSelect(new BoogieIdentifierExpr("DType"), new BoogieIdentifierExpr(inParams[0].Name));
BoogieBinaryOperation guard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ, dtype, new BoogieIdentifierExpr(curDef.Name));
typeIf = new BoogieIfCmd(guard, BoogieStmtList.MakeSingletonStmtList(reentrantCalls), typeIf == null ? null : BoogieStmtList.MakeSingletonStmtList(typeIf));
}
/*BoogieIfCmd ifCmd = null;
*
* if (context.TranslateFlags.ModelReverts)
* {
* BoogieExpr guard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ,
* new BoogieIdentifierExpr("choice"),
* new BoogieLiteralExpr(choices.Item2 + 1));
*
* BoogieAssignCmd assign = new BoogieAssignCmd(new BoogieIdentifierExpr("revert"), new BoogieLiteralExpr(true));
* ifCmd = new BoogieIfCmd(guard, BoogieStmtList.MakeSingletonStmtList(assign), BoogieStmtList.MakeSingletonStmtList(choices.Item1));
* }
* else
* {
* ifCmd = choices.Item1;
* }*/
body.AddStatement(typeIf);
}
return(procBody);
}
/// <summary>
/// generate a non-deterministic choice block to call every public visible functions except constructors
///
/// </summary>
/// <param name="contracts"></param>
/// <param name="context"></param>
/// <param name="callBackTarget">If non-null, this will be the msg.sender for calling back into the contracts</param>
/// <returns></returns>
public static BoogieIfCmd GenerateChoiceBlock(List <ContractDefinition> contracts, TranslatorContext context, Tuple <string, string> callBackTarget = null)
{
BoogieIfCmd ifCmd = null;
int j = 0;
foreach (var contract in contracts)
{
if (contract.ContractKind != EnumContractKind.CONTRACT)
{
continue;
}
HashSet <FunctionDefinition> funcDefs = context.GetVisibleFunctionsByContract(contract);
List <FunctionDefinition> publicFuncDefs = new List <FunctionDefinition>();
foreach (FunctionDefinition funcDef in funcDefs)
{
if (funcDef.IsConstructor)
{
continue;
}
if (funcDef.IsFallback)
{
continue; //let us not call fallback directly in harness
}
if (funcDef.Visibility == EnumVisibility.PUBLIC || funcDef.Visibility == EnumVisibility.EXTERNAL)
{
publicFuncDefs.Add(funcDef);
}
}
for (int i = publicFuncDefs.Count - 1; i >= 0; --i)
{
j++;
BoogieExpr guard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ,
new BoogieIdentifierExpr("choice"),
new BoogieLiteralExpr(j));
BoogieStmtList thenBody = new BoogieStmtList();
FunctionDefinition funcDef = publicFuncDefs[i];
string callee = TransUtils.GetCanonicalFunctionName(funcDef, context);
List <BoogieExpr> inputs = new List <BoogieExpr>()
{
// let us just call back into the calling contract
callBackTarget != null ? new BoogieIdentifierExpr(callBackTarget.Item1) : new BoogieIdentifierExpr("this"),
callBackTarget != null ? new BoogieIdentifierExpr(callBackTarget.Item2) : new BoogieIdentifierExpr("msgsender_MSG"),
new BoogieIdentifierExpr("msgvalue_MSG"),
};
foreach (VariableDeclaration param in funcDef.Parameters.Parameters)
{
string name = TransUtils.GetCanonicalLocalVariableName(param);
inputs.Add(new BoogieIdentifierExpr(name));
if (param.TypeName is ArrayTypeName array)
{
thenBody.AddStatement(new BoogieCallCmd(
"FreshRefGenerator",
new List <BoogieExpr>(), new List <BoogieIdentifierExpr>()
{
new BoogieIdentifierExpr(name)
}));
}
}
List <BoogieIdentifierExpr> outputs = new List <BoogieIdentifierExpr>();
var retParamCount = 0;
foreach (VariableDeclaration param in funcDef.ReturnParameters.Parameters)
{
string name = $"__ret_{retParamCount++}_" + funcDef.Name;
if (!string.IsNullOrEmpty(param.Name))
{
name = TransUtils.GetCanonicalLocalVariableName(param);
}
outputs.Add(new BoogieIdentifierExpr(name));
}
if (context.TranslateFlags.InstrumentGas)
{
havocGas(thenBody);
}
BoogieCallCmd callCmd = new BoogieCallCmd(callee, inputs, outputs);
thenBody.AddStatement(callCmd);
BoogieStmtList elseBody = ifCmd == null ? null : BoogieStmtList.MakeSingletonStmtList(ifCmd);
ifCmd = new BoogieIfCmd(guard, thenBody, elseBody);
}
}
return(ifCmd);
}
private BoogieStmtList GenerateBody(List <BoogieVariable> inParams)
{
//
// foreach contract C that is not Lib/VeriSol
// if (DT[this] == C)
// if C has a fallback f
// call ret := fallBack_C(this=to, sender=from, msg.value)
// else
// assume msg.value == 0;
// else
// call fallBack_unknownType(from, to, msg.value)
BoogieIfCmd ifCmd = null;
Debug.Assert(context.ContractDefinitions.Count >= 1, "There should be at least one contract");
List <BoogieExpr> arguments = new List <BoogieExpr>()
{
new BoogieIdentifierExpr(inParams[1].Name),
new BoogieIdentifierExpr(inParams[0].Name),
new BoogieIdentifierExpr(inParams[2].Name)
};
List <BoogieIdentifierExpr> outParams = new List <BoogieIdentifierExpr>();
BoogieStmtList noMatchCase = BoogieStmtList.MakeSingletonStmtList(
new BoogieCallCmd("Fallback_UnknownType", arguments, outParams));
foreach (var contract in context.ContractDefinitions)
{
if (contract.ContractKind == EnumContractKind.LIBRARY)
{
continue;
}
FunctionDefinition function = context.ContractToFallbackMap.ContainsKey(contract) ?
context.ContractToFallbackMap[contract] : null;
BoogieExpr lhs = new BoogieMapSelect(new BoogieIdentifierExpr("DType"), new BoogieIdentifierExpr(inParams[1].Name));
BoogieExpr rhs = new BoogieIdentifierExpr(contract.Name);
BoogieExpr guard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ, lhs, rhs);
BoogieStmtList thenBody = null;
if (function != null)
{
string callee = TransUtils.GetCanonicalFunctionName(function, context);
thenBody = BoogieStmtList.MakeSingletonStmtList(new BoogieCallCmd(callee, arguments, outParams));
}
else
{
// No fallback means not payable (amount == 0)
thenBody = BoogieStmtList.MakeSingletonStmtList(
new BoogieAssumeCmd(
new BoogieBinaryOperation(
BoogieBinaryOperation.Opcode.EQ,
new BoogieIdentifierExpr(inParams[2].Name),
new BoogieLiteralExpr(BigInteger.Zero)))
);
}
BoogieStmtList elseBody = ifCmd == null ? noMatchCase : BoogieStmtList.MakeSingletonStmtList(ifCmd);
ifCmd = new BoogieIfCmd(guard, thenBody, elseBody);
}
return(BoogieStmtList.MakeSingletonStmtList(ifCmd));
}
public static Tuple <BoogieIfCmd, int> GeneratePartialChoiceBlock(List <ContractDefinition> contracts, TranslatorContext context, BoogieExpr thisExpr, int startingPoint, bool canRevert, BoogieIfCmd alternatives = null, Tuple <string, string> callBackTarget = null)
{
BoogieIfCmd ifCmd = alternatives;
int j = startingPoint;
foreach (var contract in contracts)
{
if (contract.ContractKind != EnumContractKind.CONTRACT)
{
continue;
}
HashSet <FunctionDefinition> funcDefs = context.GetVisibleFunctionsByContract(contract);
List <FunctionDefinition> publicFuncDefs = new List <FunctionDefinition>();
foreach (FunctionDefinition funcDef in funcDefs)
{
if (funcDef.IsConstructor)
{
continue;
}
if (funcDef.IsFallback)
{
continue; //let us not call fallback directly in harness
}
if (context.TranslateFlags.PerformFunctionSlice &&
!context.TranslateFlags.SliceFunctions.Contains(funcDef))
{
continue;
}
if (funcDef.Visibility == EnumVisibility.PUBLIC || funcDef.Visibility == EnumVisibility.EXTERNAL)
{
publicFuncDefs.Add(funcDef);
}
}
for (int i = publicFuncDefs.Count - 1; i >= 0; --i)
{
j++;
BoogieExpr guard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ,
new BoogieIdentifierExpr("choice"),
new BoogieLiteralExpr(j));
BoogieStmtList thenBody = new BoogieStmtList();
FunctionDefinition funcDef = publicFuncDefs[i];
string callee = TransUtils.GetCanonicalFunctionName(funcDef, context);
List <BoogieExpr> inputs = new List <BoogieExpr>()
{
// let us just call back into the calling contract
callBackTarget != null ? new BoogieIdentifierExpr(callBackTarget.Item1) : thisExpr,
callBackTarget != null ? new BoogieIdentifierExpr(callBackTarget.Item2) : new BoogieIdentifierExpr("msgsender_MSG"),
new BoogieIdentifierExpr("msgvalue_MSG"),
};
var inpParamCount = 0;
foreach (VariableDeclaration param in funcDef.Parameters.Parameters)
{
string name = $"__arg_{inpParamCount++}_" + funcDef.Name;
if (!string.IsNullOrEmpty(param.Name))
{
name = TransUtils.GetCanonicalLocalVariableName(param, context);
}
BoogieIdentifierExpr boogieVar = new BoogieIdentifierExpr(name);
inputs.Add(boogieVar);
if (param.TypeName is ArrayTypeName array)
{
thenBody.AddStatement(new BoogieCallCmd(
"FreshRefGenerator",
new List <BoogieExpr>(), new List <BoogieIdentifierExpr>()
{
new BoogieIdentifierExpr(name)
}));
}
thenBody.AppendStmtList(constrainVarValues(context, param, boogieVar));
}
List <BoogieIdentifierExpr> outputs = new List <BoogieIdentifierExpr>();
var retParamCount = 0;
foreach (VariableDeclaration param in funcDef.ReturnParameters.Parameters)
{
string name = $"__ret_{retParamCount++}_" + funcDef.Name;
if (!string.IsNullOrEmpty(param.Name))
{
name = TransUtils.GetCanonicalLocalVariableName(param, context);
}
outputs.Add(new BoogieIdentifierExpr(name));
}
if (funcDef.StateMutability.Equals(EnumStateMutability.PAYABLE))
{
BoogieExpr assumeExpr = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.GE,
new BoogieIdentifierExpr("msgvalue_MSG"), new BoogieLiteralExpr(BigInteger.Zero));
thenBody.AddStatement(new BoogieAssumeCmd(assumeExpr));
if (!canRevert)
{
thenBody.AddStatement(new BoogieCommentCmd("---- Logic for payable function START "));
var balnSender = new BoogieMapSelect(new BoogieIdentifierExpr("Balance"), new BoogieIdentifierExpr("msgsender_MSG"));
var balnThis = new BoogieMapSelect(new BoogieIdentifierExpr("Balance"), new BoogieIdentifierExpr("this"));
var msgVal = new BoogieIdentifierExpr("msgvalue_MSG");
//assume Balance[msg.sender] >= msg.value
thenBody.AddStatement(new BoogieAssumeCmd(new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.GE, balnSender, msgVal)));
//balance[msg.sender] = balance[msg.sender] - msg.value
thenBody.AddStatement(new BoogieAssignCmd(balnSender, new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.SUB, balnSender, msgVal)));
//balance[this] = balance[this] + msg.value
thenBody.AddStatement(new BoogieAssignCmd(balnThis, new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.ADD, balnThis, msgVal)));
thenBody.AddStatement(new BoogieCommentCmd("---- Logic for payable function END "));
}
}
else
{
BoogieExpr assumeExpr = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ,
new BoogieIdentifierExpr("msgvalue_MSG"), new BoogieLiteralExpr(BigInteger.Zero));
thenBody.AddStatement(new BoogieAssumeCmd(assumeExpr));
}
BoogieCallCmd callCmd = new BoogieCallCmd(callee, inputs, outputs);
thenBody.AddStatement(callCmd);
if (context.TranslateFlags.InstrumentGas)
{
var gasVar = new BoogieIdentifierExpr("gas");
BoogieBinaryOperation gasGuard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.GE, gasVar, new BoogieLiteralExpr(BigInteger.Zero));
BoogieIfCmd ifExpr = new BoogieIfCmd(gasGuard, thenBody, null);
thenBody = new BoogieStmtList();
//thenBody.AddStatement(new BoogieAssumeCmd(new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.GE, gasVar, new BoogieLiteralExpr(TranslatorContext.TX_GAS_COST))));
thenBody.AddStatement(new BoogieAssignCmd(gasVar, new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.SUB, gasVar, new BoogieLiteralExpr(TranslatorContext.TX_GAS_COST))));
thenBody.AddStatement(ifExpr);
}
BoogieStmtList elseBody = ifCmd == null ? null : BoogieStmtList.MakeSingletonStmtList(ifCmd);
ifCmd = new BoogieIfCmd(guard, thenBody, elseBody);
}
}
return(new Tuple <BoogieIfCmd, int>(ifCmd, j));
}