Keep original slithIR and generate the SSA version as a second list of IR (WIP)

slither/__main__.py

@@ -157,6 +157,7 @@ def get_detectors_and_printers():
     from slither.printers.call.call_graph import PrinterCallGraph
     from slither.printers.functions.authorization import PrinterWrittenVariablesAndAuthorization
     from slither.printers.summary.slithir import PrinterSlithIR
+    from slither.printers.summary.slithir_ssa import PrinterSlithIRSSA
     from slither.printers.summary.human_summary import PrinterHumanSummary
 
     printers = [FunctionSummary,
@@ -166,6 +167,7 @@ def get_detectors_and_printers():
                 PrinterCallGraph,
                 PrinterWrittenVariablesAndAuthorization,
                 PrinterSlithIR,
+                PrinterSlithIRSSA,
                 PrinterHumanSummary]
 
     # Handle plugins!
@@ -213,6 +215,7 @@ def main_impl(all_detector_classes, all_printer_classes):
                               ('FunctionSolc', default_log),
                               ('ExpressionParsing', default_log),
                               ('TypeParsing', default_log),
+                              ('SSA_Conversion', default_log),
                               ('Printers', default_log)]:
         l = logging.getLogger(l_name)
         l.setLevel(l_level)

slither/core/cfg/node.py

@@ -131,6 +131,7 @@ class Node(SourceMapping, ChildFunction):
         self._low_level_calls = []
         self._external_calls_as_expressions = []
         self._irs = []
+        self._irs_ssa = []
 
         self._state_vars_written = []
         self._state_vars_read = []
@@ -424,8 +425,24 @@ class Node(SourceMapping, ChildFunction):
         """
         return self._irs
 
-    def add_pre_ir(self, ir):
-        self._irs.insert(0, ir)
+    @property
+    def irs_ssa(self):
+        """ Returns the slithIR representation with SSA
+
+        return
+            list(slithIR.Operation)
+        """
+        return self._irs_ssa
+
+    @irs_ssa.setter
+    def irs_ssa(self, irs):
+       self._irs_ssa = irs
+
+    def add_ssa_ir(self, ir):
+        '''
+            Use to place phi operation
+        '''
+        self._irs_ssa.append(ir)
 
     def slithir_generation(self):
         if self.expression:

slither/slithir/operations/high_level_call.py

@@ -13,7 +13,7 @@ class HighLevelCall(Call, OperationWithLValue):
 
     def __init__(self, destination, function_name, nbr_arguments, result, type_call):
         assert isinstance(function_name, Constant)
-        assert is_valid_lvalue(result)
+        assert is_valid_lvalue(result) or result is None
         self._check_destination(destination)
         super(HighLevelCall, self).__init__()
         self._destination = destination

slither/slithir/operations/index.py

@@ -33,5 +33,9 @@ class Index(OperationWithLValue):
     def variable_right(self):
         return self._variables[1]
 
+    @property
+    def index_type(self):
+        return self._type
+
     def __str__(self):
         return "{}({}) -> {}[{}]".format(self.lvalue, self.lvalue.type, self.variable_left, self.variable_right)

slither/slithir/operations/unary.py

@@ -48,6 +48,10 @@ class Unary(OperationWithLValue):
     def rvalue(self):
         return self._variable
 
+    @property
+    def type(self):
+        return self._type
+
     @property
     def type_str(self):
         return UnaryType.str(self._type)

slither/slithir/utils/ssa.py

@@ -1,7 +1,25 @@
-from slither.slithir.variables import (Constant, ReferenceVariable,
-                                       TemporaryVariable, TupleVariable)
-from slither.slithir.operations import OperationWithLValue, Phi
-from slither.slithir.variables import LocalIRVariable
+import logging
+
+from slither.core.cfg.node import NodeType
+from slither.core.variables.local_variable import LocalVariable
+from slither.slithir.operations import (Assignment, Balance, Binary,
+                                        BinaryType, Condition, Delete,
+                                        EventCall, HighLevelCall, Index,
+                                        InitArray, InternalCall,
+                                        InternalDynamicCall, Length,
+                                        LibraryCall, LowLevelCall, Member,
+                                        NewArray, NewContract,
+                                        NewElementaryType, NewStructure,
+                                        OperationWithLValue, Phi, Push, Return,
+                                        Send, SolidityCall, Transfer,
+                                        TypeConversion, Unary, Unpack)
+from slither.slithir.variables import (Constant, LocalIRVariable,
+                                       ReferenceVariable, TemporaryVariable,
+                                       TupleVariable)
+
+logger = logging.getLogger('SSA_Conversion')
+
+
 
 def transform_slithir_vars_to_ssa(function):
     """
@@ -9,7 +27,7 @@ def transform_slithir_vars_to_ssa(function):
     """
     variables = []
     for node in function.nodes:
-        for ir in node.irs:
+        for ir in node.irs_ssa:
             if isinstance(ir, OperationWithLValue) and not ir.lvalue in variables:
                 variables += [ir.lvalue]
 
@@ -23,12 +41,18 @@ def transform_slithir_vars_to_ssa(function):
     for idx in range(len(tuple_variables)):
         tuple_variables[idx].index = idx
 
-def add_phi_operations(function):
+def add_ssa_ir(function):
+    '''
+        Add SSA version of the IR
+    '''
+
+    if not function.is_implemented:
+        return
+
     init_definition = dict()
     for v in function.parameters+function.returns:
         if v.name:
             init_definition[v.name] = function.entry_point
-
     add_phi_origins(function.entry_point, init_definition)
 
     for node in function.nodes:
@@ -39,57 +63,75 @@ def add_phi_operations(function):
             # an instance of the variable
             # by looking at the variables written
             # of any of the nodes
-            n = list(nodes)[0]
+            for n in nodes:
                 variable = next((v for v in n.variables_written if v.name == variable_name), None)
                 if variable is None:
                     variable = n.variable_declaration
-            node.add_pre_ir(Phi(LocalIRVariable(variable), nodes))
+                if variable:
+                    break
+            assert variable
+            node.add_ssa_ir(Phi(LocalIRVariable(variable), nodes))
 
-    init_local_variables_counter = dict()
+    init_local_variables_instances = dict()
     for v in function.parameters+function.returns:
         if v.name:
-            init_local_variables_counter[v.name] = 0
-    init_global_variables_counter = dict(init_local_variables_counter)
-    rename_variables(function.entry_point, init_local_variables_counter, init_global_variables_counter)
+            init_local_variables_instances[v.name] = LocalIRVariable(v)
+    init_global_variables_instances = dict(init_local_variables_instances)
+    generate_ssa_irs(function.entry_point,
+                     dict(init_local_variables_instances),
+                     init_global_variables_instances)
 
-    fix_phi_operations(function.nodes)
+    fix_phi_operations(function.nodes, init_local_variables_instances)
 
-def fix_phi_operations(nodes):
+
+def fix_phi_operations(nodes, init_vars):
     def last_name(n, var):
-        candidates = [v for v in n.variables_written if v.name == var.name]
+        candidates = []
+        # Todo optimize by creating a variables_ssa_written attribute
+        for ir_ssa in n.irs_ssa:
+            if isinstance(ir_ssa, OperationWithLValue):
+                if ir_ssa.lvalue and ir_ssa.lvalue.name == var.name:
+                    candidates.append(ir_ssa.lvalue)
         if n.variable_declaration and n.variable_declaration.name == var.name:
             candidates.append(LocalIRVariable(n.variable_declaration))
+        if n.type == NodeType.ENTRYPOINT:
+            if var.name in init_vars:
+                candidates.append(init_vars[var.name])
         assert candidates
         return max(candidates, key=lambda v: v.index)
 
     for node in nodes:
-        for ir in node.irs:
+        for ir in node.irs_ssa:
             if isinstance(ir, Phi):
                 variables = [last_name(dst, ir.lvalue) for dst in ir.nodes]
                 ir.rvalues = variables
 
-def rename_variables(node, local_variables_counter, global_variables_counter):
+def generate_ssa_irs(node, local_variables_instances, global_variables_instances):
 
     if node.variable_declaration:
-        local_variables_counter[node.variable_declaration.name] = 0
-        global_variables_counter[node.variable_declaration.name] = 0
-
-    for idx in range(len(node.irs)):
-        ir = node.irs[idx]
-        for used in ir.used:
-            if isinstance(used, LocalIRVariable):
-                used.index = local_variables_counter[used.name]
-
-        if isinstance(ir, OperationWithLValue):
-            if isinstance(ir.lvalue, LocalIRVariable):
-                counter = global_variables_counter[ir.lvalue.name]
-                counter = counter + 1
-                global_variables_counter[ir.lvalue.name] = counter
-                local_variables_counter[ir.lvalue.name] = counter
-                ir.lvalue.index = counter
+        new_var = LocalIRVariable(node.variable_declaration)
+        local_variables_instances[node.variable_declaration.name] = new_var
+        global_variables_instances[node.variable_declaration.name] = new_var
+
+    for ir in node.irs:
+#        ir = node.irs[idx]
+#        for used in ir.used:
+#            if isinstance(used, LocalIRVariable):
+#                used.index = local_variables_instances[used.name]
+        new_ir = copy_ir(ir, local_variables_instances)
+        if new_ir:
+            node.add_ssa_ir(new_ir)
+
+        if isinstance(new_ir, OperationWithLValue):
+            if isinstance(new_ir.lvalue, LocalIRVariable):
+                new_var = LocalIRVariable(new_ir.lvalue)
+                new_var.index = global_variables_instances[new_ir.lvalue.name].index + 1
+                global_variables_instances[new_ir.lvalue.name] = new_var
+                local_variables_instances[new_ir.lvalue.name] = new_var
+                new_ir.lvalue = new_var
 
     for succ in node.dominator_successors:
-        rename_variables(succ, dict(local_variables_counter), global_variables_counter)
+        generate_ssa_irs(succ, dict(local_variables_instances), global_variables_instances)
 
 def add_phi_origins(node, variables_definition):
 
@@ -112,14 +154,208 @@ def add_phi_origins(node, variables_definition):
 
     if not node.dominator_successors:
         return
-
     for succ in node.dominator_successors:
         add_phi_origins(succ, variables_definition)
 
+def copy_ir(ir, variables_instances):
+    '''
+    Args:
+        ir (Operation)
+        variables_instances(dict(str -> Variable))
+    '''
+
+    def get_variable(ir, f):
+        variable = f(ir)
+        if isinstance(variable, LocalVariable) and variable.name in variables_instances:
+            variable = variables_instances[variable.name]
+        return variable
+
+    def get_arguments(ir):
+        arguments = []
+        for arg in ir.arguments:
+            if isinstance(arg, LocalVariable) and arg.name in variables_instances:
+                arg = variables_instances[arg.name]
+            arguments.append(arg)
+        return arguments
+
+    def get_rec_values(ir, f):
+        # Use by InitArray and NewArray
+        # Potential recursive array(s)
+        ori_init_values = f(ir)
 
+        def traversal(values):
+            ret = []
+            for v in values:
+                if isinstance(v, list):
+                    v = traversal(v)
+                else:
+                    if isinstance(v, LocalVariable) and v.name in variables_instances:
+                        v = variables_instances[v.name]
+                ret.append(v)
+            return ret
+
+        return traversal(ori_init_values)
+
+
+    if isinstance(ir, Assignment):
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        rvalue = get_variable(ir, lambda x: ir.rvalue)
+        variable_return_type = ir.variable_return_type
+        return Assignment(lvalue, rvalue, variable_return_type)
+    elif isinstance(ir, Balance):
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        value = get_variable(ir, lambda x: ir.value)
+        return Balance(value, lvalue)
+    elif isinstance(ir, Binary):
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        variable_left = get_variable(ir, lambda x: ir.variable_left)
+        variable_right = get_variable(ir, lambda x: ir.variable_right)
+        operation_type = ir.type
+        return Binary(lvalue, variable_left, variable_right, operation_type)
+    elif isinstance(ir, Condition):
+        val = get_variable(ir, lambda x: ir.value)
+        return Condition(val)
+    elif isinstance(ir, Delete):
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        variable = get_variable(ir, lambda x: ir.variable)
+        return Delete(lvalue, variable)
+    elif isinstance(ir, EventCall):
+        name = ir.name
+        return EventCall(name)
+    elif isinstance(ir, HighLevelCall): # include LibraryCall
+        destination = get_variable(ir, lambda x: ir.destination)
+        function_name = ir.function_name
+        nbr_arguments = ir.nbr_arguments
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        type_call = ir.type_call
+        if isinstance(ir, LibraryCall):
+            new_ir = LibraryCall(destination, function_name, nbr_arguments, lvalue, type_call)
+        else:
+            new_ir = HighLevelCall(destination, function_name, nbr_arguments, lvalue, type_call)
+        new_ir.call_id = ir.call_id
+        new_ir.call_value = get_variable(ir, lambda x: ir.call_value)
+        new_ir.call_gas = get_variable(ir, lambda x: ir.call_gas)
+        new_ir.arguments = get_arguments(ir)
+        new_ir.function_instance = ir.function
+        return new_ir
+    elif isinstance(ir, Index):
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        variable_left = get_variable(ir, lambda x: ir.variable_left)
+        variable_right = get_variable(ir, lambda x: ir.variable_right)
+        index_type = ir.index_type
+        return Index(lvalue, variable_left, variable_right, index_type)
+    elif isinstance(ir, InitArray):
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        init_values = get_rec_values(ir, lambda x: ir.init_values)
+        return InitArray(init_values, lvalue)
+    elif isinstance(ir, InternalCall):
+        function = ir.function
+        nbr_arguments = ir.nbr_arguments
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        type_call = ir.type_call
+        new_ir = InternalCall(function, nbr_arguments, lvalue, type_call)
+        new_ir.arguments = get_arguments(ir)
+        return new_ir
+    elif isinstance(ir, InternalDynamicCall):
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        function = ir.function
+        function_type = ir.function_type
+        new_ir = InternalDynamicCall(lvalue, function, function_type)
+        new_ir.arguments = get_arguments(ir)
+        return new_ir
+    elif isinstance(ir, LowLevelCall):
+        destination = get_variable(ir, lambda x: x.destination)
+        function_name = ir.function_name
+        nbr_arguments = ir.nbr_arguments
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        type_call = ir.type_call
+        new_ir = LowLevelCall(destination, function_name, nbr_arguments, lvalue, type_call)
+        new_ir.call_id = ir.call_id
+        new_ir.call_value = get_variable(ir, lambda x: ir.call_value)
+        new_ir.call_gas = get_variable(ir, lambda x: ir.call_gas)
+        new_ir.arguments = get_arguments(ir)
+        return new_ir
+    elif isinstance(ir, Member):
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        variable_left = get_variable(ir, lambda x: ir.variable_left)
+        variable_right = get_variable(ir, lambda x: ir.variable_right)
+        return Member(variable_left, variable_right, lvalue)
+    elif isinstance(ir, NewArray):
+        depth = ir.depth
+        array_type = ir.array_type
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        new_ir = NewArray(depth, array_type, lvalue)
+        new_ir.arguments = get_rec_values(ir, lambda x: ir.arguments)
+        return new_ir
+    elif isinstance(ir, NewElementaryType):
+        new_type = ir.type
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        new_ir = NewElementaryType(new_type, lvalue)
+        new_ir.arguments = get_arguments(ir)
+        return new_ir
+    elif isinstance(ir, NewContract):
+        contract_name = ir.contract_name
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        new_ir = NewContract(contract_name, lvalue)
+        new_ir.arguments = get_arguments(ir)
+        return new_ir
+    elif isinstance(ir, NewStructure):
+        structure = ir.structure
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        new_ir = NewStructure(structure, lvalue)
+        new_ir.arguments = get_arguments(ir)
+        return new_ir
+    elif isinstance(ir, Push):
+        array = get_variable(ir, lambda x: ir.array)
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        return Push(array, lvalue)
+    elif isinstance(ir, Return):
+        value = get_variable(ir, lambda x: ir.value)
+        return Return(value)
+    elif isinstance(ir, Send):
+        destination = get_variable(ir, lambda x: ir.destination)
+        value = get_variable(ir, lambda x: ir.call_value)
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        return Send(destination, value, lvalue)
+    elif isinstance(ir, SolidityCall):
+        function = ir.function
+        nbr_arguments = ir.nbr_arguments
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        type_call = ir.type_call
+        new_ir = SolidityCall(function, nbr_arguments, lvalue, type_call)
+        new_ir.arguments = get_arguments(ir)
+        return new_ir
+    elif isinstance(ir, Transfer):
+        destination = get_variable(ir, lambda x: ir.destination)
+        value = get_variable(ir, lambda x: ir.call_value)
+        return Transfer(destination, value)
+    elif isinstance(ir, TypeConversion):
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        variable = get_variable(ir, lambda x: ir.variable)
+        variable_type = ir.type
+        return TypeConversion(lvalue, variable, variable_type)
+    elif isinstance(ir, Unary):
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        rvalue = get_variable(ir, lambda x: ir.rvalue)
+        operation_type = ir.type
+        return Unary(lvalue, rvalue, operation_type)
+    elif isinstance(ir, Unpack):
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        tuple_var = ir.tuple
+        idx = ir.index
+        return Unpack(lvalue, tuple_var, idx)
+    elif isinstance(ir, Length):
+        lvalue = get_variable(ir, lambda x: ir.lvalue)
+        value = get_variable(ir, lambda x: ir.value)
+        return Length(value, lvalue)
+
+
+    logger.error('Impossible ir copy on {} ({})'.format(ir, type(ir)))
+    exit(-1)
 
 def transform_localir_vars_to_ssa(function):
     """
         Transform slithIR vars to SSA
     """
     pass
+

slither/solc_parsing/declarations/function.py

@@ -20,7 +20,7 @@ from slither.visitors.expression.has_conditional import HasConditional
 
 from slither.utils.expression_manipulations import SplitTernaryExpression
 
-from slither.slithir.utils.ssa import transform_slithir_vars_to_ssa, add_phi_operations
+from slither.slithir.utils.ssa import transform_slithir_vars_to_ssa, add_ssa_ir
 
 from slither.core.dominators.utils import compute_dominators, compute_dominance_frontier
 logger = logging.getLogger("FunctionSolc")
@@ -839,8 +839,8 @@ class FunctionSolc(Function):
         compute_dominance_frontier(self.nodes)
         for node in self.nodes:
             node.slithir_generation()
-        add_phi_operations(self)
         transform_slithir_vars_to_ssa(self)
+        add_ssa_ir(self)
         self._analyze_read_write()
         self._analyze_calls()
  

slither/visitors/slithir/expression_to_slithir.py

@@ -20,8 +20,8 @@ from slither.slithir.variables import (Constant, ReferenceVariable,
 from slither.visitors.expression.expression import ExpressionVisitor
 from slither.core.variables.state_variable import StateVariable
 from slither.core.variables.local_variable import LocalVariable
-from slither.slithir.variables.state_variable import StateIRVariable
-from slither.slithir.variables.local_variable import LocalIRVariable
+#from slither.slithir.variables.state_variable import StateIRVariable
+#from slither.slithir.variables.local_variable import LocalIRVariable
 
 logger = logging.getLogger("VISTIOR:ExpressionToSlithIR")
 
@@ -37,8 +37,9 @@ def set_val(expression, val):
     expression.context[key] = val
 
 def convert_assignment(left, right, t, return_type):
-    if isinstance(left, LocalVariable):
-        left = LocalIRVariable(left)
+#    if isinstance(left, LocalVariable):
+#        left = LocalIRVariable(left)
+#        print(left)
     if t == AssignmentOperationType.ASSIGN:
         return Assignment(left, right, return_type)
     elif t == AssignmentOperationType.ASSIGN_OR:
@@ -108,7 +109,7 @@ class ExpressionToSlithIR(ExpressionVisitor):
                 self._result.append(operation)
                 # Return left to handle
                 # a = b = 1; 
-                set_val(expression, left)
+                set_val(expression, operation.lvalue)
 
     def _post_binary_operation(self, expression):
         left = get(expression.expression_left)
@@ -156,12 +157,12 @@ class ExpressionToSlithIR(ExpressionVisitor):
         set_val(expression, expression.type)
 
     def _post_identifier(self, expression):
-        if isinstance(expression.value, StateVariable):
-            set_val(expression, StateIRVariable(expression.value))
-        elif isinstance(expression.value, LocalVariable):
-            set_val(expression, LocalIRVariable(expression.value))
-        else:
-            assert isinstance(expression.value, (SolidityVariable, SolidityFunction, Function, Contract, Enum, Structure))
+#        if isinstance(expression.value, StateVariable):
+#            set_val(expression, StateIRVariable(expression.value))
+#        elif isinstance(expression.value, LocalVariable):
+#            set_val(expression, LocalIRVariable(expression.value))
+#        else:
+            assert isinstance(expression.value, (SolidityVariable, SolidityFunction, Function, Contract, Enum, Structure, StateVariable, LocalVariable))
             set_val(expression, expression.value)
 
     def _post_index_access(self, expression):
@@ -219,9 +220,9 @@ class ExpressionToSlithIR(ExpressionVisitor):
     def _post_unary_operation(self, expression):
         value = get(expression.expression)
         new_value = value
-        # need new instance for ssa
-        if isinstance(new_value, LocalVariable):
-            new_value = LocalIRVariable(new_value)
+     #   # need new instance for ssa
+     #   if isinstance(new_value, LocalVariable):
+     #       new_value = LocalIRVariable(new_value)
         if expression.type in [UnaryOperationType.BANG, UnaryOperationType.TILD]:
             lvalue = TemporaryVariable(self._node)
             operation = Unary(lvalue, value, expression.type)