Instruction:
Given the following Python 3 function, write the documentation
def normalize(self):

        graph = self.graph

        smallest_nodes = { }  # indexed by end address of the node
        end_addresses_to_nodes = defaultdict(set)

        for n in graph.nodes():
            if n.is_simprocedure:
                continue
            end_addr = n.addr + n.size
            key = (end_addr, n.callstack_key)
            # add the new item
            end_addresses_to_nodes[key].add(n)

        for key in list(end_addresses_to_nodes.keys()):
            if len(end_addresses_to_nodes[key]) == 1:
                smallest_nodes[key] = next(iter(end_addresses_to_nodes[key]))
                del end_addresses_to_nodes[key]

        while end_addresses_to_nodes:
            key_to_find = (None, None)
            for tpl, x in end_addresses_to_nodes.items():
                if len(x) > 1:
                    key_to_find = tpl
                    break

            end_addr, callstack_key = key_to_find
            all_nodes = end_addresses_to_nodes[key_to_find]

            all_nodes = sorted(all_nodes, key=lambda node: node.addr, reverse=True)
            smallest_node = all_nodes[0] # take the one that has the highest address
            other_nodes = all_nodes[1:]

            self._normalize_core(graph, callstack_key, smallest_node, other_nodes, smallest_nodes,
                                 end_addresses_to_nodes
                                 )

            del end_addresses_to_nodes[key_to_find]
            # make sure the smallest node is stored in end_addresses
            smallest_nodes[key_to_find] = smallest_node

            # corner case
            # sometimes two overlapping blocks may not be ending at the instruction. this might happen when one of the
            # blocks (the bigger one) hits the instruction count limit or bytes limit before reaching the end address
            # of the smaller block. in this case we manually pick up those blocks.
            if not end_addresses_to_nodes:
                # find if there are still overlapping blocks
                sorted_smallest_nodes = defaultdict(list)  # callstack_key is the key of this dict
                for k, node in smallest_nodes.items():
                    _, callstack_key = k
                    sorted_smallest_nodes[callstack_key].append(node)
                for k in sorted_smallest_nodes.keys():
                    sorted_smallest_nodes[k] = sorted(sorted_smallest_nodes[k], key=lambda node: node.addr)

                for callstack_key, lst in sorted_smallest_nodes.items():
                    lst_len = len(lst)
                    for i, node in enumerate(lst):
                        if i == lst_len - 1:
                            break
                        next_node = lst[i + 1]
                        if node.addr <= next_node.addr < node.addr + node.size:
                            # umm, those nodes are overlapping, but they must have different end addresses
                            nodekey_a = node.addr + node.size, callstack_key
                            nodekey_b = next_node.addr + next_node.size, callstack_key
                            if nodekey_a == nodekey_b:
                                # error handling: this will only happen if we have completely overlapping nodes
                                # caused by different jumps (one of the jumps is probably incorrect), which usually
                                # indicates an error in CFG recovery. we print a warning and skip this node
                                l.warning("Found completely overlapping nodes %s. It usually indicates an error in CFG "
                                          "recovery. Skip.", node)
                                continue

                            if nodekey_a in smallest_nodes and nodekey_b in smallest_nodes:
                                # misuse end_addresses_to_nodes
                                end_addresses_to_nodes[(node.addr + node.size, callstack_key)].add(node)
                                end_addresses_to_nodes[(node.addr + node.size, callstack_key)].add(next_node)

                            smallest_nodes.pop(nodekey_a, None)
                            smallest_nodes.pop(nodekey_b, None)

        self._normalized = True

Response: Normalizes the CFG making sure that there are no overlapping basic blocks.


Instruction:
Create a Python 3 function to
return a list of all functions that have finished analysis.

Response:
def _get_finished_functions(self):
        """
        Obtain all functions of which we have finished analyzing. As _jobs_to_analyze_per_function is a defaultdict(),
        if a function address shows up in it with an empty job list, we consider we have exhausted all jobs of this
        function (both current jobs and pending jobs), thus the analysis of this function is done.

        :return: a list of function addresses of that we have finished analysis.
        :rtype:  list
        """

        finished_func_addrs = [ ]
        for func_addr, all_jobs in self._jobs_to_analyze_per_function.items():
            if not all_jobs:
                # great! we have finished analyzing this function!
                finished_func_addrs.append(func_addr)

        return finished_func_addrs


Instruction:
Given the following Python 3 function, write the documentation
def _cleanup_analysis_jobs(self, finished_func_addrs=None):

        if finished_func_addrs is None:
            finished_func_addrs = self._get_finished_functions()

        for func_addr in finished_func_addrs:
            if func_addr in self._jobs_to_analyze_per_function:
                del self._jobs_to_analyze_per_function[func_addr]

Response: This function is called by _get_finished_functions to remove all functions of which we have finished analysis.


Instruction:
Write a Python 3 script for
filling in self. _completed_functions list and clean up job manager.

Response:
def _make_completed_functions(self):
        """
        Fill in self._completed_functions list and clean up job manager.

        :return: None
        """

        finished = self._get_finished_functions()
        for func_addr in finished:
            self._completed_functions.add(func_addr)
        self._cleanup_analysis_jobs(finished_func_addrs=finished)


Instruction:
Can you implement a function in Python 3 that
removes all function alignments.

Response:
def remove_function_alignments(self):
        """
        Remove all function alignments.

        :return: None
        """

        # This function requires Capstone engine support
        if not self.project.arch.capstone_support:
            return

        for func_addr in self.kb.functions.keys():
            function = self.kb.functions[func_addr]
            if function.is_simprocedure or function.is_syscall:
                continue
            if len(function.block_addrs_set) == 1:
                block = next((b for b in function.blocks), None)
                if block is None:
                    continue
                if all(self._is_noop_insn(insn) for insn in block.capstone.insns):
                    # remove this function
                    l.debug('Function chunk %#x is used as function alignments. Removing it.', func_addr)
                    del self.kb.functions[func_addr]


Instruction:
Given the following Python 3 function, write the documentation
def make_functions(self):

        # TODO: Is it required that PLT stubs are always aligned by 16? If so, on what architectures and platforms is it
        # TODO:  enforced?

        tmp_functions = self.kb.functions.copy()

        for function in tmp_functions.values():
            function.mark_nonreturning_calls_endpoints()

        # Clear old functions dict
        self.kb.functions.clear()

        blockaddr_to_function = { }
        traversed_cfg_nodes = set()

        function_nodes = set()

        # Find nodes for beginnings of all functions
        for _, dst, data in self.graph.edges(data=True):
            jumpkind = data.get('jumpkind', "")
            if jumpkind == 'Ijk_Call' or jumpkind.startswith('Ijk_Sys'):
                function_nodes.add(dst)

        entry_node = self.model.get_any_node(self._binary.entry)
        if entry_node is not None:
            function_nodes.add(entry_node)

        # aggressively remove and merge functions
        # For any function, if there is a call to it, it won't be removed
        called_function_addrs = { n.addr for n in function_nodes }

        removed_functions_a = self._process_irrational_functions(tmp_functions,
                                                                 called_function_addrs,
                                                                 blockaddr_to_function
                                                                 )
        removed_functions_b, adjusted_cfgnodes = self._process_irrational_function_starts(tmp_functions,
                                                                                called_function_addrs,
                                                                                blockaddr_to_function
                                                                                )
        removed_functions = removed_functions_a | removed_functions_b

        # Remove all nodes that are adjusted
        function_nodes.difference_update(adjusted_cfgnodes)
        for n in self.graph.nodes():
            if n.addr in tmp_functions or n.addr in removed_functions:
                function_nodes.add(n)

        # traverse the graph starting from each node, not following call edges
        # it's important that we traverse all functions in order so that we have a greater chance to come across
        # rational functions before its irrational counterparts (e.g. due to failed jump table resolution)

        min_stage_2_progress = 50.0
        max_stage_2_progress = 90.0
        nodes_count = len(function_nodes)
        for i, fn in enumerate(sorted(function_nodes, key=lambda n: n.addr)):

            if self._low_priority:
                self._release_gil(i, 20)

            if self._show_progressbar or self._progress_callback:
                progress = min_stage_2_progress + (max_stage_2_progress - min_stage_2_progress) * (i * 1.0 / nodes_count)
                self._update_progress(progress)

            self._graph_bfs_custom(self.graph, [ fn ], self._graph_traversal_handler, blockaddr_to_function,
                                   tmp_functions, traversed_cfg_nodes
                                   )

        # Don't forget those small function chunks that are not called by anything.
        # There might be references to them from data, or simply references that we cannot find via static analysis

        secondary_function_nodes = set()
        # add all function chunks ("functions" that are not called from anywhere)
        for func_addr in tmp_functions:
            node = self.model.get_any_node(func_addr)
            if node is None:
                continue
            if node.addr not in blockaddr_to_function:
                secondary_function_nodes.add(node)

        missing_cfg_nodes = set(self.graph.nodes()) - traversed_cfg_nodes
        missing_cfg_nodes = { node for node in missing_cfg_nodes if node.function_address is not None }
        if missing_cfg_nodes:
            l.debug('%d CFGNodes are missing in the first traversal.', len(missing_cfg_nodes))
            secondary_function_nodes |=  missing_cfg_nodes

        min_stage_3_progress = 90.0
        max_stage_3_progress = 99.9

        nodes_count = len(secondary_function_nodes)
        for i, fn in enumerate(sorted(secondary_function_nodes, key=lambda n: n.addr)):

            if self._show_progressbar or self._progress_callback:
                progress = min_stage_3_progress + (max_stage_3_progress - min_stage_3_progress) * (i * 1.0 / nodes_count)
                self._update_progress(progress)

            self._graph_bfs_custom(self.graph, [fn], self._graph_traversal_handler, blockaddr_to_function,
                                   tmp_functions
                                   )

        to_remove = set()

        # Remove all stubs after PLT entries
        if not is_arm_arch(self.project.arch):
            for fn in self.kb.functions.values():
                addr = fn.addr - (fn.addr % 16)
                if addr != fn.addr and addr in self.kb.functions and self.kb.functions[addr].is_plt:
                    to_remove.add(fn.addr)

        # remove empty functions
        for func in self.kb.functions.values():
            if func.startpoint is None:
                to_remove.add(func.addr)

        for addr in to_remove:
            del self.kb.functions[addr]

        # Update CFGNode.function_address
        for node in self._nodes.values():
            if node.addr in blockaddr_to_function:
                node.function_address = blockaddr_to_function[node.addr].addr

Response: Revisit the entire control flow graph and create Function instances accordingly.


Instruction:
Given the following Python 3 function, write the documentation
def _process_irrational_functions(self, functions, predetermined_function_addrs, blockaddr_to_function):

        functions_to_remove = { }

        functions_can_be_removed = set(functions.keys()) - set(predetermined_function_addrs)

        for func_addr, function in functions.items():

            if func_addr in functions_to_remove:
                continue

            # check all blocks and see if any block ends with an indirect jump and is not resolved
            has_unresolved_jumps = False
            # the functions to merge with must be locating between the unresolved basic block address and the endpoint
            # of the current function
            max_unresolved_jump_addr = 0
            for block_addr in function.block_addrs_set:
                if block_addr in self.indirect_jumps and \
                        self.indirect_jumps[block_addr].jumpkind == 'Ijk_Boring' and \
                        not self.indirect_jumps[block_addr].resolved_targets:
                    # it's not resolved
                    # we should also make sure it's a jump, not a call
                    has_unresolved_jumps = True
                    max_unresolved_jump_addr = max(max_unresolved_jump_addr, block_addr)

            if not has_unresolved_jumps:
                continue

            if function.startpoint is None:
                continue

            startpoint_addr = function.startpoint.addr
            if not function.endpoints:
                # Function should have at least one endpoint
                continue
            endpoint_addr = max([ a.addr for a in function.endpoints ])
            the_endpoint = next(a for a in function.endpoints if a.addr == endpoint_addr)
            endpoint_addr += the_endpoint.size

            # sanity check: startpoint of the function should be greater than its endpoint
            if startpoint_addr >= endpoint_addr:
                continue
            if max_unresolved_jump_addr <= startpoint_addr or max_unresolved_jump_addr >= endpoint_addr:
                continue

            # scan forward from the endpoint to include any function tail jumps
            # Here is an example:
            # loc_8049562:
            #       mov eax, ebp
            #       add esp, 3ch
            #       ...
            #       ret
            # loc_804956c:
            #       mov ebp, 3
            #       jmp loc_8049562
            # loc_8049573:
            #       mov ebp, 4
            #       jmp loc_8049562
            #
            last_addr = endpoint_addr
            tmp_state = self.project.factory.blank_state(mode='fastpath')
            while True:
                try:
                    # using successors is slow, but acceptable since we won't be creating millions of blocks here...
                    tmp_state.ip = last_addr
                    b = self.project.factory.successors(tmp_state, jumpkind='Ijk_Boring')
                    if len(b.successors) != 1:
                        break
                    if b.successors[0].history.jumpkind not in ('Ijk_Boring', 'Ijk_InvalICache'):
                        break
                    if b.successors[0].ip.symbolic:
                        break
                    suc_addr = b.successors[0].ip._model_concrete
                    if max(startpoint_addr, the_endpoint.addr - 0x40) <= suc_addr < the_endpoint.addr + the_endpoint.size:
                        # increment the endpoint_addr
                        endpoint_addr = b.addr + b.artifacts['irsb_size']
                    else:
                        break

                    last_addr = b.addr + b.artifacts['irsb_size']

                except (SimTranslationError, SimMemoryError, SimIRSBError, SimEngineError):
                    break

            # find all functions that are between [ startpoint, endpoint ]

            should_merge = True
            functions_to_merge = set()
            for f_addr in functions_can_be_removed:
                f = functions[f_addr]
                if f_addr == func_addr:
                    continue
                if max_unresolved_jump_addr < f_addr < endpoint_addr and \
                        all([max_unresolved_jump_addr < b_addr < endpoint_addr for b_addr in f.block_addrs]):
                    if f_addr in functions_to_remove:
                        # this function has already been merged with other functions before... it cannot be merged with
                        # this function anymore
                        should_merge = False
                        break
                    if f_addr in predetermined_function_addrs:
                        # this function is a legit one. it shouldn't be removed/merged
                        should_merge = False
                        break
                    functions_to_merge.add(f_addr)

            if not should_merge:
                # we shouldn't merge...
                continue

            for f_addr in functions_to_merge:
                functions_to_remove[f_addr] = func_addr

        # merge all functions
        for to_remove, merge_with in functions_to_remove.items():
            func_merge_with = self._addr_to_function(merge_with, blockaddr_to_function, functions)

            for block_addr in functions[to_remove].block_addrs:
                blockaddr_to_function[block_addr] = func_merge_with

            del functions[to_remove]

        return set(functions_to_remove.keys())

Response: This method is used to remove functions that are not in the function manager and add them to the function manager.


Instruction:
Can you create a Python 3 function that
functions that are identified via function prologues can be starting after the actual beginning of the function. For example, the following function (with an incorrect start) might exist after a CFG recovery: sub_8049f70: push esi sub_8049f71: sub esp, 0A8h mov esi, [esp+0ACh+arg_0] mov [esp+0ACh+var_88], 0 If the following conditions are met, we will remove the second function and merge it into the first function: - The second function is not called by other code. - The first function has only one jumpout site, which points to the second function. - The first function and the second function are adjacent. :param FunctionManager functions: All functions that angr recovers. :return: A set of addresses of all removed functions. :rtype: set

Response:
def _process_irrational_function_starts(self, functions, predetermined_function_addrs, blockaddr_to_function):
        """
        Functions that are identified via function prologues can be starting after the actual beginning of the function.
        For example, the following function (with an incorrect start) might exist after a CFG recovery:

        sub_8049f70:
          push    esi

        sub_8049f71:
          sub     esp, 0A8h
          mov     esi, [esp+0ACh+arg_0]
          mov     [esp+0ACh+var_88], 0

        If the following conditions are met, we will remove the second function and merge it into the first function:
        - The second function is not called by other code.
        - The first function has only one jumpout site, which points to the second function.
        - The first function and the second function are adjacent.

        :param FunctionManager functions:   All functions that angr recovers.
        :return:                            A set of addresses of all removed functions.
        :rtype:                             set
        """

        addrs = sorted(k for k in functions.keys()
                       if not self.project.is_hooked(k) and not self.project.simos.is_syscall_addr(k))
        functions_to_remove = set()
        adjusted_cfgnodes = set()

        for addr_0, addr_1 in zip(addrs[:-1], addrs[1:]):
            if addr_1 in predetermined_function_addrs:
                continue

            func_0 = functions[addr_0]

            if len(func_0.block_addrs) == 1:
                block = next(func_0.blocks)
                if block.vex.jumpkind not in ('Ijk_Boring', 'Ijk_InvalICache'):
                    continue
                # Skip alignment blocks
                if self._is_noop_block(self.project.arch, block):
                    continue

                target = block.vex.next
                if isinstance(target, pyvex.IRExpr.Const):  # pylint: disable=unidiomatic-typecheck
                    target_addr = target.con.value
                elif type(target) in (pyvex.IRConst.U16, pyvex.IRConst.U32, pyvex.IRConst.U64):  # pylint: disable=unidiomatic-typecheck
                    target_addr = target.value
                elif type(target) is int:  # pylint: disable=unidiomatic-typecheck
                    target_addr = target
                else:
                    continue

                if target_addr != addr_1:
                    continue

                cfgnode_0 = self.model.get_any_node(addr_0)
                cfgnode_1 = self.model.get_any_node(addr_1)

                # Are func_0 adjacent to func_1?
                if cfgnode_0.addr + cfgnode_0.size != addr_1:
                    continue

                # Merge block addr_0 and block addr_1
                l.debug("Merging function %#x into %#x.", addr_1, addr_0)
                self._merge_cfgnodes(cfgnode_0, cfgnode_1)
                adjusted_cfgnodes.add(cfgnode_0)
                adjusted_cfgnodes.add(cfgnode_1)

                # Merge it
                func_1 = functions[addr_1]
                for block_addr in func_1.block_addrs:
                    if block_addr == addr_1:
                        # Skip addr_1 (since it has been merged to the preceding block)
                        continue
                    merge_with = self._addr_to_function(addr_0, blockaddr_to_function, functions)
                    blockaddr_to_function[block_addr] = merge_with

                functions_to_remove.add(addr_1)

        for to_remove in functions_to_remove:
            del functions[to_remove]

        return functions_to_remove, adjusted_cfgnodes


Instruction:
Implement a Python 3 function for
converting an address to a Function object and store the mapping between the block addresses to the function object.

Response:
def _addr_to_function(self, addr, blockaddr_to_function, known_functions):
        """
        Convert an address to a Function object, and store the mapping in a dict. If the block is known to be part of a
        function, just return that function.

        :param int addr: Address to convert
        :param dict blockaddr_to_function: A mapping between block addresses to Function instances.
        :param angr.knowledge_plugins.FunctionManager known_functions: Recovered functions.
        :return: a Function object
        :rtype: angr.knowledge.Function
        """

        if addr in blockaddr_to_function:
            f = blockaddr_to_function[addr]
        else:
            is_syscall = self.project.simos.is_syscall_addr(addr)

            n = self.model.get_any_node(addr, is_syscall=is_syscall)
            if n is None: node = addr
            else: node = self._to_snippet(n)

            if isinstance(addr, SootAddressDescriptor):
                addr = addr.method

            self.kb.functions._add_node(addr, node, syscall=is_syscall)
            f = self.kb.functions.function(addr=addr)

            blockaddr_to_function[addr] = f

            function_is_returning = False
            if addr in known_functions:
                if known_functions.function(addr).returning:
                    f.returning = True
                    function_is_returning = True

            if not function_is_returning:
                # We will rerun function feature analysis on this function later. Add it to
                # self._updated_nonreturning_functions so it can be picked up by function feature analysis later.
                if self._updated_nonreturning_functions is not None:
                    self._updated_nonreturning_functions.add(addr)

        return f


Instruction:
Write a Python 3 function that can
check if the source and destination nodes are tail - call optimizations.

Response:
def _is_tail_call_optimization(self, g : networkx.DiGraph, src_addr, dst_addr, src_function, all_edges,
                                   known_functions, blockaddr_to_function):
        """
        If source and destination belong to the same function, and the following criteria apply:
        - source node has only one default exit
        - destination is not one of the known functions
        - destination does not belong to another function, or destination belongs to the same function that
          source belongs to
        - at the end of the block, the SP offset is 0
        - for all other edges that are pointing to the destination node, their source nodes must only have one default
          exit, too

        :return:    True if it is a tail-call optimization. False otherwise.
        :rtype:     bool
        """

        def _has_more_than_one_exit(node_):
            return len(g.out_edges(node_)) > 1

        if len(all_edges) == 1 and dst_addr != src_addr:
            the_edge = next(iter(all_edges))
            _, dst, data = the_edge
            if data.get('stmt_idx', None) != DEFAULT_STATEMENT:
                return False

            dst_in_edges = g.in_edges(dst, data=True)
            if len(dst_in_edges) > 1:
                # there are other edges going to the destination node. check all edges to make sure all source nodes
                # only have one default exit
                if any(data.get('stmt_idx', None) != DEFAULT_STATEMENT for _, _, data in dst_in_edges):
                    # some nodes are jumping to the destination node via non-default edges. skip.
                    return False
                if any(_has_more_than_one_exit(src_) for src_, _, _ in dst_in_edges):
                    # at least one source node has more than just the default exit. skip.
                    return False

            candidate = False
            if dst_addr in known_functions:
                # dst_addr cannot be the same as src_function.addr. Pass
                pass
            elif dst_addr in blockaddr_to_function:
                # it seems that we already know where this function should belong to. Pass.
                dst_func = blockaddr_to_function[dst_addr]
                if dst_func is src_function:
                    # they belong to the same function right now, but they'd better not
                    candidate = True
                    # treat it as a tail-call optimization
            else:
                # we don't know where it belongs to
                # treat it as a tail-call optimization
                candidate = True

            if candidate:
                regs = {self.project.arch.sp_offset}
                if hasattr(self.project.arch, 'bp_offset') and self.project.arch.bp_offset is not None:
                    regs.add(self.project.arch.bp_offset)
                sptracker = self.project.analyses.StackPointerTracker(src_function, regs, track_memory=self._sp_tracking_track_memory)
                sp_delta = sptracker.offset_after_block(src_addr, self.project.arch.sp_offset)
                if sp_delta == 0:
                    return True

        return False


Instruction:
Explain what the following Python 3 code does
def _graph_traversal_handler(self, g, src, dst, data, blockaddr_to_function, known_functions, all_edges):

        src_addr = src.addr
        src_function = self._addr_to_function(src_addr, blockaddr_to_function, known_functions)

        if src_addr not in src_function.block_addrs_set:
            n = self.model.get_any_node(src_addr)
            if n is None: node = src_addr
            else: node = self._to_snippet(n)
            self.kb.functions._add_node(src_function.addr, node)

        if data is None:
            # it's a single node only
            return

        jumpkind = data['jumpkind']

        if jumpkind == 'Ijk_Ret':
            n = self.model.get_any_node(src_addr)
            if n is None: from_node = src_addr
            else: from_node = self._to_snippet(n)
            self.kb.functions._add_return_from(src_function.addr, from_node, None)

        if dst is None:
            return

        dst_addr = dst.addr

        # get instruction address and statement index
        ins_addr = data.get('ins_addr', None)
        stmt_idx = data.get('stmt_idx', None)

        if jumpkind == 'Ijk_Call' or jumpkind.startswith('Ijk_Sys'):

            is_syscall = jumpkind.startswith('Ijk_Sys')

            # It must be calling a function
            dst_function = self._addr_to_function(dst_addr, blockaddr_to_function, known_functions)

            n = self.model.get_any_node(src_addr)
            if n is None: src_snippet = self._to_snippet(addr=src_addr, base_state=self._base_state)
            else:
                src_snippet = self._to_snippet(cfg_node=n)

            # HACK: FIXME: We need a better way of representing unresolved calls and whether they return.
            # For now, assume UnresolvedTarget returns if we're calling to it

            # If the function doesn't return, don't add a fakeret!
            if not all_edges or (dst_function.returning is False and not dst_function.name == 'UnresolvableCallTarget'):
                fakeret_node = None
            else:
                fakeret_node = self._one_fakeret_node(all_edges)

            if fakeret_node is None:
                fakeret_snippet = None
            else:
                fakeret_snippet = self._to_snippet(cfg_node=fakeret_node)

            if isinstance(dst_addr, SootAddressDescriptor):
                dst_addr = dst_addr.method

            self.kb.functions._add_call_to(src_function.addr, src_snippet, dst_addr, fakeret_snippet, syscall=is_syscall,
                                           ins_addr=ins_addr, stmt_idx=stmt_idx)

            if dst_function.returning:
                returning_target = src.addr + src.size
                if returning_target not in blockaddr_to_function:
                    if returning_target not in known_functions:
                        blockaddr_to_function[returning_target] = src_function
                    else:
                        self._addr_to_function(returning_target, blockaddr_to_function, known_functions)

                to_outside = not blockaddr_to_function[returning_target] is src_function

                n = self.model.get_any_node(returning_target)
                if n is None:
                    returning_snippet = self._to_snippet(addr=returning_target, base_state=self._base_state)
                else:
                    returning_snippet = self._to_snippet(cfg_node=n)

                self.kb.functions._add_fakeret_to(src_function.addr, src_snippet, returning_snippet, confirmed=True,
                                                  to_outside=to_outside
                                                  )

        elif jumpkind in ('Ijk_Boring', 'Ijk_InvalICache'):

            # convert src_addr and dst_addr to CodeNodes
            n = self.model.get_any_node(src_addr)
            if n is None: src_node = src_addr
            else: src_node = self._to_snippet(cfg_node=n)

            n = self.model.get_any_node(dst_addr)
            if n is None: dst_node = dst_addr
            else: dst_node = self._to_snippet(cfg_node=n)

            # pre-check: if source and destination do not belong to the same section, it must be jumping to another
            # function
            belong_to_same_section = self._addrs_belong_to_same_section(src_addr, dst_addr)
            if not belong_to_same_section:
                _ = self._addr_to_function(dst_addr, blockaddr_to_function, known_functions)

            if self._detect_tail_calls:
                if self._is_tail_call_optimization(g, src_addr, dst_addr, src_function, all_edges, known_functions,
                                                   blockaddr_to_function):
                    l.debug("Possible tail-call optimization detected at function %#x.", dst_addr)
                    # it's (probably) a tail-call optimization. we should make the destination node a new function
                    # instead.
                    blockaddr_to_function.pop(dst_addr, None)
                    _ = self._addr_to_function(dst_addr, blockaddr_to_function, known_functions)
                    self.kb.functions._add_outside_transition_to(src_function.addr, src_node, dst_node,
                                                                 to_function_addr=dst_addr
                                                                 )

            # is it a jump to another function?
            if isinstance(dst_addr, SootAddressDescriptor):
                is_known_function_addr = dst_addr.method in known_functions and dst_addr.method.addr == dst_addr
            else:
                is_known_function_addr = dst_addr in known_functions

            if is_known_function_addr or (
                dst_addr in blockaddr_to_function and blockaddr_to_function[dst_addr] is not src_function
            ):
                # yes it is
                dst_function_addr = blockaddr_to_function[dst_addr].addr if dst_addr in blockaddr_to_function else \
                    dst_addr

                self.kb.functions._add_outside_transition_to(src_function.addr, src_node, dst_node,
                                                             to_function_addr=dst_function_addr
                                                             )

                _ = self._addr_to_function(dst_addr, blockaddr_to_function, known_functions)
            else:
                # no it's not
                # add the transition code

                if dst_addr not in blockaddr_to_function:
                    blockaddr_to_function[dst_addr] = src_function

                self.kb.functions._add_transition_to(src_function.addr, src_node, dst_node, ins_addr=ins_addr,
                                                     stmt_idx=stmt_idx
                                                     )

        elif jumpkind == 'Ijk_FakeRet':

            # convert src_addr and dst_addr to CodeNodes
            n = self.model.get_any_node(src_addr)
            if n is None:
                src_node = src_addr
            else:
                src_node = self._to_snippet(n)

            n = self.model.get_any_node(dst_addr)
            if n is None:
                dst_node = dst_addr
            else:
                dst_node = self._to_snippet(n)

            if dst_addr not in blockaddr_to_function:
                if isinstance(dst_addr, SootAddressDescriptor):
                    if dst_addr.method not in known_functions:
                        blockaddr_to_function[dst_addr] = src_function
                        target_function = src_function
                    else:
                        target_function = self._addr_to_function(dst_addr, blockaddr_to_function, known_functions)
                else:
                    if dst_addr not in known_functions:
                        blockaddr_to_function[dst_addr] = src_function
                        target_function = src_function
                    else:
                        target_function = self._addr_to_function(dst_addr, blockaddr_to_function, known_functions)
            else:
                target_function = blockaddr_to_function[dst_addr]

            # Figure out if the function called (not the function returned to) returns.
            # We may have determined that this does not happen, since the time this path
            # was scheduled for exploration
            called_function = None
            # Try to find the call that this fakeret goes with
            for _, d, e in all_edges:
                if e['jumpkind'] == 'Ijk_Call':
                    if d.addr in blockaddr_to_function:
                        called_function = blockaddr_to_function[d.addr]
                        break
            # We may have since figured out that the called function doesn't ret.
            # It's important to assume that all unresolved targets do return
            if called_function is not None and \
                    called_function.returning is False:
                return

            to_outside = not target_function is src_function

            # FIXME: Not sure we should confirm this fakeret or not.
            self.kb.functions._add_fakeret_to(src_function.addr, src_node, dst_node, confirmed=True,
                                              to_outside=to_outside, to_function_addr=target_function.addr
                                              )

        else:
            l.debug('Ignored jumpkind %s', jumpkind)

Response: This function is called by the function manager when a CFG is traversed. It creates new functions or adds nodes to existing functions accordingly.


Instruction:
Can you implement a function in Python 3 that
checks if the block is a no - op block by checking VEX statements.

Response:
def _is_noop_block(arch, block):
        """
        Check if the block is a no-op block by checking VEX statements.

        :param block: The VEX block instance.
        :return: True if the entire block is a single-byte or multi-byte nop instruction, False otherwise.
        :rtype: bool
        """

        if arch.name == "MIPS32":
            if arch.memory_endness == "Iend_BE":
                MIPS32_BE_NOOPS = {
                    b"\x00\x20\x08\x25",  # move $at, $at
                }
                insns = set(block.bytes[i:i+4] for i in range(0, block.size, 4))
                if MIPS32_BE_NOOPS.issuperset(insns):
                    return True

        # Fallback
        # the block is a noop block if it only has IMark statements

        if all((type(stmt) is pyvex.IRStmt.IMark) for stmt in block.vex.statements):
            return True
        return False


Instruction:
Can you generate the documentation for the following Python 3 function
def _is_noop_insn(insn):

        if insn.insn_name() == 'nop':
            # nops
            return True
        if insn.insn_name() == 'lea':
            # lea reg, [reg + 0]
            op0, op1 = insn.operands
            if op0.type == 1 and op1.type == 3:
                # reg and mem
                if op0.reg == op1.mem.base and op1.mem.index == 0 and op1.mem.disp == 0:
                    return True

        # add more types of no-op instructions here :-)

        return False

Response: Check if the instruction does nothing.


Instruction:
Can you generate the documentation for the following Python 3 function
def _get_nop_length(cls, insns):

        nop_length = 0

        if insns and cls._is_noop_insn(insns[0]):
            # see where those nop instructions terminate
            for insn in insns:
                if cls._is_noop_insn(insn):
                    nop_length += insn.size
                else:
                    break

        return nop_length

Response: Calculate the total length of leading nop instructions.


Instruction:
Given the following Python 3 function, write the documentation
def _lift(self, *args, **kwargs):
        if 'backup_state' not in kwargs:
            kwargs['backup_state'] = self._base_state
        return self.project.factory.block(*args, **kwargs)

Response: Internal helper to create a basic block of code.


Instruction:
How would you explain what the following Python 3 function does
def _resolve_indirect_jump_timelessly(self, addr, block, func_addr, jumpkind):

        if block.statements is None:
            block = self.project.factory.block(block.addr, size=block.size).vex

        for res in self.timeless_indirect_jump_resolvers:
            if res.filter(self, addr, func_addr, block, jumpkind):
                r, resolved_targets = res.resolve(self, addr, func_addr, block, jumpkind)
                if r:
                    return True, resolved_targets
        return False, [ ]

Response: Checks if MIPS32 and calls MIPS32 check otherwise false


Instruction:
Write a Python 3 function that can
call when an indirect jump is successfully resolved.

Response:
def _indirect_jump_resolved(self, jump, jump_addr, resolved_by, targets):
        """
        Called when an indirect jump is successfully resolved.

        :param IndirectJump jump:                   The resolved indirect jump, or None if an IndirectJump instance is
                                                    not available.
        :param int jump_addr:                       Address of the resolved indirect jump.
        :param IndirectJumpResolver resolved_by:    The resolver used to resolve this indirect jump.
        :param list targets:                        List of indirect jump targets.
        :param CFGJob job:                          The job at the start of the block containing the indirect jump.

        :return: None
        """

        addr = jump.addr if jump is not None else jump_addr
        l.debug('The indirect jump at %#x is successfully resolved by %s. It has %d targets.', addr, resolved_by, len(targets))
        self.kb.resolved_indirect_jumps.add(addr)


Instruction:
Explain what the following Python 3 code does
def _indirect_jump_unresolved(self, jump):

        l.debug('Failed to resolve the indirect jump at %#x.', jump.addr)
        # tell KnowledgeBase that it's not resolved
        # TODO: self.kb._unresolved_indirect_jumps is not processed during normalization. Fix it.
        self.kb.unresolved_indirect_jumps.add(jump.addr)

Response: Called when we cannot resolve an indirect jump.


Instruction:
Create a Python 3 function for
calling when an indirect jump is encountered.

Response:
def _indirect_jump_encountered(self, addr, cfg_node, irsb, func_addr, stmt_idx=DEFAULT_STATEMENT):
        """
        Called when we encounter an indirect jump. We will try to resolve this indirect jump using timeless (fast)
        indirect jump resolvers. If it cannot be resolved, we will see if this indirect jump has been resolved before.

        :param int addr:                Address of the block containing the indirect jump.
        :param cfg_node:                The CFGNode instance of the block that contains the indirect jump.
        :param pyvex.IRSB irsb:         The IRSB instance of the block that contains the indirect jump.
        :param int func_addr:           Address of the current function.
        :param int or str stmt_idx:     ID of the source statement.

        :return:    A 3-tuple of (whether it is resolved or not, all resolved targets, an IndirectJump object
                    if there is one or None otherwise)
        :rtype:     tuple
        """

        jumpkind = irsb.jumpkind
        l.debug('(%s) IRSB %#x has an indirect jump as its default exit.', jumpkind, addr)

        # try resolving it fast
        resolved, resolved_targets = self._resolve_indirect_jump_timelessly(addr, irsb, func_addr, jumpkind)
        if resolved:
            return True, resolved_targets, None

        # Add it to our set. Will process it later if user allows.
        # Create an IndirectJump instance
        if addr not in self.indirect_jumps:
            if self.project.arch.branch_delay_slot:
                ins_addr = cfg_node.instruction_addrs[-2]
            else:
                ins_addr = cfg_node.instruction_addrs[-1]
            ij = IndirectJump(addr, ins_addr, func_addr, jumpkind, stmt_idx, resolved_targets=[])
            self.indirect_jumps[addr] = ij
            resolved = False
        else:
            ij = self.indirect_jumps[addr]  # type: IndirectJump
            resolved = len(ij.resolved_targets) > 0

        return resolved, ij.resolved_targets, ij


Instruction:
Make a summary of the following Python 3 code
def _process_unresolved_indirect_jumps(self):

        l.info("%d indirect jumps to resolve.", len(self._indirect_jumps_to_resolve))

        all_targets = set()
        for idx, jump in enumerate(self._indirect_jumps_to_resolve):  # type:int,IndirectJump
            if self._low_priority:
                self._release_gil(idx, 20, 0.0001)
            all_targets |= self._process_one_indirect_jump(jump)

        self._indirect_jumps_to_resolve.clear()

        return all_targets

Response: Resolves unresolved indirect jumps in previous scanning.


Instruction:
Implement a function in Python 3 to
resolve a given indirect jump.

Response:
def _process_one_indirect_jump(self, jump):
        """
        Resolve a given indirect jump.

        :param IndirectJump jump:  The IndirectJump instance.
        :return:        A set of resolved indirect jump targets (ints).
        """

        resolved = False
        resolved_by = None
        targets = None

        block = self._lift(jump.addr, opt_level=1)

        for resolver in self.indirect_jump_resolvers:
            resolver.base_state = self._base_state

            if not resolver.filter(self, jump.addr, jump.func_addr, block, jump.jumpkind):
                continue

            resolved, targets = resolver.resolve(self, jump.addr, jump.func_addr, block, jump.jumpkind)
            if resolved:
                resolved_by = resolver
                break

        if resolved:
            self._indirect_jump_resolved(jump, jump.addr, resolved_by, targets)
        else:
            self._indirect_jump_unresolved(jump)

        return set() if targets is None else set(targets)


Instruction:
Explain what the following Python 3 code does
def resolve(self, cfg, addr, func_addr, block, jumpkind):
        project = self.project  # short-hand
        self._max_targets = cfg._indirect_jump_target_limit

        # Perform a backward slicing from the jump target
        b = Blade(cfg.graph, addr, -1,
            cfg=cfg, project=project,
            ignore_sp=False, ignore_bp=False,
            max_level=3, base_state=self.base_state)

        stmt_loc = (addr, DEFAULT_STATEMENT)
        if stmt_loc not in b.slice:
            return False, None

        load_stmt_loc, load_stmt, load_size = None, None, None
        stmts_to_remove = [stmt_loc]
        stmts_adding_base_addr = [ ]  # type: list[JumpTargetBaseAddr]
        # All temporary variables that hold indirect addresses loaded out of the memory
        # Obviously, load_stmt.tmp must be here
        # if there are additional data transferring statements between the Load statement and the base-address-adding
        # statement, all_addr_holders will have more than one temporary variables
        #
        # Here is an example:
        #
        # IRSB 0x4c64c4
        #  + 06 | t12 = LDle:I32(t7)
        #  + 07 | t11 = 32Sto64(t12)
        #  + 10 | t2 = Add64(0x0000000000571df0,t11)
        #
        # all_addr_holders will be {(0x4c64c4, 11): AddressTransferringTypes.SignedExtension32to64,
        #           (0x4c64c4, 12); AddressTransferringTypes.Assignment,
        #           }
        all_addr_holders = OrderedDict()

        while True:
            preds = list(b.slice.predecessors(stmt_loc))
            if len(preds) != 1:
                return False, None
            block_addr, stmt_idx = stmt_loc = preds[0]
            block = project.factory.block(block_addr, backup_state=self.base_state).vex
            stmt = block.statements[stmt_idx]
            if isinstance(stmt, (pyvex.IRStmt.WrTmp, pyvex.IRStmt.Put)):
                if isinstance(stmt.data, (pyvex.IRExpr.Get, pyvex.IRExpr.RdTmp)):
                    # data transferring
                    stmts_to_remove.append(stmt_loc)
                    if isinstance(stmt, pyvex.IRStmt.WrTmp):
                        all_addr_holders[(stmt_loc[0], stmt.tmp)] = AddressTransferringTypes.Assignment
                    continue
                elif isinstance(stmt.data, pyvex.IRExpr.ITE):
                    # data transferring
                    #   t16 = if (t43) ILGop_Ident32(LDle(t29)) else 0x0000c844
                    # > t44 = ITE(t43,t16,0x0000c844)
                    stmts_to_remove.append(stmt_loc)
                    if isinstance(stmt, pyvex.IRStmt.WrTmp):
                        all_addr_holders[(stmt_loc[0], stmt.tmp)] = AddressTransferringTypes.Assignment
                    continue
                elif isinstance(stmt.data, pyvex.IRExpr.Unop):
                    if stmt.data.op == 'Iop_32Sto64':
                        # data transferring with conversion
                        # t11 = 32Sto64(t12)
                        stmts_to_remove.append(stmt_loc)
                        if isinstance(stmt, pyvex.IRStmt.WrTmp):
                            all_addr_holders[(stmt_loc[0], stmt.tmp)] = AddressTransferringTypes.SignedExtension32to64
                        continue
                    elif stmt.data.op == 'Iop_64to32':
                        # data transferring with conversion
                        # t24 = 64to32(t21)
                        stmts_to_remove.append(stmt_loc)
                        if isinstance(stmt, pyvex.IRStmt.WrTmp):
                            all_addr_holders[(stmt_loc[0], stmt.tmp)] = AddressTransferringTypes.Truncation64to32
                        continue
                    elif stmt.data.op == 'Iop_32Uto64':
                        # data transferring with conversion
                        # t21 = 32Uto64(t22)
                        stmts_to_remove.append(stmt_loc)
                        if isinstance(stmt, pyvex.IRStmt.WrTmp):
                            all_addr_holders[(stmt_loc[0], stmt.tmp)] = AddressTransferringTypes.UnsignedExtension32to64
                        continue
                elif isinstance(stmt.data, pyvex.IRExpr.Binop) and stmt.data.op.startswith('Iop_Add'):
                    # GitHub issue #1289, a S390X binary
                    # jump_label = &jump_table + *(jump_table[index])
                    #       IRSB 0x4007c0
                    #   00 | ------ IMark(0x4007c0, 4, 0) ------
                    # + 01 | t0 = GET:I32(212)
                    # + 02 | t1 = Add32(t0,0xffffffff)
                    #   03 | PUT(352) = 0x0000000000000003
                    #   04 | t13 = 32Sto64(t0)
                    #   05 | t6 = t13
                    #   06 | PUT(360) = t6
                    #   07 | PUT(368) = 0xffffffffffffffff
                    #   08 | PUT(376) = 0x0000000000000000
                    #   09 | PUT(212) = t1
                    #   10 | PUT(ia) = 0x00000000004007c4
                    #   11 | ------ IMark(0x4007c4, 6, 0) ------
                    # + 12 | t14 = 32Uto64(t1)
                    # + 13 | t8 = t14
                    # + 14 | t16 = CmpLE64U(t8,0x000000000000000b)
                    # + 15 | t15 = 1Uto32(t16)
                    # + 16 | t10 = t15
                    # + 17 | t11 = CmpNE32(t10,0x00000000)
                    # + 18 | if (t11) { PUT(offset=336) = 0x4007d4; Ijk_Boring }
                    #   Next: 0x4007ca
                    #
                    #       IRSB 0x4007d4
                    #   00 | ------ IMark(0x4007d4, 6, 0) ------
                    # + 01 | t8 = GET:I64(r2)
                    # + 02 | t7 = Shr64(t8,0x3d)
                    # + 03 | t9 = Shl64(t8,0x03)
                    # + 04 | t6 = Or64(t9,t7)
                    # + 05 | t11 = And64(t6,0x00000007fffffff8)
                    #   06 | ------ IMark(0x4007da, 6, 0) ------
                    #   07 | PUT(r1) = 0x0000000000400a50
                    #   08 | PUT(ia) = 0x00000000004007e0
                    #   09 | ------ IMark(0x4007e0, 6, 0) ------
                    # + 10 | t12 = Add64(0x0000000000400a50,t11)
                    # + 11 | t16 = LDbe:I64(t12)
                    #   12 | PUT(r2) = t16
                    #   13 | ------ IMark(0x4007e6, 4, 0) ------
                    # + 14 | t17 = Add64(0x0000000000400a50,t16)
                    # + Next: t17
                    #
                    # Special case: a base address is added to the loaded offset before jumping to it.
                    if isinstance(stmt.data.args[0], pyvex.IRExpr.Const) and \
                            isinstance(stmt.data.args[1], pyvex.IRExpr.RdTmp):
                        stmts_adding_base_addr.append(JumpTargetBaseAddr(stmt_loc, stmt,
                                                                         stmt.data.args[1].tmp,
                                                                         base_addr=stmt.data.args[0].con.value)
                                                      )
                        stmts_to_remove.append(stmt_loc)
                    elif isinstance(stmt.data.args[0], pyvex.IRExpr.RdTmp) and \
                            isinstance(stmt.data.args[1], pyvex.IRExpr.Const):
                        stmts_adding_base_addr.append(JumpTargetBaseAddr(stmt_loc, stmt,
                                                                         stmt.data.args[0].tmp,
                                                                         base_addr=stmt.data.args[1].con.value)
                                                      )
                        stmts_to_remove.append(stmt_loc)
                    elif isinstance(stmt.data.args[0], pyvex.IRExpr.RdTmp) and \
                            isinstance(stmt.data.args[1], pyvex.IRExpr.RdTmp):
                        # one of the tmps must be holding a concrete value at this point
                        stmts_adding_base_addr.append(JumpTargetBaseAddr(stmt_loc, stmt,
                                                                         stmt.data.args[0].tmp,
                                                                         tmp_1=stmt.data.args[1].tmp)
                                                      )
                        stmts_to_remove.append(stmt_loc)
                    else:
                        # not supported
                        pass
                    continue
                elif isinstance(stmt.data, pyvex.IRExpr.Load):
                    # Got it!
                    load_stmt, load_stmt_loc, load_size = stmt, stmt_loc, \
                                                          block.tyenv.sizeof(stmt.tmp) // self.project.arch.byte_width
                    stmts_to_remove.append(stmt_loc)
            elif isinstance(stmt, pyvex.IRStmt.LoadG):
                # Got it!
                #
                # this is how an ARM jump table is translated to VEX
                # > t16 = if (t43) ILGop_Ident32(LDle(t29)) else 0x0000c844
                load_stmt, load_stmt_loc, load_size = stmt, stmt_loc, \
                                                      block.tyenv.sizeof(stmt.dst) // self.project.arch.byte_width
                stmts_to_remove.append(stmt_loc)

            break

        if load_stmt_loc is None:
            # the load statement is not found
            return False, None

        # If we're just reading a constant, don't bother with the rest of this mess!
        if isinstance(load_stmt, pyvex.IRStmt.WrTmp):
            if type(load_stmt.data.addr) is pyvex.IRExpr.Const:
                # It's directly loading from a constant address
                # e.g.,
                #  ldr r0, =main+1
                #  blx r0
                # It's not a jump table, but we resolve it anyway
                jump_target_addr = load_stmt.data.addr.con.value
                jump_target = cfg._fast_memory_load_pointer(jump_target_addr)
                if jump_target is None:
                    l.info("Constant indirect jump at %#08x points outside of loaded memory to %#08x", addr, jump_target_addr)
                    return False, None
                l.info("Resolved constant indirect jump from %#08x to %#08x", addr, jump_target_addr)
                ij = cfg.indirect_jumps[addr]
                ij.jumptable = False
                ij.resolved_targets = set([jump_target])
                return True, [jump_target]
        elif isinstance(load_stmt, pyvex.IRStmt.LoadG):
            if type(load_stmt.addr) is pyvex.IRExpr.Const:
                # It's directly loading from a constant address
                # e.g.,
                #  4352c     SUB     R1, R11, #0x1000
                #  43530     LDRHI   R3, =loc_45450
                #  ...
                #  43540     MOV     PC, R3
                #
                # It's not a jump table, but we resolve it anyway
                # Note that this block has two branches: One goes to 45450, the other one goes to whatever the original
                # value of R3 is. Some intensive data-flow analysis is required in this case.
                jump_target_addr = load_stmt.addr.con.value
                jump_target = cfg._fast_memory_load_pointer(jump_target_addr)
                l.info("Resolved constant indirect jump from %#08x to %#08x", addr, jump_target_addr)
                ij = cfg.indirect_jumps[addr]
                ij.jumptable = False
                ij.resolved_targets = set([jump_target])
                return True, [jump_target]
        # Well, we have a real jumptable to resolve!

        # If we're just reading a constant, don't bother with the rest of this mess!
        if isinstance(load_stmt, pyvex.IRStmt.WrTmp):
            if type(load_stmt.data.addr) is pyvex.IRExpr.Const:
                # It's directly loading from a constant address
                # e.g.,
                #  ldr r0, =main+1
                #  blx r0
                # It's not a jump table, but we resolve it anyway
                jump_target_addr = load_stmt.data.addr.con.value
                jump_target = cfg._fast_memory_load_pointer(jump_target_addr)
                if not jump_target:
                    #...except this constant looks like a jumpout!
                    l.info("Constant indirect jump directed out of the binary at #%08x", addr)
                    return False, []
                l.info("Resolved constant indirect jump from %#08x to %#08x", addr, jump_target_addr)
                ij = cfg.indirect_jumps[addr]
                ij.jumptable = False
                ij.resolved_targets = set([jump_target])
                return True, [jump_target]
        elif isinstance(load_stmt, pyvex.IRStmt.LoadG):
            if type(load_stmt.addr) is pyvex.IRExpr.Const:
                # It's directly loading from a constant address
                # e.g.,
                #  4352c     SUB     R1, R11, #0x1000
                #  43530     LDRHI   R3, =loc_45450
                #  ...
                #  43540     MOV     PC, R3
                #
                # It's not a jump table, but we resolve it anyway
                # Note that this block has two branches: One goes to 45450, the other one goes to whatever the original
                # value of R3 is. Some intensive data-flow analysis is required in this case.
                jump_target_addr = load_stmt.addr.con.value
                jump_target = cfg._fast_memory_load_pointer(jump_target_addr)
                l.info("Resolved constant indirect jump from %#08x to %#08x", addr, jump_target_addr)
                ij = cfg.indirect_jumps[addr]
                ij.jumptable = False
                ij.resolved_targets = set([jump_target])
                return True, [jump_target]
        # skip all statements before the load statement
        # We want to leave the final loaded value as symbolic, so we can
        # get the full range of possibilities
        b.slice.remove_nodes_from(stmts_to_remove)

        # Debugging output
        if l.level == logging.DEBUG:
            self._dbg_repr_slice(b)

        # Get all sources
        sources = [ n_ for n_ in b.slice.nodes() if b.slice.in_degree(n_) == 0 ]

        # Create the annotated CFG
        annotatedcfg = AnnotatedCFG(project, None, detect_loops=False)
        annotatedcfg.from_digraph(b.slice)

        # pylint: disable=too-many-nested-blocks
        for src_irsb, _ in sources:
            # Use slicecutor to execute each one, and get the address
            # We simply give up if any exception occurs on the way
            start_state = self._initial_state(src_irsb)
            # Keep IP symbolic to avoid unnecessary concretization
            start_state.options.add(o.KEEP_IP_SYMBOLIC)
            start_state.options.add(o.NO_IP_CONCRETIZATION)
            # be quiet!!!!!!
            start_state.options.add(o.SYMBOL_FILL_UNCONSTRAINED_REGISTERS)
            start_state.options.add(o.SYMBOL_FILL_UNCONSTRAINED_MEMORY)

            # any read from an uninitialized segment should be unconstrained
            if self._bss_regions:
                bss_memory_read_bp = BP(when=BP_BEFORE, enabled=True, action=self._bss_memory_read_hook)
                start_state.inspect.add_breakpoint('mem_read', bss_memory_read_bp)

            # FIXME:
            # this is a hack: for certain architectures, we do not initialize the base pointer, since the jump table on
            # those architectures may use the bp register to store value
            if not self.project.arch.name in {'S390X'}:
                start_state.regs.bp = start_state.arch.initial_sp + 0x2000

            self._cached_memread_addrs.clear()
            init_registers_on_demand_bp = BP(when=BP_BEFORE, enabled=True, action=self._init_registers_on_demand)
            start_state.inspect.add_breakpoint('mem_read', init_registers_on_demand_bp)

            # Create the slicecutor
            simgr = self.project.factory.simulation_manager(start_state, resilience=True)
            slicecutor = Slicecutor(annotatedcfg, force_taking_exit=True)
            simgr.use_technique(slicecutor)
            simgr.use_technique(Explorer(find=load_stmt_loc[0]))

            # Run it!
            try:
                simgr.run()
            except KeyError as ex:
                # This is because the program slice is incomplete.
                # Blade will support more IRExprs and IRStmts
                l.debug("KeyError occurred due to incomplete program slice.", exc_info=ex)
                continue

            # Get the jumping targets
            for r in simgr.found:
                try:
                    whitelist = annotatedcfg.get_whitelisted_statements(r.addr)
                    last_stmt = annotatedcfg.get_last_statement_index(r.addr)
                    succ = project.factory.successors(r, whitelist=whitelist, last_stmt=last_stmt)
                except (AngrError, SimError):
                    # oops there are errors
                    l.warning('Cannot get jump successor states from a path that has reached the target. Skip it.')
                    continue
                all_states = succ.flat_successors + succ.unconstrained_successors
                if not all_states:
                    l.warning("Slicecutor failed to execute the program slice. No output state is available.")
                    continue

                state = all_states[0]  # Just take the first state
                self._cached_memread_addrs.clear()  # clear the cache to save some memory (and avoid confusion when
                                                    # debugging)

                # Parse the memory load statement and get the memory address of where the jump table is stored
                jumptable_addr = self._parse_load_statement(load_stmt, state)
                if jumptable_addr is None:
                    continue

                # sanity check and necessary pre-processing
                if stmts_adding_base_addr:
                    assert len(stmts_adding_base_addr) == 1  # Making sure we are only dealing with one operation here
                    jump_base_addr = stmts_adding_base_addr[0]
                    if jump_base_addr.base_addr_available:
                        addr_holders = { (jump_base_addr.stmt_loc[0], jump_base_addr.tmp) }
                    else:
                        addr_holders = { (jump_base_addr.stmt_loc[0], jump_base_addr.tmp),
                                         (jump_base_addr.stmt_loc[0], jump_base_addr.tmp_1)
                                         }
                    if len(set(all_addr_holders.keys()).intersection(addr_holders)) != 1:
                        # for some reason it's trying to add a base address onto a different temporary variable that we
                        # are not aware of. skip.
                        continue

                    if not jump_base_addr.base_addr_available:
                        # we need to decide which tmp is the address holder and which tmp holds the base address
                        addr_holder = next(iter(set(all_addr_holders.keys()).intersection(addr_holders)))
                        if jump_base_addr.tmp_1 == addr_holder[1]:
                            # swap the two tmps
                            jump_base_addr.tmp, jump_base_addr.tmp_1 = jump_base_addr.tmp_1, jump_base_addr.tmp
                        # Load the concrete base address
                        jump_base_addr.base_addr = state.solver.eval(state.scratch.temps[jump_base_addr.tmp_1])

                all_targets = [ ]
                total_cases = jumptable_addr._model_vsa.cardinality

                if total_cases > self._max_targets:
                    # We resolved too many targets for this indirect jump. Something might have gone wrong.
                    l.debug("%d targets are resolved for the indirect jump at %#x. It may not be a jump table. Try the "
                            "next source, if there is any.",
                            total_cases, addr)
                    continue

                    # Or alternatively, we can ask user, which is meh...
                    #
                    # jump_base_addr = int(raw_input("please give me the jump base addr: "), 16)
                    # total_cases = int(raw_input("please give me the total cases: "))
                    # jump_target = state.solver.SI(bits=64, lower_bound=jump_base_addr, upper_bound=jump_base_addr +
                    # (total_cases - 1) * 8, stride=8)

                jump_table = [ ]

                min_jumptable_addr = state.solver.min(jumptable_addr)
                max_jumptable_addr = state.solver.max(jumptable_addr)

                # Both the min jump target and the max jump target should be within a mapped memory region
                # i.e., we shouldn't be jumping to the stack or somewhere unmapped
                if (not project.loader.find_segment_containing(min_jumptable_addr) or
                        not project.loader.find_segment_containing(max_jumptable_addr)):
                    if (not project.loader.find_section_containing(min_jumptable_addr) or
                            not project.loader.find_section_containing(max_jumptable_addr)):

                        l.debug("Jump table %#x might have jump targets outside mapped memory regions. "
                                "Continue to resolve it from the next data source.", addr)
                        continue

                # Load the jump table from memory
                for idx, a in enumerate(state.solver.eval_upto(jumptable_addr, total_cases)):
                    if idx % 100 == 0 and idx != 0:
                        l.debug("%d targets have been resolved for the indirect jump at %#x...", idx, addr)
                    target = cfg._fast_memory_load_pointer(a, size=load_size)
                    all_targets.append(target)

                # Adjust entries inside the jump table
                if stmts_adding_base_addr:
                    stmt_adding_base_addr = stmts_adding_base_addr[0]
                    base_addr = stmt_adding_base_addr.base_addr
                    conversion_ops = list(reversed(list(v for v in all_addr_holders.values()
                                                   if v is not AddressTransferringTypes.Assignment)))
                    if conversion_ops:
                        invert_conversion_ops = [ ]
                        for conversion_op in conversion_ops:
                            if conversion_op is AddressTransferringTypes.SignedExtension32to64:
                                lam = lambda a: (a | 0xffffffff00000000) if a >= 0x80000000 else a
                            elif conversion_op is AddressTransferringTypes.UnsignedExtension32to64:
                                lam = lambda a: a
                            elif conversion_op is AddressTransferringTypes.Truncation64to32:
                                lam = lambda a: a & 0xffffffff
                            else:
                                raise NotImplementedError("Unsupported conversion operation.")
                            invert_conversion_ops.append(lam)
                        all_targets_copy = all_targets
                        all_targets = [ ]
                        for target_ in all_targets_copy:
                            for lam in invert_conversion_ops:
                                target_ = lam(target_)
                            all_targets.append(target_)
                    mask = (2 ** self.project.arch.bits) - 1
                    all_targets = [(target + base_addr) & mask for target in all_targets]

                # Finally... all targets are ready
                illegal_target_found = False
                for target in all_targets:
                    # if the total number of targets is suspicious (it usually implies a failure in applying the
                    # constraints), check if all jump targets are legal
                    if len(all_targets) in {0x100, 0x10000} and not self._is_jumptarget_legal(target):
                        l.info("Jump target %#x is probably illegal. Try to resolve indirect jump at %#x from the next "
                               "source.", target, addr)
                        illegal_target_found = True
                        break
                    jump_table.append(target)
                if illegal_target_found:
                    continue

                l.info("Resolved %d targets from %#x.", len(all_targets), addr)

                # write to the IndirectJump object in CFG
                ij = cfg.indirect_jumps[addr]
                if total_cases > 1:
                    # It can be considered a jump table only if there are more than one jump target
                    ij.jumptable = True
                    ij.jumptable_addr = state.solver.min(jumptable_addr)
                    ij.resolved_targets = set(jump_table)
                    ij.jumptable_entries = jump_table
                else:
                    ij.jumptable = False
                    ij.resolved_targets = set(jump_table)

                return True, all_targets

        l.info("Could not resolve indirect jump %#x in funtion %#x.", addr, func_addr)
        return False, None

Response: Resolves indirect jump tables.


Instruction:
Explain what the following Python 3 code does
def _parse_load_statement(load_stmt, state):

        # The jump table address is stored in a tmp. In this case, we find the jump-target loading tmp.
        load_addr_tmp = None

        if isinstance(load_stmt, pyvex.IRStmt.WrTmp):
            if type(load_stmt.data.addr) is pyvex.IRExpr.RdTmp:
                load_addr_tmp = load_stmt.data.addr.tmp
            elif type(load_stmt.data.addr) is pyvex.IRExpr.Const:
                # It's directly loading from a constant address
                # e.g.,
                #  ldr r0, =main+1
                #  blx r0
                # It's not a jump table, but we resolve it anyway
                jump_target_addr = load_stmt.data.addr.con.value
                return state.solver.BVV(jump_target_addr, state.arch.bits)
        elif isinstance(load_stmt, pyvex.IRStmt.LoadG):
            if type(load_stmt.addr) is pyvex.IRExpr.RdTmp:
                load_addr_tmp = load_stmt.addr.tmp
            elif type(load_stmt.addr) is pyvex.IRExpr.Const:
                # It's directly loading from a constant address
                # e.g.,
                #  4352c     SUB     R1, R11, #0x1000
                #  43530     LDRHI   R3, =loc_45450
                #  ...
                #  43540     MOV     PC, R3
                #
                # It's not a jump table, but we resolve it anyway
                # Note that this block has two branches: One goes to 45450, the other one goes to whatever the original
                # value of R3 is. Some intensive data-flow analysis is required in this case.
                jump_target_addr = load_stmt.addr.con.value
                return state.solver.BVV(jump_target_addr, state.arch.bits)
        else:
            raise TypeError("Unsupported address loading statement type %s." % type(load_stmt))

        if state.scratch.temps[load_addr_tmp] is None:
            # the tmp variable is not there... umm...
            return None

        jump_addr = state.scratch.temps[load_addr_tmp]

        if isinstance(load_stmt, pyvex.IRStmt.LoadG):
            # LoadG comes with a guard. We should apply this guard to the load expression
            guard_tmp = load_stmt.guard.tmp
            guard = state.scratch.temps[guard_tmp] != 0
            try:
                jump_addr = state.memory._apply_condition_to_symbolic_addr(jump_addr, guard)
            except Exception: # pylint: disable=broad-except
                l.exception("Error computing jump table address!")
                return None
        return jump_addr

Response: Parse a memory load statement and return the jump target addresses.


Instruction:
Can you implement a function in Python 3 that
searches the segment list for the entry that the address addr belongs to and returns the offset of that segment.

Response:
def _search(self, addr):
        """
        Checks which segment that the address `addr` should belong to, and, returns the offset of that segment.
        Note that the address may not actually belong to the block.

        :param addr: The address to search
        :return: The offset of the segment.
        """

        start = 0
        end = len(self._list)

        while start != end:
            mid = (start + end) // 2

            segment = self._list[mid]
            if addr < segment.start:
                end = mid
            elif addr >= segment.end:
                start = mid + 1
            else:
                # Overlapped :(
                start = mid
                break

        return start


Instruction:
Explain what the following Python 3 code does
def _insert_and_merge(self, address, size, sort, idx):

        # sanity check
        if idx > 0 and address + size <= self._list[idx - 1].start:
            # There is a bug, since _list[idx] must be the closest one that is less than the current segment
            l.warning("BUG FOUND: new segment should always be greater than _list[idx].")
            # Anyways, let's fix it.
            self._insert_and_merge(address, size, sort, idx - 1)
            return

        # Insert the block first
        # The new block might be overlapping with other blocks. _insert_and_merge_core will fix the overlapping.
        if idx == len(self._list):
            self._list.append(Segment(address, address + size, sort))
        else:
            self._list.insert(idx, Segment(address, address + size, sort))
        # Apparently _bytes_occupied will be wrong if the new block overlaps with any existing block. We will fix it
        # later
        self._bytes_occupied += size

        # Search forward to merge blocks if necessary
        pos = idx
        while pos < len(self._list):
            merged, pos, bytes_change = self._insert_and_merge_core(pos, "forward")

            if not merged:
                break

            self._bytes_occupied += bytes_change

        # Search backward to merge blocks if necessary
        if pos >= len(self._list):
            pos = len(self._list) - 1

        while pos > 0:
            merged, pos, bytes_change = self._insert_and_merge_core(pos, "backward")

            if not merged:
                break

            self._bytes_occupied += bytes_change

Response: Insert a new entry into the internal list and merge it with the other entries.


Instruction:
How would you explain what the following Python 3 function does
def _dbg_output(self):
        s = "["
        lst = []
        for segment in self._list:
            lst.append(repr(segment))
        s += ", ".join(lst)
        s += "]"
        return s

Response: Returns a string representation of the segments that form this SegmentList


Instruction:
How would you code a function in Python 3 to
check that all segments with same sort do not overlap with the same start and end.

Response:
def _debug_check(self):
        """
        Iterates over list checking segments with same sort do not overlap

        :raise: Exception: if segments overlap space with same sort
        """
        # old_start = 0
        old_end = 0
        old_sort = ""
        for segment in self._list:
            if segment.start <= old_end and segment.sort == old_sort:
                raise AngrCFGError("Error in SegmentList: blocks are not merged")
            # old_start = start
            old_end = segment.end
            old_sort = segment.sort


Instruction:
Explain what the following Python 3 code does
def next_free_pos(self, address):

        idx = self._search(address)
        if idx < len(self._list) and self._list[idx].start <= address < self._list[idx].end:
            # Occupied
            i = idx
            while i + 1 < len(self._list) and self._list[i].end == self._list[i + 1].start:
                i += 1
            if i == len(self._list):
                return self._list[-1].end

            return self._list[i].end

        return address

Response: Returns the next free position with respect to an address including that address itself


Instruction:
Can you generate a brief explanation for the following Python 3 code
def next_pos_with_sort_not_in(self, address, sorts, max_distance=None):

        list_length = len(self._list)

        idx = self._search(address)
        if idx < list_length:
            # Occupied
            block = self._list[idx]

            if max_distance is not None and address + max_distance < block.start:
                return None

            if block.start <= address < block.end:
                # the address is inside the current block
                if block.sort not in sorts:
                    return address
                # tick the idx forward by 1
                idx += 1

            i = idx
            while i < list_length:
                if max_distance is not None and address + max_distance < self._list[i].start:
                    return None
                if self._list[i].sort not in sorts:
                    return self._list[i].start
                i += 1

        return None

Response: Returns the next position in the list that is not in the specified sort list.


Instruction:
Write a Python 3 script for
checking if an address belongs to any segment in the cache.

Response:
def is_occupied(self, address):
        """
        Check if an address belongs to any segment

        :param address: The address to check
        :return: True if this address belongs to a segment, False otherwise
        """

        idx = self._search(address)
        if len(self._list) <= idx:
            return False
        if self._list[idx].start <= address < self._list[idx].end:
            return True
        if idx > 0 and address < self._list[idx - 1].end:
            # TODO: It seems that this branch is never reached. Should it be removed?
            return True
        return False


Instruction:
Can you generate the documentation for the following Python 3 function
def occupied_by_sort(self, address):

        idx = self._search(address)
        if len(self._list) <= idx:
            return None
        if self._list[idx].start <= address < self._list[idx].end:
            return self._list[idx].sort
        if idx > 0 and address < self._list[idx - 1].end:
            # TODO: It seems that this branch is never reached. Should it be removed?
            return self._list[idx - 1].sort
        return None

Response: Checks if an address belongs to any segment and returns the sort of the segment that occupies this address


Instruction:
Implement a Python 3 function for
adding a block to the segment list.

Response:
def occupy(self, address, size, sort):
        """
        Include a block, specified by (address, size), in this segment list.

        :param int address:     The starting address of the block.
        :param int size:        Size of the block.
        :param str sort:        Type of the block.
        :return: None
        """

        if size is None or size <= 0:
            # Cannot occupy a non-existent block
            return

        # l.debug("Occpuying 0x%08x-0x%08x", address, address + size)
        if not self._list:
            self._list.append(Segment(address, address + size, sort))
            self._bytes_occupied += size
            return
        # Find adjacent element in our list
        idx = self._search(address)
        # print idx

        self._insert_and_merge(address, size, sort, idx)


Instruction:
Make a summary of the following Python 3 code
def copy(self):
        n = SegmentList()

        n._list = [ a.copy() for a in self._list ]
        n._bytes_occupied = self._bytes_occupied
        return n

Response: Make a copy of the SegmentList instance.


Instruction:
How would you explain what the following Python 3 function does
def _analyze_function(self):

        if not self._function.is_simprocedure \
                and not self._function.is_plt \
                and not self._variable_manager.has_function_manager(self._function.addr):
            l.warning("Please run variable recovery on %s before analyzing its calling conventions.",
                      repr(self._function))
            return None

        vm = self._variable_manager[self._function.addr]

        input_variables = vm.input_variables()

        input_args = self._args_from_vars(input_variables)

        # TODO: properly decide sp_delta
        sp_delta = self.project.arch.bytes if self.project.arch.call_pushes_ret else 0

        cc = SimCC.find_cc(self.project.arch, list(input_args), sp_delta)

        if cc is None:
            l.warning('_analyze_function(): Cannot find a calling convention that fits the given arguments.')

        return cc

Response: Return the calling convention that this function is in.


Instruction:
Can you write a function in Python 3 where it
tests if the given variable is a sane register variable.

Response:
def _is_sane_register_variable(self, variable):
        """
        Filters all registers that are surly not members of function arguments.
        This can be seen as a workaround, since VariableRecoveryFast sometimes gives input variables of cc_ndep (which
        is a VEX-specific register) :-(

        :param SimRegisterVariable variable: The variable to test.
        :return:                             True if it is an acceptable function argument, False otherwise.
        :rtype:                              bool
        """

        arch = self.project.arch

        if arch.name == 'AARCH64':
            return 16 <= variable.reg < 80  # x0-x7

        elif arch.name == 'AMD64':
            return (24 <= variable.reg < 40 or  # rcx, rdx
                    64 <= variable.reg < 104 or  # rsi, rdi, r8, r9, r10
                    224 <= variable.reg < 480)  # xmm0-xmm7

        elif is_arm_arch(arch):
            return 8 <= variable.reg < 24  # r0-r3

        elif arch.name == 'MIPS32':
            return 24 <= variable.reg < 40  # a0-a3

        elif arch.name == 'PPC32':
            return 28 <= variable.reg < 60  # r3-r10

        elif arch.name == 'X86':
            return (8 <= variable.reg < 24 or  # eax, ebx, ecx, edx
                    160 <= variable.reg < 288)  # xmm0-xmm7

        else:
            l.critical('Unsupported architecture %s.', arch.name)
            return True


Instruction:
Can you generate a brief explanation for the following Python 3 code
def copy(self):
        o = SimLibrary()
        o.procedures = dict(self.procedures)
        o.non_returning = set(self.non_returning)
        o.prototypes = dict(self.prototypes)
        o.default_ccs = dict(self.default_ccs)
        o.names = list(self.names)
        return o

Response: Make a copy of this SimLibrary allowing it to be mutated without affecting the global version.


Instruction:
Given the following Python 3 function, write the documentation
def update(self, other):
        self.procedures.update(other.procedures)
        self.non_returning.update(other.non_returning)
        self.prototypes.update(other.prototypes)
        self.default_ccs.update(other.default_ccs)

Response: Augment this SimLibrary with the information from another SimLibrary.


Instruction:
Write a Python 3 script to
set some common names of this library by which it may be referred during linking.

Response:
def set_library_names(self, *names):
        """
        Set some common names of this library by which it may be referred during linking

        :param names:   Any number of string library names may be passed as varargs.
        """
        for name in names:
            self.names.append(name)
            SIM_LIBRARIES[name] = self


Instruction:
Can you generate a brief explanation for the following Python 3 code
def set_default_cc(self, arch_name, cc_cls):
        arch_name = archinfo.arch_from_id(arch_name).name
        self.default_ccs[arch_name] = cc_cls

Response: Set the default calling convention used for this library under a given architecture


Instruction:
Write a Python 3 function for
setting the prototype of a function in the form of a C - style function declaration.

Response:
def set_c_prototype(self, c_decl):
        """
        Set the prototype of a function in the form of a C-style function declaration.

        :param str c_decl: The C-style declaration of the function.
        :return:           A tuple of (function name, function prototype)
        :rtype:            tuple
        """

        parsed = parse_file(c_decl)
        parsed_decl = parsed[0]
        if not parsed_decl:
            raise ValueError('Cannot parse the function prototype.')
        func_name, func_proto = next(iter(parsed_decl.items()))

        self.set_prototype(func_name, func_proto)

        return func_name, func_proto


Instruction:
Make a summary of the following Python 3 code
def add(self, name, proc_cls, **kwargs):
        self.procedures[name] = proc_cls(display_name=name, **kwargs)

Response: Adds a function implementation to the library.


Instruction:
Can you generate the documentation for the following Python 3 function
def add_all_from_dict(self, dictionary, **kwargs):
        for name, procedure in dictionary.items():
            self.add(name, procedure, **kwargs)

Response: Adds all the classes in the given dictionary to the library.


Instruction:
Can you generate the documentation for the following Python 3 function
def add_alias(self, name, *alt_names):
        old_procedure = self.procedures[name]
        for alt in alt_names:
            new_procedure = copy.deepcopy(old_procedure)
            new_procedure.display_name = alt
            self.procedures[alt] = new_procedure

Response: Add some duplicate names for a given function.


Instruction:
Create a Python 3 function for
getting an implementation of the given function specialized for the given arch or a stub procedure if none exists.

Response:
def get(self, name, arch):
        """
        Get an implementation of the given function specialized for the given arch, or a stub procedure if none exists.

        :param name:    The name of the function as a string
        :param arch:    The architecure to use, as either a string or an archinfo.Arch instance
        :return:        A SimProcedure instance representing the function as found in the library
        """
        if type(arch) is str:
            arch = archinfo.arch_from_id(arch)
        if name in self.procedures:
            proc = copy.deepcopy(self.procedures[name])
            self._apply_metadata(proc, arch)
            return proc
        else:
            return self.get_stub(name, arch)


Instruction:
Can you tell what is the following Python 3 function doing
def get_stub(self, name, arch):
        proc = self.fallback_proc(display_name=name, is_stub=True)
        self._apply_metadata(proc, arch)
        return proc

Response: Returns a SimProcedure instance representing a stub for the given function.


Instruction:
Can you generate a brief explanation for the following Python 3 code
def has_metadata(self, name):
        return self.has_implementation(name) or \
            name in self.non_returning or \
            name in self.prototypes

Response: Check if a function has either an implementation or any metadata associated with it.


Instruction:
Make a summary of the following Python 3 code
def minimum_syscall_number(self, abi):
        if abi not in self.syscall_number_mapping or \
                not self.syscall_number_mapping[abi]:
            return 0
        return min(self.syscall_number_mapping[abi])

Response: Returns the smallest syscall number known for the given abi


Instruction:
Create a Python 3 function for
returning the maximum syscall number known for the given abi

Response:
def maximum_syscall_number(self, abi):
        """
        :param abi: The abi to evaluate
        :return:    The largest syscall number known for the given abi
        """
        if abi not in self.syscall_number_mapping or \
                not self.syscall_number_mapping[abi]:
            return 0
        return max(self.syscall_number_mapping[abi])


Instruction:
Explain what the following Python 3 code does
def add_number_mapping(self, abi, number, name):
        self.syscall_number_mapping[abi][number] = name
        self.syscall_name_mapping[abi][name] = number

Response: Associate a syscall number with the name of a function present in the underlying library.


Instruction:
Can you implement a function in Python 3 that
adds a dictionary mapping syscall numbers to names of functions present in the underlying library.

Response:
def add_number_mapping_from_dict(self, abi, mapping):
        """
        Batch-associate syscall numbers with names of functions present in the underlying SimLibrary

        :param abi:     The abi for which this mapping applies
        :param mapping: A dict mapping syscall numbers to function names
        """
        self.syscall_number_mapping[abi].update(mapping)
        self.syscall_name_mapping[abi].update(dict(reversed(i) for i in mapping.items()))


Instruction:
How would you implement a function in Python 3 that
returns a SimProcedure representing a plausable stub that could model the syscall.

Response:
def get_stub(self, number, arch, abi_list=()):
        """
        Pretty much the intersection of SimLibrary.get_stub() and SimSyscallLibrary.get().

        :param number:      The syscall number
        :param arch:        The architecture being worked with, as either a string name or an archinfo.Arch
        :param abi_list:    A list of ABI names that could be used
        :return:            A SimProcedure representing a plausable stub that could model the syscall
        """
        name, arch, abi = self._canonicalize(number, arch, abi_list)
        proc = super(SimSyscallLibrary, self).get_stub(name, arch)
        self._apply_numerical_metadata(proc, number, arch, abi)
        l.debug("unsupported syscall: %s", number)
        return proc


Instruction:
How would you explain what the following Python 3 function does
def has_implementation(self, number, arch, abi_list=()):
        name, _, _ = self._canonicalize(number, arch, abi_list)
        return super(SimSyscallLibrary, self).has_implementation(name)

Response: A method to check if a syscall has an implementation of the given number arch and abi_list.


Instruction:
Implement a Python 3 function for
returning the Claripy expression of a VEX temp value.

Response:
def tmp_expr(self, tmp):
        """
        Returns the Claripy expression of a VEX temp value.

        :param tmp: the number of the tmp
        :param simplify: simplify the tmp before returning it
        :returns: a Claripy expression of the tmp
        """
        self.state._inspect('tmp_read', BP_BEFORE, tmp_read_num=tmp)
        try:
            v = self.temps[tmp]
            if v is None:
                raise SimValueError('VEX temp variable %d does not exist. This is usually the result of an incorrect '
                                    'slicing.' % tmp)
        except IndexError:
            raise SimValueError("Accessing a temp that is illegal in this tyenv")
        self.state._inspect('tmp_read', BP_AFTER, tmp_read_expr=v)
        return v


Instruction:
Given the following Python 3 function, write the documentation
def store_tmp(self, tmp, content, reg_deps=None, tmp_deps=None, deps=None):
        self.state._inspect('tmp_write', BP_BEFORE, tmp_write_num=tmp, tmp_write_expr=content)
        tmp = self.state._inspect_getattr('tmp_write_num', tmp)
        content = self.state._inspect_getattr('tmp_write_expr', content)

        if o.SYMBOLIC_TEMPS not in self.state.options:
            # Non-symbolic
            self.temps[tmp] = content
        else:
            # Symbolic
            self.state.add_constraints(self.temps[tmp] == content)

        # get the size, and record the write
        if o.TRACK_TMP_ACTIONS in self.state.options:
            data_ao = SimActionObject(content, reg_deps=reg_deps, tmp_deps=tmp_deps, deps=deps, state=self.state)
            r = SimActionData(self.state, SimActionData.TMP, SimActionData.WRITE, tmp=tmp, data=data_ao, size=content.length)
            self.state.history.add_action(r)

        self.state._inspect('tmp_write', BP_AFTER)

Response: Stores a Claripy expression in a VEX temp value.


Instruction:
Can you write a function in Python 3 where it
takes a path and returns a simple absolute path as a list of directories from the root

Response:
def _normalize_path(self, path):
        """
        Takes a path and returns a simple absolute path as a list of directories from the root
        """
        if type(path) is str:
            path = path.encode()
        path = path.split(b'\0')[0]

        if path[0:1] != self.pathsep:
            path = self.cwd + self.pathsep + path
        keys = path.split(self.pathsep)
        i = 0
        while i < len(keys):
            if keys[i] == b'':
                keys.pop(i)
            elif keys[i] == b'.':
                keys.pop(i)
            elif keys[i] == b'..':
                keys.pop(i)
                if i != 0:
                    keys.pop(i-1)
                    i -= 1
            else:
                i += 1
        return keys


Instruction:
Create a Python 3 function for
changing the current directory to the given path.

Response:
def chdir(self, path):
        """
        Changes the current directory to the given path
        """
        self.cwd = self._join_chunks(self._normalize_path(path))


Instruction:
Can you generate the documentation for the following Python 3 function
def get(self, path):
        mountpoint, chunks = self.get_mountpoint(path)

        if mountpoint is None:
            return self._files.get(self._join_chunks(chunks))
        else:
            return mountpoint.get(chunks)

Response: Get a file from the filesystem. Returns a SimFile or None.


Instruction:
Given the following Python 3 function, write the documentation
def insert(self, path, simfile):
        if self.state is not None:
            simfile.set_state(self.state)
        mountpoint, chunks = self.get_mountpoint(path)

        if mountpoint is None:
            self._files[self._join_chunks(chunks)] = simfile
            return True
        else:
            return mountpoint.insert(chunks, simfile)

Response: Insert a file into the filesystem. Returns whether the operation was successful.


Instruction:
Here you have a function in Python 3, explain what it does
def delete(self, path):
        mountpoint, chunks = self.get_mountpoint(path)
        apath = self._join_chunks(chunks)

        if mountpoint is None:
            try:
                simfile = self._files.pop(apath)
            except KeyError:
                return False
            else:
                self.state.history.add_event('fs_unlink', path=apath, unlink_idx=len(self.unlinks))
                self.unlinks.append((apath, simfile))
                return True
        else:
            return mountpoint.delete(chunks)

Response: Removes a file from the filesystem. Returns whether the operation was successful.


Instruction:
Create a Python 3 function for
adding a mountpoint to the filesystem.

Response:
def mount(self, path, mount):
        """
        Add a mountpoint to the filesystem.
        """
        self._mountpoints[self._join_chunks(self._normalize_path(path))] = mount


Instruction:
How would you code a function in Python 3 to
remove a mountpoint from the filesystem.

Response:
def unmount(self, path):
        """
        Remove a mountpoint from the filesystem.
        """
        del self._mountpoints[self._join_chunks(self._normalize_path(path))]


Instruction:
Here you have a function in Python 3, explain what it does
def get_mountpoint(self, path):
        path_chunks = self._normalize_path(path)
        for i in range(len(path_chunks) - 1, -1, -1):
            partial_path = self._join_chunks(path_chunks[:-i])
            if partial_path in self._mountpoints:
                mountpoint = self._mountpoints[partial_path]
                if mountpoint is None:
                    break
                return mountpoint, path_chunks[-i:]

        return None, path_chunks

Response: Look up the mountpoint servicing the given path.