use std::collections::HashSet;
use crate::{
analysis::dataflow::*,
check::opt::OptCheck,
utils::span::{relative_pos_range, span_to_filename, span_to_line_number, span_to_source_code},
};
use rustc_hir::intravisit;
use rustc_middle::mir::Local;
use rustc_middle::ty::TyCtxt;
use annotate_snippets::{Level, Renderer, Snippet};
use rustc_span::Span;
use super::super::super::loop_visitors::LoopFinder;
use super::super::super::LEVEL;
crate::def_paths! {
vec_new: "std::vec::Vec::new",
vec_push: "std::vec::Vec::push",
vec_with_capacity: "std::vec::Vec::with_capacity",
vec_reserve: "std::vec::Vec::reserve",
}
pub struct UnreservedVecCheck {
record: Vec<Span>,
}
fn is_vec_new_node(node: &GraphNode) -> bool {
for op in node.ops.iter() {
if let NodeOp::Call(def_id) = op {
let def_paths = &DEFPATHS.get().unwrap();
if *def_id == def_paths.vec_new.last_def_id() {
return true;
}
}
}
false
}
fn is_vec_push_node(node: &GraphNode) -> bool {
for op in node.ops.iter() {
if let NodeOp::Call(def_id) = op {
let def_paths = &DEFPATHS.get().unwrap();
if *def_id == def_paths.vec_push.last_def_id() {
return true;
}
}
}
false
}
fn find_upside_reservation(graph: &Graph, node_idx: Local) -> Option<Local> {
let mut reservation_node_idx = None;
let def_paths = &DEFPATHS.get().unwrap();
let mut node_operator = |graph: &Graph, idx: Local| -> DFSStatus {
let node = &graph.nodes[idx];
for op in node.ops.iter() {
if let NodeOp::Call(def_id) = op {
if *def_id == def_paths.vec_with_capacity.last_def_id()
|| *def_id == def_paths.vec_reserve.last_def_id()
{
reservation_node_idx = Some(idx);
return DFSStatus::Stop;
}
}
}
DFSStatus::Continue
};
let mut seen = HashSet::new();
graph.dfs(
node_idx,
Direction::Upside,
&mut node_operator,
&mut Graph::equivalent_edge_validator,
false,
&mut seen,
);
reservation_node_idx
}
impl OptCheck for UnreservedVecCheck {
fn new() -> Self {
Self { record: Vec::new() }
}
fn check(&mut self, graph: &Graph, tcx: &TyCtxt) {
let def_paths = &DEFPATHS.get_or_init(|| DefPaths::new(tcx));
let level = LEVEL.lock().unwrap();
if *level == 2 {
for (node_idx, node) in graph.nodes.iter_enumerated() {
if is_vec_new_node(node) {
self.record.push(node.span);
}
if is_vec_push_node(node) {
if let None = find_upside_reservation(graph, node_idx) {
self.record.push(node.span);
}
}
}
}
let def_id = graph.def_id;
let body = tcx.hir_body_owned_by(def_id.as_local().unwrap());
let typeck_results = tcx.typeck(def_id.as_local().unwrap());
let target_def_id = def_paths.vec_push.last_def_id();
let mut loop_finder = LoopFinder::new(typeck_results, target_def_id);
intravisit::walk_body(&mut loop_finder, body);
for (_, push_record) in loop_finder.into_record() {
for push_span in push_record {
if let Some((node_idx, _)) = graph.query_node_by_span(push_span, false) {
if let None = find_upside_reservation(graph, node_idx) {
self.record.push(push_span);
}
}
}
}
}
fn report(&self, graph: &Graph) {
for span in self.record.iter() {
report_unreserved_vec_bug(graph, *span);
}
}
fn cnt(&self) -> usize {
self.record.len()
}
}
fn report_unreserved_vec_bug(graph: &Graph, span: Span) {
let code_source = span_to_source_code(graph.span);
let filename = span_to_filename(span);
let snippet: Snippet<'_> = Snippet::source(&code_source)
.line_start(span_to_line_number(graph.span))
.origin(&filename)
.fold(true)
.annotation(
Level::Error
.span(relative_pos_range(graph.span, span))
.label("Space unreserved."),
);
let message = Level::Warning
.title("Improper data collection detected")
.snippet(snippet)
.footer(Level::Help.title("Reserve enough space."));
let renderer = Renderer::styled();
rap_warn!("{}", renderer.render(message));
}