use std::collections::HashSet;
use crate::{
analysis::{
core::dataflow::{graph::*, *},
opt::OptCheck,
utils::def_path::DefPath,
},
utils::log::{relative_pos_range, span_to_filename, span_to_line_number, span_to_source_code},
};
use once_cell::sync::OnceCell;
use rustc_middle::{mir::Local, ty::TyCtxt};
use annotate_snippets::{Level, Renderer, Snippet};
use rustc_span::Span;
static DEFPATHS: OnceCell<DefPaths> = OnceCell::new();
use super::super::super::LEVEL;
use rustc_hir::{Expr, ExprKind, intravisit};
use rustc_middle::ty::TypeckResults;
struct DefPaths {
vec_new: DefPath,
vec_push: DefPath,
vec_with_capacity: DefPath,
vec_reserve: DefPath,
}
impl DefPaths {
pub fn new(tcx: &TyCtxt<'_>) -> Self {
Self {
vec_new: DefPath::new("std::vec::Vec::new", tcx),
vec_push: DefPath::new("std::vec::Vec::push", tcx),
vec_with_capacity: DefPath::new("std::vec::Vec::with_capacity", tcx),
vec_reserve: DefPath::new("std::vec::Vec::reserve", tcx),
}
}
}
pub struct LoopFinder<'tcx> {
pub typeck_results: &'tcx TypeckResults<'tcx>,
pub record: Vec<(Span, Vec<Span>)>,
}
pub struct PushFinder<'tcx> {
typeck_results: &'tcx TypeckResults<'tcx>,
record: Vec<Span>,
}
impl<'tcx> intravisit::Visitor<'tcx> for PushFinder<'tcx> {
fn visit_expr(&mut self, ex: &'tcx Expr<'tcx>) {
if let ExprKind::MethodCall(.., span) = ex.kind {
let def_id = self
.typeck_results
.type_dependent_def_id(ex.hir_id)
.unwrap();
let target_def_id = (&DEFPATHS.get().unwrap()).vec_push.last_def_id();
if def_id == target_def_id {
self.record.push(span);
}
}
intravisit::walk_expr(self, ex);
}
}
impl<'tcx> intravisit::Visitor<'tcx> for LoopFinder<'tcx> {
fn visit_expr(&mut self, ex: &'tcx Expr<'tcx>) {
if let ExprKind::Loop(block, ..) = ex.kind {
let mut push_finder = PushFinder {
typeck_results: self.typeck_results,
record: Vec::new(),
};
intravisit::walk_block(&mut push_finder, block);
if push_finder.record.len() == 1 {
self.record.push((ex.span, push_finder.record));
}
}
intravisit::walk_expr(self, ex);
}
}
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 _ = &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 mut loop_finder = LoopFinder {
typeck_results,
record: Vec::new(),
};
intravisit::walk_body(&mut loop_finder, body);
for (_, push_record) in loop_finder.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();
println!("{}", renderer.render(message));
}