#![deny(rustc::untranslatable_diagnostic)]
#![deny(rustc::diagnostic_outside_of_impl)]
use rustc_data_structures::fx::FxIndexSet;
use rustc_index::bit_set::SparseBitMatrix;
use rustc_index::interval::IntervalSet;
use rustc_index::interval::SparseIntervalMatrix;
use rustc_index::Idx;
use rustc_index::IndexVec;
use rustc_middle::mir::{BasicBlock, Body, Location};
use rustc_middle::ty::{self, RegionVid};
use std::fmt::Debug;
use std::rc::Rc;
pub(crate) struct RegionValueElements {
statements_before_block: IndexVec<BasicBlock, usize>,
basic_blocks: IndexVec<PointIndex, BasicBlock>,
num_points: usize,
}
impl RegionValueElements {
pub(crate) fn new(body: &Body<'_>) -> Self {
let mut num_points = 0;
let statements_before_block: IndexVec<BasicBlock, usize> = body
.basic_blocks
.iter()
.map(|block_data| {
let v = num_points;
num_points += block_data.statements.len() + 1;
v
})
.collect();
debug!("RegionValueElements: statements_before_block={:#?}", statements_before_block);
debug!("RegionValueElements: num_points={:#?}", num_points);
let mut basic_blocks = IndexVec::with_capacity(num_points);
for (bb, bb_data) in body.basic_blocks.iter_enumerated() {
basic_blocks.extend((0..=bb_data.statements.len()).map(|_| bb));
}
Self { statements_before_block, basic_blocks, num_points }
}
pub(crate) fn num_points(&self) -> usize {
self.num_points
}
pub(crate) fn point_from_location(&self, location: Location) -> PointIndex {
let Location { block, statement_index } = location;
let start_index = self.statements_before_block[block];
PointIndex::new(start_index + statement_index)
}
pub(crate) fn entry_point(&self, block: BasicBlock) -> PointIndex {
let start_index = self.statements_before_block[block];
PointIndex::new(start_index)
}
pub(crate) fn to_block_start(&self, index: PointIndex) -> PointIndex {
PointIndex::new(self.statements_before_block[self.basic_blocks[index]])
}
pub(crate) fn to_location(&self, index: PointIndex) -> Location {
assert!(index.index() < self.num_points);
let block = self.basic_blocks[index];
let start_index = self.statements_before_block[block];
let statement_index = index.index() - start_index;
Location { block, statement_index }
}
pub(crate) fn point_in_range(&self, index: PointIndex) -> bool {
index.index() < self.num_points
}
}
rustc_index::newtype_index! {
#[debug_format = "PointIndex({})"]
pub struct PointIndex {}
}
rustc_index::newtype_index! {
#[debug_format = "PlaceholderIndex({})"]
pub struct PlaceholderIndex {}
}
#[derive(Debug, Clone)]
pub(crate) enum RegionElement {
Location(Location),
RootUniversalRegion(RegionVid),
PlaceholderRegion(ty::PlaceholderRegion),
}
pub(crate) struct LivenessValues<N: Idx> {
elements: Rc<RegionValueElements>,
points: SparseIntervalMatrix<N, PointIndex>,
}
impl<N: Idx> LivenessValues<N> {
pub(crate) fn new(elements: Rc<RegionValueElements>) -> Self {
Self { points: SparseIntervalMatrix::new(elements.num_points), elements }
}
pub(crate) fn rows(&self) -> impl Iterator<Item = N> {
self.points.rows()
}
pub(crate) fn add_element(&mut self, row: N, location: Location) -> bool {
debug!("LivenessValues::add(r={:?}, location={:?})", row, location);
let index = self.elements.point_from_location(location);
self.points.insert(row, index)
}
pub(crate) fn add_elements(&mut self, row: N, locations: &IntervalSet<PointIndex>) -> bool {
debug!("LivenessValues::add_elements(row={:?}, locations={:?})", row, locations);
self.points.union_row(row, locations)
}
pub(crate) fn add_all_points(&mut self, row: N) {
self.points.insert_all_into_row(row);
}
pub(crate) fn contains(&self, row: N, location: Location) -> bool {
let index = self.elements.point_from_location(location);
self.points.row(row).is_some_and(|r| r.contains(index))
}
pub(crate) fn get_elements(&self, row: N) -> impl Iterator<Item = Location> + '_ {
self.points
.row(row)
.into_iter()
.flat_map(|set| set.iter())
.take_while(move |&p| self.elements.point_in_range(p))
.map(move |p| self.elements.to_location(p))
}
pub(crate) fn region_value_str(&self, r: N) -> String {
region_value_str(self.get_elements(r).map(RegionElement::Location))
}
}
#[derive(Debug, Default)]
pub(crate) struct PlaceholderIndices {
indices: FxIndexSet<ty::PlaceholderRegion>,
}
impl PlaceholderIndices {
pub(crate) fn insert(&mut self, placeholder: ty::PlaceholderRegion) -> PlaceholderIndex {
let (index, _) = self.indices.insert_full(placeholder);
index.into()
}
pub(crate) fn lookup_index(&self, placeholder: ty::PlaceholderRegion) -> PlaceholderIndex {
self.indices.get_index_of(&placeholder).unwrap().into()
}
pub(crate) fn lookup_placeholder(
&self,
placeholder: PlaceholderIndex,
) -> ty::PlaceholderRegion {
self.indices[placeholder.index()]
}
pub(crate) fn len(&self) -> usize {
self.indices.len()
}
}
#[derive(Clone)]
pub(crate) struct RegionValues<N: Idx> {
elements: Rc<RegionValueElements>,
placeholder_indices: Rc<PlaceholderIndices>,
points: SparseIntervalMatrix<N, PointIndex>,
free_regions: SparseBitMatrix<N, RegionVid>,
placeholders: SparseBitMatrix<N, PlaceholderIndex>,
}
impl<N: Idx> RegionValues<N> {
pub(crate) fn new(
elements: &Rc<RegionValueElements>,
num_universal_regions: usize,
placeholder_indices: &Rc<PlaceholderIndices>,
) -> Self {
let num_placeholders = placeholder_indices.len();
Self {
elements: elements.clone(),
points: SparseIntervalMatrix::new(elements.num_points),
placeholder_indices: placeholder_indices.clone(),
free_regions: SparseBitMatrix::new(num_universal_regions),
placeholders: SparseBitMatrix::new(num_placeholders),
}
}
pub(crate) fn add_element(&mut self, r: N, elem: impl ToElementIndex) -> bool {
debug!("add(r={:?}, elem={:?})", r, elem);
elem.add_to_row(self, r)
}
pub(crate) fn add_all_points(&mut self, r: N) {
self.points.insert_all_into_row(r);
}
pub(crate) fn add_region(&mut self, r_to: N, r_from: N) -> bool {
self.points.union_rows(r_from, r_to)
| self.free_regions.union_rows(r_from, r_to)
| self.placeholders.union_rows(r_from, r_to)
}
pub(crate) fn contains(&self, r: N, elem: impl ToElementIndex) -> bool {
elem.contained_in_row(self, r)
}
pub(crate) fn first_non_contained_inclusive(
&self,
r: N,
block: BasicBlock,
start: usize,
end: usize,
) -> Option<usize> {
let row = self.points.row(r)?;
let block = self.elements.entry_point(block);
let start = block.plus(start);
let end = block.plus(end);
let first_unset = row.first_unset_in(start..=end)?;
Some(first_unset.index() - block.index())
}
pub(crate) fn merge_liveness<M: Idx>(&mut self, to: N, from: M, values: &LivenessValues<M>) {
if let Some(set) = values.points.row(from) {
self.points.union_row(to, set);
}
}
pub(crate) fn contains_points(&self, sup_region: N, sub_region: N) -> bool {
if let Some(sub_row) = self.points.row(sub_region) {
if let Some(sup_row) = self.points.row(sup_region) {
sup_row.superset(sub_row)
} else {
sub_row.is_empty()
}
} else {
true
}
}
pub(crate) fn locations_outlived_by<'a>(&'a self, r: N) -> impl Iterator<Item = Location> + 'a {
self.points.row(r).into_iter().flat_map(move |set| {
set.iter()
.take_while(move |&p| self.elements.point_in_range(p))
.map(move |p| self.elements.to_location(p))
})
}
pub(crate) fn universal_regions_outlived_by<'a>(
&'a self,
r: N,
) -> impl Iterator<Item = RegionVid> + 'a {
self.free_regions.row(r).into_iter().flat_map(|set| set.iter())
}
pub(crate) fn placeholders_contained_in<'a>(
&'a self,
r: N,
) -> impl Iterator<Item = ty::PlaceholderRegion> + 'a {
self.placeholders
.row(r)
.into_iter()
.flat_map(|set| set.iter())
.map(move |p| self.placeholder_indices.lookup_placeholder(p))
}
pub(crate) fn elements_contained_in<'a>(
&'a self,
r: N,
) -> impl Iterator<Item = RegionElement> + 'a {
let points_iter = self.locations_outlived_by(r).map(RegionElement::Location);
let free_regions_iter =
self.universal_regions_outlived_by(r).map(RegionElement::RootUniversalRegion);
let placeholder_universes_iter =
self.placeholders_contained_in(r).map(RegionElement::PlaceholderRegion);
points_iter.chain(free_regions_iter).chain(placeholder_universes_iter)
}
pub(crate) fn region_value_str(&self, r: N) -> String {
region_value_str(self.elements_contained_in(r))
}
}
pub(crate) trait ToElementIndex: Debug + Copy {
fn add_to_row<N: Idx>(self, values: &mut RegionValues<N>, row: N) -> bool;
fn contained_in_row<N: Idx>(self, values: &RegionValues<N>, row: N) -> bool;
}
impl ToElementIndex for Location {
fn add_to_row<N: Idx>(self, values: &mut RegionValues<N>, row: N) -> bool {
let index = values.elements.point_from_location(self);
values.points.insert(row, index)
}
fn contained_in_row<N: Idx>(self, values: &RegionValues<N>, row: N) -> bool {
let index = values.elements.point_from_location(self);
values.points.contains(row, index)
}
}
impl ToElementIndex for RegionVid {
fn add_to_row<N: Idx>(self, values: &mut RegionValues<N>, row: N) -> bool {
values.free_regions.insert(row, self)
}
fn contained_in_row<N: Idx>(self, values: &RegionValues<N>, row: N) -> bool {
values.free_regions.contains(row, self)
}
}
impl ToElementIndex for ty::PlaceholderRegion {
fn add_to_row<N: Idx>(self, values: &mut RegionValues<N>, row: N) -> bool {
let index = values.placeholder_indices.lookup_index(self);
values.placeholders.insert(row, index)
}
fn contained_in_row<N: Idx>(self, values: &RegionValues<N>, row: N) -> bool {
let index = values.placeholder_indices.lookup_index(self);
values.placeholders.contains(row, index)
}
}
pub(crate) fn location_set_str(
elements: &RegionValueElements,
points: impl IntoIterator<Item = PointIndex>,
) -> String {
region_value_str(
points
.into_iter()
.take_while(|&p| elements.point_in_range(p))
.map(|p| elements.to_location(p))
.map(RegionElement::Location),
)
}
fn region_value_str(elements: impl IntoIterator<Item = RegionElement>) -> String {
let mut result = String::new();
result.push('{');
let mut open_location: Option<(Location, Location)> = None;
let mut sep = "";
let mut push_sep = |s: &mut String| {
s.push_str(sep);
sep = ", ";
};
for element in elements {
match element {
RegionElement::Location(l) => {
if let Some((location1, location2)) = open_location {
if location2.block == l.block
&& location2.statement_index == l.statement_index - 1
{
open_location = Some((location1, l));
continue;
}
push_sep(&mut result);
push_location_range(&mut result, location1, location2);
}
open_location = Some((l, l));
}
RegionElement::RootUniversalRegion(fr) => {
if let Some((location1, location2)) = open_location {
push_sep(&mut result);
push_location_range(&mut result, location1, location2);
open_location = None;
}
push_sep(&mut result);
result.push_str(&format!("{fr:?}"));
}
RegionElement::PlaceholderRegion(placeholder) => {
if let Some((location1, location2)) = open_location {
push_sep(&mut result);
push_location_range(&mut result, location1, location2);
open_location = None;
}
push_sep(&mut result);
result.push_str(&format!("{placeholder:?}"));
}
}
}
if let Some((location1, location2)) = open_location {
push_sep(&mut result);
push_location_range(&mut result, location1, location2);
}
result.push('}');
return result;
fn push_location_range(str: &mut String, location1: Location, location2: Location) {
if location1 == location2 {
str.push_str(&format!("{location1:?}"));
} else {
assert_eq!(location1.block, location2.block);
str.push_str(&format!(
"{:?}[{}..={}]",
location1.block, location1.statement_index, location2.statement_index
));
}
}
}