Auto merge of #79012 - tgnottingham:span_data_to_lines_and_cols, r=estebank

rustc_span: add span_data_to_lines_and_cols to caching source map view
This commit is contained in:
bors 2021-01-11 21:32:50 +00:00
commit fe531d5a5f
3 changed files with 221 additions and 55 deletions

View File

@ -12,7 +12,7 @@ use rustc_hir::definitions::{DefPathHash, Definitions};
use rustc_session::Session;
use rustc_span::source_map::SourceMap;
use rustc_span::symbol::Symbol;
use rustc_span::{BytePos, CachingSourceMapView, SourceFile};
use rustc_span::{BytePos, CachingSourceMapView, SourceFile, SpanData};
use rustc_span::def_id::{CrateNum, CRATE_DEF_INDEX};
use smallvec::SmallVec;
@ -248,6 +248,13 @@ impl<'a> rustc_span::HashStableContext for StableHashingContext<'a> {
) -> Option<(Lrc<SourceFile>, usize, BytePos)> {
self.source_map().byte_pos_to_line_and_col(byte)
}
fn span_data_to_lines_and_cols(
&mut self,
span: &SpanData,
) -> Option<(Lrc<SourceFile>, usize, BytePos, usize, BytePos)> {
self.source_map().span_data_to_lines_and_cols(span)
}
}
pub fn hash_stable_trait_impls<'a>(

View File

@ -1,5 +1,5 @@
use crate::source_map::SourceMap;
use crate::{BytePos, SourceFile};
use crate::{BytePos, SourceFile, SpanData};
use rustc_data_structures::sync::Lrc;
use std::ops::Range;
@ -24,6 +24,32 @@ struct CacheEntry {
file_index: usize,
}
impl CacheEntry {
#[inline]
fn update(
&mut self,
new_file_and_idx: Option<(Lrc<SourceFile>, usize)>,
pos: BytePos,
time_stamp: usize,
) {
if let Some((file, file_idx)) = new_file_and_idx {
self.file = file;
self.file_index = file_idx;
}
let line_index = self.file.lookup_line(pos).unwrap();
let line_bounds = self.file.line_bounds(line_index);
self.line_number = line_index + 1;
self.line = line_bounds;
self.touch(time_stamp);
}
#[inline]
fn touch(&mut self, time_stamp: usize) {
self.time_stamp = time_stamp;
}
}
#[derive(Clone)]
pub struct CachingSourceMapView<'sm> {
source_map: &'sm SourceMap,
@ -57,59 +83,202 @@ impl<'sm> CachingSourceMapView<'sm> {
self.time_stamp += 1;
// Check if the position is in one of the cached lines
for cache_entry in self.line_cache.iter_mut() {
if cache_entry.line.contains(&pos) {
cache_entry.time_stamp = self.time_stamp;
let cache_idx = self.cache_entry_index(pos);
if cache_idx != -1 {
let cache_entry = &mut self.line_cache[cache_idx as usize];
cache_entry.touch(self.time_stamp);
return Some((
cache_entry.file.clone(),
cache_entry.line_number,
pos - cache_entry.line.start,
));
}
return Some((
cache_entry.file.clone(),
cache_entry.line_number,
pos - cache_entry.line.start,
));
}
// No cache hit ...
let mut oldest = 0;
for index in 1..self.line_cache.len() {
if self.line_cache[index].time_stamp < self.line_cache[oldest].time_stamp {
oldest = index;
}
}
let oldest = self.oldest_cache_entry_index();
// If the entry doesn't point to the correct file, get the new file and index.
let new_file_and_idx = if !file_contains(&self.line_cache[oldest].file, pos) {
Some(self.file_for_position(pos)?)
} else {
None
};
let cache_entry = &mut self.line_cache[oldest];
cache_entry.update(new_file_and_idx, pos, self.time_stamp);
// If the entry doesn't point to the correct file, fix it up
if !file_contains(&cache_entry.file, pos) {
let file_valid;
if self.source_map.files().len() > 0 {
let file_index = self.source_map.lookup_source_file_idx(pos);
let file = self.source_map.files()[file_index].clone();
Some((cache_entry.file.clone(), cache_entry.line_number, pos - cache_entry.line.start))
}
if file_contains(&file, pos) {
cache_entry.file = file;
cache_entry.file_index = file_index;
file_valid = true;
} else {
file_valid = false;
pub fn span_data_to_lines_and_cols(
&mut self,
span_data: &SpanData,
) -> Option<(Lrc<SourceFile>, usize, BytePos, usize, BytePos)> {
self.time_stamp += 1;
// Check if lo and hi are in the cached lines.
let lo_cache_idx = self.cache_entry_index(span_data.lo);
let hi_cache_idx = self.cache_entry_index(span_data.hi);
if lo_cache_idx != -1 && hi_cache_idx != -1 {
// Cache hit for span lo and hi. Check if they belong to the same file.
let result = {
let lo = &self.line_cache[lo_cache_idx as usize];
let hi = &self.line_cache[hi_cache_idx as usize];
if lo.file_index != hi.file_index {
return None;
}
} else {
file_valid = false;
(
lo.file.clone(),
lo.line_number,
span_data.lo - lo.line.start,
hi.line_number,
span_data.hi - hi.line.start,
)
};
self.line_cache[lo_cache_idx as usize].touch(self.time_stamp);
self.line_cache[hi_cache_idx as usize].touch(self.time_stamp);
return Some(result);
}
// No cache hit or cache hit for only one of span lo and hi.
let oldest = if lo_cache_idx != -1 || hi_cache_idx != -1 {
let avoid_idx = if lo_cache_idx != -1 { lo_cache_idx } else { hi_cache_idx };
self.oldest_cache_entry_index_avoid(avoid_idx as usize)
} else {
self.oldest_cache_entry_index()
};
// If the entry doesn't point to the correct file, get the new file and index.
// Return early if the file containing beginning of span doesn't contain end of span.
let new_file_and_idx = if !file_contains(&self.line_cache[oldest].file, span_data.lo) {
let new_file_and_idx = self.file_for_position(span_data.lo)?;
if !file_contains(&new_file_and_idx.0, span_data.hi) {
return None;
}
if !file_valid {
Some(new_file_and_idx)
} else {
let file = &self.line_cache[oldest].file;
if !file_contains(&file, span_data.hi) {
return None;
}
None
};
// Update the cache entries.
let (lo_idx, hi_idx) = match (lo_cache_idx, hi_cache_idx) {
// Oldest cache entry is for span_data.lo line.
(-1, -1) => {
let lo = &mut self.line_cache[oldest];
lo.update(new_file_and_idx, span_data.lo, self.time_stamp);
if !lo.line.contains(&span_data.hi) {
let new_file_and_idx = Some((lo.file.clone(), lo.file_index));
let next_oldest = self.oldest_cache_entry_index_avoid(oldest);
let hi = &mut self.line_cache[next_oldest];
hi.update(new_file_and_idx, span_data.hi, self.time_stamp);
(oldest, next_oldest)
} else {
(oldest, oldest)
}
}
// Oldest cache entry is for span_data.lo line.
(-1, _) => {
let lo = &mut self.line_cache[oldest];
lo.update(new_file_and_idx, span_data.lo, self.time_stamp);
let hi = &mut self.line_cache[hi_cache_idx as usize];
hi.touch(self.time_stamp);
(oldest, hi_cache_idx as usize)
}
// Oldest cache entry is for span_data.hi line.
(_, -1) => {
let hi = &mut self.line_cache[oldest];
hi.update(new_file_and_idx, span_data.hi, self.time_stamp);
let lo = &mut self.line_cache[lo_cache_idx as usize];
lo.touch(self.time_stamp);
(lo_cache_idx as usize, oldest)
}
_ => {
panic!();
}
};
let lo = &self.line_cache[lo_idx];
let hi = &self.line_cache[hi_idx];
// Span lo and hi may equal line end when last line doesn't
// end in newline, hence the inclusive upper bounds below.
debug_assert!(span_data.lo >= lo.line.start);
debug_assert!(span_data.lo <= lo.line.end);
debug_assert!(span_data.hi >= hi.line.start);
debug_assert!(span_data.hi <= hi.line.end);
debug_assert!(lo.file.contains(span_data.lo));
debug_assert!(lo.file.contains(span_data.hi));
debug_assert_eq!(lo.file_index, hi.file_index);
Some((
lo.file.clone(),
lo.line_number,
span_data.lo - lo.line.start,
hi.line_number,
span_data.hi - hi.line.start,
))
}
fn cache_entry_index(&self, pos: BytePos) -> isize {
for (idx, cache_entry) in self.line_cache.iter().enumerate() {
if cache_entry.line.contains(&pos) {
return idx as isize;
}
}
let line_index = cache_entry.file.lookup_line(pos).unwrap();
let line_bounds = cache_entry.file.line_bounds(line_index);
-1
}
cache_entry.line_number = line_index + 1;
cache_entry.line = line_bounds;
cache_entry.time_stamp = self.time_stamp;
fn oldest_cache_entry_index(&self) -> usize {
let mut oldest = 0;
Some((cache_entry.file.clone(), cache_entry.line_number, pos - cache_entry.line.start))
for idx in 1..self.line_cache.len() {
if self.line_cache[idx].time_stamp < self.line_cache[oldest].time_stamp {
oldest = idx;
}
}
oldest
}
fn oldest_cache_entry_index_avoid(&self, avoid_idx: usize) -> usize {
let mut oldest = if avoid_idx != 0 { 0 } else { 1 };
for idx in 0..self.line_cache.len() {
if idx != avoid_idx
&& self.line_cache[idx].time_stamp < self.line_cache[oldest].time_stamp
{
oldest = idx;
}
}
oldest
}
fn file_for_position(&self, pos: BytePos) -> Option<(Lrc<SourceFile>, usize)> {
if !self.source_map.files().is_empty() {
let file_idx = self.source_map.lookup_source_file_idx(pos);
let file = &self.source_map.files()[file_idx];
if file_contains(file, pos) {
return Some((file.clone(), file_idx));
}
}
None
}
}

View File

@ -1871,6 +1871,10 @@ pub trait HashStableContext {
&mut self,
byte: BytePos,
) -> Option<(Lrc<SourceFile>, usize, BytePos)>;
fn span_data_to_lines_and_cols(
&mut self,
span: &SpanData,
) -> Option<(Lrc<SourceFile>, usize, BytePos, usize, BytePos)>;
}
impl<CTX> HashStable<CTX> for Span
@ -1904,22 +1908,8 @@ where
// position that belongs to it, as opposed to hashing the first
// position past it.
let span = self.data();
let (file_lo, line_lo, col_lo) = match ctx.byte_pos_to_line_and_col(span.lo) {
Some(pos) => pos,
None => {
Hash::hash(&TAG_INVALID_SPAN, hasher);
span.ctxt.hash_stable(ctx, hasher);
return;
}
};
if !file_lo.contains(span.hi) {
Hash::hash(&TAG_INVALID_SPAN, hasher);
span.ctxt.hash_stable(ctx, hasher);
return;
}
let (_, line_hi, col_hi) = match ctx.byte_pos_to_line_and_col(span.hi) {
let (file, line_lo, col_lo, line_hi, col_hi) = match ctx.span_data_to_lines_and_cols(&span)
{
Some(pos) => pos,
None => {
Hash::hash(&TAG_INVALID_SPAN, hasher);
@ -1931,7 +1921,7 @@ where
Hash::hash(&TAG_VALID_SPAN, hasher);
// We truncate the stable ID hash and line and column numbers. The chances
// of causing a collision this way should be minimal.
Hash::hash(&(file_lo.name_hash as u64), hasher);
Hash::hash(&(file.name_hash as u64), hasher);
// Hash both the length and the end location (line/column) of a span. If we
// hash only the length, for example, then two otherwise equal spans with