roc-lang/roc
1
1
Fork 0
mirror of https://github.com/roc-lang/roc.git synced 2024-11-11 05:34:11 +03:00
Code Issues Packages Projects Releases Wiki Activity

Checking if a connected component has a bridge needs to look at all edges

Browse Source 
With a graph

A -> B

if we visit the order B, A to collect SCCs, we won't see that B has
pre-order edges until we look at A.
This commit is contained in:
Ayaz Hafiz 2022-12-02 08:55:26 -06:00
parent 0a807dc43e
commit 947808bbb3
No known key found for this signature in database
GPG Key ID: 0E2A37416A25EF58
1 changed files with 7 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
crates/compiler/collections/src/reference_matrix.rs
View File

@ -181,7 +181,7 @@ struct Params {
p: Vec<u32>,
s: Vec<u32>,
scc: Sccs,
scca: BitVec,
scca: Vec<u32>,
}
impl Params {
@ -202,7 +202,8 @@ impl Params {
components: 0,
not_initial: BitVec::repeat(false, length),
},
scca: BitVec::repeat(false, length),
// use u32::MAX as the sentinel empty value
scca: vec![u32::MAX; length],
}
}
}
@ -216,7 +217,7 @@ fn recurse_onto(length: usize, bitvec: &BitVec, v: usize, params: &mut Params) {
params.p.push(v as u32);
for w in bitvec[v * length..][..length].iter_ones() {
if !params.scca[w] {
if params.scca[w] == u32::MAX {
match params.preorders[w] {
Preorder::Filled(pw) => loop {
let index = *params.p.last().unwrap();
@ -236,6 +237,8 @@ fn recurse_onto(length: usize, bitvec: &BitVec, v: usize, params: &mut Params) {
Preorder::Empty => recurse_onto(length, bitvec, w, params),
Preorder::Removed => {}
}
} else {
params.scc.not_initial.set(params.scca[w] as _, true);
}
}
@ -247,7 +250,7 @@ fn recurse_onto(length: usize, bitvec: &BitVec, v: usize, params: &mut Params) {
.scc
.matrix
.set_row_col(params.scc.components, node as usize, true);
params.scca.set(node as usize, true);
params.scca[node as usize] = params.scc.components as _;
params.preorders[node as usize] = Preorder::Removed;
if node as usize == v {
break;