refactor(autorouter/autorouter): Store ratlines in `BTreeSet` before ordering

This makes the purpose of the preconfiguration step clearer.

src/autorouter/autorouter.rs

@@ -154,7 +154,9 @@ impl<M: AccessMesadata> Autorouter<M> {
         M: Clone,
     {
         self.topo_autoroute_ratlines(
-            self.selected_ratlines(selection, active_layer),
+            self.selected_ratlines(selection, active_layer)
+                .into_iter()
+                .collect(),
             allowed_edges,
             active_layer,
             width,
@@ -264,7 +266,7 @@ impl<M: AccessMesadata> Autorouter<M> {
         &self,
         selection: &PinSelection,
         principal_layer: usize,
-    ) -> Vec<RatlineUid> {
+    ) -> BTreeSet<RatlineUid> {
         self.ratsnests()
             .on_principal_layer(principal_layer)
             .graph()
@@ -302,7 +304,11 @@ impl<M: AccessMesadata> Autorouter<M> {
             .collect()
     }
 
-    fn selected_planar_ratlines(&self, selection: &PinSelection, layer: usize) -> Vec<RatlineUid> {
+    fn selected_planar_ratlines(
+        &self,
+        selection: &PinSelection,
+        layer: usize,
+    ) -> BTreeSet<RatlineUid> {
         self.selected_ratlines(selection, layer)
             .into_iter()
             .filter(|ratline| {

src/autorouter/invoker.rs

@@ -192,7 +192,7 @@ impl<M: AccessMesadata + Clone> Invoker<M> {
                 // TODO: consider "presort by pairwise detours"
 
                 ExecutionStepper::TopoAutoroute(self.autorouter.topo_autoroute_ratlines(
-                    ratlines,
+                    ratlines.into_iter().collect(),
                     allowed_edges.clone(),
                     active_layer,
                     *routed_band_width,

src/autorouter/multilayer_preconfigurer.rs

@@ -2,7 +2,7 @@
 //
 // SPDX-License-Identifier: MIT
 
-use std::collections::BTreeMap;
+use std::collections::{BTreeMap, BTreeSet};
 
 use derive_getters::Getters;
 use specctra_core::mesadata::AccessMesadata;
@@ -23,7 +23,7 @@ use crate::{
 
 #[derive(Clone, Debug)]
 pub struct MultilayerAutoroutePreconfigurerInput {
-    pub ratlines: Vec<RatlineUid>,
+    pub ratlines: BTreeSet<RatlineUid>,
 }
 
 #[derive(Getters)]
@@ -50,7 +50,7 @@ impl MultilayerPreconfigurer {
 
     pub fn new_from_layer_map(
         autorouter: &Autorouter<impl AccessMesadata>,
-        ratlines: &[RatlineUid],
+        ratlines: &BTreeSet<RatlineUid>,
         layer_map: BTreeMap<RatlineUid, usize>,
     ) -> Self {
         let mut plan = AnterouterPlan {

src/autorouter/multilayer_reconfigurer.rs

@@ -2,7 +2,7 @@
 //
 // SPDX-License-Identifier: MIT
 
-use std::time::SystemTime;
+use std::{collections::BTreeSet, time::SystemTime};
 
 use specctra_core::mesadata::AccessMesadata;
 
@@ -12,13 +12,13 @@ use crate::autorouter::{
 };
 
 pub struct MultilayerReconfigurer {
-    original_ratlines: Vec<RatlineUid>,
+    original_ratlines: BTreeSet<RatlineUid>,
 }
 
 impl MultilayerReconfigurer {
     pub fn new(
         autorouter: &Autorouter<impl AccessMesadata>,
-        ratlines: Vec<RatlineUid>,
+        ratlines: BTreeSet<RatlineUid>,
         options: &MultilayerAutorouteOptions,
     ) -> Self {
         Self {

src/autorouter/planar_preconfigurer.rs

@@ -2,6 +2,8 @@
 //
 // SPDX-License-Identifier: MIT
 
+use std::collections::BTreeSet;
+
 use derive_getters::{Dissolve, Getters};
 use enum_dispatch::enum_dispatch;
 use petgraph::algo::tarjan_scc;
@@ -14,7 +16,7 @@ use crate::autorouter::{
 
 #[derive(Clone, Debug)]
 pub struct PlanarAutoroutePreconfigurerInput {
-    pub ratlines: Vec<RatlineUid>,
+    pub ratlines: BTreeSet<RatlineUid>,
 }
 
 pub struct PresortParams {

src/autorouter/planar_reconfigurer.rs

@@ -39,14 +39,14 @@ pub enum PlanarAutorouteReconfigurer {
 impl PlanarAutorouteReconfigurer {
     pub fn new(
         autorouter: &mut Autorouter<impl AccessMesadata>,
-        input_configuration: PlanarAutorouteConfiguration,
+        preconfiguration: PlanarAutorouteConfiguration,
         presorter: SccIntersectionsAndLengthRatlinePlanarAutoroutePreconfigurer,
         options: &PlanarAutorouteOptions,
     ) -> Self {
         PlanarAutorouteReconfigurer::SccPermutations(
             SccPermutationsPlanarAutorouteReconfigurer::new(
                 autorouter,
-                input_configuration,
+                preconfiguration,
                 presorter,
                 options,
             ),
@@ -65,7 +65,7 @@ pub struct SccPermutationsPlanarAutorouteReconfigurer {
 impl SccPermutationsPlanarAutorouteReconfigurer {
     pub fn new(
         _autorouter: &mut Autorouter<impl AccessMesadata>,
-        input_configuration: PlanarAutorouteConfiguration,
+        preconfiguration: PlanarAutorouteConfiguration,
         presorter: SccIntersectionsAndLengthRatlinePlanarAutoroutePreconfigurer,
         _options: &PlanarAutorouteOptions,
     ) -> Self {
@@ -76,7 +76,7 @@ impl SccPermutationsPlanarAutorouteReconfigurer {
 
         Self {
             sccs_permutations_iter: sccs.into_iter().permutations(sccs_len).skip(1),
-            initial_configuration: input_configuration,
+            initial_configuration: preconfiguration,
         }
     }
 }

src/autorouter/scc.rs

@@ -2,6 +2,8 @@
 //
 // SPDX-License-Identifier: MIT
 
+use std::collections::BTreeSet;
+
 use derive_getters::Getters;
 use petgraph::{graph::NodeIndex, prelude::StableUnGraph};
 use specctra_core::mesadata::AccessMesadata;
@@ -27,7 +29,7 @@ pub struct Scc {
 impl Scc {
     pub fn new(
         autorouter: &mut Autorouter<impl AccessMesadata>,
-        ratlines: &[RatlineUid],
+        ratlines: &BTreeSet<RatlineUid>,
         filtered_ratsnest: &StableUnGraph<RatvertexWeight, RatlineWeight, usize>,
         node_indices: Vec<NodeIndex<usize>>,
     ) -> Self {