Add assert le find small arcs (#406)

* Add get_segment_arena_index

* Add assert_le_find_small_arcs

Author: matias-gonz

Cargo.lock

@@ -7,5 +7,6 @@ edition = "2021"
 cairo-rs = { git="https://github.com/lambdaclass/cairo-rs/", rev = "725c17e6b4c50ecf9fbb0113ecf172d858372954", package = "cairo-vm" }
 felt = { git="https://github.com/lambdaclass/cairo-rs/", rev = "725c17e6b4c50ecf9fbb0113ecf172d858372954", package = "cairo-felt" }
 cairo-lang-casm = { git = "https://github.com/starkware-libs/cairo" }
+cairo-lang-utils = "0.1.0"
 num-integer = "0.1.45"
 num-traits = "0.2.15"

crates/cairo-1-hint-processor/Cargo.toml

@@ -0,0 +1,125 @@
+#![allow(dead_code)] //TODO: remove after implementing all hints
+
+use std::collections::HashMap;
+
+use cairo_rs::{types::relocatable::Relocatable, vm::vm_core::VirtualMachine};
+use felt::Felt252;
+
+/// Stores the data of a specific dictionary.
+pub struct DictTrackerExecScope {
+    /// The data of the dictionary.
+    data: HashMap<Felt252, Felt252>,
+    /// The index of the dictionary in the dict_infos segment.
+    #[allow(dead_code)]
+    idx: usize,
+}
+
+/// Helper object to allocate, track and destruct all dictionaries in the run.
+#[derive(Default)]
+pub struct DictManagerExecScope {
+    /// Maps between a segment index and the DictTrackerExecScope associated with it.
+    trackers: HashMap<isize, DictTrackerExecScope>,
+}
+
+impl DictTrackerExecScope {
+    /// Creates a new tracker placed in index `idx` in the dict_infos segment.
+    pub fn new(idx: usize) -> Self {
+        Self {
+            data: HashMap::default(),
+            idx,
+        }
+    }
+}
+
+impl DictManagerExecScope {
+    pub const DICT_DEFAULT_VALUE: usize = 0;
+
+    /// Allocates a new segment for a new dictionary and return the start of the segment.
+    pub fn new_default_dict(&mut self, vm: &mut VirtualMachine) -> Relocatable {
+        let dict_segment = vm.add_memory_segment();
+        assert!(
+            self.trackers
+                .insert(
+                    dict_segment.segment_index,
+                    DictTrackerExecScope::new(self.trackers.len())
+                )
+                .is_none(),
+            "Segment index already in use."
+        );
+        dict_segment
+    }
+
+    /// Returns a reference for a dict tracker corresponding to a given pointer to a dict segment.
+    fn get_dict_tracker(&self, dict_end: Relocatable) -> &DictTrackerExecScope {
+        self.trackers
+            .get(&dict_end.segment_index)
+            .expect("The given value does not point to a known dictionary.")
+    }
+
+    /// Returns a mut reference for a dict tracker corresponding to a given pointer to a dict
+    /// segment.
+    fn get_dict_tracker_mut(&mut self, dict_end: Relocatable) -> &mut DictTrackerExecScope {
+        self.trackers
+            .get_mut(&dict_end.segment_index)
+            .expect("The given value does not point to a known dictionary.")
+    }
+
+    /// Returns the index of the dict tracker corresponding to a given pointer to a dict segment.
+    pub fn get_dict_infos_index(&self, dict_end: Relocatable) -> usize {
+        self.get_dict_tracker(dict_end).idx
+    }
+
+    /// Inserts a value to the dict tracker corresponding to a given pointer to a dict segment.
+    pub fn insert_to_tracker(&mut self, dict_end: Relocatable, key: Felt252, value: Felt252) {
+        self.get_dict_tracker_mut(dict_end).data.insert(key, value);
+    }
+
+    /// Gets a value from the dict tracker corresponding to a given pointer to a dict segment.
+    /// None if the key does not exist in the tracker data.
+    pub fn get_from_tracker(&self, dict_end: Relocatable, key: &Felt252) -> Option<Felt252> {
+        self.get_dict_tracker(dict_end).data.get(key).cloned()
+    }
+}
+
+/// Helper object for the management of dict_squash hints.
+#[derive(Default, Debug)]
+pub struct DictSquashExecScope {
+    /// A map from key to the list of indices accessing it, each list in reverse order.
+    pub access_indices: HashMap<Felt252, Vec<Felt252>>,
+    /// Descending list of keys.
+    pub keys: Vec<Felt252>,
+}
+
+impl DictSquashExecScope {
+    /// Returns the current key to process.
+    pub fn current_key(&self) -> Option<Felt252> {
+        self.keys.last().cloned()
+    }
+
+    /// Returns and removes the current key, and its access indices. Should be called when only the
+    /// last key access is in the corresponding indices list.
+    pub fn pop_current_key(&mut self) -> Option<Felt252> {
+        let key_accesses = self.access_indices.remove(&self.current_key().unwrap());
+        assert!(
+            key_accesses.unwrap().len() == 1,
+            "Key popped but not all accesses were processed."
+        );
+        self.keys.pop()
+    }
+
+    /// Returns a reference to the access indices list of the current key.
+    pub fn current_access_indices(&mut self) -> Option<&mut Vec<Felt252>> {
+        let current_key = self.current_key()?;
+        self.access_indices.get_mut(&current_key)
+    }
+
+    /// Returns a reference to the last index in the current access indices list.
+    pub fn current_access_index(&mut self) -> Option<&Felt252> {
+        self.current_access_indices()?.last()
+    }
+
+    /// Returns and removes the current access index.
+    pub fn pop_current_access_index(&mut self) -> Option<Felt252> {
+        self.current_access_indices()?.pop()
+    }
+}