Avoid cloning constants when compiling hints (#2208)

* Avoid cloning constants when compiling hints

By changing the compile_hint parameter type to `Arc` instead of `Rc`, we
can reuse the constants that are already included in `Program`. This
avoids cloning all the constants.

With this commit, there is a 9.8% performance increase when replaying
mainnet block 10000, compared to 2.5.0.

* Update CHANGELOG.md

---------

Co-authored-by: Gabriel Bosio <38794644+gabrielbosio@users.noreply.github.com>

Author: JulianGCalderon

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 #### Upcoming Changes
 
+* opt(breaking): Avoid cloning constants when compiling hints [#2208](https://github.com/lambdaclass/cairo-vm/pull/2208)
+
 * dev(BREAKING): Make blake2s API internal [#2265](https://github.com/lambdaclass/cairo-vm/pull/2265)
 
 * bugfix: Fix temp segment chain bug [#2195](https://github.com/lambdaclass/cairo-vm/pull/2195)

vm/src/hint_processor/builtin_hint_processor/builtin_hint_processor_definition.rs

@@ -115,7 +115,7 @@ use crate::{
         hint_processor_definition::HintReference,
     },
     serde::deserialize_program::ApTracking,
-    stdlib::{any::Any, collections::HashMap, prelude::*, rc::Rc},
+    stdlib::{any::Any, collections::HashMap, prelude::*, rc::Rc, sync::Arc},
     types::exec_scope::ExecutionScopes,
     vm::{errors::hint_errors::HintError, vm_core::VirtualMachine},
 };
@@ -133,7 +133,7 @@ pub struct HintProcessorData {
     pub ap_tracking: ApTracking,
     pub ids_data: HashMap<String, HintReference>,
     pub accessible_scopes: Vec<String>,
-    pub constants: Rc<HashMap<String, Felt252>>,
+    pub constants: Arc<HashMap<String, Felt252>>,
 }
 
 impl HintProcessorData {

vm/src/hint_processor/cairo_1_hint_processor/hint_processor.rs

@@ -9,7 +9,7 @@ use super::hint_processor_utils::*;
 use crate::any_box;
 use crate::hint_processor::cairo_1_hint_processor::dict_manager::DictSquashExecScope;
 use crate::hint_processor::hint_processor_definition::HintReference;
-use crate::stdlib::rc::Rc;
+use crate::stdlib::sync::Arc;
 use crate::stdlib::{boxed::Box, collections::HashMap, prelude::*};
 use crate::types::relocatable::{MaybeRelocatable, Relocatable};
 use crate::vm::runners::cairo_runner::ResourceTracker;
@@ -1267,7 +1267,7 @@ impl HintProcessorLogic for Cairo1HintProcessor {
         // List of accessible scopes in the hint
         _accessible_scopes: &[String],
         // Identifiers stored in the hint's program.
-        _constants: Rc<HashMap<String, Felt252>>,
+        _constants: Arc<HashMap<String, Felt252>>,
     ) -> Result<Box<dyn Any>, VirtualMachineError> {
         let data = hint_code.parse().ok().and_then(|x: usize| self.hints.get(&x).cloned())
         .ok_or_else(|| VirtualMachineError::CompileHintFail(

vm/src/hint_processor/hint_processor_definition.rs

@@ -1,4 +1,4 @@
-use crate::stdlib::{any::Any, boxed::Box, collections::HashMap, prelude::*, rc::Rc};
+use crate::stdlib::{any::Any, boxed::Box, collections::HashMap, prelude::*, sync::Arc};
 
 use crate::any_box;
 use crate::serde::deserialize_program::ApTracking;
@@ -44,7 +44,7 @@ pub trait HintProcessorLogic {
         // List of accessible scopes in the hint
         accessible_scopes: &[String],
         // Identifiers stored in the hint's program.
-        constants: Rc<HashMap<String, Felt252>>,
+        constants: Arc<HashMap<String, Felt252>>,
     ) -> Result<Box<dyn Any>, VirtualMachineError> {
         Ok(any_box!(HintProcessorData {
             code: hint_code.to_string(),

vm/src/serde/deserialize_program.rs

@@ -493,7 +493,7 @@ pub fn parse_program_json(
     };
     Ok(Program {
         shared_program_data: Arc::new(shared_program_data),
-        constants,
+        constants: Arc::new(constants),
         builtins: program_json.builtins,
     })
 }

vm/src/types/program.rs

@@ -201,7 +201,7 @@ pub type HintRange = (usize, NonZeroUsize);
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub struct Program {
     pub shared_program_data: Arc<SharedProgramData>,
-    pub constants: HashMap<String, Felt252>,
+    pub constants: Arc<HashMap<String, Felt252>>,
     pub(crate) builtins: Vec<BuiltinName>,
 }
 
@@ -235,7 +235,7 @@ impl Program {
         };
         Ok(Self {
             shared_program_data: Arc::new(shared_program_data),
-            constants,
+            constants: Arc::new(constants),
             builtins,
         })
     }
@@ -269,7 +269,7 @@ impl Program {
         };
         Ok(Self {
             shared_program_data: Arc::new(shared_program_data),
-            constants,
+            constants: Arc::new(constants),
             builtins,
         })
     }
@@ -420,7 +420,7 @@ impl Default for Program {
     fn default() -> Self {
         Self {
             shared_program_data: Arc::new(SharedProgramData::default()),
-            constants: HashMap::new(),
+            constants: Arc::new(HashMap::new()),
             builtins: Vec::new(),
         }
     }
@@ -760,7 +760,8 @@ mod tests {
             [("__main__.main.SIZEOF_LOCALS", Felt252::ZERO)]
                 .into_iter()
                 .map(|(key, value)| (key.to_string(), value))
-                .collect::<HashMap<_, _>>(),
+                .collect::<HashMap<_, _>>()
+                .into(),
         );
     }
 
@@ -1413,7 +1414,7 @@ mod tests {
         .map(|(key, value)| (key.to_string(), value))
         .collect::<HashMap<_, _>>();
 
-        assert_eq!(program.constants, constants);
+        assert_eq!(program.constants, constants.into());
     }
 
     #[test]
@@ -1439,7 +1440,7 @@ mod tests {
         };
         let program = Program {
             shared_program_data: Arc::new(shared_program_data),
-            constants: HashMap::new(),
+            constants: Arc::new(HashMap::new()),
             builtins: Vec::new(),
         };
 

vm/src/utils.rs

@@ -316,7 +316,7 @@ pub mod test_utils {
             };
             Program {
                 shared_program_data: Arc::new(shared_program_data),
-                constants: crate::stdlib::collections::HashMap::new(),
+                constants: crate::stdlib::collections::HashMap::new().into(),
                 builtins: vec![$( $builtin_name ),*],
             }
         }};
@@ -400,7 +400,7 @@ pub mod test_utils {
                     identifiers: val.identifiers,
                     reference_manager: Program::get_reference_list(&val.reference_manager),
                 }),
-                constants: val.constants,
+                constants: val.constants.into(),
                 builtins: val.builtins,
             }
         }
@@ -476,7 +476,7 @@ pub mod test_utils {
         ($vm:expr, $ids_data:expr, $hint_code:expr, $exec_scopes:expr, $constants:expr) => {{
             let mut hint_data = HintProcessorData::new_default($hint_code.to_string(), $ids_data);
             let constants: &HashMap<String, Felt252> = $constants;
-            hint_data.constants = crate::stdlib::rc::Rc::new(constants.clone());
+            hint_data.constants = constants.clone().into();
             let mut hint_processor = BuiltinHintProcessor::new_empty();
             hint_processor.execute_hint(&mut $vm, $exec_scopes, &any_box!(hint_data))
         }};
@@ -978,7 +978,7 @@ mod test {
         };
         let program = Program {
             shared_program_data: Arc::new(shared_data),
-            constants: HashMap::new(),
+            constants: HashMap::new().into(),
             builtins: Vec::new(),
         };
         assert_eq!(program, program!())
@@ -1002,7 +1002,7 @@ mod test {
         };
         let program = Program {
             shared_program_data: Arc::new(shared_data),
-            constants: HashMap::new(),
+            constants: HashMap::new().into(),
             builtins: vec![BuiltinName::range_check],
         };
 
@@ -1027,7 +1027,7 @@ mod test {
         };
         let program = Program {
             shared_program_data: Arc::new(shared_data),
-            constants: HashMap::new(),
+            constants: HashMap::new().into(),
             builtins: vec![BuiltinName::range_check],
         };
 

vm/src/vm/runners/cairo_runner.rs

@@ -9,7 +9,6 @@ use crate::{
         collections::{BTreeMap, HashMap, HashSet},
         ops::{Add, AddAssign, Mul, MulAssign, Sub, SubAssign},
         prelude::*,
-        rc::Rc,
     },
     types::{builtin_name::BuiltinName, layout::CairoLayoutParams, layout_name::LayoutName},
     vm::{
@@ -648,8 +647,6 @@ impl CairoRunner {
         references: &[HintReference],
         hint_executor: &mut dyn HintProcessor,
     ) -> Result<Vec<Box<dyn Any>>, VirtualMachineError> {
-        let constants = Rc::new(self.program.constants.clone());
-
         self.program
             .shared_program_data
             .hints_collection
@@ -662,7 +659,7 @@ impl CairoRunner {
                         &hint.flow_tracking_data.reference_ids,
                         references,
                         &hint.accessible_scopes,
-                        constants.clone(),
+                        self.program.constants.clone(),
                     )
                     .map_err(|_| VirtualMachineError::CompileHintFail(hint.code.clone().into()))
             })