blockifier: move logic inside felt_size_count

Author: avivg-starkware

crates/blockifier/src/execution/contract_class.rs

@@ -84,6 +84,19 @@ impl FeltSizeCount {
     pub fn n_felts(&self) -> usize {
         self.small + self.large
     }
+
+    /// Returns the total number of `u32` words required to encode all felts
+    /// according to the small/large felt encoding scheme.
+    pub(crate) fn encoded_u32_len(&self) -> usize {
+        self.large * Self::U32_WORDS_PER_LARGE_FELT + self.small * Self::U32_WORDS_PER_SMALL_FELT
+    }
+
+    /// Returns the number of BLAKE opcodes required to hash the felts.
+    /// Each BLAKE opcode processes one message block of [`U32_WORDS_PER_MESSAGE`] `u32`s
+    /// (partial messages are padded).
+    pub(crate) fn blake_opcode_count(&self) -> usize {
+        self.encoded_u32_len().div_ceil(Self::U32_WORDS_PER_MESSAGE)
+    }
 }
 
 /// Counts felts in bytecode by size (small < 2^63, large >= 2^63).

crates/blockifier/src/execution/execution_utils.rs

@@ -394,18 +394,6 @@ mod blake_estimation {
     pub const STEPS_EMPTY_INPUT: usize = 170;
 }
 
-/// Calculates the total number of u32s required to encode the given number of big and small felts.
-/// Big felts encode to 8 u32s each, small felts encode to 2 u32s each.
-fn total_u32s_from_felts(n_big_felts: usize, n_small_felts: usize) -> usize {
-    let big_u32s = n_big_felts
-        .checked_mul(FeltSizeCount::U32_WORDS_PER_LARGE_FELT)
-        .expect("Overflow computing big felts u32s");
-    let small_u32s = n_small_felts
-        .checked_mul(FeltSizeCount::U32_WORDS_PER_SMALL_FELT)
-        .expect("Overflow computing small felts u32s");
-    big_u32s.checked_add(small_u32s).expect("Overflow computing total u32s")
-}
-
 fn base_steps_for_blake_hash(n_u32s: usize) -> usize {
     let rem_u32s = n_u32s % FeltSizeCount::U32_WORDS_PER_MESSAGE;
     if rem_u32s == 0 {
@@ -434,7 +422,7 @@ fn felts_steps(n_big_felts: usize, n_small_felts: usize) -> usize {
 fn estimate_steps_of_encode_felt252_data_and_calc_blake_hash(
     felt_size_groups: &FeltSizeCount,
 ) -> usize {
-    let total_u32s = total_u32s_from_felts(felt_size_groups.large, felt_size_groups.small);
+    let total_u32s = felt_size_groups.encoded_u32_len();
     if total_u32s == 0 {
         // The empty input case is a special case.
         return blake_estimation::STEPS_EMPTY_INPUT;
@@ -446,14 +434,6 @@ fn estimate_steps_of_encode_felt252_data_and_calc_blake_hash(
     base_steps.checked_add(felt_steps).expect("Overflow computing total Blake hash steps")
 }
 
-/// Returns the number of BLAKE opcodes needed to hash the given felts.
-/// Each BLAKE opcode processes 16 u32s (partial messages are padded).
-fn count_blake_opcode(felt_size_groups: &FeltSizeCount) -> usize {
-    // Count the total number of u32s to be hashed.
-    let total_u32s = total_u32s_from_felts(felt_size_groups.large, felt_size_groups.small);
-    total_u32s.div_ceil(FeltSizeCount::U32_WORDS_PER_MESSAGE)
-}
-
 /// Estimates resource usage for `encode_felt252_data_and_calc_blake_hash` in the Starknet OS.
 ///
 /// # Encoding Details
@@ -482,7 +462,7 @@ pub fn encode_and_blake_hash_resources(
 
     EstimatedExecutionResources::V2Hash {
         resources,
-        blake_count: count_blake_opcode(felt_size_groups),
+        blake_count: felt_size_groups.blake_opcode_count(),
     }
 }
 

crates/blockifier/src/execution/execution_utils_test.rs

@@ -6,7 +6,6 @@ use starknet_types_core::felt::Felt;
 use crate::execution::contract_class::FeltSizeCount;
 use crate::execution::execution_utils::blake_estimation::STEPS_EMPTY_INPUT;
 use crate::execution::execution_utils::{
-    count_blake_opcode,
     encode_and_blake_hash_resources,
     estimate_steps_of_encode_felt252_data_and_calc_blake_hash,
 };
@@ -35,7 +34,7 @@ fn test_zero_inputs() {
     assert_eq!(steps, STEPS_EMPTY_INPUT, "Unexpected base step cost for zero inputs");
 
     // No opcodes should be emitted.
-    let opcodes = count_blake_opcode(&FeltSizeCount::default());
+    let opcodes = FeltSizeCount::default().blake_opcode_count();
     assert_eq!(opcodes, 0, "Expected zero BLAKE opcodes for zero inputs");
 
     // Should result in base cost only (no opcode cost).
@@ -47,7 +46,7 @@ fn test_zero_inputs() {
 
 // TODO(AvivG): Add tests for:
 // - `estimate_steps_of_encode_felt252_data_and_calc_blake_hash` simple cases (felts input).
-// - `count_blake_opcode` simple cases (felts input).
+// - `blake_opcode_count` simple cases (felts input).
 // - `cost_of_encode_felt252_data_and_calc_blake_hash` simple cases (felts input) (including partial
 //   remainder).
 // - `cost_of_encode_felt252_data_and_calc_blake_hash` compare against actual execution resources