rewrote point_evaluation_run()

crates/precompile/src/point_evaluation.rs

@@ -1,8 +1,7 @@
 use core::str::FromStr;
 
 use alloc::vec::Vec;
-use num::{BigUint, FromPrimitive};
-use revm_primitives::{PrecompileResult, StandardPrecompileFn, uint};
+use revm_primitives::{PrecompileResult, StandardPrecompileFn, uint, U256};
 use sha2::{Digest, Sha256};
 
 use crate::{Precompile, PrecompileAddress};
@@ -12,13 +11,13 @@ pub const POINT_EVALUATION_PRECOMPILE: PrecompileAddress = PrecompileAddress(
     Precompile::Standard(point_evaluation_run as StandardPrecompileFn),
 );
 
-const FIELD_ELEMENTS_PER_BLOB: u32 = 4096;
-// Modulus is 381 bits which is greater than 256 bits so need to find better type
+// `FIELD_ELEMENTS_PER_BLOB = 4096`
+// TODO: make FIELD_ELEMENTS_PER_BLOB and BLS_MODULUS a constant slice so we can easily append them
+const FIELD_ELEMENTS_PER_BLOB: [u8;4] = [0,0,16,0];
 // const BLS_MODULUS: uint<> =
 //     "52435875175126190479447740508185965837690552500527637822603658699938581184513";
-const BLS_MODULUS: &str =
-    "52435875175126190479447740508185965837690552500527637822603658699938581184513";
-const BLOB_COMMITMENT_VERSION_KZG: u8 = 0x01;
+const BLS_MODULUS: [u8;32] = [115, 237, 167, 83, 41, 157, 125, 72, 51, 57, 216, 8, 9, 161, 216, 5, 83, 189, 164, 2, 255, 254, 91, 254, 255, 255, 255, 255, 0, 0, 0, 1];
+const BLOB_COMMITMENT_VERSION_KZG: u8 = 1;
 
 pub fn point_evaluation_run(input: &[u8], gas_limit: u64) -> PrecompileResult {
     // The data is encoded as follows: versioned_hash | z | y | commitment | proof | with z and y being padded 32 byte big endian values
@@ -35,21 +34,10 @@ pub fn point_evaluation_run(input: &[u8], gas_limit: u64) -> PrecompileResult {
     // Verify KZG proof with z and y in big endian format
     assert!(_verify_kzg_proof(commitment, z, y, proof));
 
-    // Convert FIELD_ELEMENTS_PER_BLOB to BigUint
-    let field_elements_big_uint = BigUint::from_u32(FIELD_ELEMENTS_PER_BLOB).unwrap();
-    let mut field_elements_bytes = vec![0; 32];
-    let bytes_be = field_elements_big_uint.to_bytes_be();
-    field_elements_bytes[32 - bytes_be.len()..].copy_from_slice(&bytes_be);
+    let mut result = Vec::from(FIELD_ELEMENTS_PER_BLOB); // The first bytes of the result are the FIELD_ELEMENTS_PER_BLOB
+    let bls_modulus_bytes = Vec::from(BLS_MODULUS);
+    result.extend(bls_modulus_bytes); // Concatenate the BLS_MODULUS to the result
 
-    // Convert BLS_MODULUS to BigUint
-    let bls_modulus_big_uint = BigUint::from_str(BLS_MODULUS).expect("Failed to parse BLS_MODULUS");
-    let mut bls_modulus_bytes = vec![0; 32];
-    let bytes_be = bls_modulus_big_uint.to_bytes_be();
-    bls_modulus_bytes[32 - bytes_be.len()..].copy_from_slice(&bytes_be);
-
-    // Concatenate both byte arrays
-    let mut result = field_elements_bytes;
-    result.extend(bls_modulus_bytes);
     Ok((gas_limit, result))
 }