feat(client): ecpairing accelerated precompile

## Overview

Adds an `ecpairing` accelerated precompile for the FPVM backend.

bin/client/src/l2/precompiles/bn128_pair.rs

@@ -0,0 +1,61 @@
+//! Contains the accelerated version of the `ecPairing` precompile.
+
+use alloc::{string::ToString, vec::Vec};
+use alloy_primitives::{keccak256, Address, Bytes};
+use anyhow::ensure;
+use kona_preimage::{HintWriterClient, PreimageKey, PreimageKeyType, PreimageOracleClient};
+use revm::{
+    precompile::{
+        bn128::pair::{ISTANBUL_PAIR_BASE, ISTANBUL_PAIR_PER_POINT},
+        u64_to_address, Error as PrecompileError, PrecompileWithAddress,
+    },
+    primitives::{Precompile, PrecompileOutput, PrecompileResult},
+};
+
+use crate::{HintType, HINT_WRITER, ORACLE_READER};
+
+const ECPAIRING_ADDRESS: Address = u64_to_address(8);
+const PAIR_ELEMENT_LEN: usize = 64 + 128;
+
+pub(crate) const FPVM_ECPAIRING: PrecompileWithAddress =
+    PrecompileWithAddress(ECPAIRING_ADDRESS, Precompile::Standard(fpvm_ecpairing));
+
+/// Performs an FPVM-accelerated `ecpairing` precompile call.
+fn fpvm_ecpairing(input: &Bytes, gas_limit: u64) -> PrecompileResult {
+    let gas_used =
+        (input.len() / PAIR_ELEMENT_LEN) as u64 * ISTANBUL_PAIR_PER_POINT + ISTANBUL_PAIR_BASE;
+
+    if gas_used > gas_limit {
+        return Err(PrecompileError::OutOfGas.into());
+    }
+
+    if input.len() % PAIR_ELEMENT_LEN != 0 {
+        return Err(PrecompileError::Bn128PairLength.into());
+    }
+
+    let result_data = kona_common::block_on(async move {
+        // Write the hint for the ecrecover precompile run.
+        let hint_data = &[ECPAIRING_ADDRESS.as_ref(), input.as_ref()];
+        HINT_WRITER.write(&HintType::L1Precompile.encode_with(hint_data)).await?;
+
+        // Construct the key hash for the ecrecover precompile run.
+        let raw_key_data = hint_data.iter().copied().flatten().copied().collect::<Vec<u8>>();
+        let key_hash = keccak256(&raw_key_data);
+
+        // Fetch the result of the ecrecover precompile run from the host.
+        let result_data =
+            ORACLE_READER.get(PreimageKey::new(*key_hash, PreimageKeyType::Precompile)).await?;
+
+        // Ensure we've received valid result data.
+        ensure!(!result_data.is_empty(), "Invalid result data");
+
+        // Ensure we've not received an error from the host.
+        ensure!(result_data[0] != 0, "Error executing ecrecover precompile in host");
+
+        // Return the result data.
+        Ok(result_data[1..].to_vec())
+    })
+    .map_err(|e| PrecompileError::Other(e.to_string()))?;
+
+    Ok(PrecompileOutput::new(gas_used, result_data.into()))
+}

bin/client/src/l2/precompiles/mod.rs

@@ -7,6 +7,7 @@ use revm::{
     handler::register::EvmHandler, precompile::PrecompileSpecId, ContextPrecompiles, State,
 };
 
+mod bn128_pair;
 mod ecrecover;
 
 /// The [PrecompileOverride] implementation for the FPVM-accelerated precompiles.
@@ -42,7 +43,7 @@ where
                 ContextPrecompiles::new(PrecompileSpecId::from_spec_id(spec_id)).clone();
 
             // Extend with FPVM-accelerated precompiles
-            let override_precompiles = [ecrecover::FPVM_ECRECOVER];
+            let override_precompiles = [ecrecover::FPVM_ECRECOVER, bn128_pair::FPVM_ECPAIRING];
             ctx_precompiles.extend(override_precompiles);
 
             ctx_precompiles