From d2e55fb25826a38c855b07dcf0213dec188fe076 Mon Sep 17 00:00:00 2001
From: Greg Fitzgerald <greg@solana.com>
Date: Mon, 26 Nov 2018 22:44:10 -0700
Subject: [PATCH] Hoist load_loaders()

This makes execute_transactions() stateless.
---
 src/bank.rs | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/bank.rs b/src/bank.rs
index 075e1bf413d8e0..594a12b308a3be 100644
--- a/src/bank.rs
+++ b/src/bank.rs
@@ -773,12 +773,11 @@ impl Bank {
     /// This method calls each instruction in the transaction over the set of loaded Accounts
     /// The accounts are committed back to the bank only if every instruction succeeds
     fn execute_transaction(
-        &self,
         tx: &Transaction,
+        loaders: &mut [Vec<(Pubkey, Account)>],
         tx_accounts: &mut [Account],
         tick_height: u64,
     ) -> Result<()> {
-        let mut loaders = self.load_loaders(tx)?;
         for (instruction_index, instruction) in tx.instructions.iter().enumerate() {
             let ref mut executable_accounts = &mut loaders[instruction.program_ids_index as usize];
             Self::with_subset(tx_accounts, &instruction.accounts, |program_accounts| {
@@ -902,7 +901,10 @@ impl Bank {
             .zip(txs.iter())
             .map(|(acc, tx)| match acc {
                 Err(e) => Err(e.clone()),
-                Ok(ref mut accounts) => self.execute_transaction(tx, accounts, tick_height),
+                Ok(ref mut accounts) => {
+                    let mut loaders = self.load_loaders(tx)?;
+                    Self::execute_transaction(tx, &mut loaders, accounts, tick_height)
+                }
             }).collect();
         let execution_elapsed = now.elapsed();
         let now = Instant::now();