From 2664a1f7ef1325a5c2eefc662925e9613e012da0 Mon Sep 17 00:00:00 2001
From: Michael Vines <mvines@gmail.com>
Date: Thu, 29 Oct 2020 14:15:00 -0700
Subject: [PATCH] Remove MessageProcessor::loaders

---
 programs/bpf_loader/src/lib.rs      |  1 -
 programs/bpf_loader/src/syscalls.rs |  2 --
 runtime/src/message_processor.rs    | 31 ++---------------------------
 3 files changed, 2 insertions(+), 32 deletions(-)

diff --git a/programs/bpf_loader/src/lib.rs b/programs/bpf_loader/src/lib.rs
index 889945d382..c3826ebba1 100644
--- a/programs/bpf_loader/src/lib.rs
+++ b/programs/bpf_loader/src/lib.rs
@@ -21,7 +21,6 @@ use solana_sdk::{
     bpf_loader, bpf_loader_deprecated,
     decode_error::DecodeError,
     entrypoint::SUCCESS,
-    feature_set::compute_budget_balancing,
     feature_set::{bpf_just_in_time_compilation, compute_budget_balancing},
     instruction::InstructionError,
     keyed_account::{is_executable, next_keyed_account, KeyedAccount},
diff --git a/programs/bpf_loader/src/syscalls.rs b/programs/bpf_loader/src/syscalls.rs
index bbae9192fe..c2b40a8106 100644
--- a/programs/bpf_loader/src/syscalls.rs
+++ b/programs/bpf_loader/src/syscalls.rs
@@ -1296,8 +1296,6 @@ fn call<'a>(
     for (program_id, process_instruction) in invoke_context.get_programs().iter() {
         message_processor.add_program(*program_id, *process_instruction);
     }
-    message_processor.add_loader(bpf_loader::id(), crate::process_instruction);
-    message_processor.add_loader(bpf_loader_deprecated::id(), crate::process_instruction);
 
     #[allow(clippy::deref_addrof)]
     match message_processor.process_cross_program_instruction(
diff --git a/runtime/src/message_processor.rs b/runtime/src/message_processor.rs
index c60226a038..cf91d5ebc4 100644
--- a/runtime/src/message_processor.rs
+++ b/runtime/src/message_processor.rs
@@ -328,8 +328,6 @@ pub struct MessageProcessor {
     #[serde(skip)]
     programs: Vec<(Pubkey, ProcessInstructionWithContext)>,
     #[serde(skip)]
-    loaders: Vec<(Pubkey, ProcessInstructionWithContext)>,
-    #[serde(skip)]
     native_loader: NativeLoader,
 }
 
@@ -338,7 +336,6 @@ impl std::fmt::Debug for MessageProcessor {
         #[derive(Debug)]
         struct MessageProcessor<'a> {
             programs: Vec<String>,
-            loaders: Vec<String>,
             native_loader: &'a NativeLoader,
         }
         // rustc doesn't compile due to bug without this work around
@@ -353,14 +350,6 @@ impl std::fmt::Debug for MessageProcessor {
                     format!("{}: {:p}", pubkey, erased_instruction)
                 })
                 .collect::<Vec<_>>(),
-            loaders: self
-                .loaders
-                .iter()
-                .map(|(pubkey, instruction)| {
-                    let erased_instruction: ErasedProcessInstructionWithContext = *instruction;
-                    format!("{}: {:p}", pubkey, erased_instruction)
-                })
-                .collect::<Vec<_>>(),
             native_loader: &self.native_loader,
         };
 
@@ -372,7 +361,6 @@ impl Default for MessageProcessor {
     fn default() -> Self {
         Self {
             programs: vec![],
-            loaders: vec![],
             native_loader: NativeLoader::default(),
         }
     }
@@ -381,7 +369,6 @@ impl Clone for MessageProcessor {
     fn clone(&self) -> Self {
         MessageProcessor {
             programs: self.programs.clone(),
-            loaders: self.loaders.clone(),
             native_loader: NativeLoader::default(),
         }
     }
@@ -414,10 +401,7 @@ impl MessageProcessor {
         program_id: Pubkey,
         process_instruction: ProcessInstructionWithContext,
     ) {
-        match self.loaders.iter_mut().find(|(key, _)| program_id == *key) {
-            Some((_, processor)) => *processor = process_instruction,
-            None => self.loaders.push((program_id, process_instruction)),
-        }
+        self.add_program(program_id, process_instruction);
     }
 
     fn get_compute_budget(feature_set: &FeatureSet) -> ComputeBudget {
@@ -462,17 +446,6 @@ impl MessageProcessor {
         if let Some(root_account) = keyed_accounts.iter().next() {
             if native_loader::check_id(&root_account.owner()?) {
                 let root_id = root_account.unsigned_key();
-                for (id, process_instruction) in &self.loaders {
-                    if id == root_id {
-                        // Call the program via a builtin loader
-                        return process_instruction(
-                            &root_id,
-                            &keyed_accounts[1..],
-                            instruction_data,
-                            invoke_context,
-                        );
-                    }
-                }
                 for (id, process_instruction) in &self.programs {
                     if id == root_id {
                         // Call the builtin program
@@ -493,7 +466,7 @@ impl MessageProcessor {
                 );
             } else {
                 let owner_id = &root_account.owner()?;
-                for (id, process_instruction) in &self.loaders {
+                for (id, process_instruction) in &self.programs {
                     if id == owner_id {
                         // Call the program via a builtin loader
                         return process_instruction(