From eebcd0f35badb06ad7329563a8265d9aaeee92b1 Mon Sep 17 00:00:00 2001
From: Tomusdrw <tomusdrw@gmail.com>
Date: Thu, 14 Jan 2016 12:33:49 +0100
Subject: [PATCH] Fixing memory cost calculation

---
 src/evm/interpreter.rs | 30 ++++++++++++++++--------------
 src/executive.rs       |  2 +-
 src/tests/executive.rs | 10 +++++-----
 3 files changed, 22 insertions(+), 20 deletions(-)

diff --git a/src/evm/interpreter.rs b/src/evm/interpreter.rs
index e9ac7ebca..1bbf73d0a 100644
--- a/src/evm/interpreter.rs
+++ b/src/evm/interpreter.rs
@@ -235,11 +235,11 @@ impl evm::Evm for Interpreter {
 impl Interpreter {
 
 	fn get_gas_cost_and_expand_mem(&self,
-									ext: &evm::Ext,
-									instruction: Instruction,
-									mem: &mut Memory,
-									stack: &Stack<U256>
-									) -> evm::Result {
+								   ext: &evm::Ext,
+								   instruction: Instruction,
+								   mem: &mut Memory,
+								   stack: &Stack<U256>
+								  ) -> evm::Result {
 		let schedule = ext.schedule();
 		let info = instructions::get_info(instruction);
 
@@ -262,8 +262,10 @@ impl Interpreter {
 		let cost = match instruction {
 			instructions::SSTORE => {
 				let address = H256::from(stack.peek(0));
+				let newval = stack.peek(1);
 				let val = U256::from(ext.sload(&address).as_slice());
-				let gas = if self.is_zero(&val) && !self.is_zero(stack.peek(1)) {
+
+				let gas = if self.is_zero(&val) && !self.is_zero(newval) {
 					schedule.sstore_set_gas
 				} else {
 					schedule.sstore_reset_gas
@@ -310,7 +312,7 @@ impl Interpreter {
 				InstructionCost::GasMem(gas, self.mem_needed(stack.peek(0), stack.peek(1)))
 			},
 			instructions::CALL | instructions::CALLCODE => {
-				let gas = add_u256_usize(stack.peek(0), schedule.call_gas + schedule.call_value_transfer_gas);
+				let gas = add_u256_usize(stack.peek(0), schedule.call_gas);
 				let mem = cmp::max(
 					self.mem_needed(stack.peek(5), stack.peek(6)),
 					self.mem_needed(stack.peek(3), stack.peek(4))
@@ -344,14 +346,16 @@ impl Interpreter {
 				Ok(gas)
 			},
 			InstructionCost::GasMem(gas, mem_size) => {
-				mem.expand(mem_size);
 				let mem_gas = self.mem_gas_cost(schedule, mem.size(), &mem_size);
+				// Expand after calculating the cost
+				mem.expand(mem_size);
 				Ok(gas + mem_gas)
 			},
 			InstructionCost::GasMemCopy(gas, mem_size, copy) => {
-				mem.expand(mem_size);
 				let mem_gas = self.mem_gas_cost(schedule, mem.size(), &mem_size);
 				let copy_gas = U256::from(schedule.copy_gas) * (add_u256_usize(&copy, 31) / U256::from(32));
+				// Expand after calculating the cost
+				mem.expand(mem_size);
 				Ok(gas + copy_gas + mem_gas)
 			}
 		}
@@ -482,13 +486,11 @@ impl Interpreter {
 			},
 			instructions::LOG0...instructions::LOG4 => {
 				let no_of_topics = instructions::get_log_topics(instruction);
-				let topics_data = stack.pop_n(no_of_topics + 2);
 
-				let offset = topics_data[0];
-				let size = topics_data[1];
-				let topics = topics_data
+				let offset = stack.pop_back();
+				let size = stack.pop_back();
+				let topics = stack.pop_n(no_of_topics)
 					.iter()
-					.skip(2)
 					.map(H256::from)
 					.collect();
 				ext.log(topics, mem.read_slice(offset, size));
diff --git a/src/executive.rs b/src/executive.rs
index 5d0e3789a..370eb7c0b 100644
--- a/src/executive.rs
+++ b/src/executive.rs
@@ -684,7 +684,7 @@ mod tests {
 		// 60 00 - push 0
 		// f3 - return
 
-		let code = "7c601080600c6000396000f3006000355415600957005b60203560003555600052601d60036017f0600055".from_hex().unwrap();
+		let code = "7c601080600c6000396000f3006000355415600957005b60203560003555600052601d60036017f0".from_hex().unwrap();
 
 		let sender = Address::from_str("cd1722f3947def4cf144679da39c4c32bdc35681").unwrap();
 		let address = contract_address(&sender, &U256::zero());
diff --git a/src/tests/executive.rs b/src/tests/executive.rs
index 0a71aa3e4..d49ac5f8b 100644
--- a/src/tests/executive.rs
+++ b/src/tests/executive.rs
@@ -9,14 +9,14 @@ use ethereum;
 
 struct TestEngine {
 	spec: Spec,
-	stack_limit: usize
+	max_depth: usize
 }
 
 impl TestEngine {
-	fn new(stack_limit: usize) -> TestEngine {
+	fn new(max_depth: usize) -> TestEngine {
 		TestEngine {
 			spec: ethereum::new_frontier_test(),
-			stack_limit: stack_limit 
+			max_depth: max_depth 
 		}
 	}
 }
@@ -26,7 +26,7 @@ impl Engine for TestEngine {
 	fn spec(&self) -> &Spec { &self.spec }
 	fn schedule(&self, _env_info: &EnvInfo) -> Schedule { 
 		let mut schedule = Schedule::new_frontier();
-		schedule.stack_limit = self.stack_limit; 
+		schedule.max_depth = self.max_depth; 
 		schedule
 	}
 }
@@ -87,7 +87,7 @@ impl<'a> Ext for TestExt<'a> {
 				});
 				Ok((gas_left, Some(address)))
 			},
-			// creation failed only due to reaching stack_limit
+			// creation failed only due to reaching max_depth
 			Ok((gas_left, None)) if ext.state.balance(&ext.params.address) >= *value => {
 				let address = contract_address(&ext.params.address, &ext.state.nonce(&ext.params.address));
 				self.callcreates.push(CallCreate {