Implement CODESIZE

Signed-off-by: xermicus <cyrill@parity.io>

crates/integration/src/cases.rs

@@ -126,6 +126,8 @@ sol!(
 sol!(
     contract ExtCode {
         function ExtCodeSize(address who) public view returns (uint ret);
+
+        function CodeSize() public pure returns (uint ret);
     }
 );
 
@@ -461,6 +463,18 @@ impl Contract {
         }
     }
 
+    pub fn code_size() -> Self {
+        let code = include_str!("../contracts/ExtCode.sol");
+        let name = "ExtCode";
+
+        Self {
+            name,
+            evm_runtime: crate::compile_evm_bin_runtime(name, code),
+            pvm_runtime: crate::compile_blob(name, code),
+            calldata: ExtCode::CodeSizeCall::new(()).abi_encode(),
+        }
+    }
+
     pub fn memcpy(payload: Vec<u8>) -> Self {
         let code = include_str!("../contracts/MCopy.sol");
         let name = "MCopy";

crates/integration/src/mock_runtime.rs

@@ -884,20 +884,26 @@ fn link_host_functions(engine: &Engine) -> Linker<Transaction> {
             |caller: Caller<Transaction>, address_ptr: u32| {
                 let (caller, transaction) = caller.split();
 
-                let bytes = caller.read_memory_into_vec(address_ptr, 32)?;
-                let word = U256::from_le_slice(&bytes);
-                let address = Address::from_word(word.into());
+                let address = if address_ptr == u32::MAX {
+                    transaction.top_frame().callee
+                } else {
+                    let bytes = caller.read_memory_into_vec(address_ptr, 32)?;
+                    let word = U256::from_le_slice(&bytes);
+                    Address::from_word(word.into())
+                };
 
-                log::info!("{}", address);
-
-                Ok(transaction
+                let code_size = transaction
                     .state
                     .accounts
                     .get(&address)
                     .and_then(|account| account.contract)
                     .and_then(|blob_hash| transaction.state.blobs.get(&blob_hash))
                     .map(|code| code.len())
-                    .unwrap_or_default() as u32)
+                    .unwrap_or_default() as u32;
+
+                log::info!("code size of {address} = {code_size}");
+
+                Ok(code_size)
             },
         )
         .unwrap();

crates/integration/src/tests.rs

@@ -525,6 +525,15 @@ fn ext_code_size() {
     assert_eq!(received, expected);
 }
 
+#[test]
+fn code_size() {
+    let contract = Contract::code_size();
+    let (_, output) = assert_success(&contract, false);
+    let expected = U256::from(contract.pvm_runtime.len());
+    let received = U256::from_be_slice(&output.data);
+    assert_eq!(expected, received);
+}
+
 #[test]
 fn value_transfer() {
     // Succeeds in remix (shanghai) but traps the interpreter