From 89245adabca554747502e4294c838639468ef1f5 Mon Sep 17 00:00:00 2001
From: Vladislav Volosnikov <Volosnikov.apmath@gmail.com>
Date: Wed, 28 Aug 2024 17:01:37 +0200
Subject: [PATCH] Simplify _fetchDeployedCodeLen

---
 .../EvmInterpreterFunctions.template.yul      | 23 ++++------
 .../contracts/EvmInterpreterPreprocessed.yul  | 46 +++++++------------
 2 files changed, 24 insertions(+), 45 deletions(-)

diff --git a/system-contracts/contracts/EvmInterpreterFunctions.template.yul b/system-contracts/contracts/EvmInterpreterFunctions.template.yul
index c6f7d0b2f..387885695 100644
--- a/system-contracts/contracts/EvmInterpreterFunctions.template.yul
+++ b/system-contracts/contracts/EvmInterpreterFunctions.template.yul
@@ -264,24 +264,17 @@ function _fetchDeployedCodeWithDest(addr, _offset, _len, dest) -> codeLen {
 function _fetchDeployedCodeLen(addr) -> codeLen {
     let codeHash := _getRawCodeHash(addr)
 
-    mstore(0, codeHash)
-
-    let success := staticcall(gas(), CODE_ORACLE_SYSTEM_CONTRACT(), 0, 32, 0, 0)
-
-    switch iszero(success)
+    switch shr(248, codeHash)
     case 1 {
-        // The code oracle call can only fail in the case where the contract
-        // we are querying is the current one executing and it has not yet been
-        // deployed, i.e., if someone calls codesize (or extcodesize(address()))
-        // inside the constructor. In that case, code length is zero.
-        codeLen := 0
+        // EraVM
+        let codeLengthInWords := and(shr(224, codeHash), 0xffff)
+        codeLen := shl(5, codeLengthInWords) // codeLengthInWords * 32
     }
-    default {
-        // The first word is the true length of the bytecode
-        returndatacopy(0, 0, 32)
-        codeLen := mload(0)
+    case 2 {
+        // EVM
+        let codeLengthInBytes := and(shr(224, codeHash), 0xffff)
+        codeLen := codeLengthInBytes
     }
-
 }
 
 function getDeployedBytecode() {
diff --git a/system-contracts/contracts/EvmInterpreterPreprocessed.yul b/system-contracts/contracts/EvmInterpreterPreprocessed.yul
index 6d1fe6fe9..6caa979c2 100644
--- a/system-contracts/contracts/EvmInterpreterPreprocessed.yul
+++ b/system-contracts/contracts/EvmInterpreterPreprocessed.yul
@@ -333,24 +333,17 @@ object "EVMInterpreter" {
         function _fetchDeployedCodeLen(addr) -> codeLen {
             let codeHash := _getRawCodeHash(addr)
         
-            mstore(0, codeHash)
-        
-            let success := staticcall(gas(), CODE_ORACLE_SYSTEM_CONTRACT(), 0, 32, 0, 0)
-        
-            switch iszero(success)
+            switch shr(248, codeHash)
             case 1 {
-                // The code oracle call can only fail in the case where the contract
-                // we are querying is the current one executing and it has not yet been
-                // deployed, i.e., if someone calls codesize (or extcodesize(address()))
-                // inside the constructor. In that case, code length is zero.
-                codeLen := 0
+                // EraVM
+                let codeLengthInWords := and(shr(224, codeHash), 0xffff)
+                codeLen := shl(5, codeLengthInWords) // codeLengthInWords * 32
             }
-            default {
-                // The first word is the true length of the bytecode
-                returndatacopy(0, 0, 32)
-                codeLen := mload(0)
+            case 2 {
+                // EVM
+                let codeLengthInBytes := and(shr(224, codeHash), 0xffff)
+                codeLen := codeLengthInBytes
             }
-        
         }
         
         function getDeployedBytecode() {
@@ -3299,24 +3292,17 @@ object "EVMInterpreter" {
             function _fetchDeployedCodeLen(addr) -> codeLen {
                 let codeHash := _getRawCodeHash(addr)
             
-                mstore(0, codeHash)
-            
-                let success := staticcall(gas(), CODE_ORACLE_SYSTEM_CONTRACT(), 0, 32, 0, 0)
-            
-                switch iszero(success)
+                switch shr(248, codeHash)
                 case 1 {
-                    // The code oracle call can only fail in the case where the contract
-                    // we are querying is the current one executing and it has not yet been
-                    // deployed, i.e., if someone calls codesize (or extcodesize(address()))
-                    // inside the constructor. In that case, code length is zero.
-                    codeLen := 0
+                    // EraVM
+                    let codeLengthInWords := and(shr(224, codeHash), 0xffff)
+                    codeLen := shl(5, codeLengthInWords) // codeLengthInWords * 32
                 }
-                default {
-                    // The first word is the true length of the bytecode
-                    returndatacopy(0, 0, 32)
-                    codeLen := mload(0)
+                case 2 {
+                    // EVM
+                    let codeLengthInBytes := and(shr(224, codeHash), 0xffff)
+                    codeLen := codeLengthInBytes
                 }
-            
             }
             
             function getDeployedBytecode() {