Use constant PREVRANDAO value

matter-labs · Jan 2, 2025 · 7f6e3f1 · 7f6e3f1
1 parent 26df944
commit 7f6e3f1
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Showing 4 changed files with 22 additions and 34 deletions.
diff --git a/system-contracts/contracts/EvmEmulator.yul b/system-contracts/contracts/EvmEmulator.yul
@@ -87,7 +87,7 @@ object "EvmEmulator" {
         }
 
         function ORIGIN_CACHE_OFFSET() -> offset {
-            offset := mul(23, 32)
+            offset := mul(24, 32)
         }
 
         function GASPRICE_CACHE_OFFSET() -> offset {
@@ -106,12 +106,8 @@ object "EvmEmulator" {
             offset := add(BLOCKTIMESTAMP_CACHE_OFFSET(), 32)
         }
 
-        function PREVRANDAO_CACHE_OFFSET() -> offset {
-            offset := add(BLOCKNUMBER_CACHE_OFFSET(), 32)
-        }
-
         function GASLIMIT_CACHE_OFFSET() -> offset {
-            offset := add(PREVRANDAO_CACHE_OFFSET(), 32)
+            offset := add(BLOCKNUMBER_CACHE_OFFSET(), 32)
         }
 
         function CHAINID_CACHE_OFFSET() -> offset {
@@ -194,6 +190,10 @@ object "EvmEmulator" {
             value := 0xffffffffffffffffffffffffffffffffffffffff
         }
 
+        function PREVRANDAO_VALUE() -> value {
+            value := 2500000000000000 // This value is fixed in EraVM
+        }
+
         ////////////////////////////////////////////////////////////////
         //                  GENERAL FUNCTIONS
         ////////////////////////////////////////////////////////////////
@@ -1959,11 +1959,7 @@ object "EvmEmulator" {
                 }
                 case 0x44 { // OP_PREVRANDAO
                     evmGasLeft := chargeGas(evmGasLeft, 2)
-                    let _prevrandao := mload(PREVRANDAO_CACHE_OFFSET())
-                    if iszero(_prevrandao) {
-                        _prevrandao := cached(PREVRANDAO_CACHE_OFFSET(), prevrandao())
-                    }
-                    sp, stackHead := pushStackItem(sp, _prevrandao, stackHead)
+                    sp, stackHead := pushStackItem(sp, PREVRANDAO_VALUE(), stackHead)
                     ip := add(ip, 1)
                 }
                 case 0x45 { // OP_GASLIMIT
@@ -3014,7 +3010,7 @@ object "EvmEmulator" {
             }
 
             function ORIGIN_CACHE_OFFSET() -> offset {
-                offset := mul(23, 32)
+                offset := mul(24, 32)
             }
 
             function GASPRICE_CACHE_OFFSET() -> offset {
@@ -3033,12 +3029,8 @@ object "EvmEmulator" {
                 offset := add(BLOCKTIMESTAMP_CACHE_OFFSET(), 32)
             }
 
-            function PREVRANDAO_CACHE_OFFSET() -> offset {
-                offset := add(BLOCKNUMBER_CACHE_OFFSET(), 32)
-            }
-
             function GASLIMIT_CACHE_OFFSET() -> offset {
-                offset := add(PREVRANDAO_CACHE_OFFSET(), 32)
+                offset := add(BLOCKNUMBER_CACHE_OFFSET(), 32)
             }
 
             function CHAINID_CACHE_OFFSET() -> offset {
@@ -3121,6 +3113,10 @@ object "EvmEmulator" {
                 value := 0xffffffffffffffffffffffffffffffffffffffff
             }
 
+            function PREVRANDAO_VALUE() -> value {
+                value := 2500000000000000 // This value is fixed in EraVM
+            }
+
             ////////////////////////////////////////////////////////////////
             //                  GENERAL FUNCTIONS
             ////////////////////////////////////////////////////////////////
@@ -4874,11 +4870,7 @@ object "EvmEmulator" {
                     }
                     case 0x44 { // OP_PREVRANDAO
                         evmGasLeft := chargeGas(evmGasLeft, 2)
-                        let _prevrandao := mload(PREVRANDAO_CACHE_OFFSET())
-                        if iszero(_prevrandao) {
-                            _prevrandao := cached(PREVRANDAO_CACHE_OFFSET(), prevrandao())
-                        }
-                        sp, stackHead := pushStackItem(sp, _prevrandao, stackHead)
+                        sp, stackHead := pushStackItem(sp, PREVRANDAO_VALUE(), stackHead)
                         ip := add(ip, 1)
                     }
                     case 0x45 { // OP_GASLIMIT

diff --git a/system-contracts/contracts/SystemContext.sol b/system-contracts/contracts/SystemContext.sol
@@ -42,10 +42,10 @@ contract SystemContext is ISystemContext, ISystemContextDeprecated, SystemContra
 
     /// @notice The `block.coinbase` in the current transaction.
     /// @dev For the support of coinbase, we will use the bootloader formal address for now
-    /// @dev (!) EVM emulator doesn't expect this value to change
     address public coinbase = BOOTLOADER_FORMAL_ADDRESS;
 
     /// @notice Formal `block.difficulty` parameter.
+    /// @dev (!) EVM emulator doesn't expect this value to change
     uint256 public difficulty = 2.5e15;
 
     /// @notice The `block.basefee`.

diff --git a/system-contracts/evm-emulator/EvmEmulatorFunctions.template.yul b/system-contracts/evm-emulator/EvmEmulatorFunctions.template.yul
@@ -27,7 +27,7 @@ function MSG_VALUE_SYSTEM_CONTRACT() -> addr {
 }
 
 function ORIGIN_CACHE_OFFSET() -> offset {
-    offset := mul(23, 32)
+    offset := mul(24, 32)
 }
 
 function GASPRICE_CACHE_OFFSET() -> offset {
@@ -46,12 +46,8 @@ function BLOCKNUMBER_CACHE_OFFSET() -> offset {
     offset := add(BLOCKTIMESTAMP_CACHE_OFFSET(), 32)
 }
 
-function PREVRANDAO_CACHE_OFFSET() -> offset {
-    offset := add(BLOCKNUMBER_CACHE_OFFSET(), 32)
-}
-
 function GASLIMIT_CACHE_OFFSET() -> offset {
-    offset := add(PREVRANDAO_CACHE_OFFSET(), 32)
+    offset := add(BLOCKNUMBER_CACHE_OFFSET(), 32)
 }
 
 function CHAINID_CACHE_OFFSET() -> offset {
@@ -134,6 +130,10 @@ function ADDRESS_MASK() -> value { // mask for lower 160 bits
     value := 0xffffffffffffffffffffffffffffffffffffffff
 }
 
+function PREVRANDAO_VALUE() -> value {
+    value := 2500000000000000 // This value is fixed in EraVM
+}
+
 ////////////////////////////////////////////////////////////////
 //                  GENERAL FUNCTIONS
 ////////////////////////////////////////////////////////////////

diff --git a/system-contracts/evm-emulator/EvmEmulatorLoop.template.yul b/system-contracts/evm-emulator/EvmEmulatorLoop.template.yul
@@ -623,11 +623,7 @@ for { } true { } {
     }
     case 0x44 { // OP_PREVRANDAO
         evmGasLeft := chargeGas(evmGasLeft, 2)
-        let _prevrandao := mload(PREVRANDAO_CACHE_OFFSET())
-        if iszero(_prevrandao) {
-            _prevrandao := cached(PREVRANDAO_CACHE_OFFSET(), prevrandao())
-        }
-        sp, stackHead := pushStackItem(sp, _prevrandao, stackHead)
+        sp, stackHead := pushStackItem(sp, PREVRANDAO_VALUE(), stackHead)
         ip := add(ip, 1)
     }
     case 0x45 { // OP_GASLIMIT