Implement EIP-5920

Author: gurukamath

src/ethereum/osaka/vm/instructions/__init__.py

@@ -252,6 +252,7 @@ class Ops(enum.Enum):
     EXTDELEGATECALL = 0xF9
     STATICCALL = 0xFA
     EXTSTATICCALL = 0xFB
+    PAY = 0xFC
     REVERT = 0xFD
     INVALID = 0xFE
     SELFDESTRUCT = 0xFF
@@ -427,6 +428,7 @@ class Ops(enum.Enum):
     Ops.EXTCALL: system_instructions.ext_call,
     Ops.EXTDELEGATECALL: system_instructions.ext_delegatecall,
     Ops.EXTSTATICCALL: system_instructions.ext_staticcall,
+    Ops.PAY: system_instructions.pay,
 }
 
 
@@ -659,6 +661,7 @@ class Ops(enum.Enum):
     Ops.EXTCALL: OpcodeStackItemCount(inputs=4, outputs=1),
     Ops.EXTDELEGATECALL: OpcodeStackItemCount(inputs=3, outputs=1),
     Ops.EXTSTATICCALL: OpcodeStackItemCount(inputs=3, outputs=1),
+    Ops.PAY: OpcodeStackItemCount(inputs=2, outputs=1),
 }
 
 

src/ethereum/osaka/vm/instructions/system.py

@@ -1379,3 +1379,58 @@ def return_contract(evm: Evm) -> None:
 
     # PROGRAM COUNTER
     evm.running = False
+
+
+def pay(evm: Evm) -> None:
+    """
+    Transfer ether to an account.
+
+    Parameters
+    ----------
+    evm :
+        The current EVM frame.
+    """
+    # STACK
+    try:
+        to = to_address_without_mask(pop(evm.stack))
+    except ValueError as e:
+        raise ExceptionalHalt from e
+    value = pop(evm.stack)
+
+    # GAS
+    if to in evm.accessed_addresses:
+        access_gas_cost = GAS_WARM_ACCESS
+    else:
+        evm.accessed_addresses.add(to)
+        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
+
+    create_gas_cost = (
+        Uint(0)
+        if is_account_alive(evm.message.block_env.state, to) or value == 0
+        else GAS_NEW_ACCOUNT
+    )
+
+    transfer_gas_cost = Uint(0) if value == U256(0) else GAS_CALL_VALUE
+
+    charge_gas(evm, access_gas_cost + create_gas_cost + transfer_gas_cost)
+
+    # OPERATION
+    if value > U256(0):
+        try:
+            move_ether(
+                evm.message.block_env.state,
+                evm.message.current_target,
+                to,
+                value,
+            )
+            push(evm.stack, U256(1))
+        except AssertionError:
+            # TODO: This behavior has not been
+            # finalized yet and is simply based on
+            # ongoing discussions. The final update
+            # needs to be made to this based on the
+            # agreed upon spec.
+            push(evm.stack, U256(0))
+
+    # PROGRAM COUNTER
+    evm.pc += Uint(1)