ethereum.forks.bpo5.vm.instructions.storageethereum.forks.amsterdam.vm.instructions.storage
Ethereum Virtual Machine (EVM) Storage Instructions.
.. contents:: Table of Contents :backlinks: none :local:
Introduction
Implementations of the EVM storage related instructions.
sload ¶
Loads to the stack, the value corresponding to a certain key from the storage of the current account.
Parameters
evm : The current EVM frame.
def sload(evm: Evm) -> None:
| 37 | """ |
|---|---|
| 38 | Loads to the stack, the value corresponding to a certain key from the |
| 39 | storage of the current account. |
| 40 | |
| 41 | Parameters |
| 42 | ---------- |
| 43 | evm : |
| 44 | The current EVM frame. |
| 45 | |
| 46 | """ |
| 47 | # STACK |
| 48 | key = pop(evm.stack).to_be_bytes32() |
| 49 | |
| 50 | # GAS |
| 51 | if (evm.message.current_target, key) in evm.accessed_storage_keys: |
| 52 | charge_gas(evm, GasCosts.WARM_ACCESS) |
| 53 | else: |
| 54 | evm.accessed_storage_keys.add((evm.message.current_target, key)) |
| 55 | charge_gas(evm, GasCosts.COLD_STORAGE_ACCESS) |
| 56 | |
| 57 | # OPERATION |
| 54 | value = get_storage( |
| 55 | evm.message.block_env.state, evm.message.current_target, key |
| 56 | ) |
| 58 | tx_state = evm.message.tx_env.state |
| 59 | value = get_storage(tx_state, evm.message.current_target, key) |
| 60 | |
| 61 | push(evm.stack, value) |
| 62 | |
| 63 | # PROGRAM COUNTER |
| 64 | evm.pc += Uint(1) |
sstore ¶
Stores a value at a certain key in the current context's storage.
Parameters
evm : The current EVM frame.
def sstore(evm: Evm) -> None:
| 68 | """ |
|---|---|
| 69 | Stores a value at a certain key in the current context's storage. |
| 70 | |
| 71 | Parameters |
| 72 | ---------- |
| 73 | evm : |
| 74 | The current EVM frame. |
| 75 | |
| 76 | """ |
| 77 | if evm.message.is_static: |
| 78 | raise WriteInStaticContext |
| 79 | |
| 80 | # STACK |
| 81 | key = pop(evm.stack).to_be_bytes32() |
| 82 | new_value = pop(evm.stack) |
| 77 | if evm.gas_left <= GasCosts.CALL_STIPEND: |
| 78 | raise OutOfGasError |
| 83 | |
| 80 | state = evm.message.block_env.state |
| 81 | original_value = get_storage_original( |
| 82 | state, evm.message.current_target, key |
| 84 | # check we have at least the stipend gas |
| 85 | check_gas(evm, GasCosts.CALL_STIPEND + Uint(1)) |
| 86 | |
| 87 | tx_state = evm.message.tx_env.state |
| 88 | original_value = get_storage_original( |
| 89 | tx_state, evm.message.current_target, key |
| 90 | ) |
| 84 | current_value = get_storage(state, evm.message.current_target, key) |
| 91 | current_value = get_storage(tx_state, evm.message.current_target, key) |
| 92 | |
| 93 | state_gas_storage_set = STATE_BYTES_PER_STORAGE_SET * COST_PER_STATE_BYTE |
| 94 | gas_cost = Uint(0) |
| 95 | |
| 96 | if (evm.message.current_target, key) not in evm.accessed_storage_keys: |
| 97 | evm.accessed_storage_keys.add((evm.message.current_target, key)) |
| 98 | gas_cost += GasCosts.COLD_STORAGE_ACCESS |
| 99 | |
| 100 | needs_state_gas = False |
| 101 | if original_value == current_value and current_value != new_value: |
| 102 | if original_value == 0: |
| 94 | gas_cost += GasCosts.STORAGE_SET |
| 95 | else: |
| 96 | gas_cost += ( |
| 97 | GasCosts.COLD_STORAGE_WRITE - GasCosts.COLD_STORAGE_ACCESS |
| 98 | ) |
| 103 | needs_state_gas = True |
| 104 | # charge regular cost for the operation, even when we |
| 105 | # already charge state gas for state creation |
| 106 | gas_cost += GasCosts.COLD_STORAGE_WRITE - GasCosts.COLD_STORAGE_ACCESS |
| 107 | else: |
| 108 | gas_cost += GasCosts.WARM_ACCESS |
| 109 | |
| 110 | # Refund Counter Calculation |
| 111 | if current_value != new_value: |
| 112 | if original_value != 0 and current_value != 0 and new_value == 0: |
| 113 | # Storage is cleared for the first time in the transaction |
| 114 | evm.refund_counter += GasCosts.REFUND_STORAGE_CLEAR |
| 115 | |
| 116 | if original_value != 0 and current_value == 0: |
| 117 | # Gas refund issued earlier to be reversed |
| 118 | evm.refund_counter -= GasCosts.REFUND_STORAGE_CLEAR |
| 119 | |
| 120 | if original_value == new_value: |
| 121 | # Storage slot being restored to its original value |
| 122 | if original_value == 0: |
| 115 | # Slot was originally empty and was SET earlier |
| 116 | evm.refund_counter += int( |
| 117 | GasCosts.STORAGE_SET - GasCosts.WARM_ACCESS |
| 118 | ) |
| 119 | else: |
| 120 | # Slot was originally non-empty and was UPDATED earlier |
| 121 | evm.refund_counter += int( |
| 122 | GasCosts.COLD_STORAGE_WRITE |
| 123 | - GasCosts.COLD_STORAGE_ACCESS |
| 124 | - GasCosts.WARM_ACCESS |
| 125 | ) |
| 123 | # Slot set then cleared: refund the state gas charge. |
| 124 | credit_state_gas_refund(evm, state_gas_storage_set) |
| 125 | evm.refund_counter += int( |
| 126 | GasCosts.COLD_STORAGE_WRITE |
| 127 | - GasCosts.COLD_STORAGE_ACCESS |
| 128 | - GasCosts.WARM_ACCESS |
| 129 | ) |
| 130 | |
| 127 | charge_gas(evm, gas_cost) |
| 128 | if evm.message.is_static: |
| 129 | raise WriteInStaticContext |
| 130 | set_storage(state, evm.message.current_target, key, new_value) |
| 131 | # Charge regular gas before state gas so that a regular-gas OOG |
| 132 | # does not consume state gas that would inflate the parent's |
| 133 | # reservoir on frame failure. |
| 134 | charge_gas(evm, gas_cost) |
| 135 | if needs_state_gas: |
| 136 | charge_state_gas(evm, state_gas_storage_set) |
| 137 | set_storage(tx_state, evm.message.current_target, key, new_value) |
| 138 | |
| 139 | # PROGRAM COUNTER |
| 140 | evm.pc += Uint(1) |
tload ¶
Loads to the stack, the value corresponding to a certain key from the transient storage of the current account.
Parameters
evm : The current EVM frame.
def tload(evm: Evm) -> None:
| 144 | """ |
|---|---|
| 145 | Loads to the stack, the value corresponding to a certain key from the |
| 146 | transient storage of the current account. |
| 147 | |
| 148 | Parameters |
| 149 | ---------- |
| 150 | evm : |
| 151 | The current EVM frame. |
| 152 | |
| 153 | """ |
| 154 | # STACK |
| 155 | key = pop(evm.stack).to_be_bytes32() |
| 156 | |
| 157 | # GAS |
| 158 | charge_gas(evm, GasCosts.WARM_ACCESS) |
| 159 | |
| 160 | # OPERATION |
| 154 | value = get_transient_storage( |
| 155 | evm.message.tx_env.transient_storage, evm.message.current_target, key |
| 161 | value = get_transient_storage( |
| 162 | evm.message.tx_env.state, evm.message.current_target, key |
| 163 | ) |
| 164 | push(evm.stack, value) |
| 165 | |
| 166 | # PROGRAM COUNTER |
| 167 | evm.pc += Uint(1) |
tstore ¶
Stores a value at a certain key in the current context's transient storage.
Parameters
evm : The current EVM frame.
def tstore(evm: Evm) -> None:
| 171 | """ |
|---|---|
| 172 | Stores a value at a certain key in the current context's transient storage. |
| 173 | |
| 174 | Parameters |
| 175 | ---------- |
| 176 | evm : |
| 177 | The current EVM frame. |
| 178 | |
| 179 | """ |
| 180 | if evm.message.is_static: |
| 181 | raise WriteInStaticContext |
| 182 | |
| 183 | # STACK |
| 184 | key = pop(evm.stack).to_be_bytes32() |
| 185 | new_value = pop(evm.stack) |
| 186 | |
| 187 | # GAS |
| 188 | charge_gas(evm, GasCosts.WARM_ACCESS) |
| 179 | if evm.message.is_static: |
| 180 | raise WriteInStaticContext |
| 181 | set_transient_storage( |
| 182 | evm.message.tx_env.transient_storage, |
| 189 | set_transient_storage( |
| 190 | evm.message.tx_env.state, |
| 191 | evm.message.current_target, |
| 192 | key, |
| 193 | new_value, |
| 194 | ) |
| 195 | |
| 196 | # PROGRAM COUNTER |
| 197 | evm.pc += Uint(1) |