Merge pull request #173 from ethereum/status-code

EVM-C: introduce new status codes

include/evm.h

@@ -140,22 +140,29 @@ typedef void (*evm_get_block_hash_fn)(struct evm_uint256be* result,
                                       int64_t number);
 
 /// The execution status code.
-///
-/// @todo: Add status code for out-of-buffer access.
 enum evm_status_code {
     EVM_SUCCESS = 0,               ///< Execution finished with success.
     EVM_FAILURE = 1,               ///< Generic execution failure.
     EVM_OUT_OF_GAS = 2,
-    EVM_BAD_INSTRUCTION = 3,
+    EVM_UNDEFINED_INSTRUCTION = 3, ///< Unknown instruction encountered by the VM.
     EVM_BAD_JUMP_DESTINATION = 4,
     EVM_STACK_OVERFLOW = 5,
     EVM_STACK_UNDERFLOW = 6,
     EVM_REVERT = 7,                ///< Execution terminated with REVERT opcode.
-    /// Tried to execute an operation which is restricted in static mode.
 
+    /// Tried to execute an operation which is restricted in static mode.
+    ///
     /// @todo Avoid _ERROR suffix that suggests fatal error.
     EVM_STATIC_MODE_ERROR = 8,
 
+    /// The dedicated INVALID instruction was hit.
+    EVM_INVALID_INSTRUCTION = 9,
+
+    /// Tried to read outside memory bounds.
+    ///
+    /// An example is RETURNDATACOPY reading past the available buffer.
+    EVM_INVALID_MEMORY_ACCESS = 10,
+
     /// The EVM rejected the execution of the given code or message.
     ///
     /// This error SHOULD be used to signal that the EVM is not able to or