core/tracing, core/vm: add ContractCode to the OpContext (ethereum#30466)

Extends the opcontext interface to include accessor for code being executed in current context. While it is possible to get the code via `statedb.GetCode`, that approach doesn't work for initcode.

Author: kchojn

core/tracing/hooks.go

@@ -34,6 +34,7 @@ type OpContext interface {
 	Address() common.Address
 	CallValue() *uint256.Int
 	CallInput() []byte
+	ContractCode() []byte
 }
 
 // StateDB gives tracers access to the whole state.

core/vm/interpreter.go

@@ -84,6 +84,11 @@ func (ctx *ScopeContext) CallInput() []byte {
 	return ctx.Contract.Input
 }
 
+// ContractCode returns the code of the contract being executed.
+func (ctx *ScopeContext) ContractCode() []byte {
+	return ctx.Contract.Code
+}
+
 // EVMInterpreter represents an EVM interpreter
 type EVMInterpreter struct {
 	evm   *EVM