mirror of
https://gitlab.com/pulsechaincom/go-pulse.git
synced 2024-12-22 03:30:35 +00:00
5c9cbc218a
Implements [EIP 5656](https://eips.ethereum.org/EIPS/eip-5656), MCOPY instruction, and enables it for Cancun. --------- Co-authored-by: Martin Holst Swende <martin@swende.se>
117 lines
3.2 KiB
Go
117 lines
3.2 KiB
Go
// Copyright 2015 The go-ethereum Authors
|
|
// This file is part of the go-ethereum library.
|
|
//
|
|
// The go-ethereum library is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU Lesser General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// The go-ethereum library is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU Lesser General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU Lesser General Public License
|
|
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
package vm
|
|
|
|
import (
|
|
"github.com/holiman/uint256"
|
|
)
|
|
|
|
// Memory implements a simple memory model for the ethereum virtual machine.
|
|
type Memory struct {
|
|
store []byte
|
|
lastGasCost uint64
|
|
}
|
|
|
|
// NewMemory returns a new memory model.
|
|
func NewMemory() *Memory {
|
|
return &Memory{}
|
|
}
|
|
|
|
// Set sets offset + size to value
|
|
func (m *Memory) Set(offset, size uint64, value []byte) {
|
|
// It's possible the offset is greater than 0 and size equals 0. This is because
|
|
// the calcMemSize (common.go) could potentially return 0 when size is zero (NO-OP)
|
|
if size > 0 {
|
|
// length of store may never be less than offset + size.
|
|
// The store should be resized PRIOR to setting the memory
|
|
if offset+size > uint64(len(m.store)) {
|
|
panic("invalid memory: store empty")
|
|
}
|
|
copy(m.store[offset:offset+size], value)
|
|
}
|
|
}
|
|
|
|
// Set32 sets the 32 bytes starting at offset to the value of val, left-padded with zeroes to
|
|
// 32 bytes.
|
|
func (m *Memory) Set32(offset uint64, val *uint256.Int) {
|
|
// length of store may never be less than offset + size.
|
|
// The store should be resized PRIOR to setting the memory
|
|
if offset+32 > uint64(len(m.store)) {
|
|
panic("invalid memory: store empty")
|
|
}
|
|
// Fill in relevant bits
|
|
b32 := val.Bytes32()
|
|
copy(m.store[offset:], b32[:])
|
|
}
|
|
|
|
// Resize resizes the memory to size
|
|
func (m *Memory) Resize(size uint64) {
|
|
if uint64(m.Len()) < size {
|
|
m.store = append(m.store, make([]byte, size-uint64(m.Len()))...)
|
|
}
|
|
}
|
|
|
|
// GetCopy returns offset + size as a new slice
|
|
func (m *Memory) GetCopy(offset, size int64) (cpy []byte) {
|
|
if size == 0 {
|
|
return nil
|
|
}
|
|
|
|
if len(m.store) > int(offset) {
|
|
cpy = make([]byte, size)
|
|
copy(cpy, m.store[offset:offset+size])
|
|
|
|
return
|
|
}
|
|
|
|
return
|
|
}
|
|
|
|
// GetPtr returns the offset + size
|
|
func (m *Memory) GetPtr(offset, size int64) []byte {
|
|
if size == 0 {
|
|
return nil
|
|
}
|
|
|
|
if len(m.store) > int(offset) {
|
|
return m.store[offset : offset+size]
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// Len returns the length of the backing slice
|
|
func (m *Memory) Len() int {
|
|
return len(m.store)
|
|
}
|
|
|
|
// Data returns the backing slice
|
|
func (m *Memory) Data() []byte {
|
|
return m.store
|
|
}
|
|
|
|
// Copy copies data from the src position slice into the dst position.
|
|
// The source and destination may overlap.
|
|
// OBS: This operation assumes that any necessary memory expansion has already been performed,
|
|
// and this method may panic otherwise.
|
|
func (m *Memory) Copy(dst, src, len uint64) {
|
|
if len == 0 {
|
|
return
|
|
}
|
|
copy(m.store[dst:], m.store[src:src+len])
|
|
}
|