1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
|
// Copyright 2014 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 (
"fmt"
"sync"
"github.com/holiman/uint256"
)
var stackPool = sync.Pool{
New: func() interface{} {
return &Stack{data: make([]uint256.Int, 0, 16)}
},
}
// Stack is an object for basic stack operations. Items popped to the stack are
// expected to be changed and modified. stack does not take care of adding newly
// initialised objects.
type Stack struct {
data []uint256.Int
}
func newstack() *Stack {
return stackPool.Get().(*Stack)
}
func returnStack(s *Stack) {
s.data = s.data[:0]
stackPool.Put(s)
}
// Data returns the underlying uint256.Int array.
func (st *Stack) Data() []uint256.Int {
return st.data
}
func (st *Stack) push(d *uint256.Int) {
// NOTE push limit (1024) is checked in baseCheck
st.data = append(st.data, *d)
}
func (st *Stack) pushN(ds ...uint256.Int) {
// FIXME: Is there a way to pass args by pointers.
st.data = append(st.data, ds...)
}
func (st *Stack) pop() (ret uint256.Int) {
ret = st.data[len(st.data)-1]
st.data = st.data[:len(st.data)-1]
return
}
func (st *Stack) len() int {
return len(st.data)
}
func (st *Stack) swap(n int) {
st.data[st.len()-n], st.data[st.len()-1] = st.data[st.len()-1], st.data[st.len()-n]
}
func (st *Stack) dup(n int) {
st.push(&st.data[st.len()-n])
}
func (st *Stack) peek() *uint256.Int {
return &st.data[st.len()-1]
}
// Back returns the n'th item in stack
func (st *Stack) Back(n int) *uint256.Int {
return &st.data[st.len()-n-1]
}
// Print dumps the content of the stack
func (st *Stack) Print() {
fmt.Println("### stack ###")
if len(st.data) > 0 {
for i, val := range st.data {
fmt.Printf("%-3d %v\n", i, val)
}
} else {
fmt.Println("-- empty --")
}
fmt.Println("#############")
}
var rStackPool = sync.Pool{
New: func() interface{} {
return &ReturnStack{data: make([]uint32, 0, 10)}
},
}
// ReturnStack is an object for basic return stack operations.
type ReturnStack struct {
data []uint32
}
func newReturnStack() *ReturnStack {
return rStackPool.Get().(*ReturnStack)
}
func returnRStack(rs *ReturnStack) {
rs.data = rs.data[:0]
rStackPool.Put(rs)
}
func (st *ReturnStack) push(d uint32) {
st.data = append(st.data, d)
}
// A uint32 is sufficient as for code below 4.2G
func (st *ReturnStack) pop() (ret uint32) {
ret = st.data[len(st.data)-1]
st.data = st.data[:len(st.data)-1]
return
}
|