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
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
|
:(scenario "copy_indirect")
# Instructions can read from addresses pointing at other locations using the 'deref' property.
recipe main [
1:address:integer <- copy 2:literal
2:integer <- copy 34:literal
# This loads location 1 as an address and looks up *that* location.
3:integer <- copy 1:address:integer/deref
]
+run: instruction 2
+mem: location 1 is 2
+mem: location 2 is 34
+mem: storing in location 3
:(replace{} "vector<int> read_memory(reagent x)")
vector<int> read_memory(reagent x) {
vector<int> result;
if (x.types[0] == 0) { // literal
result.push_back(to_int(x.name));
return result;
}
x = canonize(x);
int base = to_int(x.name);
size_t size = size_of(x);
for (size_t offset = 0; offset < size; ++offset) {
int val = Memory[base+offset];
trace("mem") << "location " << base+offset << " is " << val;
result.push_back(val);
}
return result;
}
:(scenario "store_indirect")
# similarly, write to addresses pointing at other locations using the 'deref' property
recipe main [
1:address:integer <- copy 2:literal
1:address:integer/deref <- copy 34:literal
]
+run: instruction 1
+mem: location 1 is 2
+mem: storing in location 2
:(replace{} "void write_memory(reagent x, vector<int> data)")
void write_memory(reagent x, vector<int> data) {
x = canonize(x);
int base = to_int(x.name);
if (!Type[x.types[0]].is_array && size_of(x) != data.size())
raise << "size mismatch in storing to " << x.to_string();
for (size_t offset = 0; offset < data.size(); ++offset) {
trace("mem") << "storing in location " << base+offset;
Memory[base+offset] = data[offset];
}
}
:(code)
reagent canonize(reagent x) {
reagent r = x;
while (has_property(r, "deref"))
r = deref(r);
return r;
}
bool has_property(reagent x, string name) {
for (size_t i = 0; i < x.properties.size(); ++i) {
if (x.properties[i].first == name) return true;
}
return false;
}
reagent deref(reagent x) {
reagent result("");
assert(x.types[0] == 2); // address
// compute name
ostringstream out;
out << Memory[to_int(x.name)];
result.name = out.str();
trace("mem") << "location " << x.name << " is " << result.name;
// populate types
copy(++x.types.begin(), x.types.end(), inserter(result.types, result.types.begin()));
// drop-one 'deref'
int i = 0;
int len = x.properties.size();
while (true) {
assert(i < len);
if (x.properties[i].first == "deref") break;
result.properties.push_back(x.properties[i]);
++i;
}
++i; // skip first deref
while (i < len) {
result.properties.push_back(x.properties[i]);
}
return result;
}
:(scenario "get_address_indirect")
# 'get' can read from record address
recipe main [
1:integer <- copy 2:literal
2:integer <- copy 34:literal
3:integer <- copy 35:literal
4:integer <- get 1:address:point/deref, 0:offset
]
+run: instruction 3
+run: address to copy is 2
+run: product 0 is 34
+mem: storing in location 4
:(replace{} "case GET:")
case GET: {
trace("run") << "ingredient 0 is " << instructions[pc].ingredients[0].name;
reagent base = canonize(instructions[pc].ingredients[0]);
int base_address = to_int(base.name);
int base_type = base.types[0];
assert(Type[base_type].is_record);
trace("run") << "ingredient 1 is " << instructions[pc].ingredients[1].name;
assert(instructions[pc].ingredients[1].types.size() == 1);
assert(instructions[pc].ingredients[1].types[0] == 0); // must be literal
size_t offset = to_int(instructions[pc].ingredients[1].name);
int src = base_address;
for (size_t i = 0; i < offset; ++i) {
src += size_of(reagent(Type[base_type].elements[i][0]));
}
trace("run") << "address to copy is " << src;
assert(Type[base_type].is_record);
assert(Type[base_type].elements.size() > offset);
int src_type = Type[base_type].elements[offset][0];
trace("run") << "its type is " << src_type;
ostringstream s;
s << src;
reagent tmp(s.str());
tmp.types.push_back(src_type);
vector<int> result(read_memory(tmp));
trace("run") << "product 0 is " << result[0];
write_memory(instructions[pc].products[0], result);
break;
}
:(scenario "get_indirect")
# 'get' can read from record address
recipe main [
1:integer <- copy 2:literal
2:integer <- copy 34:literal
3:integer <- copy 35:literal
4:integer <- get-address 1:address:point/deref, 0:offset
]
+run: instruction 3
+run: address to copy is 2
+run: product 0 is 2
:(replace{} "case GET_ADDRESS:")
case GET_ADDRESS: {
trace("run") << "ingredient 0 is " << instructions[pc].ingredients[0].name;
reagent base = canonize(instructions[pc].ingredients[0]);
int base_address = to_int(base.name);
int base_type = base.types[0];
assert(Type[base_type].is_record);
trace("run") << "ingredient 1 is " << instructions[pc].ingredients[1].name;
assert(instructions[pc].ingredients[1].types.size() == 1);
assert(instructions[pc].ingredients[1].types[0] == 0); // must be literal
size_t offset = to_int(instructions[pc].ingredients[1].name);
int src = base_address+offset;
trace("run") << "address to copy is " << src;
vector<int> result;
result.push_back(src);
trace("run") << "product 0 is " << result[0];
write_memory(instructions[pc].products[0], result);
break;
}
|