//: Instructions can read from addresses pointing at other locations using the
//: 'lookup' property.
:(scenario copy_indirect)
def main [
1:address:number <- copy 2/unsafe
2:number <- copy 34
# This loads location 1 as an address and looks up *that* location.
3:number <- copy 1:address:number/lookup
]
+mem: storing 34 in location 3
:(before "long long int base = x.value" following "vector<double> read_memory(reagent x)")
canonize(x);
//: similarly, write to addresses pointing at other locations using the
//: 'lookup' property
:(scenario store_indirect)
def main [
1:address:number <- copy 2/unsafe
1:address:number/lookup <- copy 34
]
+mem: storing 34 in location 2
:(before "long long int base = x.value" following "void write_memory(reagent x, const vector<double>& data)")
canonize(x);
if (x.value == 0) {
raise << "can't write to location 0 in '" << to_string(current_instruction()) << "'\n" << end();
return;
}
//: writes to address 0 always loudly fail
:(scenario store_to_0_fails)
% Hide_errors = true;
def main [
1:address:number <- copy 0
1:address:number/lookup <- copy 34
]
-mem: storing 34 in location 0
+error: can't write to location 0 in '1:address:number/lookup <- copy 34'
:(code)
void canonize(reagent& x) {
if (is_literal(x)) return;
// End canonize(x) Special-cases
while (has_property(x, "lookup"))
lookup_memory(x);
}
void lookup_memory(reagent& x) {
if (!x.type || x.type->value != get(Type_ordinal, "address")) {
raise << maybe(current_recipe_name()) << "tried to /lookup " << x.original_string << " but it isn't an address\n" << end();
return;
}
// compute value
if (x.value == 0) {
raise << maybe(current_recipe_name()) << "tried to /lookup 0\n" << end();
return;
}
trace(9999, "mem") << "location " << x.value << " is " << no_scientific(get_or_insert(Memory, x.value)) << end();
x.set_value(get_or_insert(Memory, x.value));
drop_from_type(x, "address");
// End Drop Address In lookup_memory(x)
drop_one_lookup(x);
}
:(scenario canonize_non_pointer_fails_without_crashing)
% Hide_errors = true;
def foo [
1:address:number <- get-address *p, x:offset
]
# don't crash
:(after "bool types_strictly_match(reagent to, reagent from)")
if (!canonize_type(to)) return false;
if (!canonize_type(from)) return false;
:(after "bool is_mu_array(reagent r)")
if (!canonize_type(r)) return false;
:(after "bool is_mu_address(reagent r)")
if (!canonize_type(r)) return false;
:(after "bool is_mu_number(reagent r)")
if (!canonize_type(r)) return false;
:(after "bool is_mu_boolean(reagent r)")
if (!canonize_type(r)) return false;
:(after "Update product While Type-checking Merge")
if (!canonize_type(product)) continue;
:(code)
bool canonize_type(reagent& r) {
while (has_property(r, "lookup")) {
if (!r.type || r.type->value != get(Type_ordinal, "address")) {
raise << "can't lookup non-address: " << to_string(r) << ": " << to_string(r.type) << '\n' << end();
return false;
}
drop_from_type(r, "address");
// End Drop Address In canonize_type(r)
drop_one_lookup(r);
}
return true;
}
void drop_from_type(reagent& r, string expected_type) {
if (!r.type) {
raise << "can't drop " << expected_type << " from " << to_string(r) << '\n' << end();
return;
}
if (r.type->name != expected_type) {
raise << "can't drop2 " << expected_type << " from " << to_string(r) << '\n' << end();
return;
}
type_tree* tmp = r.type;
r.type = tmp->right;
tmp->right = NULL;
delete tmp;
}
void drop_one_lookup(reagent& r) {
for (vector<pair<string, string_tree*> >::iterator p = r.properties.begin(); p != r.properties.end(); ++p) {
if (p->first == "lookup") {
r.properties.erase(p);
return;
}
}
assert(false);
}
//:: 'get' can read from container address
:(scenario get_indirect)
def main [
1:number <- copy 2
2:number <- copy 34
3:number <- copy 35
4:number <- get 1:address:point/lookup, 0:offset
]
+mem: storing 34 in location 4
:(scenario get_indirect2)
def main [
1:number <- copy 2
2:number <- copy 34
3:number <- copy 35
4:address:number <- copy 5/unsafe
*4:address:number <- get 1:address:point/lookup, 0:offset
]
+mem: storing 34 in location 5
:(scenario include_nonlookup_properties)
def main [
1:number <- copy 2
2:number <- copy 34
3:number <- copy 35
4:number <- get 1:address:point/lookup/foo, 0:offset
]
+mem: storing 34 in location 4
:(after "Update GET base in Check")
if (!canonize_type(base)) break;
:(after "Update GET product in Check")
if (!canonize_type(product)) break;
:(after "Update GET base in Run")
canonize(base);
:(scenario get_address_indirect)
# 'get' can read from container address
def main [
1:number <- copy 2
2:number <- copy 34
3:number <- copy 35
4:address:number <- get-address 1:address:point/lookup, 0:offset
]
+mem: storing 2 in location 4
:(after "Update GET_ADDRESS base in Check")
if (!canonize_type(base)) break;
:(after "Update GET_ADDRESS product in Check")
if (!canonize_type(base)) break;
:(after "Update GET_ADDRESS base in Run")
canonize(base);
//:: abbreviation for '/lookup': a prefix '*'
:(scenario lookup_abbreviation)
def main [
1:address:number <- copy 2/unsafe
2:number <- copy 34
3:number <- copy *1:address:number
]
+parse: ingredient: 1: ("address" "number"), {"lookup": ()}
+mem: storing 34 in location 3
:(before "End Parsing reagent")
{
while (!name.empty() && name.at(0) == '*') {
name.erase(0, 1);
properties.push_back(pair<string, string_tree*>("lookup", NULL));
}
if (name.empty())
raise << "illegal name " << original_string << '\n' << end();
}
//:: helpers for debugging
:(before "End Primitive Recipe Declarations")
_DUMP,
:(before "End Primitive Recipe Numbers")
put(Recipe_ordinal, "$dump", _DUMP);
:(before "End Primitive Recipe Implementations")
case _DUMP: {
reagent after_canonize = current_instruction().ingredients.at(0);
canonize(after_canonize);
cerr << maybe(current_recipe_name()) << current_instruction().ingredients.at(0).name << ' ' << no_scientific(current_instruction().ingredients.at(0).value) << " => " << no_scientific(after_canonize.value) << " => " << no_scientific(get_or_insert(Memory, after_canonize.value)) << '\n';
break;
}
//: grab an address, and then dump its value at intervals
//: useful for tracking down memory corruption (writing to an out-of-bounds address)
:(before "End Globals")
long long int foo = -1;
:(before "End Primitive Recipe Declarations")
_FOO,
:(before "End Primitive Recipe Numbers")
put(Recipe_ordinal, "$foo", _FOO);
:(before "End Primitive Recipe Implementations")
case _FOO: {
if (current_instruction().ingredients.empty()) {
if (foo != -1) cerr << foo << ": " << no_scientific(get_or_insert(Memory, foo)) << '\n';
else cerr << '\n';
}
else {
reagent tmp = current_instruction().ingredients.at(0);
canonize(tmp);
foo = tmp.value;
}
break;
}