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|
//: Containers contain a fixed number of elements of different types.
:(before "End Mu Types Initialization")
//: We'll use this container as a running example, with two number elements.
type_ordinal point = put(Type_ordinal, "point", Next_type_ordinal++);
get_or_insert(Type, point).size = 2;
get(Type, point).kind = CONTAINER;
get(Type, point).name = "point";
get(Type, point).elements.push_back(new type_tree(number));
get(Type, point).element_names.push_back("x");
get(Type, point).elements.push_back(new type_tree(number));
get(Type, point).element_names.push_back("y");
//: Containers can be copied around with a single instruction just like
//: numbers, no matter how large they are.
//: Tests in this layer often explicitly setup memory before reading it as a
//: container. Don't do this in general. I'm tagging exceptions with /raw to
//: avoid errors.
:(scenario copy_multiple_locations)
recipe main [
1:number <- copy 34
2:number <- copy 35
3:point <- copy 1:point/raw # unsafe
]
+mem: storing 34 in location 3
+mem: storing 35 in location 4
//: trying to copy to a differently-typed destination will fail
:(scenario copy_checks_size)
% Hide_errors = true;
recipe main [
2:point <- copy 1:number
]
+error: main: can't copy 1:number to 2:point; types don't match
:(before "End Mu Types Initialization")
// A more complex container, containing another container as one of its
// elements.
type_ordinal point_number = put(Type_ordinal, "point-number", Next_type_ordinal++);
get_or_insert(Type, point_number).size = 2;
get(Type, point_number).kind = CONTAINER;
get(Type, point_number).name = "point-number";
get(Type, point_number).elements.push_back(new type_tree(point));
get(Type, point_number).element_names.push_back("xy");
get(Type, point_number).elements.push_back(new type_tree(number));
get(Type, point_number).element_names.push_back("z");
:(scenario copy_handles_nested_container_elements)
recipe main [
12:number <- copy 34
13:number <- copy 35
14:number <- copy 36
15:point-number <- copy 12:point-number/raw # unsafe
]
+mem: storing 36 in location 17
//: Containers can be checked for equality with a single instruction just like
//: numbers, no matter how large they are.
:(scenario compare_multiple_locations)
recipe main [
1:number <- copy 34 # first
2:number <- copy 35
3:number <- copy 36
4:number <- copy 34 # second
5:number <- copy 35
6:number <- copy 36
7:boolean <- equal 1:point-number/raw, 4:point-number/raw # unsafe
]
+mem: storing 1 in location 7
:(scenario compare_multiple_locations_2)
recipe main [
1:number <- copy 34 # first
2:number <- copy 35
3:number <- copy 36
4:number <- copy 34 # second
5:number <- copy 35
6:number <- copy 37 # different
7:boolean <- equal 1:point-number/raw, 4:point-number/raw # unsafe
]
+mem: storing 0 in location 7
:(before "End size_of(type) Cases")
if (type->value == -1) {
// error value, but we'll raise it elsewhere
return 1;
}
if (type->value == 0) {
assert(!type->left && !type->right);
return 1;
}
type_info t = get(Type, type->value);
if (t.kind == CONTAINER) {
// size of a container is the sum of the sizes of its elements
long long int result = 0;
for (long long int i = 0; i < SIZE(t.elements); ++i) {
// todo: strengthen assertion to disallow mutual type recursion
if (t.elements.at(i)->value == type->value) {
raise_error << "container " << t.name << " can't include itself as a member\n" << end();
return 0;
}
// End size_of(type) Container Cases
result += size_of(t.elements.at(i));
}
return result;
}
:(scenario stash_container)
recipe main [
1:number <- copy 34 # first
2:number <- copy 35
3:number <- copy 36
stash [foo:], 1:point-number/raw
]
+app: foo: 34 35 36
//:: To access elements of a container, use 'get'
:(scenario get)
recipe main [
12:number <- copy 34
13:number <- copy 35
15:number <- get 12:point/raw, 1:offset # unsafe
]
+mem: storing 35 in location 15
:(before "End Primitive Recipe Declarations")
GET,
:(before "End Primitive Recipe Numbers")
put(Recipe_ordinal, "get", GET);
:(before "End Primitive Recipe Checks")
case GET: {
if (SIZE(inst.ingredients) != 2) {
raise_error << maybe(get(Recipe, r).name) << "'get' expects exactly 2 ingredients in '" << inst.to_string() << "'\n" << end();
break;
}
reagent base = inst.ingredients.at(0); // new copy for every invocation
// Update GET base in Check
if (!base.type || !base.type->value || !contains_key(Type, base.type->value) || get(Type, base.type->value).kind != CONTAINER) {
raise_error << maybe(get(Recipe, r).name) << "first ingredient of 'get' should be a container, but got " << inst.ingredients.at(0).original_string << '\n' << end();
break;
}
type_ordinal base_type = base.type->value;
reagent offset = inst.ingredients.at(1);
if (!is_literal(offset) || !is_mu_scalar(offset)) {
raise_error << maybe(get(Recipe, r).name) << "second ingredient of 'get' should have type 'offset', but got " << inst.ingredients.at(1).original_string << '\n' << end();
break;
}
long long int offset_value = 0;
if (is_integer(offset.name)) // later layers permit non-integer offsets
offset_value = to_integer(offset.name);
else
offset_value = offset.value;
if (offset_value < 0 || offset_value >= SIZE(get(Type, base_type).elements)) {
raise_error << maybe(get(Recipe, r).name) << "invalid offset " << offset_value << " for " << get(Type, base_type).name << '\n' << end();
break;
}
if (inst.products.empty()) break;
reagent product = inst.products.at(0);
// Update GET product in Check
const reagent element = element_type(base, offset_value);
if (!types_coercible(product, element)) {
raise_error << maybe(get(Recipe, r).name) << "'get " << base.original_string << ", " << offset.original_string << "' should write to " << debug_string(element.type) << " but " << product.name << " has type " << debug_string(product.type) << '\n' << end();
break;
}
break;
}
:(before "End Primitive Recipe Implementations")
case GET: {
reagent base = current_instruction().ingredients.at(0);
// Update GET base in Run
long long int base_address = base.value;
if (base_address == 0) {
raise_error << maybe(current_recipe_name()) << "tried to access location 0 in '" << current_instruction().to_string() << "'\n" << end();
break;
}
type_ordinal base_type = base.type->value;
long long int offset = ingredients.at(1).at(0);
if (offset < 0 || offset >= SIZE(get(Type, base_type).elements)) break; // copied from Check above
long long int src = base_address;
for (long long int i = 0; i < offset; ++i) {
// End GET field Cases
src += size_of(get(Type, base_type).elements.at(i));
}
trace(9998, "run") << "address to copy is " << src << end();
reagent tmp = element_type(base, offset);
tmp.set_value(src);
trace(9998, "run") << "its type is " << debug_string(tmp.type) << end();
products.push_back(read_memory(tmp));
break;
}
:(code)
const reagent element_type(const reagent& canonized_base, long long int offset_value) {
assert(offset_value >= 0);
assert(contains_key(Type, canonized_base.type->value));
assert(!get(Type, canonized_base.type->value).name.empty());
const type_info& info = get(Type, canonized_base.type->value);
assert(info.kind == CONTAINER);
reagent element;
element.type = new type_tree(*info.elements.at(offset_value));
// End element_type Special-cases
return element;
}
:(scenario get_handles_nested_container_elements)
recipe main [
12:number <- copy 34
13:number <- copy 35
14:number <- copy 36
15:number <- get 12:point-number/raw, 1:offset # unsafe
]
+mem: storing 36 in location 15
:(scenario get_out_of_bounds)
% Hide_errors = true;
recipe main [
12:number <- copy 34
13:number <- copy 35
14:number <- copy 36
get 12:point-number/raw, 2:offset # point-number occupies 3 locations but has only 2 fields; out of bounds
]
+error: main: invalid offset 2 for point-number
:(scenario get_out_of_bounds_2)
% Hide_errors = true;
recipe main [
12:number <- copy 34
13:number <- copy 35
14:number <- copy 36
get 12:point-number/raw, -1:offset
]
+error: main: invalid offset -1 for point-number
:(scenario get_product_type_mismatch)
% Hide_errors = true;
recipe main [
12:number <- copy 34
13:number <- copy 35
14:number <- copy 36
15:address:number <- get 12:point-number/raw, 1:offset
]
+error: main: 'get 12:point-number/raw, 1:offset' should write to number but 15 has type <address : <number : <>>>
//: we might want to call 'get' without saving the results, say in a sandbox
:(scenario get_without_product)
recipe main [
12:number <- copy 34
13:number <- copy 35
get 12:point/raw, 1:offset # unsafe
]
# just don't die
//:: To write to elements of containers, you need their address.
:(scenario get_address)
recipe main [
12:number <- copy 34
13:number <- copy 35
15:address:number <- get-address 12:point/raw, 1:offset # unsafe
]
+mem: storing 13 in location 15
:(before "End Primitive Recipe Declarations")
GET_ADDRESS,
:(before "End Primitive Recipe Numbers")
put(Recipe_ordinal, "get-address", GET_ADDRESS);
:(before "End Primitive Recipe Checks")
case GET_ADDRESS: {
if (SIZE(inst.ingredients) != 2) {
raise_error << maybe(get(Recipe, r).name) << "'get-address' expects exactly 2 ingredients in '" << inst.to_string() << "'\n" << end();
break;
}
reagent base = inst.ingredients.at(0);
// Update GET_ADDRESS base in Check
if (!base.type || !base.type->value || !contains_key(Type, base.type->value) || get(Type, base.type->value).kind != CONTAINER) {
raise_error << maybe(get(Recipe, r).name) << "first ingredient of 'get-address' should be a container, but got " << inst.ingredients.at(0).original_string << '\n' << end();
break;
}
type_ordinal base_type = base.type->value;
reagent offset = inst.ingredients.at(1);
if (!is_literal(offset) || !is_mu_scalar(offset)) {
raise_error << maybe(get(Recipe, r).name) << "second ingredient of 'get' should have type 'offset', but got " << inst.ingredients.at(1).original_string << '\n' << end();
break;
}
long long int offset_value = 0;
if (is_integer(offset.name)) { // later layers permit non-integer offsets
offset_value = to_integer(offset.name);
if (offset_value < 0 || offset_value >= SIZE(get(Type, base_type).elements)) {
raise_error << maybe(get(Recipe, r).name) << "invalid offset " << offset_value << " for " << get(Type, base_type).name << '\n' << end();
break;
}
}
else {
offset_value = offset.value;
}
reagent product = inst.products.at(0);
// Update GET_ADDRESS product in Check
// same type as for GET..
reagent element = element_type(base, offset_value);
// ..except for an address at the start
element.type = new type_tree(get(Type_ordinal, "address"), element.type);
if (!types_coercible(product, element)) {
raise_error << maybe(get(Recipe, r).name) << "'get-address " << base.original_string << ", " << offset.original_string << "' should write to " << debug_string(element.type) << " but " << product.name << " has type " << debug_string(product.type) << '\n' << end();
break;
}
break;
}
:(before "End Primitive Recipe Implementations")
case GET_ADDRESS: {
reagent base = current_instruction().ingredients.at(0);
// Update GET_ADDRESS base in Run
long long int base_address = base.value;
if (base_address == 0) {
raise_error << maybe(current_recipe_name()) << "tried to access location 0 in '" << current_instruction().to_string() << "'\n" << end();
break;
}
type_ordinal base_type = base.type->value;
long long int offset = ingredients.at(1).at(0);
if (offset < 0 || offset >= SIZE(get(Type, base_type).elements)) break; // copied from Check above
long long int result = base_address;
for (long long int i = 0; i < offset; ++i) {
// End GET_ADDRESS field Cases
result += size_of(get(Type, base_type).elements.at(i));
}
trace(9998, "run") << "address to copy is " << result << end();
products.resize(1);
products.at(0).push_back(result);
break;
}
:(scenario get_address_out_of_bounds)
% Hide_errors = true;
recipe main [
12:number <- copy 34
13:number <- copy 35
14:number <- copy 36
get-address 12:point-number/raw, 2:offset # point-number occupies 3 locations but has only 2 fields; out of bounds
]
+error: main: invalid offset 2 for point-number
:(scenario get_address_out_of_bounds_2)
% Hide_errors = true;
recipe main [
12:number <- copy 34
13:number <- copy 35
14:number <- copy 36
get-address 12:point-number/raw, -1:offset
]
+error: main: invalid offset -1 for point-number
:(scenario get_address_product_type_mismatch)
% Hide_errors = true;
container boolbool [
x:boolean
y:boolean
]
recipe main [
12:boolean <- copy 1
13:boolean <- copy 0
15:boolean <- get-address 12:boolbool, 1:offset
]
+error: main: 'get-address 12:boolbool, 1:offset' should write to <address : <boolean : <>>> but 15 has type boolean
//:: Allow containers to be defined in mu code.
:(scenarios load)
:(scenario container)
container foo [
x:number
y:number
]
+parse: --- defining container foo
+parse: element name: x
+parse: type: 1
+parse: element name: y
+parse: type: 1
:(scenario container_use_before_definition)
container foo [
x:number
y:bar
]
container bar [
x:number
y:number
]
+parse: --- defining container foo
+parse: type number: 1000
+parse: element name: x
+parse: type: 1
+parse: element name: y
+parse: type: 1001
+parse: --- defining container bar
+parse: type number: 1001
:(before "End Command Handlers")
else if (command == "container") {
insert_container(command, CONTAINER, in);
}
:(code)
void insert_container(const string& command, kind_of_type kind, istream& in) {
skip_whitespace_but_not_newline(in);
string name = next_word(in);
// End container Name Refinements
trace(9991, "parse") << "--- defining " << command << ' ' << name << end();
if (!contains_key(Type_ordinal, name)
|| get(Type_ordinal, name) == 0) {
put(Type_ordinal, name, Next_type_ordinal++);
}
trace(9999, "parse") << "type number: " << get(Type_ordinal, name) << end();
skip_bracket(in, "'container' must begin with '['");
type_info& info = get_or_insert(Type, get(Type_ordinal, name));
Recently_added_types.push_back(get(Type_ordinal, name));
info.name = name;
info.kind = kind;
while (has_data(in)) {
skip_whitespace_and_comments(in);
string element = next_word(in);
if (element == "]") break;
// End insert_container Special Definitions(element)
istringstream inner(element);
info.element_names.push_back(slurp_until(inner, ':'));
trace(9993, "parse") << " element name: " << info.element_names.back() << end();
type_tree* new_type = NULL;
for (type_tree** curr_type = &new_type; has_data(inner); curr_type = &(*curr_type)->right) {
string type_name = slurp_until(inner, ':');
// End insert_container Special Uses(type_name)
if (!contains_key(Type_ordinal, type_name)
// types can contain integers, like for array sizes
&& !is_integer(type_name)) {
put(Type_ordinal, type_name, Next_type_ordinal++);
}
*curr_type = new type_tree(get(Type_ordinal, type_name));
trace(9993, "parse") << " type: " << get(Type_ordinal, type_name) << end();
}
info.elements.push_back(new_type);
}
assert(SIZE(info.elements) == SIZE(info.element_names));
info.size = SIZE(info.elements);
}
void skip_bracket(istream& in, string message) {
skip_whitespace_and_comments(in);
if (in.get() != '[')
raise_error << message << '\n' << end();
}
:(scenarios run)
:(scenario container_define_twice)
container foo [
x:number
]
container foo [
y:number
]
recipe main [
1:number <- copy 34
2:number <- copy 35
3:number <- get 1:foo, 0:offset
4:number <- get 1:foo, 1:offset
]
+mem: storing 34 in location 3
+mem: storing 35 in location 4
//: ensure types created in one scenario don't leak outside it.
:(before "End Globals")
vector<type_ordinal> Recently_added_types;
:(before "End load_permanently") //: for non-tests
Recently_added_types.clear();
:(before "End Setup") //: for tests
for (long long int i = 0; i < SIZE(Recently_added_types); ++i) {
if (!contains_key(Type, Recently_added_types.at(i))) continue;
Type_ordinal.erase(get(Type, Recently_added_types.at(i)).name);
// todo: why do I explicitly need to provide this?
for (long long int j = 0; j < SIZE(Type.at(Recently_added_types.at(i)).elements); ++j) {
delete Type.at(Recently_added_types.at(i)).elements.at(j);
}
Type.erase(Recently_added_types.at(i));
}
Recently_added_types.clear();
// delete recent type references
// can't rely on Recently_added_types to cleanup Type_ordinal, because of deliberately misbehaving tests with references to undefined types
map<string, type_ordinal>::iterator p = Type_ordinal.begin();
while(p != Type_ordinal.end()) {
// save current item
string name = p->first;
type_ordinal t = p->second;
// increment iterator
++p;
// now delete current item if necessary
if (t >= 1000) Type_ordinal.erase(name);
}
//: lastly, ensure scenarios are consistent by always starting them at the
//: same type number.
Next_type_ordinal = 1000;
:(before "End Test Run Initialization")
assert(Next_type_ordinal < 1000);
:(before "End Setup")
Next_type_ordinal = 1000;
//:: Allow container definitions anywhere in the codebase, but complain if you
//:: can't find a definition at the end.
:(scenario run_complains_on_unknown_types)
% Hide_errors = true;
recipe main [
# integer is not a type
1:integer <- copy 0
]
+error: main: unknown type integer in '1:integer <- copy 0'
:(scenario run_allows_type_definition_after_use)
% Hide_errors = true;
recipe main [
1:bar <- copy 0/unsafe
]
container bar [
x:number
]
$error: 0
:(after "Begin Instruction Modifying Transforms")
// Begin Type Modifying Transforms
Transform.push_back(check_or_set_invalid_types); // idempotent
// End Type Modifying Transforms
:(code)
void check_or_set_invalid_types(const recipe_ordinal r) {
for (long long int index = 0; index < SIZE(get(Recipe, r).steps); ++index) {
const instruction& inst = get(Recipe, r).steps.at(index);
for (long long int i = 0; i < SIZE(inst.ingredients); ++i) {
check_or_set_invalid_types(inst.ingredients.at(i).type, inst.ingredients.at(i).properties.at(0).second,
maybe(get(Recipe, r).name), "'"+inst.to_string()+"'");
}
for (long long int i = 0; i < SIZE(inst.products); ++i) {
check_or_set_invalid_types(inst.products.at(i).type, inst.products.at(i).properties.at(0).second,
maybe(get(Recipe, r).name), "'"+inst.to_string()+"'");
}
}
}
void check_or_set_invalid_types(type_tree* type, const string_tree* type_name, const string& block, const string& name) {
// can't assert that type_name is non-null, even at the top of a recursive call tree
if (!type) return; // will throw a more precise error elsewhere
// End Container Type Checks
if (type->value == 0) {
assert(!type->left && !type->right);
return;
}
if (!contains_key(Type, type->value)) {
if (type_name && contains_key(Type_ordinal, type_name->value))
type->value = get(Type_ordinal, type_name->value);
else if (type_name)
raise_error << block << "unknown type " << type_name->value << " in " << name << '\n' << end();
else
raise_error << block << "missing type in " << name << '\n' << end();
}
check_or_set_invalid_types(type->left, type_name ? type_name->left : NULL, block, name);
check_or_set_invalid_types(type->right, type_name ? type_name->right : NULL, block, name);
}
:(scenario container_unknown_field)
% Hide_errors = true;
container foo [
x:number
y:bar
]
+error: foo: unknown type in y
:(scenario read_container_with_bracket_in_comment)
container foo [
x:number
# ']' in comment
y:number
]
+parse: --- defining container foo
+parse: element name: x
+parse: type: 1
+parse: element name: y
+parse: type: 1
:(before "End Transform All")
check_container_field_types();
:(code)
void check_container_field_types() {
for (map<type_ordinal, type_info>::iterator p = Type.begin(); p != Type.end(); ++p) {
const type_info& info = p->second;
// Check Container Field Types(info)
for (long long int i = 0; i < SIZE(info.elements); ++i)
check_invalid_types(info.elements.at(i), maybe(info.name), info.element_names.at(i));
}
}
void check_invalid_types(const recipe_ordinal r) {
for (long long int index = 0; index < SIZE(get(Recipe, r).steps); ++index) {
const instruction& inst = get(Recipe, r).steps.at(index);
for (long long int i = 0; i < SIZE(inst.ingredients); ++i) {
check_invalid_types(inst.ingredients.at(i).type,
maybe(get(Recipe, r).name), "'"+inst.to_string()+"'");
}
for (long long int i = 0; i < SIZE(inst.products); ++i) {
check_invalid_types(inst.products.at(i).type,
maybe(get(Recipe, r).name), "'"+inst.to_string()+"'");
}
}
}
void check_invalid_types(type_tree* type, const string& block, const string& name) {
if (!type) return; // will throw a more precise error elsewhere
// End Container Type Checks
if (type->value == 0) {
assert(!type->left && !type->right);
return;
}
if (!contains_key(Type, type->value))
raise_error << block << "unknown type in " << name << '\n' << end();
check_invalid_types(type->left, block, name);
check_invalid_types(type->right, block, name);
}
//:: Construct types out of their constituent fields. Doesn't currently do
//:: type-checking but *does* match sizes.
:(before "End Primitive Recipe Declarations")
MERGE,
:(before "End Primitive Recipe Numbers")
put(Recipe_ordinal, "merge", MERGE);
:(before "End Primitive Recipe Checks")
case MERGE: {
break;
}
:(before "End Primitive Recipe Implementations")
case MERGE: {
products.resize(1);
for (long long int i = 0; i < SIZE(ingredients); ++i)
for (long long int j = 0; j < SIZE(ingredients.at(i)); ++j)
products.at(0).push_back(ingredients.at(i).at(j));
break;
}
:(scenario merge)
container foo [
x:number
y:number
]
recipe main [
1:foo <- merge 3, 4
]
+mem: storing 3 in location 1
+mem: storing 4 in location 2
|