def public_context_predicate() -> Expr:
return And(
GreaterEqual(Call(const.TYPES_TO_INDEX, [Variable("First")]), Variable("Buffer_First")),
LessEqual(Call(const.TYPES_TO_INDEX, [Variable("Last")]), Variable("Buffer_Last")),
Less(Variable("Buffer_Last"), Last(const.TYPES_INDEX)),
LessEqual(Variable("First"), Add(Variable("Last"), Number(1))),
Less(Variable("Last"), Last(const.TYPES_BIT_INDEX)),
Equal(Rem(Variable("First"), Size(const.TYPES_BYTE)), Number(1)),
Equal(Rem(Variable("Last"), Size(const.TYPES_BYTE)), Number(0)),
)
def _create_ptr_subtypes(self,
slots: Sequence[NumberedSlotInfo]) -> UnitPart:
unit = UnitPart(specification=[
Subtype(
self._ptr_type(size),
const.TYPES_BYTES_PTR,
aspects=[
DynamicPredicate(
OrElse(
Equal(Variable(self._ptr_type(size)),
Variable("null")),
AndThen(
Equal(First(self._ptr_type(size)),
First(const.TYPES_INDEX)),
Equal(
Last(self._ptr_type(size)),
Add(First(const.TYPES_INDEX),
Number(size - 1)),
),
),
))
],
) for size in sorted({slot.size
for slot in slots})
])
self._declaration_context.append(
WithClause(self._prefix * const.TYPES_PACKAGE))
self._declaration_context.append(
UseTypeClause(self._prefix * const.TYPES_INDEX))
self._declaration_context.append(
UseTypeClause(self._prefix * const.TYPES_BYTES_PTR))
return unit
def create_present_function() -> UnitPart:
specification = FunctionSpecification(
"Present", "Boolean",
[Parameter(["Ctx"], "Context"),
Parameter(["Fld"], "Field")])
return UnitPart(
[SubprogramDeclaration(specification)],
private=[
ExpressionFunctionDeclaration(
specification,
AndThen(
Call("Structural_Valid", [
Indexed(Variable("Ctx.Cursors"), Variable("Fld"))
]),
Less(
Selected(
Indexed(Variable("Ctx.Cursors"),
Variable("Fld")), "First"),
Add(
Selected(
Indexed(Variable("Ctx.Cursors"),
Variable("Fld")), "Last"),
Number(1),
),
),
),
)
],
)
def field_condition_call(
prefix: str,
message: model.Message,
field: model.Field,
value: Expr = None,
aggregate: Expr = None,
size: Expr = None,
) -> Expr:
package = prefix * message.identifier
if value is None:
value = Number(0)
if aggregate is None:
aggregate = EMPTY_ARRAY
if size is None:
size = Call(
package * "Field_Size",
[Variable("Ctx"), Variable(package * field.affixed_name)],
)
return Call(
package * "Field_Condition",
[
Variable("Ctx"),
Variable(package * field.affixed_name),
*([value] if has_value_dependent_condition(message) else []),
*([aggregate] if has_aggregate_dependent_condition(message) else []),
*([size] if has_size_dependent_condition(message, field) else []),
],
)
def _create_memory(slots: Sequence[NumberedSlotInfo]) -> UnitPart:
return UnitPart([
RecordType(
"Memory",
[
Component(
f"Slot_{slot.slot_id}",
Slice(
Variable(const.TYPES_BYTES),
First(const.TYPES_INDEX),
Add(First(const.TYPES_INDEX),
Number(slot.size - 1)),
),
NamedAggregate(("others", Number(0))),
aliased=True,
) for slot in slots
],
)
])
def byte_aligned_field(prefix: str, message: model.Message, field: model.Field) -> Expr:
return Equal(
Rem(
Call(
prefix * message.identifier * "Field_First",
[
Variable("Ctx"),
Variable(prefix * message.identifier * field.affixed_name),
],
),
Size(const.TYPES_BYTE),
),
Number(1),
)
def cursors_invariant() -> Expr:
return ForAllIn(
"F",
Variable("Field"),
If(
[
(
Call(
"Structural_Valid",
[Indexed(Variable("Cursors"), Variable("F"))],
),
And(
GreaterEqual(
Selected(Indexed(Variable("Cursors"), Variable("F")), "First"),
Variable("First"),
),
LessEqual(
Selected(Indexed(Variable("Cursors"), Variable("F")), "Last"),
Variable("Verified_Last"),
),
LessEqual(
Selected(Indexed(Variable("Cursors"), Variable("F")), "First"),
Add(
Selected(
Indexed(Variable("Cursors"), Variable("F")),
"Last",
),
Number(1),
),
),
Call(
"Valid_Value",
[
Variable("F"),
Selected(
Indexed(Variable("Cursors"), Variable("F")),
"Value",
),
],
),
),
)
]
),
)
def create_verify_procedure(
self,
message: Message,
scalar_fields: Mapping[Field, Scalar],
composite_fields: Sequence[Field],
) -> UnitPart:
specification = ProcedureSpecification(
"Verify",
[InOutParameter(["Ctx"], "Context"),
Parameter(["Fld"], "Field")])
valid_field_condition = AndThen(
Call(
"Valid_Value",
[Variable("Fld"), Variable("Value")],
),
Call(
"Field_Condition",
[
Variable("Ctx"),
Variable("Fld"),
*([Variable("Value")] if
common.has_value_dependent_condition(message) else []),
*([
Slice(
Variable("Ctx.Buffer.all"),
Call(
const.TYPES_TO_INDEX,
[
Call("Field_First",
[Variable("Ctx"),
Variable("Fld")])
],
),
Call(
const.TYPES_TO_INDEX,
[
Call("Field_Last",
[Variable("Ctx"),
Variable("Fld")])
],
),
)
] if common.has_aggregate_dependent_condition(message) else
[]),
*([Call("Field_Size",
[Variable("Ctx"), Variable("Fld")])]
if common.has_size_dependent_condition(message) else []),
],
),
)
last = Mul(
Div(
Add(
Call("Field_Last",
[Variable("Ctx"), Variable("Fld")]),
Size(const.TYPES_BYTE),
-Number(1),
),
Size(const.TYPES_BYTE),
),
Size(const.TYPES_BYTE),
)
set_cursors_statements = [
*([
PragmaStatement(
"Assert",
[
If([(
Or(*[
Equal(Variable("Fld"), Variable(
f.affixed_name))
for f in message.direct_predecessors(FINAL)
]),
Equal(
Mod(
Call("Field_Last",
[Variable("Ctx"),
Variable("Fld")]),
Size(const.TYPES_BYTE),
),
Number(0),
),
)])
],
)
] if len(message.fields) > 1 else []),
# Improve provability of context predicate
PragmaStatement(
"Assert",
[Equal(Mod(last, Size(const.TYPES_BYTE)), Number(0))]),
Assignment(Variable("Ctx.Verified_Last"), last),
PragmaStatement(
"Assert",
[
LessEqual(
Call("Field_Last", [Variable("Ctx"),
Variable("Fld")]),
Variable("Ctx.Verified_Last"),
)
],
),
IfStatement(
[(
Call("Composite_Field", [Variable("Fld")]),
[set_context_cursor_composite_field("Fld")],
)],
[set_context_cursor_scalar()],
) if scalar_fields and composite_fields else
set_context_cursor_scalar()
if scalar_fields and not composite_fields else
set_context_cursor_composite_field("Fld"),
*([
# https://github.com/Componolit/RecordFlux/issues/664
# The provability of the context predicate is increased by splitting the
# assignment into multiple statements.
Assignment(
Indexed(
Variable("Ctx.Cursors"),
Call(
"Successor",
[Variable("Ctx"), Variable("Fld")],
),
),
NamedAggregate(
("State", Variable("S_Invalid")),
("Predecessor", Variable("Fld")),
),
)
] if len(message.fields) > 1 else []),
]
return UnitPart(
[
SubprogramDeclaration(
specification,
[
Precondition(
Call(
self.prefix * message.identifier *
"Has_Buffer",
[Variable("Ctx")],
)),
Postcondition(
And(
Call("Has_Buffer", [Variable("Ctx")]),
*common.context_invariant(message),
)),
],
)
],
[
SubprogramBody(
specification,
[ObjectDeclaration(["Value"], const.TYPES_BASE_INT)],
[
IfStatement([(
AndThen(
Call(
"Invalid",
[
Indexed(Variable("Ctx.Cursors"),
Variable("Fld"))
],
),
Call("Valid_Predecessor",
[Variable("Ctx"),
Variable("Fld")]),
Call("Path_Condition",
[Variable("Ctx"),
Variable("Fld")]),
),
[
IfStatement(
[(
Call(
"Sufficient_Buffer_Length",
[Variable("Ctx"),
Variable("Fld")],
),
[
Assignment(
"Value",
If(
[(
Call(
"Composite_Field",
[
Variable(
"Fld"),
],
),
Number(0),
)],
Call(
"Get",
[
Variable("Ctx"),
Variable("Fld"),
],
),
) if scalar_fields
and composite_fields else Call(
"Get",
[
Variable("Ctx"),
Variable("Fld"),
],
) if scalar_fields else
Number(0),
),
IfStatement(
[(
valid_field_condition,
set_cursors_statements,
)],
[
Assignment(
Indexed(
Variable(
"Ctx.Cursors"),
Variable("Fld"),
),
NamedAggregate(
(
"State",
Variable(
"S_Invalid"
),
),
(
"Predecessor",
Variable(
FINAL.
affixed_name,
),
),
),
)
],
),
],
)],
[
Assignment(
Indexed(Variable("Ctx.Cursors"),
Variable("Fld")),
NamedAggregate(
("State",
Variable("S_Incomplete")),
(
"Predecessor",
Variable(
FINAL.affixed_name),
),
),
)
],
)
],
)], )
],
)
],
)
def initialize_field_statements(
field: model.Field, reset_written_last: bool = False
) -> Sequence[Statement]:
return [
CallStatement(
"Reset_Dependent_Fields",
[Variable("Ctx"), Variable(field.affixed_name)],
),
# https://github.com/Componolit/RecordFlux/issues/868
PragmaStatement(
"Warnings",
[
Variable("Off"),
String("attribute Update is an obsolescent feature"),
],
),
Assignment(
"Ctx",
Update(
"Ctx",
("Verified_Last", Variable("Last")),
(
"Written_Last",
Variable("Last")
if reset_written_last
else Max(
const.TYPES_BIT_LENGTH,
Variable("Ctx.Written_Last"),
Variable("Last"),
),
),
),
),
PragmaStatement(
"Warnings",
[
Variable("On"),
String("attribute Update is an obsolescent feature"),
],
),
Assignment(
Indexed(Variable("Ctx.Cursors"), Variable(field.affixed_name)),
NamedAggregate(
("State", Variable("S_Structural_Valid")),
("First", Variable("First")),
("Last", Variable("Last")),
("Value", Number(0)),
(
"Predecessor",
Selected(
Indexed(
Variable("Ctx.Cursors"),
Variable(field.affixed_name),
),
"Predecessor",
),
),
),
),
Assignment(
Indexed(
Variable("Ctx.Cursors"),
Call(
"Successor",
[Variable("Ctx"), Variable(field.affixed_name)],
),
),
NamedAggregate(
("State", Variable("S_Invalid")),
("Predecessor", Variable(field.affixed_name)),
),
),
]
def context_predicate(
message: model.Message, composite_fields: Sequence[model.Field], prefix: str
) -> Expr:
def cursors_invariant() -> Expr:
return ForAllIn(
"F",
Variable("Field"),
If(
[
(
Call(
"Structural_Valid",
[Indexed(Variable("Cursors"), Variable("F"))],
),
And(
GreaterEqual(
Selected(Indexed(Variable("Cursors"), Variable("F")), "First"),
Variable("First"),
),
LessEqual(
Selected(Indexed(Variable("Cursors"), Variable("F")), "Last"),
Variable("Verified_Last"),
),
LessEqual(
Selected(Indexed(Variable("Cursors"), Variable("F")), "First"),
Add(
Selected(
Indexed(Variable("Cursors"), Variable("F")),
"Last",
),
Number(1),
),
),
Call(
"Valid_Value",
[
Variable("F"),
Selected(
Indexed(Variable("Cursors"), Variable("F")),
"Value",
),
],
),
),
)
]
),
)
def valid_predecessors_invariant() -> Expr:
return AndThen(
*[
If(
[
(
Call(
"Structural_Valid",
[
Indexed(
Variable("Cursors"),
Variable(f.affixed_name),
)
],
),
Or(
*[
expr.AndThen(
expr.Call(
"Structural_Valid"
if l.source in composite_fields
else "Valid",
[
expr.Indexed(
expr.Variable("Cursors"),
expr.Variable(l.source.affixed_name),
)
],
),
expr.Equal(
expr.Selected(
expr.Indexed(
expr.Variable("Cursors"),
expr.Variable(f.affixed_name),
),
"Predecessor",
),
expr.Variable(l.source.affixed_name),
),
l.condition.substituted(
substitution(message, embedded=True, prefix=prefix)
),
)
.simplified()
.ada_expr()
for l in message.incoming(f)
]
),
)
]
)
for f in message.fields
if f not in message.direct_successors(model.INITIAL)
]
)
def invalid_successors_invariant() -> Expr:
return AndThen(
*[
If(
[
(
AndThen(
*[
Call(
"Invalid",
[
Indexed(
Variable("Cursors"),
Variable(p.affixed_name),
)
],
)
for p in message.direct_predecessors(f)
]
),
Call(
"Invalid",
[
Indexed(
Variable("Cursors"),
Variable(f.affixed_name),
)
],
),
)
]
)
for f in message.fields
if f not in message.direct_successors(model.INITIAL)
]
)
return AndThen(
If(
[
(
NotEqual(Variable("Buffer"), Variable("null")),
And(
Equal(First("Buffer"), Variable("Buffer_First")),
Equal(Last("Buffer"), Variable("Buffer_Last")),
),
)
]
),
public_context_predicate(),
LessEqual(Sub(Variable("First"), Number(1)), Variable("Verified_Last")),
LessEqual(Sub(Variable("First"), Number(1)), Variable("Written_Last")),
LessEqual(Variable("Verified_Last"), Variable("Written_Last")),
LessEqual(Variable("Written_Last"), Variable("Last")),
Equal(Rem(Variable("First"), Size(const.TYPES_BYTE)), Number(1)),
Equal(Rem(Variable("Last"), Size(const.TYPES_BYTE)), Number(0)),
Equal(Rem(Variable("Verified_Last"), Size(const.TYPES_BYTE)), Number(0)),
Equal(Rem(Variable("Written_Last"), Size(const.TYPES_BYTE)), Number(0)),
cursors_invariant(),
valid_predecessors_invariant(),
invalid_successors_invariant(),
message_structure_invariant(message, prefix, embedded=True),
)
def message_structure_invariant(
message: model.Message, prefix: str, link: model.Link = None, embedded: bool = False
) -> Expr:
def prefixed(name: str) -> expr.Expr:
return expr.Selected(expr.Variable("Ctx"), name) if not embedded else expr.Variable(name)
if not link:
return message_structure_invariant(
message, prefix, message.outgoing(model.INITIAL)[0], embedded
)
source = link.source
target = link.target
if target == model.FINAL:
return TRUE
field_type = message.types[target]
condition = link.condition.substituted(substitution(message, prefix, embedded)).simplified()
size = (
field_type.size
if isinstance(field_type, model.Scalar)
else link.size.substituted(
substitution(message, prefix, embedded, target_type=const.TYPES_BIT_LENGTH)
).simplified()
)
first = (
prefixed("First")
if source == model.INITIAL
else link.first.substituted(
substitution(message, prefix, embedded, target_type=const.TYPES_BIT_INDEX)
)
.substituted(
mapping={
expr.UNDEFINED: expr.Add(
expr.Selected(
expr.Indexed(prefixed("Cursors"), expr.Variable(source.affixed_name)),
"Last",
),
expr.Number(1),
)
}
)
.simplified()
)
invariant = [
message_structure_invariant(message, prefix, l, embedded) for l in message.outgoing(target)
]
return If(
[
(
AndThen(
Call(
"Structural_Valid",
[Indexed(prefixed("Cursors").ada_expr(), Variable(target.affixed_name))],
),
*([condition.ada_expr()] if condition != expr.TRUE else []),
),
AndThen(
Equal(
Add(
Sub(
Selected(
Indexed(
prefixed("Cursors").ada_expr(),
Variable(target.affixed_name),
),
"Last",
),
Selected(
Indexed(
prefixed("Cursors").ada_expr(),
Variable(target.affixed_name),
),
"First",
),
),
Number(1),
),
size.ada_expr(),
),
Equal(
Selected(
Indexed(
prefixed("Cursors").ada_expr(),
Variable(target.affixed_name),
),
"Predecessor",
),
Variable(source.affixed_name),
),
Equal(
Selected(
Indexed(
prefixed("Cursors").ada_expr(),
Variable(target.affixed_name),
),
"First",
),
first.ada_expr(),
),
*[i for i in invariant if i != TRUE],
),
)
]
)
Selected,
Size,
Statement,
String,
Sub,
Update,
ValueRange,
Variable,
WithClause,
)
from rflx.const import BUILTINS_PACKAGE
from rflx.identifier import ID
from . import const
EMPTY_ARRAY = NamedAggregate((ValueRange(Number(1), Number(0)), Number(0)))
class Debug(enum.Enum):
NONE = enum.auto()
BUILTIN = enum.auto()
EXTERNAL = enum.auto()
def substitution(
message: model.Message,
prefix: str,
embedded: bool = False,
public: bool = False,
target_type: Optional[ID] = const.TYPES_BASE_INT,
) -> Callable[[expr.Expr], expr.Expr]: