When creating an enum type it must be added to the scope where it is
declared so it can later be elaborated and the enum and its names can be
referenced in expressions.
In addition the names of the enum must be added to the lexor scope so that
name collisions are detected and can be reported as errors.
This is done with pform_put_enum_type_in_scope() function.
At the moment the function is called from two different places
* When adding a typedef of a enum type
* When creating a signal of a enum type
In addition the enum_type_t is added to a class scope `enum_sets` when
declaring a enum property in a class. But this only makes sure that the
enum gets elaborated, its names are not added to the lexor scope.
This works fine for the most part, but breaks for a few corner cases.
E.g. it is possible to declare a enum type as part of the subtype of
another packed type such as structs or packed arrays. E.g.
```
struct packed {
enum {
A
} e;
} s;
```
This is not covered by either of the cases above and neither do the names
of the enum get added to the lexor scope, nor is the enum type elaborated.
Another corner case that is currently not working is declaring a class
property where the type is a typedef of a enum that is declared outside of
the class. In this case the enum is elaborated again inside the class
scope. E.g. the below is supposed to work, but fails with an already
declared symbol error.
```
typedef enum {
A
} e_t;
class C;
typedef enum {
A
} e1;
e_t e2;
endclass
```
In addition since for enums declared in classes they are only added to
`enum_sets`, but names are not added to the lexor scope, it is possible to
declare a different symbol in the class scope with the same name.
E.g. the following elaborates fine
```
class C;
enum {
A
} e;
typedef int A;
endclass
```
To fix this call pform_put_enum_type_in_scope() when the enum_type_t is
created in the parser. This makes sure that it is handled the same
regardless where the type is declared or used.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
When creating a signal of a packed array it is checked that the base-type
of the packed array is a packed type.
But this check is only done if the packed array itself is the type of the
signal. Placing the packed array in a struct or class will elaborate fine,
but then crash during simulation.
E.g.
```
typedef real myreal;
struct packed {
myreal [1:0] p;
} s;
```
Move the check from signal creation to type elaboration, so that it is not
possible to create a packed type with a non-packed base-type.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Specifying and enum with an invalid dimension range results in an assert or
segfault. E.g. `enum [$] E { ... }`.
Use the `evaluate_ranges()` function to elaborate the enum dimensions. This
functions has proper error checking and recovery built-in.
In addition verify that there is at most one packed dimension.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The IEEE standard specifies that the numbering of generate blocks
restarts at 1 in each new scope, and that the 'else' part of an 'if'
construct is part of the same constuct, so has the same number.
This eliminates some indeterminism in the error messages, which was
causing occasional failures in CI. We don't expect this list to be
very large, so the O(n) insertion time should not be a problem.
Use the common data_type_or_implicit rules to support type
definitions for parameters. This eliminates a bunch of special
rules in parse.y, and opens the door for parameters having
more complex types.
The compiler elaborates types on the fly as they are used. For user-
defined types (typedefs) we must do the elaboration in the scope where
the type was declared, not in the scope where it is used.
Explicit imports should always conflict with local declarations using
the same name. Wildcard imports only conflict if they are referenced
before a local declaration with the same name.
This also unifies the detection of identifier conflicts.
This fixes the problem reported in GitHub issue #254, where if the
parser aborted on one compilation unit, spurious errors were reported
for the next compilation unit.
Lars-Peter Clausen
Stephen Williams
Martin Whitaker
Cary R
Stefan Biereigel