In addition to providing positional arguments for task and functions
SystemVerilog allows to bind arguments by name. This is similar to how
module ports can be bound by name.
```
task t(int a, int b); ... endtask
...
t(.b(1), .a(2));
```
Extend the parser and elaboration stage to be able to handle this. During
elaboration the named argument list is transformed into a purely positional
list so that later stages like synthesis do not have to care about the
names.
For system functions and tasks all arguments must be unnamed, otherwise an
error will be reported.
In addition to functions and tasks arguments can also be bound by name for
the various different ways of invoking a class constructor.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
There are a few places in the code where a std::list is copied to a
std::vector by iterating through the list and copying each element over to
the vector. The std::vector type has a iterator based constructor that can
do the same.
Update the code to use it instead. This removes a bit of boilerplate code
and also makes it easier to update the code.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
SystemVerilog allows to declare const variables. These variables are
read-only and can not be assigned a value after their declaration. It is
only possible to assign an initial value as an initializer.
E.g.
```
const int x = 10;
x = 20; // Error
```
The LRM requires that for variable declarations with static storage the
initializer is a constant expression with the extension that other const
variables are also allowed. const variables with automatic storage can
be initialized by any expression.
Checking if an expression contains only const variables requires a bit more
work to implement. So for now be more lenient that what the standard
requires and allow arbitrary expressions to initialize const variables even
for those with static storage.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
`ivl_assert()` is similar to `assert()` except that it will also include
source file and line information about the expression for which the assert
was triggered.
Use `ivl_assert()` instead of `assert()` where the line information is
available. This will generate better bug reports and make it easier to
diagnose why an assert is triggered.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
In SystemVerilog identifiers can usually have an additional package scope
in which they should be resolved. At the moment there are many places in
the code base that handle the resolution of the package scope.
Add a common data type for package scoped paths as well as a
symbol_search() variant that works on package scoped identifiers. This
allows to handle package scope resolution in a central place.
Having the code in a central place makes it easier to ensure consistent and
correct behavior. E.g. there are currently some corner case bugs that are
common to all implementations. With the common implementation it only has
to be fixed in one place.
It will also make it easier to eventually implement class scoped
identifiers.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The custom `svector` class is essentially a subset of `std::vector`. There
is no inherent advantage to using `svector`. Both have the same memory
footprint.
`svector` was designed to be of static size, but there are a few places in
the parser where it has to grow at runtime. Handling this becomes a bit
easier by switching to `std::vector` since it is possible to use its
methods which take care of resizing the vector.
This also allows to remove the unused parameter of the `lgate` struct
constructor, which was only needed for compatibility with `svector`.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
The unique, unique0, and priority keywords can decorate case statements
to tell the run time (or synthesis) to do extra tests (or make extra
assumptions). These tests are not implemented in the vvp run time, but
now the decorations make it to the code generators.
If a static variable declared in a task, function, or block has an
initialisation expression, SystemVerilog requires the declaration to
have an explicit static lifetime. This is supposed to be a compile
error, but for now just output a warning.
Implementing this required adding support in the parser for explicit
lifetimes in variable declarations. For now, just output an error if
the user asks for a lifetime that isn't the default for that scope.
Class types that have both implicit construction and
an explicit constructor can blend the implicit and
explicit construction into the "new" function defined
by the user. This doesn't change the behavior any, but
removes a function call and related scope.
I'm adding more uses of the make_range_from_width function, so
it seems like time to get rid of its use of the svector template.
This thread led to a lot of other uses of svector that had to
also be removed.
This patch adds a number of compile and run-time checks for illegal
uses of variables declared in automatic tasks and functions. It
also adds a check for event expressions in automatic tasks that use
features not yet supported in VVP.
Continue cleaning up shadowed variables, flagged by turning on -Wshadow.
No intended change in functionality. Patch looks right, and is tested
to compile and run on my machine. No regressions in test suite.
This patch removes all the checks for constant expressions performed
during the parsing phase, as these checks are (mostly) repeated during
elaboration. It adds the missing check in the elaboration phase (the
RHS of a register initialisation), and improves the error reporting
and error recovery in other checks.
This patch fixes pr2132552, which was caused by a fault in the parser
constant expression checking.
This patch adds blocking repeat event controls and also makes the
base repeat statement sign aware. If the argument to repeat is
negative (it must be a signed variable) then this is treated just
like an argument of 0 (there is no looping). Doing this allows us
to model the repeat event control as follows.
lhs = repeat(count) @(event) rhs;
is translated to:
begin
temp = rhs;
repeat (count) @(event);
lhs = temp;
end
This patch also pushes the non-blocking event control
information to the elaboration phase where it will report they
are not currently supported.
Named begin/end blocks burried within generate schemes need to be
elaborated. Handle this by remembering to elaborate_scope on the
statements within the generate scheme.
In the process, clean up/regularize some of the member names and
methods.
All the pform objects that represent lexical scope now are derived
from the PScope class, and are kept in a lexical_scope table so that
the scope can be managed.
objects in the pform,
Handle named events within the mix of net events
and edges. As a unified lot they get caught together.
wait statements are broken into more complex statements
that include a conditional.
Do not generate NetPEvent or NetNEvent objects in
elaboration. NetEvent, NetEvWait and NetEvProbe
take over those functions in the netlist.
Martin Whitaker
Lars-Peter Clausen
Cary R
Stephen Williams
Arun Persaud
Martin Whitaker
Larry Doolittle
steve