In the rare cases where DARRAY signals are in the network, handle
them by creating the proper ivl_nexus_t node. This also implements
the receive of vvp_object_t objects bu vvp_fun_anyedge_sa. This
together makes it possible for IVL_VT_DQUEUE objects to be in
wait lists.
This fixes#412
A NetESelect is used for accessing packed struct members and also for
accessing dynamic array elements. In these cases the expr_type() and
enumeration() methods should reflect the member/element type.
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.
If the condition expression is 2-state, the result won't be blended, so
the result will be a valid enum value if both true and false expressions
return the same enum type.
The fix for the compiler hang when calculating the sensitivity list
for an always_comb construct containing recursive function calls
could cause the compiler to ignore sequential calls to the same
function, and thus not add the arguments of those calls to the
sensitivity list.
We don't support evaluating user-defined system functions at compile
time. If possible, defer evaluation until run time. If used in a
constant expression, output a "sorry" message.
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.
The compilation unit scope is now treated as a specialised form of
package (with an automatically generated name). All items declared
outside a design element are added to the current compilation unit
package. Apart from when searching for a symbol, once we get into
elaboration we can treat these just like any other package.
A compressed assignment statement should give exactly the same
result as the equivalent uncompressed statement. This means
that the type (signed/unsigned) of the LHS affects the type of
the RHS expression (unlike in normal assignments). We need to
take care that bit/part selects and concatenations are correctly
identified as unsigned values, even in the cases where they
reduce to a single whole signal.
Synthesis could only handle relatively simple conditional constructs.
This rework aims to make it handle anything the user can throw at it
(or output a sensible message as to why it can't).
Changes so "Microsoft Visual Studio Express 2015 RC Web" could build it without a bunch of runtime errors and crashes during regression testing. When declaring an bitfield variable of type enum in a struct, the enum has to have an underlying integer type for MSVC++ when compiling a C++ file, and for these cases, it had to be unsigned integer for everything to work okay during regression testing.
When unsized literals are used in case item expressions, it is likely
that the calculated expression width will be larger than necessary to
unambiguously select the correct case item (particularly when using
"strict" expression elaboration). This patch adds an optimisation
step that prunes the expressions to the minimum necessary width.
This patch fixes the following enumeration bugs:
When looking for an enumeration look in the current scope and then
recursively in any parent scope.
Add enumeration definitions to a package scope.
Internally, treat the "$" as a special expression type that takes
as an argument the signal that is being indexed. In the vvp target,
use the $last system function to implement this.
Like this:
... if (ce0) foo <= foo_in;
... if (ce1) bar <= bar_in;
Note that this is within a block, and represents multiple FF nodes
with different clock enables.
When for example assigning to foo[<x>] within a contitional, and
doing synthesis, we need to create a NetSubstitute device to manage
the l-value bit selects.
This generates an EQZ LPM device that carries the case-z-ness to
the code generator.
Also add to the vvp code generator support for the EQZ device so
that the synthesis results can be simulated.
Account for the wildcard devices in the sizer.
When conditional ports are blending (by allowing NetPartSelects be
connected together to the outputs) make sure there isn't an accidental
overlap of drivers that invalidates the process.
In a design, there may be lingering NexusSet objects, or the
nodangle may itself use NexusSet objects. This creates links,
and this should not confuse the functor.
While we are at it, clean up some handling of events structures.
This required keeping for-loops as actual things through the
netlist form so that the synthesizer can get at and understand
the parts of the for-loop. This may improve vvp code generation
in the future, but for now continue to present to the vvp code
generation the block-while form.
If statements within blocks can confuse the synthesizer when there
are outputs that are assigned ahead of the if statement. This patch
handles that case.
If the l-value is an unresolved wire, then elaboration can allow
the assignment as long as it is to bits that are not otherwise
driven. Handle this in some simple cases.
When a module is instantiated multiple times, the enum
types contained within would cause trouble. This fixes
that by elaborating in proper scope context.
This patchs adds support for the $dimensions() and $unpacked_dimensions()
array functions. Since the argument is only used to get the type information
these functions can always be evaluated at compile time.
For the following functions if the dimension argument is constant or omitted
and the first argument is not dynamic (a string or dynamic array) they will
return the specified information.
$left(), $right(), $high(), $low(), $increment() and $size()
Dynamic information and a variable second argument will be implement in a
future patch.
This allows for syntax like a.b.c where a is a class with member
b, which is a class with member c, and so on. The handling is mostly
for the support of compound objects like classes.
This gets nested l-values to (but just short of) the ivl_target API.
Now the elaborator can process nested l-values, but I haven't figured
out how to present that at the ivl_target.h API.