This provides the ivl_target.h interface for class definitions
and expressions, the vvp code generator support for class objects
and properties, and the vvp run time support. Trivial class objects
now seem to work.
Create stub class objects at the vvp level and generate the code
to invoke that stub. Implement the routines needed to implement
a test for null object references.
This will hopefully improve performance slightly, but also this
intended as a model for what to do when I get around to doing the
same thing to other data types.
Strings, when put into dynamic arrays, are treated as first class
types much line reals. Add the code generator and vvp support for
this situation. Also fix a bug distinguishing between character
selects from strings and select form arrays of strings.
This involves working out the code to get the base type of a select
expression of a darray. Also added the runtime support for darrays
with real value elements.
When sending a string to a system task/function allocate the space needed
to avoid truncating the string vs using a large fixed buffer.
In vvp allocate and use an exactly sized buffer for the MCD print routine if
the fixed buffer is not large enough. Using a fixed buffer keeps normal
printing fast.
To implement the $countdrivers system function, we need to be able to
find all the driver values for a given wire. Currently, if a wire has
has more than four drivers, the compiler builds a resolver tree out
of 4-input nodes to resolve the driven values, and there is no way at
run time to work back from the output node to the original driver
values. This patch moves the implementation of the resolver tree into
a single vvp functor (using a mechanism similar to wide functors to
support more than 4 inputs), thus gathering all the driver values into
a single place.
Implement through the ivl core to the ivl_target.h API.
Also draft implementation of creating and storing arrays
in the vvp runtime and code generator.
When string[x] is an l-value, generate code to implement something
like the string.putc(x, ...) method.
Also handle when string[x] is the argument of a system task. In that
case resort to treating it as a calculated 8-bit vector, because that
is what it is.
This also advances support for string expressions in general.
Handle assignments to string variables in the code generator by
trying to calculate a string expression. This involves the new
string object thread details.
In vvp, create the .var/str variable for representing strings, and
handle strings in the $display system task.
Add to vvp threads the concept of a stack of strings. This is going to
be how complex objects are to me handled in the future: forth-like
operation stacks. Also add the first two instructions to minimally get
strings to work.
In the parser, handle the variable declaration and make it available
to the ivl_target.h code generator. The vvp code generator can use this
information to generate the code for new vvp support.
Added: basic vpiPort VPI Objects for vpiModulkes
vpiDirection, vpiPortIndex, vpiName, vpiSize attributes
Since ports do not exist as net-like entities (nets either side
module instance boundaries are in effect connect directly in
the language front-ends internal representation) the port information
is effectively just meta-data passed through t-dll interface and
output as a additional annotation of module scopes in vvp.
Added: vpiLocalParam attribute for vpiParameter VPI objects
Added: support build for 32-bit target on 64-bit host (--with-m32
option to configure.in and minor tweaks to Makefiles and systemc-vpi).
The IEEE standard does not specify the behaviour of a tranif primitive
when its control input is an 'x' or 'z'. vvp currently treats these as
if the tran was turned off, but it would be better to propagate the
uncertainty to the tran bi-directional ports. For compatibility with
other simulators, we adopt the behaviour specified for MOS primitives.
If a tranif gate has a delay, the vvp code generator needs to generate
a unique label for the island port used for the tranif enable, to
prevent a name collision if the undelayed signal is also connected
to the island.
Also add an assertion in vvp to catch bugs like this.
This is a pretty trivial fix for the code generation of compressed
assign to a memory word. We generated incorect code for the stash
of the calculated word index, causing the assign of the result to
not work properly.
Now we have a code generator that can handle compressed assignments
as they have been re-imagined in elaboration. There are some cases
that are not yet supported, we'll patch them up in due course.
If a wired and/or net has more than four connections all the other
resolution branches must also be wired and/or. All other nets can
just be tri since tri0/tri1 only needs the final resolution to be
an active pull up/down.
Since synthesis is not currently supported we do not support/generate
sync/async set or clear control inputs. This is further complicated by
the fact that the VVP DFF primitive is not fully implemented.
Both UDPs and system functions use the wide input functor. This patch
modified the code generator to create a local net declaration for the
output net if we have either a delay or modpath connecting the output
to the true output. This is needed so that the wide input can be
cleaned up correctly.
Local real nets were also added to the local net pool when testing with
valgrind. This allows them to be cleaned up at the end.
This patch adds error messages that forcing a word to/from a variable
array is not currently supported. This is because variable arrays no
longer are fully populated and don't have an access functor for each
word. Forcing a word from/to a net array does work as expected since
each word in a net array is created.
Technically forcing a variable array word is not supported in 1364-2005.
Reading from an array word, which is supported, will be fixed in
development once the expression rework is finished.
The error message printed when forcing a bit/part select l-value was
also improved.
Stephen Williams
Cary R
Arun Persaud
Martin Whitaker
Andrew Stevens
Martin Whitaker