Verilog generate schemes support a special case where conditional
generate schemes that contain only a nested conditional generate
scheme do not create a new scope. Instead, it relies on the nested
generate scheme to generate the scope.
unary expressions that have problems should not assert in the
test_width method. Instead, let the error propagate back and be
handled during expression elaboration. This found a few places
where expression widths/types weren't probed before elaboration.
Named blocks create scopes, and generated named blocks' scopes can
have signals declared in them. So the elaborate_sig for the generate
scheme needs to call the elaborate_sig for the processes as well as
the obvious gates and tasks/functions.
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.
Get at least basic elaboration of analog processes and contribution
statements. Bring the statements and analog statements together and
net future elaboration work sort out which statements are valid in
a given context. This makes sense because there really is a lot of
syntactic overlap, and analog behavioral code is processed somewhat
sequentially.
Put together the infrastructure for elaborating analog statements,
including create the NetAnalogTop objects that hold analog statements
and are in turn held by the design.
While doing this, clean up the various unique initial/always enumerations
to use the ivl_process_type_t type.
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.
Currently, parameters and localparams declared in tasks, functions,
generate blocks, and named blocks are placed in the parent module
scope. Event declarations in these scopes are not permitted (a
syntax error is reported). This patch corrects this behaviour, so
that all the above declarations are accepted and are placed in the
scope in which they are declared.
Note that the IEEE standard does not permit parameter declarations
in generate blocks. This patch causes the parser to reject such
declarations.
Nothing to do with tab width! Eliminates useless
trailing spaces and tabs, and nearly all <space><tab>
pairings. No change to derived files (e.g., .vvp),
non-master files (e.g., lxt2_write.c) or the new tgt-vhdl
directory.
Low priority, simple entropy reduction. Please apply
unless it deletes some steganographic content you want
to keep.
The generate block is a placeholder for the generate items, and it
is the items themselves that can specify the name of the generate
block that is created.
This patch pushes the automatic property for both tasks and
functions to the code generators. The vvp back end does not
currently support this so it will error out during code
generation. The VHDL back end should be able to use this
property and tgt-stub prints the property. Having this will
also make it easier when we do adding this to the runtime.
When elaborating a parameter expression fails we need to set the
expression to 0 since it has already been partially allocated.
Doing this allows us to not evaluate the dummy expression later.
The list of defparams in the pform module definitions (in class Module)
should not be consumed when they are used. The module may be instantiated
moltiple times, so consuming the defparams during elaboration will cause
subsequent instantiations to not have the defparams. That's wrong.
We must run generate schemes after running defparams because the
defparams may define the results of the generate schemes. So put
the generate schemes for a module scope into elaborator work items.
The l-value of a defparam assignment is a hierarchical name that may
include array selects to select scopes from module arrays. Therefore
it makes no sense to store parsed defparams in a map. Instead, they
should go into an ordered list. This also maked more sense because later
defparams *may* have the same name as a previous defparam, and will
override the previous defparam. So replace the map of parsed defparams
with a list of parsed defparams.
Also, as soon as the defparam expression is elaborated, the list entry
is no longer needed, so delete it. Save memory.
It is possible for defparams to not find their target the first time
around, because the elaboration of the target scope is not yet done.
So retry the defparams once for each scope by putting it on a work
item in the elaborator_work_items list.
When we detect that a module instance is an array of instances, delay
the elaboration of the array until after the first defparam processing
is complete. This allows for defparam statements to control the
instantiation of module instance arrays.
Generating task/function definitions involves getting the functions
to put themselves into the generate scheme instead of the module,
and getting elaboration to elaborate those definitions in the
generate scheme.
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.
Parameter value ranges support the exclude of a point as well as
range, so add the syntax to support that case. Internally it is
handled as a degenerate range, but the parse and initial elaboration
need to know about it.
Add include statements (<cstdlib> for abort()) and a cast.
Necessary and sufficient for successful compilation with
gcc-4.3 (Debian 4.3.0-4) 4.3.1 20080501 (prerelease)
Before this, the types of parameters were always logic, only the
width and signed-ness could be controlled. A parameter may take
on implicit real values if the expression were real.
With this patch, the type for the parameter can be explicitly set
to logic or real. This also means that the parameter real valued
expressions need to be more crefully treated, possibly with casting
integral expressions to real values, or real expressions to integral
values.
The pform is now translated/elaborated into NetScope objects. All that
remains is to check the parameter values against the ranges. This is
to be done in the evaluate_parameters() method.
Handle parameter value ranges as far as the pform. The +-inf expressions
are not handled yet, nor is the single value exclude, but the other
cases are handled.
This patch adds file and line information for parameters and
local parameters. It also adds file/line stubs for signals in
the tgt-* files. It adds the pform code needed to eventually
do genvar checks and passing of genvar file/line information.
It verifies that a genvar does not have the same name as a
parameter/local parameter.
This patch adds code to push the file and line information
for scope objects (modules, functions, tasks, etc.) to the
runtime. For modules, this includes the definition fields.
This patch reworks much of the ternary code to short circuit when
possible and supports real values better. It adds a blend operator
for real values that returns 0.0 when the values differ and the value
when they match. This deviates slightly from the standard which
specifies that the value for reals is always 0.0 when the conditional
is 'bx. There are also a couple bug fixes.
These fixes have not been ported to continuous assignments yet.
Ternary operators used at compile time and in procedural assignments
should be complete (short circuit and support real values).
When a bit port of a module instance is connected to a vector
argument, the MSB module instance should be connected to the MSB
of the vector argument. This matters only in the rare case that
the %m is used. It also makes wave dumps come out right.
Normally processes are found in the lexical scope of a module, but
there are special cases where processes (other then task/function
definitions) are in other lexical scopes. The most likely case is
initilizations that are in the lexical scope where the assigned
variable is declared.
In the process, the behaviors list is kept in the base PScope class
instead of the Module or any other derived lexical scope class.
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.
Generate case is a complex generate scheme where the items are
sub-schemes of the case generate itself. The parser handles them
something like nested generate statements, but storing the case
guards as the test expression. Then the elaborator notes the
case scheme and reaches into the case item schemes inside to make
up tests, select the generate item, and elaborate.
Currently, if a localparam declaration does not include a type or
range, the RHS expression is cast to an unsigned value. This patch
changes this to make the localparam inherit the type of the RHS
expression, as is done for parameter declarations and is specified
by the Verilog-2001 standard.
Rework the handling of file names to use a perm_string heap to hold
the file names, instead of the custom file name heap in the lexor.
Also rename the get_line to get_fileline to reflect its real duties.
This latter chage touched a lot of files.
Nil parameter overrides can turn up in positional paramter override
lists, where items are intentionally skipped.
Signed-off-by: Stephen Williams <steve@icarus.com>
Stephen Williams
Cary R
Martin Whitaker
Larry Doolittle
Martin Whitaker
steve