the PGAssign elaborate method used the test_width to get the width
of the r-value expression. This should be completely sufficient to
get the width of the expression, so always use a defined width to
elaborate the expression.
When ternary expressions are self-determined, use the test_width
method to get a proper reading of the expression width. Also improve
the test_width method to handle unsized operands.
This patch adds non-blocking event control for array words.
It also fixes a problem where the word used to put the
calculated delay for a non-blocking array assignment was
not being released. It also fixes the non-blocking array
assignments to correctly handle off the end/beginning part
selects.
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.
Since some event control assignments can be skipped we need an
event control clear so that future %evctl statements do not fail
their assert. This patch adds %evctl/c and uses it in the compiler
as appropriate to keep the event control information in sync.
This patch adds full event control for vectors and parts of a
vector. It also fixes the other non-blocking part select code
to correctly handle a negative offset ([1:-2] of a [4:0] will
have an offset of -2).
When evaluating an expression into an index register bit 4 is used
to determine if the expression had any X/Z bits. In the case of a
constant immediate value this can not happen so make sure the bit
is cleared.
We need consistent pointer output (%p) and under MinGW we need to
us _snprintf instead of snprintf to get this. The recent event
control addition missed this. This has been reported to the MinGW
developers and they are working on a solution.
The previous patch (commit 8b0ca902a6)
dealing with the possibilities of (unsigned long) and (vvp_time64_t)
being either the same or different managed to redefine UL_AND_TIME64_DIFF
in the 64-bit case. This does, of course, trigger a compiler warning.
That warning is repeated on every .cc file with a #include "config.h",
which is to say, just about every file.
This patch inverts the sense of the preprocessor conditional, calling
it UL_AND_TIME64_SAME. No more warnings!
It takes a carefully crafted source file to cause elabortion to make
an arrayed multiple-output gate that is not vectorized into a single
wide gate. But that special case does need to be handled.
While the standard is not completely clear about this, we are making
it an error for a `timescale directive to be inside a (macro)module
definition. This means that all modules and any statements contained
within have a single well defined time unit and precision.
Logic gates usually have one output and several inputs, but a few
have multiple outputs and one input. Since the NetNode objects have
only a single output, handle the case by creating multiple NetNode
objects, one for each output.
A variable that is used to set the delay of a .delay statement
must be scaled to match the local units and for real values
rounded using the precision. This value is then converted to
the simulation precision.
Signals of a nexus must have types that exactly match, but the drivers
of a signal nexus have slightly more subtle rules for the case where
the signal is IVL_VT_LOGIC. Express those rules in the function
check_signal_drive_type, and use it to check the type of constants
driving a signal.
Remove redundant pointer to the containing NetPins object by keeping
the pointer only in the first Link (pin 0) of an array of links. In
this link, replace the pin number with the NetPins pointer, and set
a pins_zero_ flag to indicate that this has happened. This way, only
the first pin in a Link array will have the pointer to the NetPins
that contains the array, and the pointer takes up practically no space
at all.
This class was old, and its original design pulled literally from
the LPM reference. But of nine pins declared, only 4 were used.
Remove all the excess junk and clean up the designed dump handling
of the device.
The r-value expression takes on at least the width of the l-value. If
there is a sized width greater then the l-value width, take that on
instead. But if the r-value is unsized, there are unsized sub-expressions
that cause the expression as a whole to be unlimited width, so elaborate
and evalulate the r-value as lossless.
The true and false expression clauses must have compatible types,
which are not necesarily identical. In particular, VT_BOOL and
VT_LOGIC are compatible for the purposes of ternary arguments. The
test in NetETernary::synthesize was incorrect.
In the process, fix the type handling of NetConst objects to allow
for IVL_VT_BOOL constants. This is information that the downstream
may find useful, so should be handled correctly.
It's processed once by AC_OUTPUT in configure.in and then again
by AC_OUTPUT in tgt-vhdl/configure.in. This is a bug from when I
first started on the VHDL target, and was basing it on the tgt-vvp
code. The call to configure in the tgt-vhdl directory is not
actually necessary either, since it doesn't do any checks not
performed elsewhere, so that should proably be removed later.
This patch pushes the non-blocking event control information to
the code generator. It adds the %evctl statements that are used
to put the event control information into the special thread
event control registers. The signed version (%evctl/s) required
the implementation of %ix/getv/s to load a signed value into
an index register. It then adds %assign/wr/e event control based
non-blocking assignment for real values. It also fixes the other
non-blocking real assignments to use Transport instead of inertial
delays.
The exponentiation operator in VHDL is not defined for numeric_std
types. We can get around this by converting the operands to integers,
performing the operation, then converting the result back to the
original type. This will work OK in simulation but certainly will not
synthesise unless the operands are constant.
However, even this does not work quite correctly. The Integer type in
VHDL is signed and usually only 32 bits, therefore any result larger
than this will overflow and raise an exception. I can't see a way
around this at the moment.
When the -V flag is passed to the iverilog command, we can easily
print the version information for the driver itself, but it is also
valuable to probe all the components that would have been used for
a real compile. So the driver executes the preprocessor and the ivl
core to have them print version information.
The ivl core program also tries to load the target code generator
and get version information to print. For this to work, create a new
optional entry point "target_query" that takes a query key string as
an argument and returns a const string as the result. Use this with
the key "version" to get version information out of the target.
Target selection is done by the DLL target code generator, so there
is no value having a layer of target selection ahead of it. Remove
all that redundant code and simplify the target config files to reflect
this.
It is possible for signe-extend to have a delay attached to it. (Same
for repeat.) Handle it like other LPM devices, by stuffing a .delay
device into the output path of the device, if appropriate.
Stephen Williams
Cary R
Martin Whitaker
Larry Doolittle
Nick Gasson