BOOL values have a specific cast from LOGIC, this node takes care
of it. Also arrange for the elaboration to insert them in the right
planes and for the code generator to generate them.
IVL_VT_BOOL variables at the code generator should generate
.var/2x records so that the run time can do 2-value optimizations
and otherwise support atom2 values.
Fix all the Icarus files that can be so that we do not have any
signed/unsigned compare warnings. It also removes const as a
return qualifier for two routines in discipline.h.
To prevent a force from back propagating we need to keep a BUFZ
that represents a continuous assignment between two nets. This
only effects continuous assignments of the form assign out = in.
In general these are fairly rare so keeping them has minimal
impact on the simulation speed.
This patch adds a check in the vvp back end that a uwire has
at most one driver. Previously this was just converted (with
a warning message) to a wire just after elaboration.
This patch adds the ability to call a system function as a task for
the SystemVerilog generation (-g2009). The return value is really
calculated, but it is ignored.
This patch adds support for a UDP with variable delays. In the process the
intrinsic support for delays was removed from the UDP functor and replaced
with a call to the .delay functor. Both a normal gate and a UDP now use the
same code to generate the delay.
This patch adds checks that the delay count is correct for the
various gates and adds support for a missing variable decay
time. For this case the decay time is the minimum of the rise
and fall times. This is denoted by setting the decay variable
to 0 in the vvp file. vvp notes this and sets an ignore decay
time property in the base delay. This turns off the ability
to set the decay time and the minimum delay calculation will
also update the decay time.
These checks are not needed since we have already verified that
we have a 64 bit immediate value. This is likely old code that
should have been removed when the original functionality was
changed.
This patch pushes delays for tranif gates to the code generator.
We still need to add checks for the number of delays, etc. For
now an error message is printed when a tranif gate is given a
non-zero delay.
This patch modifies the real ternary operator code to support
unlimited tail recursion without overflowing the thread
registers. Head recursion is still limited by the available
registers.
It fixes the thread word checks to use a new define that has
the correct number of thread words (16). It adds a message
instead of just an assert if the thread words are exhausted.
And it also changes some of the error messages to use vvp.tgt
in the message to be consistent with the other messages.
Elaborate conditional assignments with BUFZ devices that do *NOT*
preserve strengths. Add a BUFT (transparent) device that can be
used in those cases where I really need a transparent buffer.
A real delay must be scaled and rounded using the local precision
before it is finally scaled to the simulation time units. This
patch fixes the compiler to do this correctly or generate the
correct code for run time calculated delays. Delays in a CA
already worked correctly. The run time was also fixed to scale
modpath (SDF back annotation) delays correctly.
The functions (malloc, free, etc.) that used to be provided in
malloc.h are now provided in cstdlib for C++ files and stdlib.h for
C files. Since we require a C99 compliant compiler it makes sense
that malloc.h is no longer needed.
This patch also modifies all the C++ files to use the <c...>
version of the standard C header files (e.g. <cstdlib> vs
<stdlib.h>). Some of the files used the C++ version and others did
not. There are still a few other header changes that could be done,
but this takes care of much of it.
gcc on OpenBSD reported shadow warnings for variables, arguments named
log, time and exp. This patch renanes those variables to logic, timerec
and expr.
This patch updates all the Makefile.in files and configure.in
as follows:
Do not use the -Wall warning flag when using the SunPro compiler.
The SunPro compiler uses -xMD instead of -MD.
There are still more fixes needed before Icarus will compile
on OpenSolaris.
The comparison and reduction operators only have a single output bit
that can be delayed.
The comparison of real values always produces a logical value so the
delay type is not dependent on the arguments type.
This patch cleans up some style issues: no need to check that a value
is defined before freeing or deleting it, use C++ style casts, make
sure to NULL terminate strncpy(), empty() is faster than size() for
size == 0 or size >= 0 checks, re-scope some variables, etc.
To match the behaviour of other simulators, delayed bit-based signals
should have the value 'x' and delayed real valued signals should have
the value 0.0 until the true initial value has propagated. This patch
provides this behaviour.
When building a modpath the source for the modpath must have the
same scope as the modpath. This is required to make the back
annotation work correctly (have the correct names).
This patch enhances elaboration to drop/ignore zero replication
count constants. Not doing this was causing problems later in
the compiler. We still pass non-constant expressions since
both user and system functions must be run for their possible
side effects. Constants can never have a side effect so just
dropping them is acceptable.
This patch adds support for passing the delay selection to vvp.
It adds a new header :ivl_delay_selection "<value>"; that has
the values TYPICAL, MINIMUM or MAXIMUM depending on the -T
flag to iverilog. This information is needed by $sdf_annotate
to select that appropriate value for a triplet when
"TOOL_CONTROL" is specified (default).
This patch mimics what was done for normal assignments to get the
width correct for nonblocking assignments when converting a real
r-value to a l-value vector.
When selecting bits from unsized literals, we do not put a limit
on the size of the literal, so there is no top above which we
stop getting literal bits.
When handling the $signed/$unsigned system functions, the compiler
was applying the new signed/unsigned property to the NetExpr object
representing the input argument. This caused the input argument to
be evaluated incorrectly. This patch fixes this by applying the new
property to the NetExpr object created to pad the result to the
required size.
In testing this fix, it was also discovered that the width of the
input argument expression was not being calculated correctly. This
patch also fixes this issue.
The padding for a signal select was using the signal to determine
if the padding should be singed or not. In reality this should be
unsigned padding unless the select was enclosed in a $signed().
In combination with the patch to make all operations on thread words
operate on 64-bit values, this patch ensures casts between real values
and large vector values work correctly.
When evaluating a function argument expression we need to use either
the expression width or the argument width which ever is larger. This
matches the way normal assignments work. We then only take the bits
needed at the end.
These explicit dependencies are not normally needed (because they
are covered by automatic dependency generation) but when the "-jN"
flag is passed to gmake, they help gmake schedule parallel builds.
(cherry picked from commit 5479aaf721)
Stephen Williams
Larry Doolittle
Cary R
Martin Whitaker