This patch implements the swrite* and sformat system tasks. It also
makes $simtime distinguishable from the other integer time tasks.
This was needed to get the correct time units when $simtime was given
as an argument to $swrite*. The string constant code was also modified
to allow a string to be returned as a vector (0/1 bit pattern).
Here are some more specifics about the swrite* changes.
1. They do not share formatting code with the other display functions,
so they may/will produce different results.
2. All %{alpha} codes allow a width and justification. Others have been
enhanced (%t allows the default width and precision to be overridden,
time functions print with time formatting, better error checking and
messages, etc.).
3. %u and %z formatting codes have been added. It is important to note
that these two formats can produce embedded NULLs, since these
functions are returning a string anything after the first NULL will
not be reachable! memcpy is used instead of regular string processing
where needed so that the original string will contain the total
result. The size returned when the string is created is the true
length. A warning will be printed if a string with embedded NULLs is
produced (strlen() does not match the true length).
4. Real numbers are printed with %g instead of %f.
Once this new formatting code has been evaluated we should incorporate
the changes/fixes into the formatting code for the other functions or
the other functions could be modified to use this new code. The true
string length is available so we should be able to work around the
embedded NULL problem.
The standard states that the seed for the random functions should be
an integer/time variable or a register. This patch fixes the compiletf
routines to check for this. There is also a small patch to
vvp/vpi_signal.cc that removes an assert that was failing and replaces
it with appropriate code. The assert was verifying that the source was
not bigger than an integer. The problem with this is that a time
variable or register may be bigger than an integer. I altered the code
to remove the assert and copy only the lower (8 * sizeof integer) bits.
The potential overflow/loss of precision is not checked. This passes
the regression tests.
Delat the compiletf calls until after all the label references
are resolved and link bindings are complete. Otherwise, there may
be dangling references.
Signed-off-by: Stephen Williams <steve@icarus.com>
This patch adds a compiletf routine to the $deposit system task and
simplifies the calltf routine. It also patches the constant string code
to return an appropriate integer value when needed. A number of compiletf
routines that check for this can now be simplified since this (string
constants) no longer causes an assert in an integer environment.
The argument passed to $finish and $stop is not currently used, but it
is now passed down to the functions that may someday do something
useful with it (schedule_finish() and schedule_stop() in vvp/schedule.cc).
Add the missing probabilistic functions and add compiletf routines
for all the functions. The original calltf routines have been
modified as appropriate. The base functions are straight copies
from the standard. I have visually verified the curves with 5,000
points and they look correct.
Even though vpiFinish does not currently do anything with it's
argument I thought it would be best to have them all be in the
correct range [0, 1, 2], so they have been updated as appropriate.
Backslash-escapes are processed early, during elaboration, so that
escaped characters show up in all places with the calculated value.
This means the $display formatting will get processed strings and
should not process back-slashes again.
Signed-off-by: Stephen Williams <steve@icarus.com>
Cary R
Martin Whitaker
Stephen Williams
steve