Currently, when a variable expression is passed to a system task,
the expression value is stored in thread memory. Values stored
in thread memory cannot safely be passed to $strobe or $monitor,
because the thread memory may get reused or deallocated before
the $strobe or $monitor task actually executes. As a temporary
measure, we just trap this case and terminate with a "sorry"
message. A proper fix would require the expression value to be
calculated at the time the $strobe or $monitor executes, not at
the time it is called.
This patch implements the $countdrivers system function. It does not
yet support wires connected to islands (and outputs a suitable "sorry"
message when this is detected).
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.
The standard specifies that the size of a vecval should be calculated as
(size - 1)/32 + 1. When size is a PLI_INT32 this is needed to prevent an
overflow, but when the size is unsigned this can be simplified to
(size + 31)/32 since the size must fit into an integer, but we have an
extra significant bit in an unsigned so no overflow can happen.
This patch changes the code to use the correct version of the equation
depending on the context.
The previous patch does this in vvp/vpi_priv.cc
Not all the lex/yacc (flex/bison) targets were using a consistent syntax.
This patch fixes that and explicitly serializes the *.c/*.cc and *.h build.
Not doing this was causing problem when using make -j. The issue appears to
be that if two targets are specified for a rule (e.g. file.cc file.h: file.y)
make does not realize they are both built by the same call so the rule is
executed twice. Once for the .cc target and once for the .h target. This is
not a problem for a serial build. To work around this only use the .c/.cc
file in the main target and then make the .h file depend on the .c/.cc file
as a sub-target.
When scaling a time value we would often use the power operator to
create constants 10**-N that were then multiplied with the original
value. The problem with this is that there is some errors in the
representation of the fractional number. It is better to create a
integer value 10**N and then divide the original value by this
exact constant. You still have the calculation error, but the scale
value is now an exactly real value.
Add support for %m, suppression '*' and a maximum field width along with
a number of other fixes/enhancements. There is still no support for
%u, %v or %z.
Some of the last changes I added to the enumeration next()/prev() code
introduced a memory leak under some situations. This patch fixes the
leak by freeing the iterator before the new one is created.
Add an implementation for the enumeration name() method. This currently
only works if the context defines the return width (e.g. the result is
assigned to a variable). It does not work in a self-determined context
(e.g. as an argument to a system function or in a comparison). This is
a limitation in the compiler/code generator/run time not the method
implementation provided here. We may need full string support to make
this work 100%.
The standard defines how to calculate the name for an access function
or iterator if one is not given. It is supposed to be vpi followed by
the words in the name with each word capitalized. For the one to many
(iterator) interface from the enumeration typespec to the individual
constants this is vpiEnumConst not vpiMember.
Rework the actual next() and prev() methods to correctly process the
numeric count argument. Also rework the compiletf routine to give better
error messages and combine the call routine for the two methods.
Add a compiletf routine that checks the arguments and then report that
the name() method is not currently implemented.
The vpiDecStrVal case for the get_numeric() function needs to use the
existing string width as the minimum result size. -1 can be represented as
a signed value with a width of 1. This gives a display width of -1 which
is too small for the -1 string value. This was creating valgrind issues.
In general the string value should be the minimum so this is a safe change.
Cary R
Martin Whitaker
Stephen Williams
Arun Persaud
Larry Doolittle