This patch adds blocking repeat event controls and also makes the
base repeat statement sign aware. If the argument to repeat is
negative (it must be a signed variable) then this is treated just
like an argument of 0 (there is no looping). Doing this allows us
to model the repeat event control as follows.
lhs = repeat(count) @(event) rhs;
is translated to:
begin
temp = rhs;
repeat (count) @(event);
lhs = temp;
end
This patch also pushes the non-blocking event control
information to the elaboration phase where it will report they
are not currently supported.
Actually, the immediate value handling is a little chaotic and should
be cleaned up. This patch opens the door for allowing signed immediate
values, and uses them in a few places where they are explicitly handled.
We must go through the opcodes that can take immediate values and make
explicit whether they are signed/unsigned/etc, and what their size
limits are.
Memory words may have part selects assigned, but the code messed up
the testing for the validity of the part select base. This fixes do
detect constant bases so that base validity tests are handled at
compile time.
Save tons of space per memory word by not creating a vpi handle for
each and every word of a variable array. (Net arrays still get a
vpiHandle for every word.) The consequence of this is that all
accesses to a variable array need to go through the indexing.
This commit handles the most common places where this impacts, but
there are still problems.
Detect thread bit allocation failures and fail gracefully. Print an
error message that points at the expression in question, and return
with an error code so that the compiler exits with an error.
This patch adds the ability to assign/deassign a bit or part select.
It also cleans up the code and fixes some problem in the forcing of
strength aware nets.
This patch adds a %assign/av/d opcode. This is a version of %assign/av
that allows a delay expression. Ultimately this allows a dynamically
indexed array to have a delay expression (non-constant delay value).
This patch removes the overly optimistic lookaside save for a signal
that has been set (%set/v). This is incorrect because if a force or
assign are active the value will not be set as expected.
This patch adds functionality to do a bit or part select release
when a constant value is forced to the net/register. It also adds an
error message when the user tries to force a signal to a bit/part
select. This is not currently handled by the run time, so is now
caught in the compiler (tgt-vvp). Where when this functionality is
needed, it will be easy to know what to do instead of trying to track
down some odd runtime functionality.
What this all means is that you can force a signal to an entire
signal or you can force a constant to any part of a signal (bit,
part or entire) and release any of the above. Technically the
release of a constant value does not have to match the force.
The runtime verifies that if you are releasing a signal driver
it is being done as a full release. I don't see an easy way to
check this in the compiler.
To fix the signal deficiencies we need to rework the force_link
code to allow multiple drivers and partial unlinking. Much of
this is in the runtime, but the %force/link operator may also
need to be changed like I did to the %release opcode.
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).
This patch adds a real error message instead of an assert when
someone attempts to release a part or bit select. I plan to work
on the real functionality soon.
This patch adds support for the following statement:
<vector>[<i>] <= #<delay> <value>.
It is a copy with slight modification of code from the next
else/if clause.
Rework the ivl_file_table_* interface to be more generic and easier
to use. Also all the vvp examples except for memory.vvp have been
fixed to run correctly with the current vvp. Someone with a bit more
experience will need to fix memory.vvp.
Add the vpiFile and vpiLineNo properties to system functions.
Most other objects have stubs that return "N/A"/0. Interactive
functions (called from the debugger) use <interactive> for the
file name.
This patch fixes/enhances the array part select code. It also
verifies that any lval array index in a continuous assignment
is a constant value. Also, %set/av now uses index register 1 as
described in the documentation (as a bit offset).
more general concept of arrays. The NetMemory and NetEMemory
classes are removed from the ivl core program, and the IVL_LPM_RAM
lpm type is removed from the ivl_target API.
Cary R
Stephen Williams
Larry Doolittle
steve