In previous incarnations of the vvp runtime, bit vectors were passed
around as arrays of unsigned char that charried bit4 vectors. That
is no longer used. Remove the last vestiges of that dead code.
Remove dependencies on vvp_bit4_encoding outside of the vvp_net
core types. The table_functor_s class was the worst offfender and
was barely used, so it is now removed completely. There are a few
opcodes in vhtread.cc that also make vvvp_bit4_t encoding
assumptions (and used casts) and those have been fixed. There
were also various VPI interface functions that are fixed.
The vvp_vector4_t holds 4-value logic. This patch changes the encoding
of 4-value bits in the vector to use separate A- and B bit vectors,
with the B- vector signaling the A- bits that are not 0/1. This
allows rapid conversion to 2-value logic, and rapid tests for X
and Z values.
This patch fixes deassign to allow it to unlink from a driver.
It also zeros the cassign_link and force_link pointers after
they have been unlinked. Not doing this will cause an assert
if deassign/release are called multiple times (variable only).
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.
Rework the MUXZ and MUXR code to use an enum instead of plain
integers for the select input state. This makes it more obvious
what is actually going on.
This patch adds a flag to the MUXZ object to make sure that it will
run at time zero if needed. If this is not done the default Z result
may not be overridden by an X result.
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 add (I believe back in) the < and > characters to the
general T_SYMBOL regular expression. The match was also moved after
the special T_SYMBOL cases so that flex would match them correctly.
Flex matching rules are longest or if a tie the first.
vvp did not have the ability to handle real parameters.
This patch fixes that omission. Parameters are only used
by vpi calls to get compile time information.
Threads used to be deleted when they finished processing code.
The problem with this is that some of the code could be
rescheduled to run at rosync ($strobe, etc.). This allowed the
thread data the code depended on to be reaped too soon. This
patch uses a new queue to schedule thread deletion. The queue
is processed after rosync has finished.
This patch makes the muxz and muxr functors schedule events
instead of directly calling vvp_send_*(). This prevents the
code from going into an infinite loop when the output feeds
back to the select.
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.
vpi_put_value can mimic force and release with vpiForceFlag and
vpiReleaseFlag flags to the vpi_put_value call. With this patch,
the infrastructure is added to allow the flags argument to be passed
to the dispatched put_value function, and for signals handle those
flags as force/release of a net.
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).
draw_number_bool64() in tgt-vvp/eval_bool.c was using %ix/load to
load immediate values into registers greater than three. The problem
was that of_IX_LOAD() in vvp/vthread.cc was masking off the upper
bits. This was putting the results in the wrong register. This patch
removes the bit masking from of_IX_LOAD() and updates the %ix/load
documentation.
This patch fixes two problems. The first is that thr_check_addr()
was being used inconsistently. It should be passed a real address,
but the resize of the vector should be at least one more than this
address. The extra and unneeded CPU_WORD_BITS was also removed
from the routine.
The second problem involved an invalid memory access in
vvp_vector4_t::set_vec() when the vector being copied was an integer
multiple of the machine word width. Under this condition there would
be no remaining bits that needed to be copied but the routine was always
trying to copying some remaining bits. This code is now only executed
when there is a remainder.
Neither of these appear to be causing runtime problems. The second one
was found with valgrind. The first were found while tracking down the
second problem.
This patch adds the power operator for signed bit based values
in a continuous assignment. It also fixes a few other power
expression width problems. The expression width is still not
calculated correctly, since the correct method can produce huge
possible bit widths. The result is currently limited to the width
of the native long. This is because lround() is used to convert
from a double to an integer. A check in the code generator protects
the runtime from this limitation.
This patch adds the power operator for unsigned bit based values
in a continuous assignment. It also refactors the power code for
normal expressions and continuous assignments.
This patch adds bit based power support to normal expressions.
It also pushes the constant unsigned bit based calculation to
the runtime until the bit based method can be copied to the
compiler. Continuous assignments also need to use this type
of calculation.
vvp/main.cc was including asm/page.h on GNU/Linux
systems, though that file does not often exist and
is not necessary.
Signed-off-by: Michael Witten <mfwitten@mit.edu>
This patch makes sure the delay is calculated correctly when only some
of the bits change and you are comparing against the initial (t0) value.
Basically you have to check the initial value against all the bits in
the new signal not just the first bit since the order that bits change
is not deterministic.
Allow user defined functions to take real value arguments and return
real value results in net contexts. Use the data type of the nets
attached to the ports to define the data types of the arguments and
return value.
When conditional delays are in use, it is sometimes possible for there
to be no delays available for a given input event. In that case, skip
the delay processing for that case instead of crashing.
Rework the encoding of a real value in the Cr<> label to be similar to
the format used by the %loadi/wr instruction. This mantissa-expoment
format better carries all the bits of the desired real value with
plenty of fidelity and range.
This patch adds a new opcode %load/avp0 that is used to load a
word from an array and add a value to it. %load/vp0 was
changed/fixed to do the summation at the result width not the
vector width. This allows small vectors to index large arrays with
an offset. A few errors in the opcodes.txt file were also fixed.
This patch schedules the input value change to .sfuns calls to avoid
potential recursion problems. It also cleans up two put_value calls
that did unneeded loops when putting VectorVals and the width was
greaten than 32 bits.
This patch adds a new flag to vvp "-n" that can be used to make
$stop and hence <Control-C> act like $finish. This may be desired
when using vvp in a non-interactive environment.
tgt-vvp/eval_expr.c uninitialized variables
vpi/sys_display.c uninitialized variables
vvp/vpi_priv.cc deprecated string constant usage
vvp/vpi_vthr_vector.cc deprecated string constant usage
the last entry invokes vpip_name_string() and uses const char *
in the same way as the other 9 callers in vvp/*.cc, the only
difference is that the argument is static instead of computed.
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.
With this change, local symbols are not emitted in the vvp target,
but are marked as local. When thus marked, the vvp run time does not
offfer any VPI access and the signals (net or var) are effectively
invisible.
The recent changes to vpi_get_str had a minor problem that was
causing a core dump when trying to get the vpiFullName of an
arrayed signal. Basically vpi_get_str is not reentrant so the
name must be duplicated. It must also be duplicated to work with
the free in the code (do not free a result_buf).
Gets rid of a few warning: deprecated conversion from string
constant to 'char*', follows IEEE 1364-2001C 27.10 in more cases,
and fixes at least one real bug (look at the previous use of
strdup/strcat in real_var_get_str() and signal_get_str()).
This patch fixes a number of problems associated with the various dumpers.
1. It catches the problem uncovered in pr1809904 and prevents the core
dumps from happening. It prints a warning message if you try to change
the file after the program has started dumping data to the file.
2. It makes all the dumpers work in the same manner. Before the VCD
$dumpfile was processed at compile time, but the LXT/LXT2 versions
did this at run time. The correct place for this is the run time so
that you can pass the task a calculated name.
3. All the dumpers use common compiletf routines located in vcd_priv.c
4. Make the LXT/LXT2 $dumpfile commands only get the file name and
let $dumpvars actually open the file. This matches the VCD code.
5. Fix the $dumpfile code to allow calculated file names.
6. Make dumpvars without a scope/variable match all toplevel modules
not just the toplevel module the $dumpvars was located in. This
now matches the standard (2001).
7. Simplify the no dumper code (vcdoff.c) and add missing functions.
8. Cleanup the code and messages.
9. vvp can take -none for no dumper.
This patch fixes another minor problem introduced by the process
end of simulation events. Specifically if the compilation has
indicated we should not run do not even start the main event loop.
Parse SDF file annotations of edge sensitive delay paths.
Add vpi support for getting the specified edge sensitivity of
an edge sensitive path, and annotate paths with proper attention
to the edge that is specified for the path.
When loading a part select from the least significant bits, it is
OK to use the %load/v instruction to strip the high bits off. This
allows the zero-based part select to work in one step, without
loading excess bits.
The %ix/getv instruction loads an integer register directly from
a signal vector. This is an optimization that an index register
is loaded from an expression is only a signal. It avoids the thread
vector space.
Use the new array VPI functionality (vpiIndex, vpiParent, vpiArray)
to dynamically generate array word names. The old patch to implement
was mostly reverted.
Add the array related VPI calls. These will be used to generate
the array word name only as needed to conserve space. This patch
also makes scanmem3 from the vpi test work correctly after a
slight gold file update.
Where and expression is an immediate value added to a signal value,
it is possible to optimize them to a single instruction that combines
the load with an add at the same time.
The functor counters were left over from the v0.8 release. Rework
the counters to be relevent to the current state of vvp.
Signed-off-by: Stephen Williams <steve@icarus.com>
This patch adds the ability to dump array words. The words are only
dumped if they appear in a $dumpvars() statement (they are not dumped
by default). The name used for the word is <array_name>[<index>], so
you can get unexpected name conflicts.
There is also a slight increase in the memory requirements since each
array word now keeps its own name information. In the future we would
like to change this, but that is a much larger rewrite of the array
code in vvp.
This patch also needs the "Prefix escaped identifier ..." patch to
work correctly (the array word name is an escaped identifier).
Implement extended vvp command line options to control the amount
of detail that the sdf annotator emits while parsing the source
file.
Signed-off-by: Stephen Williams <steve@icarus.com>
Pass parsed SDF delays into the vvp run time as vpiScaledRealTime
variables, and handling the mapping of 2-values to 12-delays.
Signed-off-by: Stephen Williams <steve@icarus.com>
This was causing a core dump for a number of the vpi test cases.
The problem was that they did not need the simulation time, so it
was being set to NULL. The problem was the EndOfSimulation callback
was always setting cb_data.time to the current time. A big problem
when the pointer was NULL. The solution is to only set the time
when the pointer is not NULL
String values are known to be 2-value bits, so they are natural
candidates for using the movi instruction to load the value in
far fewer instructions. With this patch, up to 16bits (two bytes)
at a time can be loaded per instruction.
Signed-off-by: Stephen Williams <steve@icarus.com>
A previous patch I submitted to try and keep the $finish time
events missed the case of an infinite loop that did not advance
the micro time step which then prevents the debugger from
generating a finish (you can interrupt an infinite loop, but you
could not finish out of it). This patch adds a check for a
finish after each debugger call to fix this problem.
When nets are forced by non-constant expressions, the value is linked
to the destination net through a force_link. This patch adds the code
needed to unlink a force/link so that release and new force/links can
work. This fixes pr1735836.
Signed-off-by: Stephen Williams <steve@icarus.com>
Stephen Williams
Cary R
J Varshney
Larry Doolittle
Michael Witten