This patch evaluates the whole concatenation expression and
makes the concatenation padding sign aware. This is needed
when $signed({...}) is passed as an argument.
A repetition is just N copies of the base expression not N
evaluations of the base expression. This is only a problem
when functions have side effects. It's also faster to copy.
The evaluation must also be done when the replication count
is zero (see 1364-2005).
This was incorrectly using the expression sign not checking if
the two sub-expressions are both signed. This likely used to
work, but in the context of $signed which sets the expression
to signed so we can have a signed expression without both
sub-expressions being signed.
This is mostly a minor definition change in the parsing of literal
numbers by the vvp lexor. Allow for 64bit numbers in the .delay
records, and have the code generator also able to cope with the
situation.
This patch adds support for 64 bit non-blocking delays in procedural
code. We fixed the procedural delay operator (blocking delays) earlier.
This patch mostly mimics what was done there. The continuous assignment
delay operator still needs to be fixed.
Continue cleaning up shadowed variables, flagged by turning on -Wshadow.
No intended change in functionality. Patch looks right, and is tested
to compile and run on my machine. No regressions in test suite.
This patch set covers C code, with the notable exception of
vpi/lxt_write{,2}.c.
The power operator is different in that it uses the signed version
if either of it's arguments are signed. This patch fixes the code
generator to do this correctly.
It is ot uncommon for the arguments to logical or to leave stuff
in bit registers 4-7. Allow the lor itself to take advantage of
that to save some %mov instructions.
When padding expressions, pre-allocate the target space and calculate
the sub-expression directly into the target. Then pad from there. This
saves a move into the result space.
In a procedural single bit non-negated reduction (&, | or ^)
we need to translate a 1'bz to a 1'bx. The easiest way to do
that is with two %inv opcodes. This patch modifies the code
generator to do this for this very special case.
In the vvp code generator, when zero/sign extending a sub-expression,
the sub-expression is first evaluated and stored in one location in
the thread vector store, then is copied and extended into a second
location. The storage used for the initial sub-expression evaluation
is never deallocated.
Even on 64 bit machines immediate values should be limited to
32 bits so that the a.out file will run correctly on a 32 bit
machine. This patch fixes a number of places where the code
generator was not checking for/observing this.
When evaluating an expression into an index register bit 4 is used
to determine if the expression had any X/Z bits. In the case of a
constant immediate value this can not happen so make sure the bit
is cleared.
This patch pushes the non-blocking event control information to
the code generator. It adds the %evctl statements that are used
to put the event control information into the special thread
event control registers. The signed version (%evctl/s) required
the implementation of %ix/getv/s to load a signed value into
an index register. It then adds %assign/wr/e event control based
non-blocking assignment for real values. It also fixes the other
non-blocking real assignments to use Transport instead of inertial
delays.
Nothing to do with tab width! Eliminates useless
trailing spaces and tabs, and nearly all <space><tab>
pairings. No change to derived files (e.g., .vvp),
non-master files (e.g., lxt2_write.c) or the new tgt-vhdl
directory.
Low priority, simple entropy reduction. Please apply
unless it deletes some steganographic content you want
to keep.
Be more sophisticated with the code generated for constant values.
When values are large, use an optimal mix of %movi and %mov
instructions to get the desired value, no matter what the content.
The load-and-add for vectors %load/vp0/s can be combined with the
load-and-add for array words, and the %load/avp0/s added to round
out the combinations. This can make for fewer instructions when
words are padded in arithmetic expressions.
The %load/vp0 instruction adds a signed value to the signal value being
loaded, but it doesn't allow for a signed source vector. Add the
%load/vp0/s instruction that pads the loaded vector, and add the code
generator details to properly use it.
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.
The part select of a vector is converted by the compiler during
elaboration to a 0-based canonical address. But since it is legal
to address bits below the LSB, the canonical address can be negative.
So make the part select base for selecting from signals work with
signed arithmetic and make the code generator generate negative
indices when needed.
The handling of immediate add used to do 16bits at a time. When it went
up to 32bits, the need to work in chunks vanished, but the chunk handling
was still there, this time shifting by 32, which causes problems on 32bit
machines. Simplify the %addi handling to avoid this.
Clarify that operands are typically 32bits, and have the code generator
make better use of this.
Also improve the %movi implementation to work well with marger vectors.
Add the %andi instruction to use immediate operands.
It is possible for an array to have 1 word in it, so using the array
count to detect an array is incorrect. Use the ivl_signal_dimensions
function, which is there exactly for that purpose.
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.
It is a quirk of the $signed() system function that the argument
is converted to signed, but the operation that is performed is
not changed. So arithmetic operators on unsigned arguments inside
a $signed() expression still perform unsigned arithmetic.
When generating a real expression you can have bits of the
expression that use vector only operands. When this happens
evaluate that part of the expression as a vector and then
convert it to a real value.
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 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).
The dup_expr() function for NetESignal was not copying the word_
expression. This would cause an individual array access to turn
into an entire array access. The file and line information was
also not being set correctly.
An assert() in tgt-vvp/eval_expr.c was also replaced with an
exit() since the appropriate information was already being
printed.
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.
The IVL_EX_NONE type was not displaying any message and default did not
use the new ivl_expr_{file,lineno} functions to get the source location.
This patch remedies these problems.
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.
This patch adds a check and prints a warning message when the power
operator is used with unsigned bit based values. It also fixes a couple
of typos and adds an asserts if the above power operator happens to
get to the tgt-vvp back end.
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.
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.
Cary R
Larry Doolittle
Stephen Williams
Martin Whitaker