This patch extends the compiler to support all specparam declarations
allowed by the 1364-2005 standard. For compatibility with other
simulators, it allows specparam values to be used in any constant
expression, but outputs a warning message and disables run-time
annotation of a specparam if it is used in an expression that must
be evaluated at compile time.
This handles a few cases where the non-constant bit selects are
in the final index. This doesn't handle all the cases of packed
arrays, but it handles some common cases.
This patch changes the method used to signal that a constant expression
is being elaborated from flags stored in global variables to flags
passed down the call chain. It also generates more informative error
messages when variable references are found in a constant expression.
During elaboration, it is sometimes efficient to collapse a
collections of PV drivers to a net to a single concatenation.
This removes a bunch of resolutions and other nodes, and also
is the only way that 2-value logic should work.
The compiler currently performs parameter expression elaboration before
performing parameter overrides. This means that the information needed
to correctly determine the expression type and width may not be available
at the time elaboration is performed. This patch reworks the code to
delay elaboration until after all overrides have been performed. It
also provides a new -g option that controls how the width of parameter
expressions is calculated when the parameter itself is unsized.
This patch covers more than it should. It removes many of the -Wextra
warnings in the main ivl directory. It also makes some minor code
improvements, adds support for constant logicals in eval_tree (&&/||),
adds support for correctly sign extending === and !==, it starts to
standardize the eval_tree debug messages and fixes a strength bug
in the target interface (found with -Wextra). The rest of the warnings
and eval_tree() rework will need to come as a second patch.
When enum names are used as r-values in expressions, use their
values. Treat the enum names similar to (but not exactly as)
localparams so that they fit into the rest of the elaboration
flow naturally.
BOOL values have a specific cast from LOGIC, this node takes care
of it. Also arrange for the elaboration to insert them in the right
planes and for the code generator to generate them.
A real delay must be scaled and rounded using the local precision
before it is finally scaled to the simulation time units. This
patch fixes the compiler to do this correctly or generate the
correct code for run time calculated delays. Delays in a CA
already worked correctly. The run time was also fixed to scale
modpath (SDF back annotation) delays correctly.
This patch add code to print a warning message if it finds both a
default and `timescale based delays. The -Wall or more specifically
the -Wtimescale flag can be used to find the module with the missing
`timescale directive.
This patch adds messages in various places to warn that constant
user functions are not supported. It uses a global variable to
indicate when we are in a constant context. This is a bit of a
kludge, but works well without needing to change a bunch of code.
It is interesting to note that ports are elaborated late enough
that if we had the constant function evaluation code they would
evaluate correctly. This also applies to the function return
range, the concatenation repeat, specparams and initial values.
Signal definitions are early enough that elaboration is what is
failing because the function body is not available (has not been
elaborated). The same thing applies to both parameters and
localparms.
This patch adds logical support for real values (!, && and ||). It
also prints an appropriate error message when a real value is
incorrectly given to an operator that does not allow real arguments
(bit-wise, reduction, shift and repeat/concatenation).
This fixes up the elaboration of binary expressions found in
parameter expressions. Parameter expressions are special because
they elaborate early, before all the other parameters are necessarily
completed.
unary expressions that have problems should not assert in the
test_width method. Instead, let the error propagate back and be
handled during expression elaboration. This found a few places
where expression widths/types weren't probed before elaboration.
When padding a signal or when creating a local signal the file and
line information should be related to where the new object was
created not the signal value it is being created from.
This patch modifies the NetE* pad_to_width() routines to take a
LineInfo object to set the location to the correct value.
It fixes some set_line() calls to use the correct location.
It fixes ports to not set the file/line information if it is
already defined. Doing this was causing the definition of
signals to become the instantiation instead of the real
module declaration.
This patch splits any VVP net functor that needs to access both
statically and automatically allocated state into two sub-classes,
one for handling operations on statically allocated state, the
other for handling operations on automatically allocated state.
This undoes the increase in run-time memory use introduced when
automatic task/function support was first introduced.
This patch also fixes various issues with event handling in automatic
scopes. Event expressions in automatic scopes may now reference either
statically or automatically allocated variables or arrays, or part
selects or word selects thereof. More complex expressions (e.g.
containing arithmetic or logical operators, function calls, etc.) are
not currently supported.
This patch introduces some error checking for language constructs
that may not reference automatically allocated variables. Further
error checking will follow in a subsequent patch.
Later passes need the intermediate results for width and size so that
some special cases, were self-determined arguments occur, can be
processed properly during elaboration. This can be especially tricky
and interesting for ternary expressions.
There are cases where the r-value doesn't pad itself to the width
that is requested by the call to elaborate_expr. This impacts the
elaboration of PGAssign. Pad/sign extend as appropreate.
The expr:::synthesize methods need not deal with saturating left or
right shifts if they are dealt with early, in elaborate_expr methods.
So the elaborate_expr for shift takes on much more responsibility.
Since NetExpr::synthesize methods were rarely used, then had a lot
of bugs. Now that continuous assign uses these methods, these bugs
must be fixed.
Binary and Unary minus properly pad/extens its arguments,
Case compare generates correct code,
Divide properly takes on signed flag,
Signed right shift sign-extends its argument to prevent loss of sign bits
and uses the NetSignExtend instead of simple padding,
Use the correct target node for reduction NAND,
Properly handle constant arguments of NetESelect
Handle some exressions that were not handled before, include abs()
and POW.
This patch adds .cast/int and updates .cast/real to act as a local
(temporary) net and to support either a signed or unsigned input.
The vvp_vector4_t class not can convert an arbitrarily sized double
to a vector value. This removes the restriction of lround().
Also document the new statements.
This handles the general case of a non-real operand to a real-valued
division. This can turn up if only 1 operand of a divide is real. In
this case the division as a whole is real and the other operand must
be cast to real.
This method creates an extra node, but it should be a very compact
node and this node does no evaluation tricks so in the run time should
be no more expensive then folding the cast into the .arith/div.r itself.
Part selects to signals are allowed to be off the ends of the signal
itself. The bits that are beyond the vector return X. This may mean
creating constant X bits on one or both ends of the result.
Before this, the types of parameters were always logic, only the
width and signed-ness could be controlled. A parameter may take
on implicit real values if the expression were real.
With this patch, the type for the parameter can be explicitly set
to logic or real. This also means that the parameter real valued
expressions need to be more crefully treated, possibly with casting
integral expressions to real values, or real expressions to integral
values.
Logical and/or take as inputs condition expressions, which are scalar
expressions. Be sure to reduce vectors using proper logic to get the
right condition value.
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).
Handle real valued expressions in vector declarations. Also clean
up the handling of vector declaration expressions.
Signed-off-by: Stephen Williams <steve@icarus.com>
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.
pform and netlist for gates.
Change vvm constants to use the driver_t to drive
a constant value. This works better if there are
multiple drivers on a signal.
Stephen Williams
Arun Persaud
Martin Whitaker
Larry Doolittle
Martin Whitaker
Cary R
steve