Probe the widths of the case statement expressions. The expressions
are self-determined in that context, but the probe is needed to
setup the expression types.
Verilog generate schemes support a special case where conditional
generate schemes that contain only a nested conditional generate
scheme do not create a new scope. Instead, it relies on the nested
generate scheme to generate the scope.
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.
A simple typo in the rhs of an expression would crash the compiler.
Example:
module crash3;
reg clk;
integer cnt1=0;
always @(posedge clk) begin
cnt1 <= (cnt==81) ? 0 : (cnt1+1);
end
endmodule
This patch adds a number of compile and run-time checks for illegal
uses of variables declared in automatic tasks and functions. It
also adds a check for event expressions in automatic tasks that use
features not yet supported in VVP.
The goal is to completely remove the svector class because the standard
vector class works perfectly well. This removes the uses in the Module.h
header file.
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.
Put together the infrastructure for elaborating analog statements,
including create the NetAnalogTop objects that hold analog statements
and are in turn held by the design.
While doing this, clean up the various unique initial/always enumerations
to use the ivl_process_type_t type.
This fixes the sign calculation for port padding. It also reports if
the padding will be signed or not in the warning message. The inout
calculation may not be correct. It requires both the signal and the
port to be signed, but inout is not currently padded anyway.
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.
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.
This patch removes all the checks for constant expressions performed
during the parsing phase, as these checks are (mostly) repeated during
elaboration. It adds the missing check in the elaboration phase (the
RHS of a register initialisation), and improves the error reporting
and error recovery in other checks.
This patch fixes pr2132552, which was caused by a fault in the parser
constant expression checking.
In assignments, the expression width may be defined by the width of
operands, and not that of the l-value. Choose whichever is creater and
set (or pad) the expression to that width.
This patch pads inputs and output ports correctly when the port
and the port expression have different widths. It does not fix
inout ports.
It also sets the file and line number information in the unsigned
pad_to_width() routine.
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.
Widths of real values are always 1. When paired with vectorable types
in expressions, the vectorable type is processed as losslessly self-
determined. ("unsized" in the test_width methods.)
the PGAssign elaborate method used the test_width to get the width
of the r-value expression. This should be completely sufficient to
get the width of the expression, so always use a defined width to
elaborate the expression.
It takes a carefully crafted source file to cause elabortion to make
an arrayed multiple-output gate that is not vectorized into a single
wide gate. But that special case does need to be handled.
Logic gates usually have one output and several inputs, but a few
have multiple outputs and one input. Since the NetNode objects have
only a single output, handle the case by creating multiple NetNode
objects, one for each output.
The r-value expression takes on at least the width of the l-value. If
there is a sized width greater then the l-value width, take that on
instead. But if the r-value is unsized, there are unsized sub-expressions
that cause the expression as a whole to be unlimited width, so elaborate
and evalulate the r-value as lossless.
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.
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.
This patch moves the always zero or possibly zero delay checks
to a point after the circuit is full elaborated. Before it
could try to check tasks that had not already been evaluated
resulting in a crash.
In continuous assignment, the width of the expression needs to come
from the expression itself, and not just from the width of the l-value.
Use the PExpr::test_width method to get the width of the expression
to pass to the elaborate.
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.
Because Icarus tries to elaborate as much as it can even after
an error has occurred we need to check for these errors during
elaboration. This patch prevent an undefined identifier from
crashing the compiler.
When the continuous assignment is signed, then sign-extend the r-value
in the few cases where the expression is stubbornly smaller then the
desired width.
Stephen Williams
Cary R
Larry Doolittle
Martin Whitaker