To be strictly compliant with the standard and compatible with other
EDA tools, unsized numbers should be treated as having a fixed size
(the same size as an integer). The -gstrict-expr-width option is
extended to allow the user to enable this behaviour.
This option is intended to make it easier to compare results from
Icarus with results from other simulators. For now, the only effect
it has is to change the default format for displaying real numbers
when no format string is supplied.
When you have an expression like this (extreme example):
a[idx[1]][idx[2]*4 +: 4] <= #(idx[3]) 4'ha;
where a is a reg array and idx is a reg or net array. The retrieval
of idx[2] was clobbering index register 3, which was set before
evaluating the part offset expression, then used in the %set/av of the
array value. (likewise for idx[1] and idx[3]])
To avoid this issue, this patch adds and uses a new instruction
%ix/mov which simply copies one indexed register to another. When
necessary, expressions are first evaluated into temporary registers to
avoid clobbering, then moved in to place before the %*/av instruction.
Implements page 644 of IEEE 1800-2012.
`` is now overloaded with the Icarus-specific "stringify" expansions.
It is now used as indicated in 1800-2012 when appearing inside a macro
definition, and the Icarus way when not. To do so, it uses the fact
that istack->file is NULL iff we are processing expanded macro text,
which is a bit of hack but works as is.
`" and `\`" on the other hand are treated the same inside and outside
of macro definitions.
When a fork/join contains a task, the task completion may become
confused with the completion of another thread if any of the
threads are embedded in the main thread. So always create threads
for all the fork paths, and joins to match.
In the ASIC universe, it is (probably) OK to replace a DFF CE
with a mux of the D input with the Q output. The idea is that
if the CE is true, the DFF latches D, but if CE is false, the DFF
re-latches the current output.
Martin Whitaker
Cary R
Jared Casper
Stephen Williams