@c "cmd/why-not.texi"
@c extracted from "../../src/sim/prsim/Command-prsim.cc"
@c by "$(top_srcdir)/scripts/extract_texinfo.awk".

@deffn Command why-not node [val]
@deffnx Command why-not-verbose node [val]
@deffnx Command why-not-1 node [val]
@deffnx Command why-not-1-verbose node [val]
@deffnx Command why-not-N node maxdepth [val]
@deffnx Command why-not-N-verbose node maxdepth [val]
Print reason for node not being a given value, 0 or 1.
X is not a valid value for this procedure.  
If @var{val} is not given, it is assumed to be opposite of the
current value of the node.  
"Why isn't this node changing?"
The algorithm examines each node's fanins and follows
nodes that prevent the relevant expression from evaluating true.  
This is an excellent tool for debugging deadlocks.  
The verbose variant prints expression types as it auto-indents, 
which is more informative but may appear more cluttered.  
The @option{-1} variant only queries through depth 1, 
and the @option{-N} variant queries to a maximum depth of @var{maxdepth}.  
@end deffn

