iverilog/tgt-vvp
Cary R 059068f070 Ignore zero replication constants.
This patch enhances elaboration to drop/ignore zero replication
count constants. Not doing this was causing problems later in
the compiler. We still pass non-constant expressions since
both user and system functions must be run for their possible
side effects. Constants can never have a side effect so just
dropping them is acceptable.
(cherry picked from commit 9a94d55738)
2010-03-22 18:11:58 -07:00
..
Makefile.in Add explicit dependencies on generated header files. 2009-12-04 15:20:03 -08:00
README.txt tgt-vvp generates code that skips nets as inputs. 2001-08-10 00:40:45 +00:00
draw_mux.c Fix delays in continuous assignment to support 64bit delays. 2009-12-01 10:21:57 -08:00
draw_net_input.c Add appropriate hysteresis to tranif input pins. 2009-10-28 16:32:40 -07:00
draw_switch.c Content-free portability fixes. 2008-09-29 18:06:47 -07:00
draw_ufunc.c Function arg. expressions need to use the expr. width and arg. width. 2009-12-25 11:33:12 -05:00
draw_vpi.c Fix some MinGW compile warnings. 2010-02-02 21:00:56 -08:00
eval_bool.c Add support for 64 bit delays in procedural non-blocking assignments. 2009-02-17 10:32:11 -08:00
eval_expr.c Ignore zero replication constants. 2010-03-22 18:11:58 -07:00
eval_real.c Add warning about casting large integer values to reals. 2009-12-25 17:53:08 -05:00
modpath.c Content-free portability fixes. 2008-09-29 18:06:47 -07:00
vector.c Remove most of the lingering CVS droppings. 2008-12-05 21:48:28 -08:00
vvp-s.conf.in Remove redundant back-end selections. 2008-09-07 16:43:54 -07:00
vvp.c Unify the version stamp in the version_*.h header files. 2009-11-27 12:37:11 -08:00
vvp.conf.in Remove redundant back-end selections. 2008-09-07 16:43:54 -07:00
vvp_config.h.in Remove most of the lingering CVS droppings. 2008-12-05 21:48:28 -08:00
vvp_priv.h Some compiler cleanup and minor memory leak fixes. 2009-06-23 09:14:03 -07:00
vvp_process.c Add scope information for named blocks (begin/fork). 2010-03-22 18:07:54 -07:00
vvp_scope.c Fix space issues. 2010-03-22 18:10:50 -07:00

README.txt

THE VVP TARGET

SYMBOL NAME CONVENTIONS

There are some naming conventions that the vp target uses for
generating symbol names.

* wires and regs

Nets and variables are named V_<full-name> where <full-name> is the
full hierarchical name of the signal.

* Logic devices

Logic devices (and, or, buf, bufz, etc.) are named L_<full_name>. In
this case the symbol is attached to a functor that is the output of
the logic device.


GENERAL FUNCTOR WEB STRUCTURE

The net of gates, signals and resolvers is formed from the input
design. The basic structure is wrapped around the nexus, which is
represented by the ivl_nexus_t.

Each nexus represents a resolved value. The input of the nexus is fed
by a single driver. If the nexus in the design has multiple drivers,
the drivers are first fed into a resolver (or a tree of resolvers) to
form a single output that is the nexus.

The nexus, then, feeds its output to the inputs of other gates, or to
the .net objects in the design.