mirrors/yosys
3
0
Fork 0
mirror of https://github.com/YosysHQ/yosys synced 2025-06-06 14:13:23 +00:00
Code Activity

Improve opt_expr and opt_clean handling of (partially) undriven and/or unused wires, fixes #981

Browse source 
Signed-off-by: Clifford Wolf <clifford@clifford.at>
This commit is contained in:
Clifford Wolf 2019-05-03 14:24:53 +02:00
parent 98925f6c4b
commit 42190207b4
2 changed files with 83 additions and 46 deletions
Download patch file Download diff file Expand all files Collapse all files

13
passes/opt/opt_expr.cc
View file

@ -61,7 +61,7 @@ void replace_undriven(RTLIL::Design *design, RTLIL::Module *module)
}
if (wire->port_input)
driven_signals.add(sigmap(wire));
if (wire->port_output)
if (wire->port_output || wire->get_bool_attribute("\\keep"))
used_signals.add(sigmap(wire));
all_signals.add(sigmap(wire));
}
@ -88,7 +88,7 @@ void replace_undriven(RTLIL::Design *design, RTLIL::Module *module)
}
}
log_debug("Setting undriven signal in %s to constant: %s = %s\n", RTLIL::id2cstr(module->name), log_signal(sig), log_signal(val));
log_debug("Setting undriven signal in %s to constant: %s = %s\n", log_id(module), log_signal(sig), log_signal(val));
module->connect(sig, val);
did_something = true;
}
@ -104,10 +104,15 @@ void replace_undriven(RTLIL::Design *design, RTLIL::Module *module)
if (SigBit(initval[i]) == sig[i])
initval[i] = State::Sx;
}
if (initval.is_fully_undef())
if (initval.is_fully_undef()) {
log_debug("Removing init attribute from %s/%s.\n", log_id(module), log_id(wire));
wire->attributes.erase("\\init");
else
did_something = true;
} else if (initval != wire->attributes.at("\\init")) {
log_debug("Updating init attribute on %s/%s: %s\n", log_id(module), log_id(wire), log_signal(initval));
wire->attributes["\\init"] = initval;
did_something = true;
}
}
}
}