abstract: Allow unconditional value and state abstractions

Also improves -enable and -enablen command line handling
This commit is contained in:
Jannis Harder 2025-02-12 15:45:47 +01:00
parent 7f55244340
commit 3c5ff23e1e
1 changed files with 39 additions and 15 deletions

View File

@ -8,12 +8,15 @@ USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN
struct EnableLogic {
Wire* wire;
SigBit bit;
bool pol;
};
void emit_mux_anyseq(Module* mod, const SigSpec& mux_input, const SigSpec& mux_output, EnableLogic enable) {
auto anyseq = mod->Anyseq(NEW_ID, mux_input.size());
if (enable.bit == (enable.pol ? State::S1 : State::S0)) {
mod->connect(mux_output, anyseq);
}
SigSpec mux_a, mux_b;
if (enable.pol) {
mux_a = mux_input;
@ -25,7 +28,7 @@ void emit_mux_anyseq(Module* mod, const SigSpec& mux_input, const SigSpec& mux_o
(void)mod->addMux(NEW_ID,
mux_a,
mux_b,
enable.wire,
enable.bit,
mux_output);
}
@ -201,9 +204,14 @@ struct AbstractPass : public Pass {
Initial,
Value,
};
Mode mode;
Mode mode = Mode::None;
enum Enable {
Always = -1,
ActiveLow = false, // ensuring we can use bool(enable)
ActiveHigh = true,
};
Enable enable = Enable::Always;
std::string enable_name;
bool enable_pol; // true is high
for (argidx = 1; argidx < args.size(); argidx++)
{
std::string arg = args[argidx];
@ -219,33 +227,49 @@ struct AbstractPass : public Pass {
mode = Value;
continue;
}
if (arg == "-enable") {
if (arg == "-enable" && argidx + 1 < args.size()) {
if (enable != Enable::Always)
log_cmd_error("Multiple enable condition are not supported\n");
enable_name = args[++argidx];
enable_pol = true;
enable = Enable::ActiveHigh;
continue;
}
if (arg == "-enablen") {
if (arg == "-enablen" && argidx + 1 < args.size()) {
if (enable != Enable::Always)
log_cmd_error("Multiple enable condition are not supported\n");
enable_name = args[++argidx];
enable_pol = false;
enable = Enable::ActiveLow;
continue;
}
break;
}
extra_args(args, argidx, design);
if (enable != Enable::Always) {
if (mode == Mode::Initial)
log_cmd_error("Conditional initial value abstraction is not supported\n");
if (enable_name.empty())
log_cmd_error("Unspecified enable wire\n");
}
unsigned int changed = 0;
if ((mode == State) || (mode == Value)) {
if (!enable_name.length())
log_cmd_error("Unspecified enable wire\n");
for (auto mod : design->selected_modules()) {
EnableLogic enable_logic = { State::S1, true };
if (enable != Enable::Always) {
Wire *enable_wire = mod->wire("\\" + enable_name);
if (!enable_wire)
log_cmd_error("Enable wire %s not found in module %s\n", enable_name.c_str(), mod->name.c_str());
if (GetSize(enable_wire) != 1)
log_cmd_error("Enable wire %s must have width 1 but has width %d in module %s\n",
enable_name.c_str(), GetSize(enable_wire), mod->name.c_str());
enable_logic = { enable_wire, enable == Enable::ActiveHigh };
}
if (mode == State)
changed += abstract_state(mod, {enable_wire, enable_pol});
changed += abstract_state(mod, enable_logic);
else
changed += abstract_value(mod, {enable_wire, enable_pol});
changed += abstract_value(mod, enable_logic);
}
if (mode == State)
log("Abstracted %d stateful cells.\n", changed);