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Gate behind flag.

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nella 2026-05-20 15:51:04 +02:00 • committed by nella
parent c6bf13bb94
commit bbec8d2902
1 changed files with 13 additions and 1 deletions
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14
passes/opt/opt_dff.cc
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@ -41,6 +41,7 @@ struct OptDffOptions
bool simple_dffe; bool simple_dffe;
bool sat; bool sat;
bool keepdc; bool keepdc;
bool eqbits;
}; };
struct OptDffWorker struct OptDffWorker
@ -977,6 +978,10 @@ struct OptDffWorker
bool run_eqbits() bool run_eqbits()
{ {
if(!opt.eqbits) {
return false;
}
std::vector<EqBit> bits; std::vector<EqBit> bits;
std::vector<SigKey> keys; std::vector<SigKey> keys;
dict<Cell*, FfData> ff_for_cell; dict<Cell*, FfData> ff_for_cell;
@ -1253,6 +1258,11 @@ struct OptDffPass : public Pass {
log(" all result bits to be set to x. this behavior changes when 'a+0' is\n"); log(" all result bits to be set to x. this behavior changes when 'a+0' is\n");
log(" replaced by 'a'. the -keepdc option disables all such optimizations.\n"); log(" replaced by 'a'. the -keepdc option disables all such optimizations.\n");
log("\n"); log("\n");
log(" -eqbits\n");
log(" finds groups of flip flop bits provably holding always-equal values\n");
log(" across cycles and collapses each group to a single bit, potentially\n");
log(" reducing the number of required flip flops.\n");
log("\n");
} }
void execute(std::vector<std::string> args, RTLIL::Design *design) override void execute(std::vector<std::string> args, RTLIL::Design *design) override
@ -1265,6 +1275,7 @@ struct OptDffPass : public Pass {
opt.simple_dffe = false; opt.simple_dffe = false;
opt.keepdc = false; opt.keepdc = false;
opt.sat = false; opt.sat = false;
opt.eqbits = false;
size_t argidx; size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++) { for (argidx = 1; argidx < args.size(); argidx++) {
@ -1273,6 +1284,7 @@ struct OptDffPass : public Pass {
if (args[argidx] == "-simple-dffe") { opt.simple_dffe = true; continue; } if (args[argidx] == "-simple-dffe") { opt.simple_dffe = true; continue; }
if (args[argidx] == "-keepdc") { opt.keepdc = true; continue; } if (args[argidx] == "-keepdc") { opt.keepdc = true; continue; }
if (args[argidx] == "-sat") { opt.sat = true; continue; } if (args[argidx] == "-sat") { opt.sat = true; continue; }
if (args[argidx] == "-eqbits") { opt.eqbits = true; continue; }
break; break;
} }
extra_args(args, argidx, design); extra_args(args, argidx, design);
@ -1284,7 +1296,7 @@ struct OptDffPass : public Pass {
did_something = true; did_something = true;
if (worker.run_constbits()) if (worker.run_constbits())
did_something = true; did_something = true;
if (opt.sat && worker.run_eqbits()) if (worker.run_eqbits())
did_something = true; did_something = true;
} }