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| author | Clifford Wolf <clifford@clifford.at> | 2014-08-14 11:22:45 +0200 |
|---|---|---|
| committer | Clifford Wolf <clifford@clifford.at> | 2014-08-14 11:22:45 +0200 |
| commit | 28cf48e31f049f8343023de46cd916ac47fcfc5d (patch) | |
| tree | a9f23f5705ab78e95a5f03cd55430942beae6862 /passes/fsm/fsm_recode.cc | |
| parent | 996c06f64dcb1619584c88d101c5ba258b2b26af (diff) | |
| download | yosys-28cf48e31f049f8343023de46cd916ac47fcfc5d.tar.gz yosys-28cf48e31f049f8343023de46cd916ac47fcfc5d.tar.bz2 yosys-28cf48e31f049f8343023de46cd916ac47fcfc5d.zip | |
Some improvements in FSM mapping and recoding
Diffstat (limited to 'passes/fsm/fsm_recode.cc')
| -rw-r--r-- | passes/fsm/fsm_recode.cc | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/passes/fsm/fsm_recode.cc b/passes/fsm/fsm_recode.cc index 40fed130e..9c0da0a37 100644 --- a/passes/fsm/fsm_recode.cc +++ b/passes/fsm/fsm_recode.cc @@ -53,10 +53,10 @@ static void fsm_recode(RTLIL::Cell *cell, RTLIL::Module *module, FILE *fm_set_fs std::string encoding = cell->attributes.count("\\fsm_encoding") ? cell->attributes.at("\\fsm_encoding").decode_string() : "auto"; log("Recoding FSM `%s' from module `%s' using `%s' encoding:\n", cell->name.c_str(), module->name.c_str(), encoding.c_str()); - if (encoding != "none" && encoding != "one-hot" && encoding != "binary") { - if (encoding != "auto") - log(" unkown encoding `%s': using auto (%s) instead.\n", encoding.c_str(), default_encoding.c_str()); - encoding = default_encoding; + + if (encoding != "none" && encoding != "one-hot" && encoding != "binary" && encoding != "auto") { + log(" unkown encoding `%s': using auto instead.\n", encoding.c_str()); + encoding = "auto"; } if (encoding == "none") { @@ -70,10 +70,18 @@ static void fsm_recode(RTLIL::Cell *cell, RTLIL::Module *module, FILE *fm_set_fs if (fm_set_fsm_file != NULL) fm_set_fsm_print(cell, module, fsm_data, "r", fm_set_fsm_file); + if (encoding == "auto") { + if (!default_encoding.empty()) + encoding = default_encoding; + else + encoding = SIZE(fsm_data.state_table) < 32 ? "one-hot" : "binary"; + log(" mapping auto encoding to `%s` for this FSM.\n", encoding.c_str()); + } + if (encoding == "one-hot") { fsm_data.state_bits = fsm_data.state_table.size(); } else - if (encoding == "auto" || encoding == "binary") { + if (encoding == "binary") { fsm_data.state_bits = ceil(log2(fsm_data.state_table.size())); } else log_error("FSM encoding `%s' is not supported!\n", encoding.c_str()); @@ -88,7 +96,7 @@ static void fsm_recode(RTLIL::Cell *cell, RTLIL::Module *module, FILE *fm_set_fs new_code = RTLIL::Const(RTLIL::State::Sa, fsm_data.state_bits); new_code.bits[state_idx] = RTLIL::State::S1; } else - if (encoding == "auto" || encoding == "binary") { + if (encoding == "binary") { new_code = RTLIL::Const(state_idx, fsm_data.state_bits); } else log_abort(); @@ -124,7 +132,7 @@ struct FsmRecodePass : public Pass { virtual void execute(std::vector<std::string> args, RTLIL::Design *design) { FILE *fm_set_fsm_file = NULL; - std::string default_encoding = "one-hot"; + std::string default_encoding; log_header("Executing FSM_RECODE pass (re-assigning FSM state encoding).\n"); size_t argidx; |