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opt_rmdff to work on $dffe and $_DFFE_*

This commit is contained in:
Eddie Hung 2019-05-23 11:26:18 -07:00
parent ca46947354
commit 50ed34a6d0
1 changed files with 32 additions and 3 deletions
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35
passes/opt/opt_rmdff.cc
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@ -260,8 +260,8 @@ delete_dlatch:
bool handle_dff(RTLIL::Module *mod, RTLIL::Cell *dff)
{
RTLIL::SigSpec sig_d, sig_q, sig_c, sig_r;
RTLIL::Const val_cp, val_rp, val_rv;
RTLIL::SigSpec sig_d, sig_q, sig_c, sig_r, sig_e;
RTLIL::Const val_cp, val_rp, val_rv, val_ep;
if (dff->type == "$_FF_") {
sig_d = dff->getPort("\\D");
@ -285,6 +285,16 @@ bool handle_dff(RTLIL::Module *mod, RTLIL::Cell *dff)
val_rp = RTLIL::Const(dff->type[7] == 'P', 1);
val_rv = RTLIL::Const(dff->type[8] == '1', 1);
}
else if (dff->type.substr(0,7) == "$_DFFE_" && dff->type.substr(9) == "_" &&
(dff->type[7] == 'N' || dff->type[7] == 'P') &&
(dff->type[8] == 'N' || dff->type[8] == 'P')) {
sig_d = dff->getPort("\\D");
sig_q = dff->getPort("\\Q");
sig_c = dff->getPort("\\C");
sig_e = dff->getPort("\\E");
val_cp = RTLIL::Const(dff->type[6] == 'P', 1);
val_ep = RTLIL::Const(dff->type[7] == 'P', 1);
}
else if (dff->type == "$ff") {
sig_d = dff->getPort("\\D");
sig_q = dff->getPort("\\Q");
@ -295,6 +305,14 @@ bool handle_dff(RTLIL::Module *mod, RTLIL::Cell *dff)
sig_c = dff->getPort("\\CLK");
val_cp = RTLIL::Const(dff->parameters["\\CLK_POLARITY"].as_bool(), 1);
}
else if (dff->type == "$dffe") {
sig_e = dff->getPort("\\EN");
sig_d = dff->getPort("\\D");
sig_q = dff->getPort("\\Q");
sig_c = dff->getPort("\\CLK");
val_cp = RTLIL::Const(dff->parameters["\\CLK_POLARITY"].as_bool(), 1);
val_ep = RTLIL::Const(dff->parameters["\\EN_POLARITY"].as_bool(), 1);
}
else if (dff->type == "$adff") {
sig_d = dff->getPort("\\D");
sig_q = dff->getPort("\\Q");
@ -320,6 +338,16 @@ bool handle_dff(RTLIL::Module *mod, RTLIL::Cell *dff)
val_init.bits.push_back(bit.wire == NULL ? bit.data : RTLIL::State::Sx);
}
if (sig_e.size()) {
if (!sig_e.is_fully_const())
return false;
if (sig_e != val_ep) {
if (has_init)
mod->connect(sig_q, val_init);
goto delete_dff;
}
}
if (dff->type.in("$ff", "$dff") && mux_drivers.has(sig_d)) {
std::set<RTLIL::Cell*> muxes;
mux_drivers.find(sig_d, muxes);
@ -489,7 +517,8 @@ struct OptRmdffPass : public Pass {
if (cell->type.in("$_FF_", "$_DFF_N_", "$_DFF_P_",
"$_DFF_NN0_", "$_DFF_NN1_", "$_DFF_NP0_", "$_DFF_NP1_",
"$_DFF_PN0_", "$_DFF_PN1_", "$_DFF_PP0_", "$_DFF_PP1_",
"$ff", "$dff", "$adff"))
"$_DFFE_NN_", "$_DFFE_NP_", "$_DFFE_PN_", "$_DFFE_PP_",
"$ff", "$dff", "$dffe", "$adff"))
dff_list.push_back(cell->name);
if (cell->type.in("$dlatch", "$_DLATCH_P_", "$_DLATCH_N_"))