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Get rid of dffsr2dff.

This pass is a proper subset of opt_rmdff, which is called by opt, which
is called by every synth flow in the coarse part.  Thus, it never
actually does anything and can be safely removed.
This commit is contained in:
Marcelina Kościelnicka 2020-04-11 18:36:51 +02:00
parent 85166633bc
commit 38a0c30d65
13 changed files with 2309 additions and 429 deletions

View file

@ -34,7 +34,6 @@ OBJS += passes/techmap/aigmap.o
OBJS += passes/techmap/tribuf.o
OBJS += passes/techmap/lut2mux.o
OBJS += passes/techmap/nlutmap.o
OBJS += passes/techmap/dffsr2dff.o
OBJS += passes/techmap/shregmap.o
OBJS += passes/techmap/deminout.o
OBJS += passes/techmap/insbuf.o

View file

@ -1,213 +0,0 @@
/*
* yosys -- Yosys Open SYnthesis Suite
*
* Copyright (C) 2012 Clifford Wolf <clifford@clifford.at>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
#include "kernel/yosys.h"
#include "kernel/sigtools.h"
USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN
void dffsr_worker(SigMap &sigmap, Module *module, Cell *cell)
{
if (cell->type == ID($dffsr))
{
int width = cell->getParam(ID::WIDTH).as_int();
bool setpol = cell->getParam(ID::SET_POLARITY).as_bool();
bool clrpol = cell->getParam(ID::CLR_POLARITY).as_bool();
SigBit setunused = setpol ? State::S0 : State::S1;
SigBit clrunused = clrpol ? State::S0 : State::S1;
SigSpec setsig = sigmap(cell->getPort(ID::SET));
SigSpec clrsig = sigmap(cell->getPort(ID::CLR));
Const reset_val;
SigSpec setctrl, clrctrl;
for (int i = 0; i < width; i++)
{
SigBit setbit = setsig[i], clrbit = clrsig[i];
if (setbit == setunused) {
clrctrl.append(clrbit);
reset_val.bits.push_back(State::S0);
continue;
}
if (clrbit == clrunused) {
setctrl.append(setbit);
reset_val.bits.push_back(State::S1);
continue;
}
return;
}
setctrl.sort_and_unify();
clrctrl.sort_and_unify();
if (GetSize(setctrl) > 1 || GetSize(clrctrl) > 1)
return;
if (GetSize(setctrl) == 0 && GetSize(clrctrl) == 0)
return;
if (GetSize(setctrl) == 1 && GetSize(clrctrl) == 1) {
if (setpol != clrpol)
return;
if (setctrl != clrctrl)
return;
}
log("Converting %s cell %s.%s to $adff.\n", log_id(cell->type), log_id(module), log_id(cell));
if (GetSize(setctrl) == 1) {
cell->setPort(ID::ARST, setctrl);
cell->setParam(ID::ARST_POLARITY, setpol);
} else {
cell->setPort(ID::ARST, clrctrl);
cell->setParam(ID::ARST_POLARITY, clrpol);
}
cell->type = ID($adff);
cell->unsetPort(ID::SET);
cell->unsetPort(ID::CLR);
cell->setParam(ID::ARST_VALUE, reset_val);
cell->unsetParam(ID::SET_POLARITY);
cell->unsetParam(ID::CLR_POLARITY);
return;
}
if (cell->type.in(ID($_DFFSR_NNN_), ID($_DFFSR_NNP_), ID($_DFFSR_NPN_), ID($_DFFSR_NPP_),
ID($_DFFSR_PNN_), ID($_DFFSR_PNP_), ID($_DFFSR_PPN_), ID($_DFFSR_PPP_)))
{
char clkpol = cell->type.c_str()[8];
char setpol = cell->type.c_str()[9];
char clrpol = cell->type.c_str()[10];
SigBit setbit = sigmap(cell->getPort(ID::S));
SigBit clrbit = sigmap(cell->getPort(ID::R));
SigBit setunused = setpol == 'P' ? State::S0 : State::S1;
SigBit clrunused = clrpol == 'P' ? State::S0 : State::S1;
IdString oldtype = cell->type;
if (setbit == setunused) {
cell->type = stringf("$_DFF_%c%c0_", clkpol, clrpol);
cell->unsetPort(ID::S);
goto converted_gate;
}
if (clrbit == clrunused) {
cell->type = stringf("$_DFF_%c%c1_", clkpol, setpol);
cell->setPort(ID::R, cell->getPort(ID::S));
cell->unsetPort(ID::S);
goto converted_gate;
}
return;
converted_gate:
log("Converting %s cell %s.%s to %s.\n", log_id(oldtype), log_id(module), log_id(cell), log_id(cell->type));
return;
}
}
void adff_worker(SigMap &sigmap, Module *module, Cell *cell)
{
if (cell->type == ID($adff))
{
bool rstpol = cell->getParam(ID::ARST_POLARITY).as_bool();
SigBit rstunused = rstpol ? State::S0 : State::S1;
SigSpec rstsig = sigmap(cell->getPort(ID::ARST));
if (rstsig != rstunused)
return;
log("Converting %s cell %s.%s to $dff.\n", log_id(cell->type), log_id(module), log_id(cell));
cell->type = ID($dff);
cell->unsetPort(ID::ARST);
cell->unsetParam(ID::ARST_VALUE);
cell->unsetParam(ID::ARST_POLARITY);
return;
}
if (cell->type.in(ID($_DFF_NN0_), ID($_DFF_NN1_), ID($_DFF_NP0_), ID($_DFF_NP1_),
ID($_DFF_PN0_), ID($_DFF_PN1_), ID($_DFF_PP0_), ID($_DFF_PP1_)))
{
char clkpol = cell->type.c_str()[6];
char rstpol = cell->type.c_str()[7];
SigBit rstbit = sigmap(cell->getPort(ID::R));
SigBit rstunused = rstpol == 'P' ? State::S0 : State::S1;
if (rstbit != rstunused)
return;
IdString newtype = stringf("$_DFF_%c_", clkpol);
log("Converting %s cell %s.%s to %s.\n", log_id(cell->type), log_id(module), log_id(cell), log_id(newtype));
cell->type = newtype;
cell->unsetPort(ID::R);
return;
}
}
struct Dffsr2dffPass : public Pass {
Dffsr2dffPass() : Pass("dffsr2dff", "convert DFFSR cells to simpler FF cell types") { }
void help() YS_OVERRIDE
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
log(" dffsr2dff [options] [selection]\n");
log("\n");
log("This pass converts DFFSR cells ($dffsr, $_DFFSR_???_) and ADFF cells ($adff,\n");
log("$_DFF_???_) to simpler FF cell types when any of the set/reset inputs is unused.\n");
log("\n");
}
void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
{
log_header(design, "Executing DFFSR2DFF pass (mapping DFFSR cells to simpler FFs).\n");
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++)
{
// if (args[argidx] == "-v") {
// continue;
// }
break;
}
extra_args(args, argidx, design);
for (auto module : design->selected_modules()) {
SigMap sigmap(module);
for (auto cell : module->selected_cells()) {
dffsr_worker(sigmap, module, cell);
adff_worker(sigmap, module, cell);
}
}
}
} Dffsr2dffPass;
PRIVATE_NAMESPACE_END