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yosys/passes/techmap/dfflegalize.cc

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/*
* yosys -- Yosys Open SYnthesis Suite
*
* Copyright (C) 2020 Marcelina Kościelnicka <mwk@0x04.net>
*
* 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"
#include "kernel/ffinit.h"
USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN
enum FfType {
FF_DFF,
FF_DFFE,
FF_ADFF0,
FF_ADFF1,
FF_ADFFE0,
FF_ADFFE1,
FF_DFFSR,
FF_DFFSRE,
FF_SDFF0,
FF_SDFF1,
FF_SDFFE0,
FF_SDFFE1,
FF_SDFFCE0,
FF_SDFFCE1,
FF_SR,
FF_DLATCH,
FF_ADLATCH0,
FF_ADLATCH1,
FF_DLATCHSR,
NUM_FFTYPES,
};
enum FfNeg {
NEG_R = 0x1,
NEG_S = 0x2,
NEG_E = 0x4,
NEG_C = 0x8,
NUM_NEG = 0x10,
};
enum FfInit {
INIT_X = 0x1,
INIT_0 = 0x2,
INIT_1 = 0x4,
};
struct DffLegalizePass : public Pass {
DffLegalizePass() : Pass("dfflegalize", "convert FFs to types supported by the target") { }
void help() override
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
log(" dfflegalize [options] [selection]\n");
log("\n");
log("Converts FFs to types supported by the target.\n");
log("\n");
log(" -cell <cell_type_pattern> <init_values>\n");
log(" specifies a supported group of FF cells. <cell_type_pattern>\n");
log(" is a yosys internal fine cell name, where ? characters can be\n");
log(" as a wildcard matching any character. <init_values> specifies\n");
log(" which initialization values these FF cells can support, and can\n");
log(" be one of:\n");
log("\n");
log(" - x (no init value supported)\n");
log(" - 0\n");
log(" - 1\n");
log(" - r (init value has to match reset value, only for some FF types)\n");
log(" - 01 (both 0 and 1 supported).\n");
log("\n");
log(" -mince <num>\n");
log(" specifies a minimum number of FFs that should be using any given\n");
log(" clock enable signal. If a clock enable signal doesn't meet this\n");
log(" threshold, it is unmapped into soft logic.\n");
log("\n");
log(" -minsrst <num>\n");
log(" specifies a minimum number of FFs that should be using any given\n");
log(" sync set/reset signal. If a sync set/reset signal doesn't meet this\n");
log(" threshold, it is unmapped into soft logic.\n");
log("\n");
log("The following cells are supported by this pass (ie. will be ingested,\n");
log("and can be specified as allowed targets):\n");
log("\n");
log("- $_DFF_[NP]_\n");
log("- $_DFFE_[NP][NP]_\n");
log("- $_DFF_[NP][NP][01]_\n");
log("- $_DFFE_[NP][NP][01][NP]_\n");
log("- $_DFFSR_[NP][NP][NP]_\n");
log("- $_DFFSRE_[NP][NP][NP][NP]_\n");
log("- $_SDFF_[NP][NP][01]_\n");
log("- $_SDFFE_[NP][NP][01][NP]_\n");
log("- $_SDFFCE_[NP][NP][01][NP]_\n");
log("- $_SR_[NP][NP]_\n");
log("- $_DLATCH_[NP]_\n");
log("- $_DLATCH_[NP][NP][01]_\n");
log("- $_DLATCHSR_[NP][NP][NP]_\n");
log("\n");
log("The following transformations are performed by this pass:");
log("\n");
log("- upconversion from a less capable cell to a more capable cell, if the less");
log(" capable cell is not supported (eg. dff -> dffe, or adff -> dffsr)");
log("\n");
log("- unmapping FFs with clock enable (due to unsupported cell type or -mince)");
log("\n");
log("- unmapping FFs with sync reset (due to unsupported cell type or -minsrst)");
log("\n");
log("- adding inverters on the control pins (due to unsupported polarity)");
log("\n");
log("- adding inverters on the D and Q pins and inverting the init/reset values\n");
log(" (due to unsupported init or reset value)");
log("\n");
log("- converting sr into adlatch (by tying D to 1 and using E as set input)");
log("\n");
log("- emulating unsupported dffsr cell by adff + adff + sr + mux");
log("\n");
log("- emulating unsupported dlatchsr cell by adlatch + adlatch + sr + mux");
log("\n");
log("- emulating adff when the (reset, init) value combination is unsupported by\n");
log(" dff + adff + dlatch + mux");
log("\n");
log("- emulating adlatch when the (reset, init) value combination is unsupported by\n");
log("- dlatch + adlatch + dlatch + mux");
log("\n");
log("If the pass is unable to realize a given cell type (eg. adff when only plain dff");
log("is available), an error is raised.");
}
// Table of all supported cell types.
// First index in the array is one of the FF_* values, second
// index is the set of negative-polarity inputs (OR of NEG_*
// values), and the value is the set of supported init values
// (OR of INIT_* values).
int supported_cells_neg[NUM_FFTYPES][NUM_NEG];
// Aggregated table ignoring signal polarity.
int supported_cells[NUM_FFTYPES];
// Aggregated for all *dff* cells.
int supported_dff;
// Aggregated for all dffsr* cells.
int supported_dffsr;
// Aggregated for all adff* cells.
int supported_adff0;
int supported_adff1;
// Aggregated for all sdff* cells.
int supported_sdff0;
int supported_sdff1;
// Aggregated for all ways to obtain a SR latch.
int supported_sr;
// Aggregated for all *dlatch* cells.
int supported_dlatch;
int mince;
int minsrst;
dict<SigBit, int> ce_used;
dict<SigBit, int> srst_used;
SigMap sigmap;
FfInitVals initvals;
int flip_initmask(int mask) {
int res = mask & INIT_X;
if (mask & INIT_0)
res |= INIT_1;
if (mask & INIT_1)
res |= INIT_0;
return res;
}
void handle_ff(Cell *cell) {
std::string type_str = cell->type.str();
FfType ff_type;
int ff_neg = 0;
SigSpec sig_d;
SigSpec sig_q;
SigSpec sig_c;
SigSpec sig_e;
SigSpec sig_r;
SigSpec sig_s;
bool has_srst = false;
if (cell->hasPort(ID::D))
sig_d = cell->getPort(ID::D);
if (cell->hasPort(ID::Q))
sig_q = cell->getPort(ID::Q);
if (cell->hasPort(ID::C))
sig_c = cell->getPort(ID::C);
if (cell->hasPort(ID::E))
sig_e = cell->getPort(ID::E);
if (cell->hasPort(ID::R))
sig_r = cell->getPort(ID::R);
if (cell->hasPort(ID::S))
sig_s = cell->getPort(ID::S);
if (type_str.substr(0, 5) == "$_SR_") {
ff_type = FF_SR;
if (type_str[5] == 'N')
ff_neg |= NEG_S;
if (type_str[6] == 'N')
ff_neg |= NEG_R;
} else if (type_str.substr(0, 6) == "$_DFF_" && type_str.size() == 8) {
ff_type = FF_DFF;
if (type_str[6] == 'N')
ff_neg |= NEG_C;
} else if (type_str.substr(0, 7) == "$_DFFE_" && type_str.size() == 10) {
ff_type = FF_DFFE;
if (type_str[7] == 'N')
ff_neg |= NEG_C;
if (type_str[8] == 'N')
ff_neg |= NEG_E;
} else if (type_str.substr(0, 6) == "$_DFF_" && type_str.size() == 10) {
ff_type = type_str[8] == '1' ? FF_ADFF1 : FF_ADFF0;
if (type_str[6] == 'N')
ff_neg |= NEG_C;
if (type_str[7] == 'N')
ff_neg |= NEG_R;
} else if (type_str.substr(0, 7) == "$_DFFE_" && type_str.size() == 12) {
ff_type = type_str[9] == '1' ? FF_ADFFE1 : FF_ADFFE0;
if (type_str[7] == 'N')
ff_neg |= NEG_C;
if (type_str[8] == 'N')
ff_neg |= NEG_R;
if (type_str[10] == 'N')
ff_neg |= NEG_E;
} else if (type_str.substr(0, 8) == "$_DFFSR_" && type_str.size() == 12) {
ff_type = FF_DFFSR;
if (type_str[8] == 'N')
ff_neg |= NEG_C;
if (type_str[9] == 'N')
ff_neg |= NEG_S;
if (type_str[10] == 'N')
ff_neg |= NEG_R;
} else if (type_str.substr(0, 9) == "$_DFFSRE_" && type_str.size() == 14) {
ff_type = FF_DFFSRE;
if (type_str[9] == 'N')
ff_neg |= NEG_C;
if (type_str[10] == 'N')
ff_neg |= NEG_S;
if (type_str[11] == 'N')
ff_neg |= NEG_R;
if (type_str[12] == 'N')
ff_neg |= NEG_E;
} else if (type_str.substr(0, 7) == "$_SDFF_" && type_str.size() == 11) {
ff_type = type_str[9] == '1' ? FF_SDFF1 : FF_SDFF0;
if (type_str[7] == 'N')
ff_neg |= NEG_C;
if (type_str[8] == 'N')
ff_neg |= NEG_R;
has_srst = true;
} else if (type_str.substr(0, 8) == "$_SDFFE_" && type_str.size() == 13) {
ff_type = type_str[10] == '1' ? FF_SDFFE1 : FF_SDFFE0;
if (type_str[8] == 'N')
ff_neg |= NEG_C;
if (type_str[9] == 'N')
ff_neg |= NEG_R;
if (type_str[11] == 'N')
ff_neg |= NEG_E;
has_srst = true;
} else if (type_str.substr(0, 9) == "$_SDFFCE_" && type_str.size() == 14) {
ff_type = type_str[11] == '1' ? FF_SDFFCE1 : FF_SDFFCE0;
if (type_str[9] == 'N')
ff_neg |= NEG_C;
if (type_str[10] == 'N')
ff_neg |= NEG_R;
if (type_str[12] == 'N')
ff_neg |= NEG_E;
has_srst = true;
} else if (type_str.substr(0, 9) == "$_DLATCH_" && type_str.size() == 11) {
ff_type = FF_DLATCH;
if (type_str[9] == 'N')
ff_neg |= NEG_E;
} else if (type_str.substr(0, 9) == "$_DLATCH_" && type_str.size() == 13) {
ff_type = type_str[11] == '1' ? FF_ADLATCH1 : FF_ADLATCH0;
if (type_str[9] == 'N')
ff_neg |= NEG_E;
if (type_str[10] == 'N')
ff_neg |= NEG_R;
} else if (type_str.substr(0, 11) == "$_DLATCHSR_" && type_str.size() == 15) {
ff_type = FF_DLATCHSR;
if (type_str[11] == 'N')
ff_neg |= NEG_E;
if (type_str[12] == 'N')
ff_neg |= NEG_S;
if (type_str[13] == 'N')
ff_neg |= NEG_R;
} else {
log_warning("Ignoring unknown ff type %s [%s.%s].\n", log_id(cell->type), log_id(cell->module->name), log_id(cell->name));
return;
}
State initval = initvals(sig_q[0]);
FfInit initmask = INIT_X;
if (initval == State::S0)
initmask = INIT_0;
else if (initval == State::S1)
initmask = INIT_1;
const char *reason;
bool kill_ce = mince && GetSize(sig_c) && GetSize(sig_e) && sig_e[0].wire && ce_used[sig_e[0]] < mince;
bool kill_srst = minsrst && has_srst && sig_r[0].wire && srst_used[sig_r[0]] < minsrst;
while (!(supported_cells[ff_type] & initmask) || kill_ce || kill_srst) {
// Well, cell is not directly supported. Decide how to deal with it.
if (ff_type == FF_DFF || ff_type == FF_DFFE) {
if (kill_ce) {
ff_type = FF_DFF;
goto unmap_enable;
}
if (!(supported_dff & initmask)) {
// This init value is not supported at all...
if (supported_dff & flip_initmask(initmask)) {
// The other one is, though. Negate D, Q, and init.
flip_dqi:
if (initval == State::S0) {
initval = State::S1;
initmask = INIT_1;
} else if (initval == State::S1) {
initval = State::S0;
initmask = INIT_0;
}
if (ff_type != FF_SR)
sig_d = cell->module->NotGate(NEW_ID, sig_d[0]);
SigBit new_q = SigSpec(cell->module->addWire(NEW_ID))[0];
cell->module->addNotGate(NEW_ID, new_q, sig_q[0]);
initvals.remove_init(sig_q[0]);
initvals.set_init(new_q, initval);
sig_q = new_q;
continue;
}
if (!supported_dff)
reason = "dffs are not supported";
else
reason = "initialized dffs are not supported";
goto error;
}
// Some DFF is supported with this init val. Just pick a type.
if (ff_type == FF_DFF) {
// Try adding a set or reset pin.
for (auto new_type: {FF_SDFF0, FF_SDFF1, FF_ADFF0, FF_ADFF1})
if (supported_cells[new_type] & initmask) {
ff_type = new_type;
sig_r = State::S0;
goto cell_ok;
}
// Try adding both.
if (supported_cells[FF_DFFSR] & initmask) {
ff_type = FF_DFFSR;
sig_r = State::S0;
sig_s = State::S0;
break;
}
// Nope. Will need to add enable and go the DFFE route.
sig_e = State::S1;
if (supported_cells[FF_DFFE] & initmask) {
ff_type = FF_DFFE;
break;
}
}
// Try adding a set or reset pin.
for (auto new_type: {FF_SDFFE0, FF_SDFFE1, FF_SDFFCE0, FF_SDFFCE1, FF_ADFFE0, FF_ADFFE1})
if (supported_cells[new_type] & initmask) {
ff_type = new_type;
sig_r = State::S0;
goto cell_ok;
}
// Try adding both.
if (supported_cells[FF_DFFSRE] & initmask) {
ff_type = FF_DFFSRE;
sig_r = State::S0;
sig_s = State::S0;
break;
}
// Seems that no DFFs with enable are supported.
// The enable input needs to be unmapped.
// This should not be reached if we started from plain DFF.
log_assert(ff_type == FF_DFFE);
ff_type = FF_DFF;
unmap_enable:
if (ff_neg & NEG_E)
sig_d = cell->module->MuxGate(NEW_ID, sig_d[0], sig_q[0], sig_e[0]);
else
sig_d = cell->module->MuxGate(NEW_ID, sig_q[0], sig_d[0], sig_e[0]);
ff_neg &= ~NEG_E;
sig_e = SigSpec();
kill_ce = false;
// Now try again as plain DFF.
continue;
} else if (ff_type == FF_ADFF0 || ff_type == FF_ADFF1 || ff_type == FF_ADFFE0 || ff_type == FF_ADFFE1) {
bool has_set = ff_type == FF_ADFF1 || ff_type == FF_ADFFE1;
bool has_en = ff_type == FF_ADFFE0 || ff_type == FF_ADFFE1;
if (kill_ce) {
ff_type = has_set ? FF_ADFF1 : FF_ADFF0;
goto unmap_enable;
}
if (!has_en && (supported_cells[has_set ? FF_ADFFE1 : FF_ADFFE0] & initmask)) {
// Just add enable.
sig_e = State::S1;
ff_type = has_set ? FF_ADFFE1 : FF_ADFFE0;
break;
}
if (supported_dffsr & initmask) {
// Throw in a set/reset, retry in DFFSR/DFFSRE branch.
if (has_set) {
sig_s = sig_r;
sig_r = State::S0;
if (ff_neg & NEG_R) {
ff_neg &= ~NEG_R;
ff_neg |= NEG_S;
}
} else {
sig_s = State::S0;
}
if (has_en)
ff_type = FF_DFFSRE;
else
ff_type = FF_DFFSR;
continue;
}
if (has_en && (supported_cells[has_set ? FF_ADFF1 : FF_ADFF0] & initmask)) {
// Unmap enable.
ff_type = has_set ? FF_ADFF1 : FF_ADFF0;
goto unmap_enable;
}
log_assert(!((has_set ? supported_adff1 : supported_adff0) & initmask));
// Alright, so this particular combination of initval and
// resetval is not natively supported. First, try flipping
// them both to see whether this helps.
int flipmask = flip_initmask(initmask);
if ((has_set ? supported_adff0 : supported_adff1) & flipmask) {
// Checks out, do it.
ff_type = has_en ? (has_set ? FF_ADFFE0 : FF_ADFFE1) : (has_set ? FF_ADFF0 : FF_ADFF1);
goto flip_dqi;
}
if (!supported_adff0 && !supported_adff1) {
reason = "dffs with async set or reset are not supported";
goto error;
}
if (!(supported_dff & ~INIT_X)) {
reason = "initialized dffs are not supported";
goto error;
}
// If we got here, initialized dff is supported, but not this
// particular reset+init combination (nor its negation).
// The only hope left is breaking down to adff + dff + dlatch + mux.
if (!(supported_dlatch & ~INIT_X)) {
reason = "unsupported initial value and async reset value combination";
goto error;
}
// If we have to unmap enable anyway, do it before breakdown.
if (has_en && !supported_cells[FF_ADFFE0] && !supported_cells[FF_ADFFE1]) {
ff_type = has_set ? FF_ADFF1 : FF_ADFF0;
goto unmap_enable;
}
log_warning("Emulating mismatched async reset and init with several FFs and a mux for %s.%s\n", log_id(cell->module->name), log_id(cell->name));
initvals.remove_init(sig_q[0]);
Wire *adff_q = cell->module->addWire(NEW_ID);
Wire *dff_q = cell->module->addWire(NEW_ID);
Wire *sel_q = cell->module->addWire(NEW_ID);
initvals.set_init(SigBit(dff_q, 0), initval);
initvals.set_init(SigBit(sel_q, 0), State::S0);
Cell *cell_dff;
Cell *cell_adff;
Cell *cell_sel;
if (!has_en) {
cell_dff = cell->module->addDffGate(NEW_ID, sig_c, sig_d, dff_q, !(ff_neg & NEG_C));
cell_adff = cell->module->addAdffGate(NEW_ID, sig_c, sig_r, sig_d, adff_q, has_set, !(ff_neg & NEG_C), !(ff_neg & NEG_R));
} else {
cell_dff = cell->module->addDffeGate(NEW_ID, sig_c, sig_e, sig_d, dff_q, !(ff_neg & NEG_C), !(ff_neg & NEG_E));
cell_adff = cell->module->addAdffeGate(NEW_ID, sig_c, sig_e, sig_r, sig_d, adff_q, has_set, !(ff_neg & NEG_C), !(ff_neg & NEG_E), !(ff_neg & NEG_R));
}
cell_sel = cell->module->addDlatchGate(NEW_ID, sig_r, State::S1, sel_q, !(ff_neg & NEG_R));
cell->module->addMuxGate(NEW_ID, dff_q, adff_q, sel_q, sig_q);
// Bye, cell.
cell->module->remove(cell);
handle_ff(cell_dff);
handle_ff(cell_adff);
handle_ff(cell_sel);
return;
} else if (ff_type == FF_DFFSR || ff_type == FF_DFFSRE) {
if (kill_ce) {
ff_type = FF_DFFSR;
goto unmap_enable;
}
// First, see if mapping/unmapping enable will help.
if (supported_cells[FF_DFFSRE] & initmask) {
ff_type = FF_DFFSRE;
sig_e = State::S1;
break;
}
if (supported_cells[FF_DFFSR] & initmask) {
ff_type = FF_DFFSR;
goto unmap_enable;
}
if (supported_dffsr & flip_initmask(initmask)) {
flip_dqisr:;
log_warning("Flipping D/Q/init and inserting set/reset fixup to handle init value on %s.%s [%s]\n", log_id(cell->module->name), log_id(cell->name), log_id(cell->type));
SigSpec new_r;
bool neg_r = (ff_neg & NEG_R);
bool neg_s = (ff_neg & NEG_S);
if (!(ff_neg & NEG_S)) {
if (!(ff_neg & NEG_R))
new_r = cell->module->AndnotGate(NEW_ID, sig_s, sig_r);
else
new_r = cell->module->AndGate(NEW_ID, sig_s, sig_r);
} else {
if (!(ff_neg & NEG_R))
new_r = cell->module->OrGate(NEW_ID, sig_s, sig_r);
else
new_r = cell->module->OrnotGate(NEW_ID, sig_s, sig_r);
}
ff_neg &= ~(NEG_R | NEG_S);
if (neg_r)
ff_neg |= NEG_S;
if (neg_s)
ff_neg |= NEG_R;
sig_s = sig_r;
sig_r = new_r;
goto flip_dqi;
}
// No native DFFSR. However, if we can conjure
// a SR latch and ADFF, it can still be emulated.
int flipmask = flip_initmask(initmask);
bool init0 = true;
bool init1 = true;
State initsel = State::Sx;
if (((supported_adff0 & initmask) || (supported_adff1 & flipmask)) && ((supported_adff1 & initmask) || (supported_adff0 & flipmask)) && supported_sr) {
// OK
} else if (((supported_adff0 & initmask) || (supported_adff1 & flipmask)) && (supported_sr & INIT_0)) {
init1 = false;
initsel = State::S0;
} else if (((supported_adff1 & initmask) || (supported_adff0 & flipmask)) && (supported_sr & INIT_1)) {
init0 = false;
initsel = State::S1;
} else if (((supported_adff0 & initmask) || (supported_adff1 & flipmask)) && (supported_sr & INIT_1)) {
init1 = false;
initsel = State::S0;
} else if (((supported_adff1 & initmask) || (supported_adff0 & flipmask)) && (supported_sr & INIT_0)) {
init0 = false;
initsel = State::S1;
} else {
if (!supported_dffsr)
reason = "dffs with async set and reset are not supported";
else
reason = "initialized dffs with async set and reset are not supported";
goto error;
}
// If we have to unmap enable anyway, do it before breakdown.
if (ff_type == FF_DFFSRE && !supported_cells[FF_ADFFE0] && !supported_cells[FF_ADFFE1]) {
ff_type = FF_DFFSR;
goto unmap_enable;
}
log_warning("Emulating async set + reset with several FFs and a mux for %s.%s\n", log_id(cell->module->name), log_id(cell->name));
initvals.remove_init(sig_q[0]);
Wire *adff0_q = cell->module->addWire(NEW_ID);
Wire *adff1_q = cell->module->addWire(NEW_ID);
Wire *sel_q = cell->module->addWire(NEW_ID);
if (init0)
initvals.set_init(SigBit(adff0_q, 0), initval);
if (init1)
initvals.set_init(SigBit(adff1_q, 0), initval);
initvals.set_init(SigBit(sel_q, 0), initsel);
Cell *cell_adff0;
Cell *cell_adff1;
Cell *cell_sel;
if (ff_type == FF_DFFSR) {
cell_adff0 = cell->module->addAdffGate(NEW_ID, sig_c, sig_r, sig_d, adff0_q, false, !(ff_neg & NEG_C), !(ff_neg & NEG_R));
cell_adff1 = cell->module->addAdffGate(NEW_ID, sig_c, sig_s, sig_d, adff1_q, true, !(ff_neg & NEG_C), !(ff_neg & NEG_S));
} else {
cell_adff0 = cell->module->addAdffeGate(NEW_ID, sig_c, sig_e, sig_r, sig_d, adff0_q, false, !(ff_neg & NEG_C), !(ff_neg & NEG_E), !(ff_neg & NEG_R));
cell_adff1 = cell->module->addAdffeGate(NEW_ID, sig_c, sig_e, sig_s, sig_d, adff1_q, true, !(ff_neg & NEG_C), !(ff_neg & NEG_E), !(ff_neg & NEG_S));
}
cell_sel = cell->module->addSrGate(NEW_ID, sig_s, sig_r, sel_q, !(ff_neg & NEG_S), !(ff_neg & NEG_R));
cell->module->addMuxGate(NEW_ID, adff0_q, adff1_q, sel_q, sig_q);
// Bye, cell.
cell->module->remove(cell);
handle_ff(cell_adff0);
handle_ff(cell_adff1);
handle_ff(cell_sel);
return;
} else if (ff_type == FF_SR) {
if (supported_cells[FF_ADLATCH0] & initmask || supported_cells[FF_ADLATCH1] & flip_initmask(initmask)) {
// Convert to ADLATCH0. May get converted to ADLATCH1.
ff_type = FF_ADLATCH0;
sig_e = sig_s;
sig_d = State::S1;
if (ff_neg & NEG_S) {
ff_neg &= ~NEG_S;
ff_neg |= NEG_E;
}
continue;
} else if (supported_cells[FF_DLATCHSR] & initmask) {
// Upgrade to DLATCHSR.
ff_type = FF_DLATCHSR;
sig_e = State::S0;
sig_d = State::Sx;
break;
} else if (supported_dffsr & initmask) {
// Upgrade to DFFSR. May get further upgraded to DFFSRE.
ff_type = FF_DFFSR;
sig_c = State::S0;
sig_d = State::Sx;
continue;
} else if (supported_sr & flip_initmask(initmask)) {
goto flip_dqisr;
} else {
if (!supported_sr)
reason = "sr latches are not supported";
else
reason = "initialized sr latches are not supported";
goto error;
}
} else if (ff_type == FF_DLATCH) {
if (!(supported_dlatch & initmask)) {
// This init value is not supported at all...
if (supported_dlatch & flip_initmask(initmask))
goto flip_dqi;
if ((sig_d == State::S0 && (supported_adff0 & initmask)) ||
(sig_d == State::S1 && (supported_adff1 & initmask)) ||
(sig_d == State::S0 && (supported_adff1 & flip_initmask(initmask))) ||
(sig_d == State::S1 && (supported_adff0 & flip_initmask(initmask)))
) {
// Special case: const-D dlatch can be converted into adff with const clock.
ff_type = (sig_d == State::S0) ? FF_ADFF0 : FF_ADFF1;
if (ff_neg & NEG_E) {
ff_neg &= ~NEG_E;
ff_neg |= NEG_R;
}
sig_r = sig_e;
sig_d = State::Sx;
sig_c = State::S1;
continue;
}
if (!supported_dlatch)
reason = "dlatch are not supported";
else
reason = "initialized dlatch are not supported";
goto error;
}
// Some DLATCH is supported with this init val. Just pick a type.
if (supported_cells[FF_ADLATCH0] & initmask) {
ff_type = FF_ADLATCH0;
sig_r = State::S0;
break;
}
if (supported_cells[FF_ADLATCH1] & initmask) {
ff_type = FF_ADLATCH1;
sig_r = State::S0;
break;
}
if (supported_cells[FF_DLATCHSR] & initmask) {
ff_type = FF_DLATCHSR;
sig_r = State::S0;
sig_s = State::S0;
break;
}
log_assert(0);
} else if (ff_type == FF_ADLATCH0 || ff_type == FF_ADLATCH1) {
if (supported_cells[FF_DLATCHSR] & initmask) {
if (ff_type == FF_ADLATCH1) {
sig_s = sig_r;
sig_r = State::S0;
if (ff_neg & NEG_R) {
ff_neg &= ~NEG_R;
ff_neg |= NEG_S;
}
} else {
sig_s = State::S0;
}
ff_type = FF_DLATCHSR;
break;
}
FfType flip_type = ff_type == FF_ADLATCH0 ? FF_ADLATCH1 : FF_ADLATCH0;
if ((supported_cells[flip_type] | supported_cells[FF_DLATCHSR]) & flip_initmask(initmask)) {
ff_type = flip_type;
goto flip_dqi;
}
if (!supported_cells[FF_ADLATCH0] && !supported_cells[FF_ADLATCH1] && !supported_cells[FF_DLATCHSR]) {
reason = "dlatch with async set or reset are not supported";
goto error;
}
if (!(supported_dlatch & ~INIT_X)) {
reason = "initialized dlatch are not supported";
goto error;
}
if (!(supported_dlatch & ~INIT_X)) {
reason = "initialized dlatch are not supported";
goto error;
}
// If we got here, initialized dlatch is supported, but not this
// particular reset+init combination (nor its negation).
// The only hope left is breaking down to adff + dff + dlatch + mux.
log_warning("Emulating mismatched async reset and init with several latches and a mux for %s.%s\n", log_id(cell->module->name), log_id(cell->name));
initvals.remove_init(sig_q[0]);
Wire *adlatch_q = cell->module->addWire(NEW_ID);
Wire *dlatch_q = cell->module->addWire(NEW_ID);
Wire *sel_q = cell->module->addWire(NEW_ID);
initvals.set_init(SigBit(dlatch_q, 0), initval);
initvals.set_init(SigBit(sel_q, 0), State::S0);
Cell *cell_dlatch;
Cell *cell_adlatch;
Cell *cell_sel;
cell_dlatch = cell->module->addDlatchGate(NEW_ID, sig_e, sig_d, dlatch_q, !(ff_neg & NEG_E));
cell_adlatch = cell->module->addAdlatchGate(NEW_ID, sig_e, sig_r, sig_d, adlatch_q, ff_type == FF_ADLATCH1, !(ff_neg & NEG_E), !(ff_neg & NEG_R));
cell_sel = cell->module->addDlatchGate(NEW_ID, sig_r, State::S1, sel_q, !(ff_neg & NEG_R));
cell->module->addMuxGate(NEW_ID, dlatch_q, adlatch_q, sel_q, sig_q);
// Bye, cell.
cell->module->remove(cell);
handle_ff(cell_dlatch);
handle_ff(cell_adlatch);
handle_ff(cell_sel);
return;
} else if (ff_type == FF_DLATCHSR) {
if (supported_cells[FF_DLATCHSR] & flip_initmask(initmask)) {
goto flip_dqisr;
}
// No native DFFSR. However, if we can conjure
// a SR latch and ADFF, it can still be emulated.
int flipmask = flip_initmask(initmask);
bool init0 = true;
bool init1 = true;
State initsel = State::Sx;
if (((supported_cells[FF_ADLATCH0] & initmask) || (supported_cells[FF_ADLATCH1] & flipmask)) && ((supported_cells[FF_ADLATCH1] & initmask) || (supported_cells[FF_ADLATCH0] & flipmask)) && supported_sr) {
// OK
} else if (((supported_cells[FF_ADLATCH0] & initmask) || (supported_cells[FF_ADLATCH1] & flipmask)) && (supported_sr & INIT_0)) {
init1 = false;
initsel = State::S0;
} else if (((supported_cells[FF_ADLATCH1] & initmask) || (supported_cells[FF_ADLATCH0] & flipmask)) && (supported_sr & INIT_1)) {
init0 = false;
initsel = State::S1;
} else if (((supported_cells[FF_ADLATCH0] & initmask) || (supported_cells[FF_ADLATCH1] & flipmask)) && (supported_sr & INIT_1)) {
init1 = false;
initsel = State::S0;
} else if (((supported_cells[FF_ADLATCH1] & initmask) || (supported_cells[FF_ADLATCH0] & flipmask)) && (supported_sr & INIT_0)) {
init0 = false;
initsel = State::S1;
} else {
if (!supported_cells[FF_DLATCHSR])
reason = "dlatch with async set and reset are not supported";
else
reason = "initialized dlatch with async set and reset are not supported";
goto error;
}
log_warning("Emulating async set + reset with several latches and a mux for %s.%s\n", log_id(cell->module->name), log_id(cell->name));
initvals.remove_init(sig_q[0]);
Wire *adlatch0_q = cell->module->addWire(NEW_ID);
Wire *adlatch1_q = cell->module->addWire(NEW_ID);
Wire *sel_q = cell->module->addWire(NEW_ID);
if (init0)
initvals.set_init(SigBit(adlatch0_q, 0), initval);
if (init1)
initvals.set_init(SigBit(adlatch1_q, 0), initval);
initvals.set_init(SigBit(sel_q, 0), initsel);
Cell *cell_adlatch0;
Cell *cell_adlatch1;
Cell *cell_sel;
cell_adlatch0 = cell->module->addAdlatchGate(NEW_ID, sig_e, sig_r, sig_d, adlatch0_q, false, !(ff_neg & NEG_E), !(ff_neg & NEG_R));
cell_adlatch1 = cell->module->addAdlatchGate(NEW_ID, sig_e, sig_s, sig_d, adlatch1_q, true, !(ff_neg & NEG_E), !(ff_neg & NEG_S));
cell_sel = cell->module->addSrGate(NEW_ID, sig_s, sig_r, sel_q, !(ff_neg & NEG_S), !(ff_neg & NEG_R));
cell->module->addMuxGate(NEW_ID, adlatch0_q, adlatch1_q, sel_q, sig_q);
// Bye, cell.
cell->module->remove(cell);
handle_ff(cell_adlatch0);
handle_ff(cell_adlatch1);
handle_ff(cell_sel);
return;
} else if (ff_type == FF_SDFF0 || ff_type == FF_SDFF1 || ff_type == FF_SDFFE0 || ff_type == FF_SDFFE1 || ff_type == FF_SDFFCE0 || ff_type == FF_SDFFCE1) {
bool has_set = ff_type == FF_SDFF1 || ff_type == FF_SDFFE1 || ff_type == FF_SDFFCE1;
bool has_en = ff_type == FF_SDFFE0 || ff_type == FF_SDFFE1;
bool has_ce = ff_type == FF_SDFFCE0 || ff_type == FF_SDFFCE1;
if (has_en) {
if (kill_ce || kill_srst) {
ff_type = has_set ? FF_SDFF1 : FF_SDFF0;
goto unmap_enable;
}
} else if (has_ce) {
if (kill_ce || kill_srst)
goto unmap_srst;
} else {
log_assert(!kill_ce);
if (kill_srst)
goto unmap_srst;
}
if (!has_ce) {
if (!has_en && (supported_cells[has_set ? FF_SDFFE1 : FF_SDFFE0] & initmask)) {
// Just add enable.
sig_e = State::S1;
ff_type = has_set ? FF_SDFFE1 : FF_SDFFE0;
break;
}
if (!has_en && (supported_cells[has_set ? FF_SDFFCE1 : FF_SDFFCE0] & initmask)) {
// Just add enable.
sig_e = State::S1;
ff_type = has_set ? FF_SDFFCE1 : FF_SDFFCE0;
break;
}
if (has_en && (supported_cells[has_set ? FF_SDFFCE1 : FF_SDFFCE0] & initmask)) {
// Convert sdffe to sdffce
if (!(ff_neg & NEG_E)) {
if (!(ff_neg & NEG_R))
sig_e = cell->module->OrGate(NEW_ID, sig_e, sig_r);
else
sig_e = cell->module->OrnotGate(NEW_ID, sig_e, sig_r);
} else {
if (!(ff_neg & NEG_R))
sig_e = cell->module->AndnotGate(NEW_ID, sig_e, sig_r);
else
sig_e = cell->module->AndGate(NEW_ID, sig_e, sig_r);
}
ff_type = has_set ? FF_SDFFCE1 : FF_SDFFCE0;
break;
}
if (has_en && (supported_cells[has_set ? FF_SDFF1 : FF_SDFF0] & initmask)) {
// Unmap enable.
ff_type = has_set ? FF_SDFF1 : FF_SDFF0;
goto unmap_enable;
}
log_assert(!((has_set ? supported_sdff1 : supported_sdff0) & initmask));
} else {
if ((has_set ? supported_sdff1 : supported_sdff0) & initmask) {
// Convert sdffce to sdffe, which may be further converted to sdff.
if (!(ff_neg & NEG_R)) {
if (!(ff_neg & NEG_E))
sig_r = cell->module->AndGate(NEW_ID, sig_r, sig_e);
else
sig_r = cell->module->AndnotGate(NEW_ID, sig_r, sig_e);
} else {
if (!(ff_neg & NEG_E))
sig_r = cell->module->OrnotGate(NEW_ID, sig_r, sig_e);
else
sig_r = cell->module->OrGate(NEW_ID, sig_r, sig_e);
}
ff_type = has_set ? FF_SDFFE1 : FF_SDFFE0;
continue;
}
}
// Alright, so this particular combination of initval and
// resetval is not natively supported. First, try flipping
// them both to see whether this helps.
if ((has_set ? supported_sdff0 : supported_sdff1) & flip_initmask(initmask)) {
// Checks out, do it.
ff_type = has_ce ? (has_set ? FF_SDFFCE0 : FF_SDFFCE1) : has_en ? (has_set ? FF_SDFFE0 : FF_SDFFE1) : (has_set ? FF_SDFF0 : FF_SDFF1);
goto flip_dqi;
}
// Nope. No way to get SDFF* of the right kind, so unmap it.
// For SDFFE, the enable has to be unmapped first.
if (has_en) {
ff_type = has_set ? FF_SDFF1 : FF_SDFF0;
goto unmap_enable;
}
unmap_srst:
if (has_ce)
ff_type = FF_DFFE;
else
ff_type = FF_DFF;
if (ff_neg & NEG_R)
sig_d = cell->module->MuxGate(NEW_ID, has_set ? State::S1 : State::S0, sig_d[0], sig_r[0]);
else
sig_d = cell->module->MuxGate(NEW_ID, sig_d[0], has_set ? State::S1 : State::S0, sig_r[0]);
ff_neg &= ~NEG_R;
sig_r = SigSpec();
kill_srst = false;
continue;
} else {
log_assert(0);
}
}
cell_ok:
if (!(supported_cells_neg[ff_type][ff_neg] & initmask)) {
// Cell is supported, but not with those polarities.
// Will need to add some inverters.
// Find the smallest value that xored with the neg mask
// results in a supported one — this results in preferentially
// inverting resets before clocks, etc.
int xneg;
for (xneg = 0; xneg < NUM_NEG; xneg++)
if (supported_cells_neg[ff_type][ff_neg ^ xneg] & initmask)
break;
log_assert(xneg < NUM_NEG);
if (xneg & NEG_R)
sig_r = cell->module->NotGate(NEW_ID, sig_r[0]);
if (xneg & NEG_S)
sig_s = cell->module->NotGate(NEW_ID, sig_s[0]);
if (xneg & NEG_E)
sig_e = cell->module->NotGate(NEW_ID, sig_e[0]);
if (xneg & NEG_C)
sig_c = cell->module->NotGate(NEW_ID, sig_c[0]);
ff_neg ^= xneg;
}
cell->unsetPort(ID::D);
cell->unsetPort(ID::Q);
cell->unsetPort(ID::C);
cell->unsetPort(ID::E);
cell->unsetPort(ID::S);
cell->unsetPort(ID::R);
switch (ff_type) {
case FF_DFF:
cell->type = IdString(stringf("$_DFF_%c_",
(ff_neg & NEG_C) ? 'N' : 'P'
));
cell->setPort(ID::D, sig_d);
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::C, sig_c);
break;
case FF_DFFE:
cell->type = IdString(stringf("$_DFFE_%c%c_",
(ff_neg & NEG_C) ? 'N' : 'P',
(ff_neg & NEG_E) ? 'N' : 'P'
));
cell->setPort(ID::D, sig_d);
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::C, sig_c);
cell->setPort(ID::E, sig_e);
break;
case FF_ADFF0:
case FF_ADFF1:
cell->type = IdString(stringf("$_DFF_%c%c%c_",
(ff_neg & NEG_C) ? 'N' : 'P',
(ff_neg & NEG_R) ? 'N' : 'P',
(ff_type == FF_ADFF1) ? '1' : '0'
));
cell->setPort(ID::D, sig_d);
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::C, sig_c);
cell->setPort(ID::R, sig_r);
break;
case FF_ADFFE0:
case FF_ADFFE1:
cell->type = IdString(stringf("$_DFFE_%c%c%c%c_",
(ff_neg & NEG_C) ? 'N' : 'P',
(ff_neg & NEG_R) ? 'N' : 'P',
(ff_type == FF_ADFFE1) ? '1' : '0',
(ff_neg & NEG_E) ? 'N' : 'P'
));
cell->setPort(ID::D, sig_d);
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::C, sig_c);
cell->setPort(ID::E, sig_e);
cell->setPort(ID::R, sig_r);
break;
case FF_DFFSR:
cell->type = IdString(stringf("$_DFFSR_%c%c%c_",
(ff_neg & NEG_C) ? 'N' : 'P',
(ff_neg & NEG_S) ? 'N' : 'P',
(ff_neg & NEG_R) ? 'N' : 'P'
));
cell->setPort(ID::D, sig_d);
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::C, sig_c);
cell->setPort(ID::S, sig_s);
cell->setPort(ID::R, sig_r);
break;
case FF_DFFSRE:
cell->type = IdString(stringf("$_DFFSRE_%c%c%c%c_",
(ff_neg & NEG_C) ? 'N' : 'P',
(ff_neg & NEG_S) ? 'N' : 'P',
(ff_neg & NEG_R) ? 'N' : 'P',
(ff_neg & NEG_E) ? 'N' : 'P'
));
cell->setPort(ID::D, sig_d);
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::C, sig_c);
cell->setPort(ID::E, sig_e);
cell->setPort(ID::S, sig_s);
cell->setPort(ID::R, sig_r);
break;
case FF_SDFF0:
case FF_SDFF1:
cell->type = IdString(stringf("$_SDFF_%c%c%c_",
(ff_neg & NEG_C) ? 'N' : 'P',
(ff_neg & NEG_R) ? 'N' : 'P',
(ff_type == FF_SDFF1) ? '1' : '0'
));
cell->setPort(ID::D, sig_d);
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::C, sig_c);
cell->setPort(ID::R, sig_r);
break;
case FF_SDFFE0:
case FF_SDFFE1:
cell->type = IdString(stringf("$_SDFFE_%c%c%c%c_",
(ff_neg & NEG_C) ? 'N' : 'P',
(ff_neg & NEG_R) ? 'N' : 'P',
(ff_type == FF_SDFFE1) ? '1' : '0',
(ff_neg & NEG_E) ? 'N' : 'P'
));
cell->setPort(ID::D, sig_d);
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::C, sig_c);
cell->setPort(ID::E, sig_e);
cell->setPort(ID::R, sig_r);
break;
case FF_SDFFCE0:
case FF_SDFFCE1:
cell->type = IdString(stringf("$_SDFFCE_%c%c%c%c_",
(ff_neg & NEG_C) ? 'N' : 'P',
(ff_neg & NEG_R) ? 'N' : 'P',
(ff_type == FF_SDFFCE1) ? '1' : '0',
(ff_neg & NEG_E) ? 'N' : 'P'
));
cell->setPort(ID::D, sig_d);
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::C, sig_c);
cell->setPort(ID::E, sig_e);
cell->setPort(ID::R, sig_r);
break;
case FF_DLATCH:
cell->type = IdString(stringf("$_DLATCH_%c_",
(ff_neg & NEG_E) ? 'N' : 'P'
));
cell->setPort(ID::D, sig_d);
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::E, sig_e);
break;
case FF_ADLATCH0:
case FF_ADLATCH1:
cell->type = IdString(stringf("$_DLATCH_%c%c%c_",
(ff_neg & NEG_E) ? 'N' : 'P',
(ff_neg & NEG_R) ? 'N' : 'P',
(ff_type == FF_ADLATCH1) ? '1' : '0'
));
cell->setPort(ID::D, sig_d);
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::E, sig_e);
cell->setPort(ID::R, sig_r);
break;
case FF_DLATCHSR:
cell->type = IdString(stringf("$_DLATCHSR_%c%c%c_",
(ff_neg & NEG_E) ? 'N' : 'P',
(ff_neg & NEG_S) ? 'N' : 'P',
(ff_neg & NEG_R) ? 'N' : 'P'
));
cell->setPort(ID::D, sig_d);
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::E, sig_e);
cell->setPort(ID::S, sig_s);
cell->setPort(ID::R, sig_r);
break;
case FF_SR:
cell->type = IdString(stringf("$_SR_%c%c_",
(ff_neg & NEG_S) ? 'N' : 'P',
(ff_neg & NEG_R) ? 'N' : 'P'
));
cell->setPort(ID::Q, sig_q);
cell->setPort(ID::S, sig_s);
cell->setPort(ID::R, sig_r);
break;
default:
log_assert(0);
}
return;
error:
log_error("FF %s.%s (type %s) cannot be legalized: %s\n", log_id(cell->module->name), log_id(cell->name), log_id(cell->type), reason);
}
void execute(std::vector<std::string> args, RTLIL::Design *design) override
{
log_header(design, "Executing DFFLEGALIZE pass (convert FFs to types supported by the target).\n");
for (int i = 0; i < NUM_FFTYPES; i++) {
for (int j = 0; j < NUM_NEG; j++)
supported_cells_neg[i][j] = 0;
supported_cells[i] = 0;
}
mince = 0;
minsrst = 0;
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++)
{
if (args[argidx] == "-cell" && argidx + 2 < args.size()) {
std::string celltype = args[++argidx];
std::string inittype = args[++argidx];
enum FfType ff_type[2] = {NUM_FFTYPES, NUM_FFTYPES};
char pol_c = 0;
char pol_e = 0;
char pol_s = 0;
char pol_r = 0;
char srval = 0;
if (celltype.substr(0, 5) == "$_SR_" && celltype.size() == 8 && celltype[7] == '_') {
ff_type[0] = FF_SR;
pol_s = celltype[5];
pol_r = celltype[6];
} else if (celltype.substr(0, 6) == "$_DFF_" && celltype.size() == 8 && celltype[7] == '_') {
ff_type[0] = FF_DFF;
pol_c = celltype[6];
} else if (celltype.substr(0, 7) == "$_DFFE_" && celltype.size() == 10 && celltype[9] == '_') {
ff_type[0] = FF_DFFE;
pol_c = celltype[7];
pol_e = celltype[8];
} else if (celltype.substr(0, 6) == "$_DFF_" && celltype.size() == 10 && celltype[9] == '_') {
ff_type[0] = FF_ADFF0;
ff_type[1] = FF_ADFF1;
pol_c = celltype[6];
pol_r = celltype[7];
srval = celltype[8];
} else if (celltype.substr(0, 7) == "$_DFFE_" && celltype.size() == 12 && celltype[11] == '_') {
ff_type[0] = FF_ADFFE0;
ff_type[1] = FF_ADFFE1;
pol_c = celltype[7];
pol_r = celltype[8];
srval = celltype[9];
pol_e = celltype[10];
} else if (celltype.substr(0, 8) == "$_DFFSR_" && celltype.size() == 12 && celltype[11] == '_') {
ff_type[0] = FF_DFFSR;
pol_c = celltype[8];
pol_s = celltype[9];
pol_r = celltype[10];
} else if (celltype.substr(0, 9) == "$_DFFSRE_" && celltype.size() == 14 && celltype[13] == '_') {
ff_type[0] = FF_DFFSRE;
pol_c = celltype[9];
pol_s = celltype[10];
pol_r = celltype[11];
pol_e = celltype[12];
} else if (celltype.substr(0, 7) == "$_SDFF_" && celltype.size() == 11 && celltype[10] == '_') {
ff_type[0] = FF_SDFF0;
ff_type[1] = FF_SDFF1;
pol_c = celltype[7];
pol_r = celltype[8];
srval = celltype[9];
} else if (celltype.substr(0, 8) == "$_SDFFE_" && celltype.size() == 13 && celltype[12] == '_') {
ff_type[0] = FF_SDFFE0;
ff_type[1] = FF_SDFFE1;
pol_c = celltype[8];
pol_r = celltype[9];
srval = celltype[10];
pol_e = celltype[11];
} else if (celltype.substr(0, 9) == "$_SDFFCE_" && celltype.size() == 14 && celltype[13] == '_') {
ff_type[0] = FF_SDFFCE0;
ff_type[1] = FF_SDFFCE1;
pol_c = celltype[9];
pol_r = celltype[10];
srval = celltype[11];
pol_e = celltype[12];
} else if (celltype.substr(0, 9) == "$_DLATCH_" && celltype.size() == 11 && celltype[10] == '_') {
ff_type[0] = FF_DLATCH;
pol_e = celltype[9];
} else if (celltype.substr(0, 9) == "$_DLATCH_" && celltype.size() == 13 && celltype[12] == '_') {
ff_type[0] = FF_ADLATCH0;
ff_type[1] = FF_ADLATCH1;
pol_e = celltype[9];
pol_r = celltype[10];
srval = celltype[11];
} else if (celltype.substr(0, 11) == "$_DLATCHSR_" && celltype.size() == 15 && celltype[14] == '_') {
ff_type[0] = FF_DLATCHSR;
pol_e = celltype[11];
pol_s = celltype[12];
pol_r = celltype[13];
} else {
unrecognized:
log_error("unrecognized cell type %s.\n", celltype.c_str());
}
int mask = 0;
int match = 0;
for (auto pair : {
std::make_pair(pol_c, NEG_C),
std::make_pair(pol_e, NEG_E),
std::make_pair(pol_s, NEG_S),
std::make_pair(pol_r, NEG_R),
}) {
if (pair.first == 'N') {
mask |= pair.second;
match |= pair.second;
} else if (pair.first == 'P' || pair.first == 0) {
mask |= pair.second;
} else if (pair.first != '?') {
goto unrecognized;
}
}
if (srval == '0') {
ff_type[1] = NUM_FFTYPES;
} else if (srval == '1') {
ff_type[0] = NUM_FFTYPES;
} else if (srval != 0 && srval != '?') {
goto unrecognized;
}
for (int i = 0; i < 2; i++) {
if (ff_type[i] == NUM_FFTYPES)
continue;
int initmask;
if (inittype == "x") {
initmask = INIT_X;
} else if (inittype == "0") {
initmask = INIT_X | INIT_0;
} else if (inittype == "1") {
initmask = INIT_X | INIT_1;
} else if (inittype == "r") {
if (srval == 0)
log_error("init type r not valid for cell type %s.\n", celltype.c_str());
if (i == 0)
initmask = INIT_X | INIT_0;
else
initmask = INIT_X | INIT_1;
} else if (inittype == "01") {
initmask = INIT_X | INIT_0 | INIT_1;
} else {
log_error("unrecognized init type %s for cell type %s.\n", inittype.c_str(), celltype.c_str());
}
for (int neg = 0; neg < NUM_NEG; neg++)
if ((neg & mask) == match)
supported_cells_neg[ff_type[i]][neg] |= initmask;
supported_cells[ff_type[i]] |= initmask;
}
continue;
} else if (args[argidx] == "-mince" && argidx + 1 < args.size()) {
mince = atoi(args[++argidx].c_str());
continue;
} else if (args[argidx] == "-minsrst" && argidx + 1 < args.size()) {
minsrst = atoi(args[++argidx].c_str());
continue;
}
break;
}
extra_args(args, argidx, design);
supported_dffsr = supported_cells[FF_DFFSR] | supported_cells[FF_DFFSRE];
supported_adff0 = supported_cells[FF_ADFF0] | supported_cells[FF_ADFFE0] | supported_dffsr;
supported_adff1 = supported_cells[FF_ADFF1] | supported_cells[FF_ADFFE1] | supported_dffsr;
supported_sdff0 = supported_cells[FF_SDFF0] | supported_cells[FF_SDFFE0] | supported_cells[FF_SDFFCE0];
supported_sdff1 = supported_cells[FF_SDFF1] | supported_cells[FF_SDFFE1] | supported_cells[FF_SDFFCE1];
supported_dff = supported_cells[FF_DFF] | supported_cells[FF_DFFE] | supported_dffsr | supported_adff0 | supported_adff1 | supported_sdff0 | supported_sdff1;
supported_sr = supported_dffsr | supported_cells[FF_DLATCHSR] | supported_cells[FF_SR] | supported_cells[FF_ADLATCH0] | flip_initmask(supported_cells[FF_ADLATCH1]);
supported_dlatch = supported_cells[FF_DLATCH] | supported_cells[FF_ADLATCH0] | supported_cells[FF_ADLATCH1] | supported_cells[FF_DLATCHSR];
for (auto module : design->selected_modules())
{
sigmap.set(module);
initvals.set(&sigmap, module);
if (mince || minsrst) {
ce_used.clear();
srst_used.clear();
for (auto cell : module->cells()) {
if (!RTLIL::builtin_ff_cell_types().count(cell->type))
continue;
if (cell->hasPort(ID::C) && cell->hasPort(ID::E)) {
SigSpec sig = cell->getPort(ID::E);
// Do not count const enable signals.
if (GetSize(sig) == 1 && sig[0].wire)
ce_used[sig[0]]++;
}
if (cell->type.str().substr(0, 6) == "$_SDFF") {
SigSpec sig = cell->getPort(ID::R);
// Do not count const srst signals.
if (GetSize(sig) == 1 && sig[0].wire)
srst_used[sig[0]]++;
}
}
}
// First gather FF cells, then iterate over them later.
// We may need to split an FF into several cells.
std::vector<Cell *> ff_cells;
for (auto cell : module->selected_cells())
{
// Early exit for non-FFs.
if (!RTLIL::builtin_ff_cell_types().count(cell->type))
continue;
ff_cells.push_back(cell);
}
for (auto cell: ff_cells)
handle_ff(cell);
}
sigmap.clear();
initvals.clear();
ce_used.clear();
srst_used.clear();
}
} DffLegalizePass;
PRIVATE_NAMESPACE_END
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