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-rw-r--r--passes/opt/Makefile.inc1
-rw-r--r--passes/opt/opt.cc1
-rw-r--r--passes/opt/opt_dff.cc212
-rw-r--r--passes/opt/opt_ffinv.cc265
-rw-r--r--passes/opt/opt_mem.cc156
-rw-r--r--passes/opt/opt_merge.cc22
-rw-r--r--passes/opt/opt_reduce.cc397
-rw-r--r--passes/opt/wreduce.cc10
8 files changed, 889 insertions, 175 deletions
diff --git a/passes/opt/Makefile.inc b/passes/opt/Makefile.inc
index 4e52ad8da..76bf8a84e 100644
--- a/passes/opt/Makefile.inc
+++ b/passes/opt/Makefile.inc
@@ -19,6 +19,7 @@ OBJS += passes/opt/opt_demorgan.o
OBJS += passes/opt/rmports.o
OBJS += passes/opt/opt_lut.o
OBJS += passes/opt/opt_lut_ins.o
+OBJS += passes/opt/opt_ffinv.o
OBJS += passes/opt/pmux2shiftx.o
OBJS += passes/opt/muxpack.o
endif
diff --git a/passes/opt/opt.cc b/passes/opt/opt.cc
index c3e418c07..dc88563c2 100644
--- a/passes/opt/opt.cc
+++ b/passes/opt/opt.cc
@@ -114,6 +114,7 @@ struct OptPass : public Pass {
if (args[argidx] == "-keepdc") {
opt_expr_args += " -keepdc";
opt_dff_args += " -keepdc";
+ opt_merge_args += " -keepdc";
continue;
}
if (args[argidx] == "-nodffe") {
diff --git a/passes/opt/opt_dff.cc b/passes/opt/opt_dff.cc
index 98b66dee3..0ad4acec2 100644
--- a/passes/opt/opt_dff.cc
+++ b/passes/opt/opt_dff.cc
@@ -58,13 +58,10 @@ struct OptDffWorker
typedef std::pair<RTLIL::SigBit, bool> ctrl_t;
typedef std::set<ctrl_t> ctrls_t;
- ModWalker modwalker;
- QuickConeSat qcsat;
-
// Used as a queue.
std::vector<Cell *> dff_cells;
- OptDffWorker(const OptDffOptions &opt, Module *mod) : opt(opt), module(mod), sigmap(mod), initvals(&sigmap, mod), modwalker(module->design, module), qcsat(modwalker) {
+ OptDffWorker(const OptDffOptions &opt, Module *mod) : opt(opt), module(mod), sigmap(mod), initvals(&sigmap, mod) {
// Gathering two kinds of information here for every sigmapped SigBit:
//
// - bitusers: how many users it has (muxes will only be merged into FFs if this is 1, making the FF the only user)
@@ -557,7 +554,7 @@ struct OptDffWorker
// The D input path is effectively useless, so remove it (this will be a const-input D latch, SR latch, or a const driver).
log("Handling D = Q on %s (%s) from module %s (removing D path).\n",
log_id(cell), log_id(cell->type), log_id(module));
- ff.has_clk = ff.has_ce = false;
+ ff.has_gclk = ff.has_clk = ff.has_ce = false;
changed = true;
}
}
@@ -569,100 +566,6 @@ struct OptDffWorker
changed = true;
}
- // Now check if any bit can be replaced by a constant.
- pool<int> removed_sigbits;
- for (int i = 0; i < ff.width; i++) {
- State val = ff.val_init[i];
- if (ff.has_arst)
- val = combine_const(val, ff.val_arst[i]);
- if (ff.has_srst)
- val = combine_const(val, ff.val_srst[i]);
- if (ff.has_sr) {
- if (ff.sig_clr[i] != (ff.pol_clr ? State::S0 : State::S1))
- val = combine_const(val, State::S0);
- if (ff.sig_set[i] != (ff.pol_set ? State::S0 : State::S1))
- val = combine_const(val, State::S1);
- }
- if (val == State::Sm)
- continue;
- if (ff.has_clk || ff.has_gclk) {
- if (!ff.sig_d[i].wire) {
- val = combine_const(val, ff.sig_d[i].data);
- if (val == State::Sm)
- continue;
- } else {
- if (!opt.sat)
- continue;
- // For each register bit, try to prove that it cannot change from the initial value. If so, remove it
- if (!modwalker.has_drivers(ff.sig_d.extract(i)))
- continue;
- if (val != State::S0 && val != State::S1)
- continue;
-
- int init_sat_pi = qcsat.importSigBit(val);
- int q_sat_pi = qcsat.importSigBit(ff.sig_q[i]);
- int d_sat_pi = qcsat.importSigBit(ff.sig_d[i]);
-
- qcsat.prepare();
-
- // Try to find out whether the register bit can change under some circumstances
- bool counter_example_found = qcsat.ez->solve(qcsat.ez->IFF(q_sat_pi, init_sat_pi), qcsat.ez->NOT(qcsat.ez->IFF(d_sat_pi, init_sat_pi)));
-
- // If the register bit cannot change, we can replace it with a constant
- if (counter_example_found)
- continue;
- }
- }
- if (ff.has_aload) {
- if (!ff.sig_ad[i].wire) {
- val = combine_const(val, ff.sig_ad[i].data);
- if (val == State::Sm)
- continue;
- } else {
- if (!opt.sat)
- continue;
- // For each register bit, try to prove that it cannot change from the initial value. If so, remove it
- if (!modwalker.has_drivers(ff.sig_ad.extract(i)))
- continue;
- if (val != State::S0 && val != State::S1)
- continue;
-
- int init_sat_pi = qcsat.importSigBit(val);
- int q_sat_pi = qcsat.importSigBit(ff.sig_q[i]);
- int d_sat_pi = qcsat.importSigBit(ff.sig_ad[i]);
-
- qcsat.prepare();
-
- // Try to find out whether the register bit can change under some circumstances
- bool counter_example_found = qcsat.ez->solve(qcsat.ez->IFF(q_sat_pi, init_sat_pi), qcsat.ez->NOT(qcsat.ez->IFF(d_sat_pi, init_sat_pi)));
-
- // If the register bit cannot change, we can replace it with a constant
- if (counter_example_found)
- continue;
- }
- }
- log("Setting constant %d-bit at position %d on %s (%s) from module %s.\n", val ? 1 : 0,
- i, log_id(cell), log_id(cell->type), log_id(module));
-
- initvals.remove_init(ff.sig_q[i]);
- module->connect(ff.sig_q[i], val);
- removed_sigbits.insert(i);
- }
- if (!removed_sigbits.empty()) {
- std::vector<int> keep_bits;
- for (int i = 0; i < ff.width; i++)
- if (!removed_sigbits.count(i))
- keep_bits.push_back(i);
- if (keep_bits.empty()) {
- module->remove(cell);
- did_something = true;
- continue;
- }
- ff = ff.slice(keep_bits);
- ff.cell = cell;
- changed = true;
- }
-
// The cell has been simplified as much as possible already. Now try to spice it up with enables / sync resets.
if (ff.has_clk) {
if (!ff.has_arst && !ff.has_sr && (!ff.has_srst || !ff.has_ce || ff.ce_over_srst) && !opt.nosdff) {
@@ -818,6 +721,115 @@ struct OptDffWorker
}
return did_something;
}
+
+ bool run_constbits() {
+ ModWalker modwalker(module->design, module);
+ QuickConeSat qcsat(modwalker);
+
+ // Run as a separate sub-pass, so that we don't mutate (non-FF) cells under ModWalker.
+ bool did_something = false;
+ for (auto cell : module->selected_cells()) {
+ if (!RTLIL::builtin_ff_cell_types().count(cell->type))
+ continue;
+ FfData ff(&initvals, cell);
+
+ // Now check if any bit can be replaced by a constant.
+ pool<int> removed_sigbits;
+ for (int i = 0; i < ff.width; i++) {
+ State val = ff.val_init[i];
+ if (ff.has_arst)
+ val = combine_const(val, ff.val_arst[i]);
+ if (ff.has_srst)
+ val = combine_const(val, ff.val_srst[i]);
+ if (ff.has_sr) {
+ if (ff.sig_clr[i] != (ff.pol_clr ? State::S0 : State::S1))
+ val = combine_const(val, State::S0);
+ if (ff.sig_set[i] != (ff.pol_set ? State::S0 : State::S1))
+ val = combine_const(val, State::S1);
+ }
+ if (val == State::Sm)
+ continue;
+ if (ff.has_clk || ff.has_gclk) {
+ if (!ff.sig_d[i].wire) {
+ val = combine_const(val, ff.sig_d[i].data);
+ if (val == State::Sm)
+ continue;
+ } else {
+ if (!opt.sat)
+ continue;
+ // For each register bit, try to prove that it cannot change from the initial value. If so, remove it
+ if (!modwalker.has_drivers(ff.sig_d.extract(i)))
+ continue;
+ if (val != State::S0 && val != State::S1)
+ continue;
+
+ int init_sat_pi = qcsat.importSigBit(val);
+ int q_sat_pi = qcsat.importSigBit(ff.sig_q[i]);
+ int d_sat_pi = qcsat.importSigBit(ff.sig_d[i]);
+
+ qcsat.prepare();
+
+ // Try to find out whether the register bit can change under some circumstances
+ bool counter_example_found = qcsat.ez->solve(qcsat.ez->IFF(q_sat_pi, init_sat_pi), qcsat.ez->NOT(qcsat.ez->IFF(d_sat_pi, init_sat_pi)));
+
+ // If the register bit cannot change, we can replace it with a constant
+ if (counter_example_found)
+ continue;
+ }
+ }
+ if (ff.has_aload) {
+ if (!ff.sig_ad[i].wire) {
+ val = combine_const(val, ff.sig_ad[i].data);
+ if (val == State::Sm)
+ continue;
+ } else {
+ if (!opt.sat)
+ continue;
+ // For each register bit, try to prove that it cannot change from the initial value. If so, remove it
+ if (!modwalker.has_drivers(ff.sig_ad.extract(i)))
+ continue;
+ if (val != State::S0 && val != State::S1)
+ continue;
+
+ int init_sat_pi = qcsat.importSigBit(val);
+ int q_sat_pi = qcsat.importSigBit(ff.sig_q[i]);
+ int d_sat_pi = qcsat.importSigBit(ff.sig_ad[i]);
+
+ qcsat.prepare();
+
+ // Try to find out whether the register bit can change under some circumstances
+ bool counter_example_found = qcsat.ez->solve(qcsat.ez->IFF(q_sat_pi, init_sat_pi), qcsat.ez->NOT(qcsat.ez->IFF(d_sat_pi, init_sat_pi)));
+
+ // If the register bit cannot change, we can replace it with a constant
+ if (counter_example_found)
+ continue;
+ }
+ }
+ log("Setting constant %d-bit at position %d on %s (%s) from module %s.\n", val ? 1 : 0,
+ i, log_id(cell), log_id(cell->type), log_id(module));
+
+ initvals.remove_init(ff.sig_q[i]);
+ module->connect(ff.sig_q[i], val);
+ removed_sigbits.insert(i);
+ }
+ if (!removed_sigbits.empty()) {
+ std::vector<int> keep_bits;
+ for (int i = 0; i < ff.width; i++)
+ if (!removed_sigbits.count(i))
+ keep_bits.push_back(i);
+ if (keep_bits.empty()) {
+ module->remove(cell);
+ did_something = true;
+ continue;
+ }
+ ff = ff.slice(keep_bits);
+ ff.cell = cell;
+ ff.emit();
+ did_something = true;
+ }
+ }
+ return did_something;
+ }
};
struct OptDffPass : public Pass {
@@ -894,6 +906,8 @@ struct OptDffPass : public Pass {
OptDffWorker worker(opt, mod);
if (worker.run())
did_something = true;
+ if (worker.run_constbits())
+ did_something = true;
}
if (did_something)
diff --git a/passes/opt/opt_ffinv.cc b/passes/opt/opt_ffinv.cc
new file mode 100644
index 000000000..5d989dafd
--- /dev/null
+++ b/passes/opt/opt_ffinv.cc
@@ -0,0 +1,265 @@
+/*
+ * yosys -- Yosys Open SYnthesis Suite
+ *
+ * Copyright (C) 2022 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/modtools.h"
+#include "kernel/ffinit.h"
+#include "kernel/ff.h"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+struct OptFfInvWorker
+{
+ int count = 0;
+ RTLIL::Module *module;
+ ModIndex index;
+ FfInitVals initvals;
+
+ // Case 1:
+ // - FF is driven by inverter
+ // - ... which has no other users
+ // - all users of FF are LUTs
+ bool push_d_inv(FfData &ff) {
+ if (index.query_is_input(ff.sig_d))
+ return false;
+ if (index.query_is_output(ff.sig_d))
+ return false;
+ auto d_ports = index.query_ports(ff.sig_d);
+ if (d_ports.size() != 2)
+ return false;
+ Cell *d_inv = nullptr;
+ for (auto &port: d_ports) {
+ if (port.cell == ff.cell && port.port == ID::D)
+ continue;
+ if (port.port != ID::Y)
+ return false;
+ if (port.cell->type.in(ID($not), ID($_NOT_))) {
+ // OK
+ } else if (port.cell->type.in(ID($lut))) {
+ if (port.cell->getParam(ID::WIDTH) != 1)
+ return false;
+ if (port.cell->getParam(ID::LUT).as_int() != 1)
+ return false;
+ } else {
+ return false;
+ }
+ log_assert(d_inv == nullptr);
+ d_inv = port.cell;
+ }
+
+ if (index.query_is_output(ff.sig_q))
+ return false;
+ auto q_ports = index.query_ports(ff.sig_q);
+ pool<Cell *> q_luts;
+ for (auto &port: q_ports) {
+ if (port.cell == ff.cell && port.port == ID::Q)
+ continue;
+ if (port.cell == d_inv)
+ return false;
+ if (port.port != ID::A)
+ return false;
+ if (!port.cell->type.in(ID($not), ID($_NOT_), ID($lut)))
+ return false;
+ q_luts.insert(port.cell);
+ }
+
+ ff.flip_rst_bits({0});
+ ff.sig_d = d_inv->getPort(ID::A);
+
+ for (Cell *lut: q_luts) {
+ if (lut->type == ID($lut)) {
+ int flip_mask = 0;
+ SigSpec sig_a = lut->getPort(ID::A);
+ for (int i = 0; i < GetSize(sig_a); i++) {
+ if (index.sigmap(sig_a[i]) == index.sigmap(ff.sig_q)) {
+ flip_mask |= 1 << i;
+ }
+ }
+ Const mask = lut->getParam(ID::LUT);
+ Const new_mask;
+ for (int j = 0; j < (1 << GetSize(sig_a)); j++) {
+ new_mask.bits.push_back(mask.bits[j ^ flip_mask]);
+ }
+ if (GetSize(sig_a) == 1 && new_mask.as_int() == 2) {
+ module->connect(lut->getPort(ID::Y), ff.sig_q);
+ module->remove(lut);
+ } else {
+ lut->setParam(ID::LUT, new_mask);
+ }
+ } else {
+ // it was an inverter
+ module->connect(lut->getPort(ID::Y), ff.sig_q);
+ module->remove(lut);
+ }
+ }
+
+ ff.emit();
+ return true;
+ }
+
+ // Case 2:
+ // - FF is driven by LUT
+ // - ... which has no other users
+ // - FF has one user
+ // - ... which is an inverter
+ bool push_q_inv(FfData &ff) {
+ if (index.query_is_input(ff.sig_d))
+ return false;
+ if (index.query_is_output(ff.sig_d))
+ return false;
+
+ Cell *d_lut = nullptr;
+ auto d_ports = index.query_ports(ff.sig_d);
+ if (d_ports.size() != 2)
+ return false;
+ for (auto &port: d_ports) {
+ if (port.cell == ff.cell && port.port == ID::D)
+ continue;
+ if (port.port != ID::Y)
+ return false;
+ if (!port.cell->type.in(ID($not), ID($_NOT_), ID($lut)))
+ return false;
+ log_assert(d_lut == nullptr);
+ d_lut = port.cell;
+ }
+
+ if (index.query_is_output(ff.sig_q))
+ return false;
+ auto q_ports = index.query_ports(ff.sig_q);
+ if (q_ports.size() != 2)
+ return false;
+ Cell *q_inv = nullptr;
+ for (auto &port: q_ports) {
+ if (port.cell == ff.cell && port.port == ID::Q)
+ continue;
+ if (port.cell == d_lut)
+ return false;
+ if (port.port != ID::A)
+ return false;
+ if (port.cell->type.in(ID($not), ID($_NOT_))) {
+ // OK
+ } else if (port.cell->type.in(ID($lut))) {
+ if (port.cell->getParam(ID::WIDTH) != 1)
+ return false;
+ if (port.cell->getParam(ID::LUT).as_int() != 1)
+ return false;
+ } else {
+ return false;
+ }
+ log_assert(q_inv == nullptr);
+ q_inv = port.cell;
+ }
+
+ ff.flip_rst_bits({0});
+ ff.sig_q = q_inv->getPort(ID::Y);
+ module->remove(q_inv);
+
+ if (d_lut->type == ID($lut)) {
+ Const mask = d_lut->getParam(ID::LUT);
+ Const new_mask;
+ for (int i = 0; i < GetSize(mask); i++) {
+ if (mask.bits[i] == State::S0)
+ new_mask.bits.push_back(State::S1);
+ else
+ new_mask.bits.push_back(State::S0);
+ }
+ d_lut->setParam(ID::LUT, new_mask);
+ if (d_lut->getParam(ID::WIDTH) == 1 && new_mask.as_int() == 2) {
+ module->connect(ff.sig_d, d_lut->getPort(ID::A));
+ module->remove(d_lut);
+ }
+ } else {
+ // it was an inverter
+ module->connect(ff.sig_d, d_lut->getPort(ID::A));
+ module->remove(d_lut);
+ }
+
+ ff.emit();
+ return true;
+ }
+
+ OptFfInvWorker(RTLIL::Module *module) :
+ module(module), index(module), initvals(&index.sigmap, module)
+ {
+ log("Discovering LUTs.\n");
+
+ std::vector<Cell *> ffs;
+
+ for (Cell *cell : module->selected_cells())
+ if (RTLIL::builtin_ff_cell_types().count(cell->type))
+ ffs.push_back(cell);
+
+ for (Cell *cell : ffs) {
+ FfData ff(&initvals, cell);
+ if (ff.has_sr)
+ continue;
+ if (!ff.has_clk)
+ continue;
+ if (ff.has_aload)
+ continue;
+ if (ff.width != 1)
+ continue;
+
+ if (push_d_inv(ff)) {
+ count++;
+ } else if (push_q_inv(ff)) {
+ count++;
+ }
+ }
+ }
+};
+
+struct OptFfInvPass : public Pass {
+ OptFfInvPass() : Pass("opt_ffinv", "push inverters through FFs") { }
+ void help() override
+ {
+ // |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+ log("\n");
+ log(" opt_ffinv [selection]\n");
+ log("\n");
+ log("This pass pushes inverters to the other side of a FF when they can be merged\n");
+ log("into LUTs on the other side.\n");
+ log("\n");
+ }
+ void execute(std::vector<std::string> args, RTLIL::Design *design) override
+ {
+ log_header(design, "Executing OPT_FFINV pass (push inverters through FFs).\n");
+
+ size_t argidx;
+ for (argidx = 1; argidx < args.size(); argidx++)
+ {
+ break;
+ }
+ extra_args(args, argidx, design);
+
+ int total_count = 0;
+ for (auto module : design->selected_modules())
+ {
+ OptFfInvWorker worker(module);
+ total_count += worker.count;
+ }
+ if (total_count)
+ design->scratchpad_set_bool("opt.did_something", true);
+ log("Pushed %d inverters.\n", total_count);
+ }
+} OptFfInvPass;
+
+PRIVATE_NAMESPACE_END
diff --git a/passes/opt/opt_mem.cc b/passes/opt/opt_mem.cc
index edadf2c7b..885b6f97d 100644
--- a/passes/opt/opt_mem.cc
+++ b/passes/opt/opt_mem.cc
@@ -20,6 +20,7 @@
#include "kernel/yosys.h"
#include "kernel/sigtools.h"
#include "kernel/mem.h"
+#include "kernel/ff.h"
USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN
@@ -54,31 +55,160 @@ struct OptMemPass : public Pass {
SigMap sigmap(module);
FfInitVals initvals(&sigmap, module);
for (auto &mem : Mem::get_selected_memories(module)) {
+ std::vector<bool> always_0(mem.width, true);
+ std::vector<bool> always_1(mem.width, true);
bool changed = false;
for (auto &port : mem.wr_ports) {
if (port.en.is_fully_zero()) {
port.removed = true;
changed = true;
total_count++;
+ } else {
+ for (int sub = 0; sub < (1 << port.wide_log2); sub++) {
+ for (int i = 0; i < mem.width; i++) {
+ int bit = sub * mem.width + i;
+ if (port.en[bit] != State::S0) {
+ if (port.data[bit] != State::Sx && port.data[bit] != State::S0) {
+ always_0[i] = false;
+ }
+ if (port.data[bit] != State::Sx && port.data[bit] != State::S1) {
+ always_1[i] = false;
+ }
+ } else {
+ if (port.data[bit] != State::Sx) {
+ port.data[bit] = State::Sx;
+ changed = true;
+ total_count++;
+ }
+ }
+ }
+ }
}
}
- if (changed) {
- mem.emit();
+ for (auto &init : mem.inits) {
+ for (int i = 0; i < GetSize(init.data); i++) {
+ State bit = init.data.bits[i];
+ int lane = i % mem.width;
+ if (bit != State::Sx && bit != State::S0) {
+ always_0[lane] = false;
+ }
+ if (bit != State::Sx && bit != State::S1) {
+ always_1[lane] = false;
+ }
+ }
}
-
- if (mem.wr_ports.empty() && mem.inits.empty()) {
- // The whole memory array will contain
- // only State::Sx, but the embedded read
- // registers could have reset or init values.
- // They will probably be optimized away by
- // opt_dff later.
- for (int i = 0; i < GetSize(mem.rd_ports); i++) {
- mem.extract_rdff(i, &initvals);
- auto &port = mem.rd_ports[i];
- module->connect(port.data, Const(State::Sx, GetSize(port.data)));
+ std::vector<int> swizzle;
+ for (int i = 0; i < mem.width; i++) {
+ if (!always_0[i] && !always_1[i]) {
+ swizzle.push_back(i);
+ continue;
}
+ State bit;
+ if (!always_0[i]) {
+ log("%s.%s: removing const-1 lane %d\n", log_id(module->name), log_id(mem.memid), i);
+ bit = State::S1;
+ } else if (!always_1[i]) {
+ log("%s.%s: removing const-0 lane %d\n", log_id(module->name), log_id(mem.memid), i);
+ bit = State::S0;
+ } else {
+ log("%s.%s: removing const-x lane %d\n", log_id(module->name), log_id(mem.memid), i);
+ bit = State::Sx;
+ }
+ // Reconnect read port data.
+ for (auto &port: mem.rd_ports) {
+ for (int sub = 0; sub < (1 << port.wide_log2); sub++) {
+ int bidx = sub * mem.width + i;
+ if (!port.clk_enable) {
+ module->connect(port.data[bidx], bit);
+ } else {
+ // The FF will most likely be redundant, but it's up to opt_dff to deal with this.
+ FfData ff(module, &initvals, NEW_ID);
+ ff.width = 1;
+ ff.has_clk = true;
+ ff.sig_clk = port.clk;
+ ff.pol_clk = port.clk_polarity;
+ if (port.en != State::S1) {
+ ff.has_ce = true;
+ ff.pol_ce = true;
+ ff.sig_ce = port.en;
+ }
+ if (port.arst != State::S0) {
+ ff.has_arst = true;
+ ff.pol_arst = true;
+ ff.sig_arst = port.arst;
+ ff.val_arst = port.arst_value[bidx];
+ }
+ if (port.srst != State::S0) {
+ ff.has_srst = true;
+ ff.pol_srst = true;
+ ff.sig_srst = port.srst;
+ ff.val_srst = port.srst_value[bidx];
+ }
+ ff.sig_d = bit;
+ ff.sig_q = port.data[bidx];
+ ff.val_init = port.init_value[bidx];
+ ff.emit();
+ }
+ }
+ }
+ }
+ if (GetSize(swizzle) == 0) {
mem.remove();
total_count++;
+ continue;
+ }
+ if (GetSize(swizzle) != mem.width) {
+ for (auto &port: mem.wr_ports) {
+ SigSpec new_data;
+ SigSpec new_en;
+ for (int sub = 0; sub < (1 << port.wide_log2); sub++) {
+ for (auto i: swizzle) {
+ new_data.append(port.data[sub * mem.width + i]);
+ new_en.append(port.en[sub * mem.width + i]);
+ }
+ }
+ port.data = new_data;
+ port.en = new_en;
+ }
+ for (auto &port: mem.rd_ports) {
+ SigSpec new_data;
+ Const new_init;
+ Const new_arst;
+ Const new_srst;
+ for (int sub = 0; sub < (1 << port.wide_log2); sub++) {
+ for (auto i: swizzle) {
+ int bidx = sub * mem.width + i;
+ new_data.append(port.data[bidx]);
+ new_init.bits.push_back(port.init_value.bits[bidx]);
+ new_arst.bits.push_back(port.arst_value.bits[bidx]);
+ new_srst.bits.push_back(port.srst_value.bits[bidx]);
+ }
+ }
+ port.data = new_data;
+ port.init_value = new_init;
+ port.arst_value = new_arst;
+ port.srst_value = new_srst;
+ }
+ for (auto &init: mem.inits) {
+ Const new_data;
+ Const new_en;
+ for (int s = 0; s < GetSize(init.data); s += mem.width) {
+ for (auto i: swizzle) {
+ new_data.bits.push_back(init.data.bits[s + i]);
+ }
+ }
+ for (auto i: swizzle) {
+ new_en.bits.push_back(init.en.bits[i]);
+ }
+ init.data = new_data;
+ init.en = new_en;
+ }
+ mem.width = GetSize(swizzle);
+ changed = true;
+ total_count++;
+ }
+ if (changed) {
+ mem.emit();
}
}
}
diff --git a/passes/opt/opt_merge.cc b/passes/opt/opt_merge.cc
index 115eb97a9..e9d98cd43 100644
--- a/passes/opt/opt_merge.cc
+++ b/passes/opt/opt_merge.cc
@@ -219,7 +219,15 @@ struct OptMergeWorker
return conn1 == conn2;
}
- OptMergeWorker(RTLIL::Design *design, RTLIL::Module *module, bool mode_nomux, bool mode_share_all) :
+ bool has_dont_care_initval(const RTLIL::Cell *cell)
+ {
+ if (!RTLIL::builtin_ff_cell_types().count(cell->type))
+ return false;
+
+ return !initvals(cell->getPort(ID::Q)).is_fully_def();
+ }
+
+ OptMergeWorker(RTLIL::Design *design, RTLIL::Module *module, bool mode_nomux, bool mode_share_all, bool mode_keepdc) :
design(design), module(module), assign_map(module), mode_share_all(mode_share_all)
{
total_count = 0;
@@ -253,6 +261,8 @@ struct OptMergeWorker
for (auto &it : module->cells_) {
if (!design->selected(module, it.second))
continue;
+ if (mode_keepdc && has_dont_care_initval(it.second))
+ continue;
if (ct.cell_known(it.second->type) || (mode_share_all && it.second->known()))
cells.push_back(it.second);
}
@@ -319,6 +329,9 @@ struct OptMergePass : public Pass {
log(" -share_all\n");
log(" Operate on all cell types, not just built-in types.\n");
log("\n");
+ log(" -keepdc\n");
+ log(" Do not merge flipflops with don't-care bits in their initial value.\n");
+ log("\n");
}
void execute(std::vector<std::string> args, RTLIL::Design *design) override
{
@@ -326,6 +339,7 @@ struct OptMergePass : public Pass {
bool mode_nomux = false;
bool mode_share_all = false;
+ bool mode_keepdc = false;
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++) {
@@ -338,13 +352,17 @@ struct OptMergePass : public Pass {
mode_share_all = true;
continue;
}
+ if (arg == "-keepdc") {
+ mode_keepdc = true;
+ continue;
+ }
break;
}
extra_args(args, argidx, design);
int total_count = 0;
for (auto module : design->selected_modules()) {
- OptMergeWorker worker(design, module, mode_nomux, mode_share_all);
+ OptMergeWorker worker(design, module, mode_nomux, mode_share_all, mode_keepdc);
total_count += worker.total_count;
}
diff --git a/passes/opt/opt_reduce.cc b/passes/opt/opt_reduce.cc
index b558f547e..1a7c93fbd 100644
--- a/passes/opt/opt_reduce.cc
+++ b/passes/opt/opt_reduce.cc
@@ -100,7 +100,7 @@ struct OptReduceWorker
return;
}
- void opt_mux(RTLIL::Cell *cell)
+ void opt_pmux(RTLIL::Cell *cell)
{
RTLIL::SigSpec sig_a = assign_map(cell->getPort(ID::A));
RTLIL::SigSpec sig_b = assign_map(cell->getPort(ID::B));
@@ -141,20 +141,20 @@ struct OptReduceWorker
handled_sig.insert(this_b);
}
- if (new_sig_s.size() != sig_s.size()) {
- log(" New ctrl vector for %s cell %s: %s\n", cell->type.c_str(), cell->name.c_str(), log_signal(new_sig_s));
- did_something = true;
- total_count++;
- }
-
if (new_sig_s.size() == 0)
{
- module->connect(RTLIL::SigSig(cell->getPort(ID::Y), cell->getPort(ID::A)));
+ module->connect(cell->getPort(ID::Y), cell->getPort(ID::A));
assign_map.add(cell->getPort(ID::Y), cell->getPort(ID::A));
module->remove(cell);
+ did_something = true;
+ total_count++;
+ return;
}
- else
- {
+
+ if (new_sig_s.size() != sig_s.size() || (new_sig_s.size() == 1 && cell->type == ID($pmux))) {
+ log(" New ctrl vector for %s cell %s: %s\n", cell->type.c_str(), cell->name.c_str(), log_signal(new_sig_s));
+ did_something = true;
+ total_count++;
cell->setPort(ID::B, new_sig_b);
cell->setPort(ID::S, new_sig_s);
if (new_sig_s.size() > 1) {
@@ -166,81 +166,347 @@ struct OptReduceWorker
}
}
- void opt_mux_bits(RTLIL::Cell *cell)
+ void opt_bmux(RTLIL::Cell *cell)
{
- std::vector<RTLIL::SigBit> sig_a = assign_map(cell->getPort(ID::A)).to_sigbit_vector();
- std::vector<RTLIL::SigBit> sig_b = assign_map(cell->getPort(ID::B)).to_sigbit_vector();
- std::vector<RTLIL::SigBit> sig_y = assign_map(cell->getPort(ID::Y)).to_sigbit_vector();
+ RTLIL::SigSpec sig_a = assign_map(cell->getPort(ID::A));
+ RTLIL::SigSpec sig_s = assign_map(cell->getPort(ID::S));
+ int width = cell->getParam(ID::WIDTH).as_int();
+
+ RTLIL::SigSpec new_sig_a, new_sig_s;
+ dict<RTLIL::SigBit, int> handled_bits;
+
+ // 0 and up: index of new_sig_s bit
+ // -1: const 0
+ // -2: const 1
+ std::vector<int> swizzle;
+
+ for (int i = 0; i < sig_s.size(); i++)
+ {
+ SigBit bit = sig_s[i];
+ if (bit == State::S0) {
+ swizzle.push_back(-1);
+ } else if (bit == State::S1) {
+ swizzle.push_back(-2);
+ } else {
+ auto it = handled_bits.find(bit);
+ if (it == handled_bits.end()) {
+ int new_idx = GetSize(new_sig_s);
+ new_sig_s.append(bit);
+ handled_bits[bit] = new_idx;
+ swizzle.push_back(new_idx);
+ } else {
+ swizzle.push_back(it->second);
+ }
+ }
+ }
+
+ for (int i = 0; i < (1 << GetSize(new_sig_s)); i++) {
+ int idx = 0;
+ for (int j = 0; j < GetSize(sig_s); j++) {
+ if (swizzle[j] == -1) {
+ // const 0.
+ } else if (swizzle[j] == -2) {
+ // const 1.
+ idx |= 1 << j;
+ } else {
+ if (i & 1 << swizzle[j])
+ idx |= 1 << j;
+ }
+ }
+ new_sig_a.append(sig_a.extract(idx * width, width));
+ }
+
+ if (new_sig_s.size() == 0)
+ {
+ module->connect(cell->getPort(ID::Y), new_sig_a);
+ assign_map.add(cell->getPort(ID::Y), new_sig_a);
+ module->remove(cell);
+ did_something = true;
+ total_count++;
+ return;
+ }
+
+ if (new_sig_s.size() == 1)
+ {
+ cell->type = ID($mux);
+ cell->setPort(ID::A, new_sig_a.extract(0, width));
+ cell->setPort(ID::B, new_sig_a.extract(width, width));
+ cell->setPort(ID::S, new_sig_s);
+ cell->parameters.erase(ID::S_WIDTH);
+ did_something = true;
+ total_count++;
+ return;
+ }
+
+ if (new_sig_s.size() != sig_s.size()) {
+ log(" New ctrl vector for %s cell %s: %s\n", cell->type.c_str(), cell->name.c_str(), log_signal(new_sig_s));
+ did_something = true;
+ total_count++;
+ cell->setPort(ID::A, new_sig_a);
+ cell->setPort(ID::S, new_sig_s);
+ cell->parameters[ID::S_WIDTH] = RTLIL::Const(new_sig_s.size());
+ }
+ }
+
+ void opt_demux(RTLIL::Cell *cell)
+ {
+ RTLIL::SigSpec sig_y = assign_map(cell->getPort(ID::Y));
+ RTLIL::SigSpec sig_s = assign_map(cell->getPort(ID::S));
+ int width = cell->getParam(ID::WIDTH).as_int();
+
+ RTLIL::SigSpec new_sig_y, new_sig_s;
+ dict<RTLIL::SigBit, int> handled_bits;
+
+ // 0 and up: index of new_sig_s bit
+ // -1: const 0
+ // -2: const 1
+ std::vector<int> swizzle;
+
+ for (int i = 0; i < sig_s.size(); i++)
+ {
+ SigBit bit = sig_s[i];
+ if (bit == State::S0) {
+ swizzle.push_back(-1);
+ } else if (bit == State::S1) {
+ swizzle.push_back(-2);
+ } else {
+ auto it = handled_bits.find(bit);
+ if (it == handled_bits.end()) {
+ int new_idx = GetSize(new_sig_s);
+ new_sig_s.append(bit);
+ handled_bits[bit] = new_idx;
+ swizzle.push_back(new_idx);
+ } else {
+ swizzle.push_back(it->second);
+ }
+ }
+ }
+
+ pool<int> nonzero_idx;
+
+ for (int i = 0; i < (1 << GetSize(new_sig_s)); i++) {
+ int idx = 0;
+ for (int j = 0; j < GetSize(sig_s); j++) {
+ if (swizzle[j] == -1) {
+ // const 0.
+ } else if (swizzle[j] == -2) {
+ // const 1.
+ idx |= 1 << j;
+ } else {
+ if (i & 1 << swizzle[j])
+ idx |= 1 << j;
+ }
+ }
+ log_assert(!nonzero_idx.count(idx));
+ nonzero_idx.insert(idx);
+ new_sig_y.append(sig_y.extract(idx * width, width));
+ }
+
+ if (new_sig_s.size() == sig_s.size() && sig_s.size() > 0)
+ return;
+
+ log(" New ctrl vector for %s cell %s: %s\n", cell->type.c_str(), cell->name.c_str(), log_signal(new_sig_s));
+ did_something = true;
+ total_count++;
+
+ for (int i = 0; i < (1 << GetSize(sig_s)); i++) {
+ if (!nonzero_idx.count(i)) {
+ SigSpec slice = sig_y.extract(i * width, width);
+ module->connect(slice, Const(State::S0, width));
+ assign_map.add(slice, Const(State::S0, width));
+ }
+ }
+
+ if (new_sig_s.size() == 0)
+ {
+ module->connect(new_sig_y, cell->getPort(ID::A));
+ assign_map.add(new_sig_y, cell->getPort(ID::A));
+ module->remove(cell);
+ }
+ else
+ {
+ cell->setPort(ID::S, new_sig_s);
+ cell->setPort(ID::Y, new_sig_y);
+ cell->parameters[ID::S_WIDTH] = RTLIL::Const(new_sig_s.size());
+ }
+ }
+
+ bool opt_mux_bits(RTLIL::Cell *cell)
+ {
+ SigSpec sig_a = assign_map(cell->getPort(ID::A));
+ SigSpec sig_b;
+ SigSpec sig_y = assign_map(cell->getPort(ID::Y));
+ int width = GetSize(sig_y);
+
+ if (cell->type != ID($bmux))
+ sig_b = assign_map(cell->getPort(ID::B));
- std::vector<RTLIL::SigBit> new_sig_y;
RTLIL::SigSig old_sig_conn;
- std::vector<std::vector<RTLIL::SigBit>> consolidated_in_tuples;
- std::map<std::vector<RTLIL::SigBit>, RTLIL::SigBit> consolidated_in_tuples_map;
+ dict<SigSpec, SigBit> consolidated_in_tuples;
+ std::vector<int> swizzle;
- for (int i = 0; i < int(sig_y.size()); i++)
+ for (int i = 0; i < width; i++)
{
- std::vector<RTLIL::SigBit> in_tuple;
+ SigSpec in_tuple;
bool all_tuple_bits_same = true;
- in_tuple.push_back(sig_a.at(i));
- for (int j = i; j < int(sig_b.size()); j += int(sig_a.size())) {
- if (sig_b.at(j) != sig_a.at(i))
+ in_tuple.append(sig_a[i]);
+ for (int j = i; j < GetSize(sig_a); j += width) {
+ in_tuple.append(sig_a[j]);
+ if (sig_a[j] != in_tuple[0])
+ all_tuple_bits_same = false;
+ }
+ for (int j = i; j < GetSize(sig_b); j += width) {
+ in_tuple.append(sig_b[j]);
+ if (sig_b[j] != in_tuple[0])
all_tuple_bits_same = false;
- in_tuple.push_back(sig_b.at(j));
}
if (all_tuple_bits_same)
{
- old_sig_conn.first.append(sig_y.at(i));
- old_sig_conn.second.append(sig_a.at(i));
+ old_sig_conn.first.append(sig_y[i]);
+ old_sig_conn.second.append(sig_a[i]);
+ continue;
}
- else if (consolidated_in_tuples_map.count(in_tuple))
+
+ auto it = consolidated_in_tuples.find(in_tuple);
+ if (it == consolidated_in_tuples.end())
{
- old_sig_conn.first.append(sig_y.at(i));
- old_sig_conn.second.append(consolidated_in_tuples_map.at(in_tuple));
+ consolidated_in_tuples[in_tuple] = sig_y[i];
+ swizzle.push_back(i);
}
else
{
- consolidated_in_tuples_map[in_tuple] = sig_y.at(i);
- consolidated_in_tuples.push_back(in_tuple);
- new_sig_y.push_back(sig_y.at(i));
+ old_sig_conn.first.append(sig_y[i]);
+ old_sig_conn.second.append(it->second);
}
}
- if (new_sig_y.size() != sig_y.size())
+ if (GetSize(swizzle) != width)
{
log(" Consolidated identical input bits for %s cell %s:\n", cell->type.c_str(), cell->name.c_str());
- log(" Old ports: A=%s, B=%s, Y=%s\n", log_signal(cell->getPort(ID::A)),
- log_signal(cell->getPort(ID::B)), log_signal(cell->getPort(ID::Y)));
-
- cell->setPort(ID::A, RTLIL::SigSpec());
- for (auto &in_tuple : consolidated_in_tuples) {
- RTLIL::SigSpec new_a = cell->getPort(ID::A);
- new_a.append(in_tuple.at(0));
- cell->setPort(ID::A, new_a);
+ if (cell->type != ID($bmux)) {
+ log(" Old ports: A=%s, B=%s, Y=%s\n", log_signal(cell->getPort(ID::A)),
+ log_signal(cell->getPort(ID::B)), log_signal(cell->getPort(ID::Y)));
+ } else {
+ log(" Old ports: A=%s, Y=%s\n", log_signal(cell->getPort(ID::A)),
+ log_signal(cell->getPort(ID::Y)));
}
- cell->setPort(ID::B, RTLIL::SigSpec());
- for (int i = 1; i <= cell->getPort(ID::S).size(); i++)
- for (auto &in_tuple : consolidated_in_tuples) {
- RTLIL::SigSpec new_b = cell->getPort(ID::B);
- new_b.append(in_tuple.at(i));
- cell->setPort(ID::B, new_b);
+ if (swizzle.empty()) {
+ module->remove(cell);
+ } else {
+ SigSpec new_sig_a;
+ for (int i = 0; i < GetSize(sig_a); i += width)
+ for (int j: swizzle)
+ new_sig_a.append(sig_a[i+j]);
+ cell->setPort(ID::A, new_sig_a);
+
+ if (cell->type != ID($bmux)) {
+ SigSpec new_sig_b;
+ for (int i = 0; i < GetSize(sig_b); i += width)
+ for (int j: swizzle)
+ new_sig_b.append(sig_b[i+j]);
+ cell->setPort(ID::B, new_sig_b);
}
- cell->parameters[ID::WIDTH] = RTLIL::Const(new_sig_y.size());
- cell->setPort(ID::Y, new_sig_y);
+ SigSpec new_sig_y;
+ for (int j: swizzle)
+ new_sig_y.append(sig_y[j]);
+ cell->setPort(ID::Y, new_sig_y);
+
+ cell->parameters[ID::WIDTH] = RTLIL::Const(GetSize(swizzle));
+
+ if (cell->type != ID($bmux)) {
+ log(" New ports: A=%s, B=%s, Y=%s\n", log_signal(cell->getPort(ID::A)),
+ log_signal(cell->getPort(ID::B)), log_signal(cell->getPort(ID::Y)));
+ } else {
+ log(" New ports: A=%s, Y=%s\n", log_signal(cell->getPort(ID::A)),
+ log_signal(cell->getPort(ID::Y)));
+ }
+ }
- log(" New ports: A=%s, B=%s, Y=%s\n", log_signal(cell->getPort(ID::A)),
- log_signal(cell->getPort(ID::B)), log_signal(cell->getPort(ID::Y)));
log(" New connections: %s = %s\n", log_signal(old_sig_conn.first), log_signal(old_sig_conn.second));
+ module->connect(old_sig_conn);
+
+ did_something = true;
+ total_count++;
+ }
+ return swizzle.empty();
+ }
+
+ bool opt_demux_bits(RTLIL::Cell *cell) {
+ SigSpec sig_a = assign_map(cell->getPort(ID::A));
+ SigSpec sig_y = assign_map(cell->getPort(ID::Y));
+ int width = GetSize(sig_a);
+
+ RTLIL::SigSig old_sig_conn;
+
+ dict<SigBit, int> handled_bits;
+ std::vector<int> swizzle;
+
+ for (int i = 0; i < width; i++)
+ {
+ if (sig_a[i] == State::S0)
+ {
+ for (int j = i; j < GetSize(sig_y); j += width)
+ {
+ old_sig_conn.first.append(sig_y[j]);
+ old_sig_conn.second.append(State::S0);
+ }
+ continue;
+ }
+ auto it = handled_bits.find(sig_a[i]);
+ if (it == handled_bits.end())
+ {
+ handled_bits[sig_a[i]] = i;
+ swizzle.push_back(i);
+ }
+ else
+ {
+ for (int j = 0; j < GetSize(sig_y); j += width)
+ {
+ old_sig_conn.first.append(sig_y[i+j]);
+ old_sig_conn.second.append(sig_y[it->second+j]);
+ }
+ }
+ }
+
+ if (GetSize(swizzle) != width)
+ {
+ log(" Consolidated identical input bits for %s cell %s:\n", cell->type.c_str(), cell->name.c_str());
+ log(" Old ports: A=%s, Y=%s\n", log_signal(cell->getPort(ID::A)),
+ log_signal(cell->getPort(ID::Y)));
+
+ if (swizzle.empty()) {
+ module->remove(cell);
+ } else {
+ SigSpec new_sig_a;
+ for (int j: swizzle)
+ new_sig_a.append(sig_a[j]);
+ cell->setPort(ID::A, new_sig_a);
+
+ SigSpec new_sig_y;
+ for (int i = 0; i < GetSize(sig_y); i += width)
+ for (int j: swizzle)
+ new_sig_y.append(sig_y[i+j]);
+ cell->setPort(ID::Y, new_sig_y);
+
+ cell->parameters[ID::WIDTH] = RTLIL::Const(GetSize(swizzle));
+
+ log(" New ports: A=%s, Y=%s\n", log_signal(cell->getPort(ID::A)),
+ log_signal(cell->getPort(ID::Y)));
+ }
+
+ log(" New connections: %s = %s\n", log_signal(old_sig_conn.first), log_signal(old_sig_conn.second));
module->connect(old_sig_conn);
did_something = true;
total_count++;
}
+ return swizzle.empty();
}
OptReduceWorker(RTLIL::Design *design, RTLIL::Module *module, bool do_fine) :
@@ -309,20 +575,31 @@ struct OptReduceWorker
// merge identical inputs on $mux and $pmux cells
- std::vector<RTLIL::Cell*> cells;
-
- for (auto &it : module->cells_)
- if ((it.second->type == ID($mux) || it.second->type == ID($pmux)) && design->selected(module, it.second))
- cells.push_back(it.second);
-
- for (auto cell : cells)
+ for (auto cell : module->selected_cells())
{
+ if (!cell->type.in(ID($mux), ID($pmux), ID($bmux), ID($demux)))
+ continue;
+
// this optimization is to aggressive for most coarse-grain applications.
// but we always want it for multiplexers driving write enable ports.
- if (do_fine || mem_wren_sigs.check_any(assign_map(cell->getPort(ID::Y))))
- opt_mux_bits(cell);
+ if (do_fine || mem_wren_sigs.check_any(assign_map(cell->getPort(ID::Y)))) {
+ if (cell->type == ID($demux)) {
+ if (opt_demux_bits(cell))
+ continue;
+ } else {
+ if (opt_mux_bits(cell))
+ continue;
+ }
+ }
+
+ if (cell->type.in(ID($mux), ID($pmux)))
+ opt_pmux(cell);
+
+ if (cell->type == ID($bmux))
+ opt_bmux(cell);
- opt_mux(cell);
+ if (cell->type == ID($demux))
+ opt_demux(cell);
}
}
diff --git a/passes/opt/wreduce.cc b/passes/opt/wreduce.cc
index aaad28ef0..08ab6de6f 100644
--- a/passes/opt/wreduce.cc
+++ b/passes/opt/wreduce.cc
@@ -30,6 +30,7 @@ struct WreduceConfig
{
pool<IdString> supported_cell_types;
bool keepdc = false;
+ bool mux_undef = false;
WreduceConfig()
{
@@ -83,7 +84,7 @@ struct WreduceWorker
SigBit ref = sig_a[i];
for (int k = 0; k < GetSize(sig_s); k++) {
- if ((config->keepdc || (ref != State::Sx && sig_b[k*GetSize(sig_a) + i] != State::Sx)) && ref != sig_b[k*GetSize(sig_a) + i])
+ if ((config->keepdc || !config->mux_undef || (ref != State::Sx && sig_b[k*GetSize(sig_a) + i] != State::Sx)) && ref != sig_b[k*GetSize(sig_a) + i])
goto no_match_ab;
if (sig_b[k*GetSize(sig_a) + i] != State::Sx)
ref = sig_b[k*GetSize(sig_a) + i];
@@ -479,6 +480,9 @@ struct WreducePass : public Pass {
log(" Do not change the width of memory address ports. Use this options in\n");
log(" flows that use the 'memory_memx' pass.\n");
log("\n");
+ log(" -mux_undef\n");
+ log(" remove 'undef' inputs from $mux, $pmux and $_MUX_ cells\n");
+ log("\n");
log(" -keepdc\n");
log(" Do not optimize explicit don't-care values.\n");
log("\n");
@@ -500,6 +504,10 @@ struct WreducePass : public Pass {
config.keepdc = true;
continue;
}
+ if (args[argidx] == "-mux_undef") {
+ config.mux_undef = true;
+ continue;
+ }
break;
}
extra_args(args, argidx, design);
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-10 13:08:37 +0000