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yosys/passes/pmgen/xilinx_dsp.cc

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/*
* yosys -- Yosys Open SYnthesis Suite
*
* Copyright (C) 2012 Clifford Wolf <clifford@clifford.at>
* 2019 Eddie Hung <eddie@fpgeh.com>
*
* 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 <deque>
USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN
#include "passes/pmgen/xilinx_dsp_pm.h"
#include "passes/pmgen/xilinx_dsp_CREG_pm.h"
#include "passes/pmgen/xilinx_dsp_cascade_pm.h"
static Cell* addDsp(Module *module) {
Cell *cell = module->addCell(NEW_ID, ID(DSP48E1));
cell->setParam(ID(ACASCREG), 0);
cell->setParam(ID(ADREG), 0);
cell->setParam(ID(A_INPUT), Const("DIRECT"));
cell->setParam(ID(ALUMODEREG), 0);
cell->setParam(ID(AREG), 0);
cell->setParam(ID(BCASCREG), 0);
cell->setParam(ID(B_INPUT), Const("DIRECT"));
cell->setParam(ID(BREG), 0);
cell->setParam(ID(CARRYINREG), 0);
cell->setParam(ID(CARRYINSELREG), 0);
cell->setParam(ID(CREG), 0);
cell->setParam(ID(DREG), 0);
cell->setParam(ID(INMODEREG), 0);
cell->setParam(ID(MREG), 0);
cell->setParam(ID(OPMODEREG), 0);
cell->setParam(ID(PREG), 0);
cell->setParam(ID(USE_MULT), Const("NONE"));
cell->setParam(ID(USE_SIMD), Const("ONE48"));
cell->setParam(ID(USE_DPORT), Const("FALSE"));
cell->setPort(ID(D), Const(0, 25));
cell->setPort(ID(INMODE), Const(0, 5));
cell->setPort(ID(ALUMODE), Const(0, 4));
cell->setPort(ID(OPMODE), Const(0, 7));
cell->setPort(ID(CARRYINSEL), Const(0, 3));
cell->setPort(ID(ACIN), Const(0, 30));
cell->setPort(ID(BCIN), Const(0, 18));
cell->setPort(ID(PCIN), Const(0, 48));
cell->setPort(ID(CARRYIN), Const(0, 1));
return cell;
}
void xilinx_simd_pack(Module *module, const std::vector<Cell*> &selected_cells)
{
std::deque<Cell*> simd12_add, simd12_sub;
std::deque<Cell*> simd24_add, simd24_sub;
for (auto cell : selected_cells) {
if (!cell->type.in(ID($add), ID($sub)))
continue;
SigSpec Y = cell->getPort(ID(Y));
if (!Y.is_chunk())
continue;
if (!Y.as_chunk().wire->get_strpool_attribute(ID(use_dsp)).count("simd"))
continue;
if (GetSize(Y) > 25)
continue;
SigSpec A = cell->getPort(ID(A));
SigSpec B = cell->getPort(ID(B));
if (GetSize(Y) <= 13) {
if (GetSize(A) > 12)
continue;
if (GetSize(B) > 12)
continue;
if (cell->type == ID($add))
simd12_add.push_back(cell);
else if (cell->type == ID($sub))
simd12_sub.push_back(cell);
}
else if (GetSize(Y) <= 25) {
if (GetSize(A) > 24)
continue;
if (GetSize(B) > 24)
continue;
if (cell->type == ID($add))
simd24_add.push_back(cell);
else if (cell->type == ID($sub))
simd24_sub.push_back(cell);
}
else
log_abort();
}
auto f12 = [module](SigSpec &AB, SigSpec &C, SigSpec &P, SigSpec &CARRYOUT, Cell *lane) {
SigSpec A = lane->getPort(ID(A));
SigSpec B = lane->getPort(ID(B));
SigSpec Y = lane->getPort(ID(Y));
A.extend_u0(12, lane->getParam(ID(A_SIGNED)).as_bool());
B.extend_u0(12, lane->getParam(ID(B_SIGNED)).as_bool());
AB.append(A);
C.append(B);
if (GetSize(Y) < 13)
Y.append(module->addWire(NEW_ID, 13-GetSize(Y)));
else
log_assert(GetSize(Y) == 13);
P.append(Y.extract(0, 12));
CARRYOUT.append(Y[12]);
};
auto g12 = [&f12,module](std::deque<Cell*> &simd12) {
while (simd12.size() > 1) {
SigSpec AB, C, P, CARRYOUT;
Cell *lane1 = simd12.front();
simd12.pop_front();
Cell *lane2 = simd12.front();
simd12.pop_front();
Cell *lane3 = nullptr;
Cell *lane4 = nullptr;
if (!simd12.empty()) {
lane3 = simd12.front();
simd12.pop_front();
if (!simd12.empty()) {
lane4 = simd12.front();
simd12.pop_front();
}
}
log("Analysing %s.%s for Xilinx DSP SIMD12 packing.\n", log_id(module), log_id(lane1));
Cell *cell = addDsp(module);
cell->setParam(ID(USE_SIMD), Const("FOUR12"));
// X = A:B
// Y = 0
// Z = C
cell->setPort(ID(OPMODE), Const::from_string("0110011"));
log_assert(lane1);
log_assert(lane2);
f12(AB, C, P, CARRYOUT, lane1);
f12(AB, C, P, CARRYOUT, lane2);
if (lane3) {
f12(AB, C, P, CARRYOUT, lane3);
if (lane4)
f12(AB, C, P, CARRYOUT, lane4);
else {
AB.append(Const(0, 12));
C.append(Const(0, 12));
P.append(module->addWire(NEW_ID, 12));
CARRYOUT.append(module->addWire(NEW_ID, 1));
}
}
else {
AB.append(Const(0, 24));
C.append(Const(0, 24));
P.append(module->addWire(NEW_ID, 24));
CARRYOUT.append(module->addWire(NEW_ID, 2));
}
log_assert(GetSize(AB) == 48);
log_assert(GetSize(C) == 48);
log_assert(GetSize(P) == 48);
log_assert(GetSize(CARRYOUT) == 4);
cell->setPort(ID(A), AB.extract(18, 30));
cell->setPort(ID(B), AB.extract(0, 18));
cell->setPort(ID(C), C);
cell->setPort(ID(P), P);
cell->setPort(ID(CARRYOUT), CARRYOUT);
if (lane1->type == ID($sub))
cell->setPort(ID(ALUMODE), Const::from_string("0011"));
module->remove(lane1);
module->remove(lane2);
if (lane3) module->remove(lane3);
if (lane4) module->remove(lane4);
module->design->select(module, cell);
}
};
g12(simd12_add);
g12(simd12_sub);
auto f24 = [module](SigSpec &AB, SigSpec &C, SigSpec &P, SigSpec &CARRYOUT, Cell *lane) {
SigSpec A = lane->getPort(ID(A));
SigSpec B = lane->getPort(ID(B));
SigSpec Y = lane->getPort(ID(Y));
A.extend_u0(24, lane->getParam(ID(A_SIGNED)).as_bool());
B.extend_u0(24, lane->getParam(ID(B_SIGNED)).as_bool());
C.append(A);
AB.append(B);
if (GetSize(Y) < 25)
Y.append(module->addWire(NEW_ID, 25-GetSize(Y)));
else
log_assert(GetSize(Y) == 25);
P.append(Y.extract(0, 24));
CARRYOUT.append(module->addWire(NEW_ID)); // TWO24 uses every other bit
CARRYOUT.append(Y[24]);
};
auto g24 = [&f24,module](std::deque<Cell*> &simd24) {
while (simd24.size() > 1) {
SigSpec AB;
SigSpec C;
SigSpec P;
SigSpec CARRYOUT;
Cell *lane1 = simd24.front();
simd24.pop_front();
Cell *lane2 = simd24.front();
simd24.pop_front();
log("Analysing %s.%s for Xilinx DSP SIMD24 packing.\n", log_id(module), log_id(lane1));
Cell *cell = addDsp(module);
cell->setParam(ID(USE_SIMD), Const("TWO24"));
// X = A:B
// Y = 0
// Z = C
cell->setPort(ID(OPMODE), Const::from_string("0110011"));
log_assert(lane1);
log_assert(lane2);
f24(AB, C, P, CARRYOUT, lane1);
f24(AB, C, P, CARRYOUT, lane2);
log_assert(GetSize(AB) == 48);
log_assert(GetSize(C) == 48);
log_assert(GetSize(P) == 48);
log_assert(GetSize(CARRYOUT) == 4);
cell->setPort(ID(A), AB.extract(18, 30));
cell->setPort(ID(B), AB.extract(0, 18));
cell->setPort(ID(C), C);
cell->setPort(ID(P), P);
cell->setPort(ID(CARRYOUT), CARRYOUT);
if (lane1->type == ID($sub))
cell->setPort(ID(ALUMODE), Const::from_string("0011"));
module->remove(lane1);
module->remove(lane2);
module->design->select(module, cell);
}
};
g24(simd24_add);
g24(simd24_sub);
}
void xilinx_dsp_pack(xilinx_dsp_pm &pm)
{
auto &st = pm.st_xilinx_dsp_pack;
log("Analysing %s.%s for Xilinx DSP packing.\n", log_id(pm.module), log_id(st.dsp));
log_debug("preAdd: %s\n", log_id(st.preAdd, "--"));
log_debug("ffAD: %s %s %s\n", log_id(st.ffAD, "--"), log_id(st.ffADcemux, "--"), log_id(st.ffADrstmux, "--"));
log_debug("ffA2: %s %s %s\n", log_id(st.ffA2, "--"), log_id(st.ffA2cemux, "--"), log_id(st.ffA2rstmux, "--"));
log_debug("ffA1: %s %s %s\n", log_id(st.ffA1, "--"), log_id(st.ffA1cemux, "--"), log_id(st.ffA1rstmux, "--"));
log_debug("ffB2: %s %s %s\n", log_id(st.ffB2, "--"), log_id(st.ffB2cemux, "--"), log_id(st.ffB2rstmux, "--"));
log_debug("ffB1: %s %s %s\n", log_id(st.ffB1, "--"), log_id(st.ffB1cemux, "--"), log_id(st.ffB1rstmux, "--"));
log_debug("ffD: %s %s %s\n", log_id(st.ffD, "--"), log_id(st.ffDcemux, "--"), log_id(st.ffDrstmux, "--"));
log_debug("dsp: %s\n", log_id(st.dsp, "--"));
log_debug("ffM: %s %s %s\n", log_id(st.ffM, "--"), log_id(st.ffMcemux, "--"), log_id(st.ffMrstmux, "--"));
log_debug("postAdd: %s\n", log_id(st.postAdd, "--"));
log_debug("postAddMux: %s\n", log_id(st.postAddMux, "--"));
log_debug("ffP: %s %s %s\n", log_id(st.ffP, "--"), log_id(st.ffPcemux, "--"), log_id(st.ffPrstmux, "--"));
log_debug("overflow: %s\n", log_id(st.overflow, "--"));
Cell *cell = st.dsp;
if (st.preAdd) {
log(" preadder %s (%s)\n", log_id(st.preAdd), log_id(st.preAdd->type));
bool A_SIGNED = st.preAdd->getParam(ID(A_SIGNED)).as_bool();
bool D_SIGNED = st.preAdd->getParam(ID(B_SIGNED)).as_bool();
if (st.sigA == st.preAdd->getPort(ID(B)))
std::swap(A_SIGNED, D_SIGNED);
st.sigA.extend_u0(30, A_SIGNED);
st.sigD.extend_u0(25, D_SIGNED);
cell->setPort(ID(A), st.sigA);
cell->setPort(ID(D), st.sigD);
cell->setPort(ID(INMODE), Const::from_string("00100"));
if (st.ffAD) {
if (st.ffADcemux) {
SigSpec S = st.ffADcemux->getPort(ID(S));
cell->setPort(ID(CEAD), st.ffADcepol ? S : pm.module->Not(NEW_ID, S));
}
else
cell->setPort(ID(CEAD), State::S1);
cell->setParam(ID(ADREG), 1);
}
cell->setParam(ID(USE_DPORT), Const("TRUE"));
pm.autoremove(st.preAdd);
}
if (st.postAdd) {
log(" postadder %s (%s)\n", log_id(st.postAdd), log_id(st.postAdd->type));
SigSpec &opmode = cell->connections_.at(ID(OPMODE));
if (st.postAddMux) {
log_assert(st.ffP);
opmode[4] = st.postAddMux->getPort(ID(S));
pm.autoremove(st.postAddMux);
}
else if (st.ffP && st.sigC == st.sigP)
opmode[4] = State::S0;
else
opmode[4] = State::S1;
opmode[6] = State::S0;
opmode[5] = State::S1;
if (opmode[4] != State::S0) {
if (st.postAddMuxAB == ID(A))
st.sigC.extend_u0(48, st.postAdd->getParam(ID(B_SIGNED)).as_bool());
else
st.sigC.extend_u0(48, st.postAdd->getParam(ID(A_SIGNED)).as_bool());
cell->setPort(ID(C), st.sigC);
}
pm.autoremove(st.postAdd);
}
if (st.overflow) {
log(" overflow %s (%s)\n", log_id(st.overflow), log_id(st.overflow->type));
cell->setParam(ID(USE_PATTERN_DETECT), Const("PATDET"));
cell->setParam(ID(SEL_PATTERN), Const("PATTERN"));
cell->setParam(ID(SEL_MASK), Const("MASK"));
if (st.overflow->type == ID($ge)) {
Const B = st.overflow->getPort(ID(B)).as_const();
log_assert(std::count(B.bits.begin(), B.bits.end(), State::S1) == 1);
// Since B is an exact power of 2, subtract 1
// by inverting all bits up until hitting
// that one hi bit
for (auto &b : B.bits)
if (b == State::S0) b = State::S1;
else if (b == State::S1) {
b = State::S0;
break;
}
B.extu(48);
cell->setParam(ID(MASK), B);
cell->setParam(ID(PATTERN), Const(0, 48));
cell->setPort(ID(OVERFLOW), st.overflow->getPort(ID(Y)));
}
else log_abort();
pm.autoremove(st.overflow);
}
if (st.clock != SigBit())
{
cell->setPort(ID(CLK), st.clock);
auto f = [&pm,cell](SigSpec &A, Cell* ff, Cell* cemux, bool cepol, IdString ceport, Cell* rstmux, bool rstpol, IdString rstport) {
SigSpec D = ff->getPort(ID(D));
SigSpec Q = pm.sigmap(ff->getPort(ID(Q)));
if (!A.empty())
A.replace(Q, D);
if (rstmux) {
SigSpec Y = rstmux->getPort(ID(Y));
SigSpec AB = rstmux->getPort(rstpol ? ID(A) : ID(B));
if (!A.empty())
A.replace(Y, AB);
if (rstport != IdString()) {
SigSpec S = rstmux->getPort(ID(S));
cell->setPort(rstport, rstpol ? S : pm.module->Not(NEW_ID, S));
}
}
else if (rstport != IdString())
cell->setPort(rstport, State::S0);
if (cemux) {
SigSpec Y = cemux->getPort(ID(Y));
SigSpec BA = cemux->getPort(cepol ? ID(B) : ID(A));
SigSpec S = cemux->getPort(ID(S));
if (!A.empty())
A.replace(Y, BA);
cell->setPort(ceport, cepol ? S : pm.module->Not(NEW_ID, S));
}
else
cell->setPort(ceport, State::S1);
for (auto c : Q.chunks()) {
auto it = c.wire->attributes.find(ID(init));
if (it == c.wire->attributes.end())
continue;
for (int i = c.offset; i < c.offset+c.width; i++) {
log_assert(it->second[i] == State::S0 || it->second[i] == State::Sx);
it->second[i] = State::Sx;
}
}
};
if (st.ffA2) {
SigSpec A = cell->getPort(ID(A));
f(A, st.ffA2, st.ffA2cemux, st.ffA2cepol, ID(CEA2), st.ffA2rstmux, st.ffArstpol, ID(RSTA));
if (st.ffA1) {
f(A, st.ffA1, st.ffA1cemux, st.ffA1cepol, ID(CEA1), st.ffA1rstmux, st.ffArstpol, IdString());
cell->setParam(ID(AREG), 2);
cell->setParam(ID(ACASCREG), 2);
}
else {
cell->setParam(ID(AREG), 1);
cell->setParam(ID(ACASCREG), 1);
}
pm.add_siguser(A, cell);
cell->setPort(ID(A), A);
}
if (st.ffB2) {
SigSpec B = cell->getPort(ID(B));
f(B, st.ffB2, st.ffB2cemux, st.ffB2cepol, ID(CEB2), st.ffB2rstmux, st.ffBrstpol, ID(RSTB));
if (st.ffB1) {
f(B, st.ffB1, st.ffB1cemux, st.ffB1cepol, ID(CEB1), st.ffB1rstmux, st.ffBrstpol, IdString());
cell->setParam(ID(BREG), 2);
cell->setParam(ID(BCASCREG), 2);
}
else {
cell->setParam(ID(BREG), 1);
cell->setParam(ID(BCASCREG), 1);
}
pm.add_siguser(B, cell);
cell->setPort(ID(B), B);
}
if (st.ffD) {
SigSpec D = cell->getPort(ID(D));
f(D, st.ffD, st.ffDcemux, st.ffDcepol, ID(CED), st.ffDrstmux, st.ffDrstpol, ID(RSTD));
pm.add_siguser(D, cell);
cell->setPort(ID(D), D);
cell->setParam(ID(DREG), 1);
}
if (st.ffM) {
SigSpec M; // unused
f(M, st.ffM, st.ffMcemux, st.ffMcepol, ID(CEM), st.ffMrstmux, st.ffMrstpol, ID(RSTM));
st.ffM->connections_.at(ID(Q)).replace(st.sigM, pm.module->addWire(NEW_ID, GetSize(st.sigM)));
cell->setParam(ID(MREG), State::S1);
}
if (st.ffP) {
SigSpec P; // unused
f(P, st.ffP, st.ffPcemux, st.ffPcepol, ID(CEP), st.ffPrstmux, st.ffPrstpol, ID(RSTP));
st.ffP->connections_.at(ID(Q)).replace(st.sigP, pm.module->addWire(NEW_ID, GetSize(st.sigP)));
cell->setParam(ID(PREG), State::S1);
}
log(" clock: %s (%s)", log_signal(st.clock), "posedge");
if (st.ffA2) {
log(" ffA2:%s", log_id(st.ffA2));
if (st.ffA1)
log(" ffA1:%s", log_id(st.ffA1));
}
if (st.ffAD)
log(" ffAD:%s", log_id(st.ffAD));
if (st.ffB2) {
log(" ffB2:%s", log_id(st.ffB2));
if (st.ffB1)
log(" ffB1:%s", log_id(st.ffB1));
}
if (st.ffD)
log(" ffD:%s", log_id(st.ffD));
if (st.ffM)
log(" ffM:%s", log_id(st.ffM));
if (st.ffP)
log(" ffP:%s", log_id(st.ffP));
}
log("\n");
SigSpec P = st.sigP;
if (GetSize(P) < 48)
P.append(pm.module->addWire(NEW_ID, 48-GetSize(P)));
cell->setPort(ID(P), P);
pm.blacklist(cell);
}
void xilinx_dsp_packC(xilinx_dsp_CREG_pm &pm)
{
auto &st = pm.st_xilinx_dsp_packC;
log_debug("Analysing %s.%s for Xilinx DSP packing (CREG).\n", log_id(pm.module), log_id(st.dsp));
log_debug("ffC: %s %s %s\n", log_id(st.ffC, "--"), log_id(st.ffCcemux, "--"), log_id(st.ffCrstmux, "--"));
Cell *cell = st.dsp;
if (st.clock != SigBit())
{
cell->setPort(ID(CLK), st.clock);
auto f = [&pm,cell](SigSpec &A, Cell* ff, Cell* cemux, bool cepol, IdString ceport, Cell* rstmux, bool rstpol, IdString rstport) {
SigSpec D = ff->getPort(ID(D));
SigSpec Q = pm.sigmap(ff->getPort(ID(Q)));
if (!A.empty())
A.replace(Q, D);
if (rstmux) {
SigSpec Y = rstmux->getPort(ID(Y));
SigSpec AB = rstmux->getPort(rstpol ? ID(A) : ID(B));
if (!A.empty())
A.replace(Y, AB);
if (rstport != IdString()) {
SigSpec S = rstmux->getPort(ID(S));
cell->setPort(rstport, rstpol ? S : pm.module->Not(NEW_ID, S));
}
}
else if (rstport != IdString())
cell->setPort(rstport, State::S0);
if (cemux) {
SigSpec Y = cemux->getPort(ID(Y));
SigSpec BA = cemux->getPort(cepol ? ID(B) : ID(A));
SigSpec S = cemux->getPort(ID(S));
if (!A.empty())
A.replace(Y, BA);
cell->setPort(ceport, cepol ? S : pm.module->Not(NEW_ID, S));
}
else
cell->setPort(ceport, State::S1);
for (auto c : Q.chunks()) {
auto it = c.wire->attributes.find(ID(init));
if (it == c.wire->attributes.end())
continue;
for (int i = c.offset; i < c.offset+c.width; i++) {
log_assert(it->second[i] == State::S0 || it->second[i] == State::Sx);
it->second[i] = State::Sx;
}
}
};
if (st.ffC) {
SigSpec C = cell->getPort(ID(C));
f(C, st.ffC, st.ffCcemux, st.ffCcepol, ID(CEC), st.ffCrstmux, st.ffCrstpol, ID(RSTC));
pm.add_siguser(C, cell);
cell->setPort(ID(C), C);
cell->setParam(ID(CREG), 1);
}
log(" clock: %s (%s)", log_signal(st.clock), "posedge");
if (st.ffC)
log(" ffC:%s", log_id(st.ffC));
log("\n");
}
pm.blacklist(cell);
}
struct XilinxDspPass : public Pass {
XilinxDspPass() : Pass("xilinx_dsp", "Xilinx: pack resources into DSPs") { }
void help() YS_OVERRIDE
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
log(" xilinx_dsp [options] [selection]\n");
log("\n");
log("Pack input registers (A2, A1, B2, B1, C, D, AD; with optional enable/reset),\n");
log("pipeline registers (M; with optional enable/reset), output registers (P; with\n");
log("optional enable/reset), pre-adder and/or post-adder into Xilinx DSP resources.\n");
log("\n");
log("Multiply-accumulate operations using the post-adder with feedback on the 'C'\n");
log("input will be folded into the DSP. In this scenario only, the 'C' input can be\n");
log("used to override the current accumulation result with a new value, which will\n");
log("be added to the multiplier result to form the next accumulation result.\n");
log("\n");
log("Use of the dedicated 'PCOUT' -> 'PCIN' cascade path is detected for 'P' -> 'C'\n");
log("connections (optionally, where 'P' is right-shifted by 17-bits and used as an\n");
log("input to the post-adder -- a pattern common for summing partial products to\n");
log("implement wide multipliers). Limited support also exists for similar cascading\n");
log("for A and B using '[AB]COUT' -> '[AB]CIN'. Currently, cascade chains are limited\n");
log("to a maximum length of 20 cells, corresponding to the smallest Xilinx 7 Series\n");
log("device.\n");
log("\n");
log("\n");
log("Experimental feature: addition/subtractions less than 12 or 24 bits with the\n");
log("'(* use_dsp=\"simd\" *)' attribute attached to the output wire or attached to\n");
log("the add/subtract operator will cause those operations to be implemented using\n");
log("the 'SIMD' feature of DSPs.\n");
log("\n");
log("Experimental feature: the presence of a `$ge' cell attached to the registered\n");
log("P output implementing the operation \"(P >= <power-of-2>)\" will be transformed\n");
log("into using the DSP48E1's pattern detector feature for overflow detection.\n");
log("\n");
}
void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
{
log_header(design, "Executing XILINX_DSP pass (pack resources into DSPs).\n");
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++)
{
// if (args[argidx] == "-singleton") {
// singleton_mode = true;
// continue;
// }
break;
}
extra_args(args, argidx, design);
for (auto module : design->selected_modules()) {
// Experimental feature: pack $add/$sub cells with
// (* use_dsp48="simd" *) into DSP48E1's using its
// SIMD feature
xilinx_simd_pack(module, module->selected_cells());
// Match for all features ([ABDMP][12]?REG, pre-adder,
// post-adder, pattern detector, etc.) except for CREG
{
xilinx_dsp_pm pm(module, module->selected_cells());
pm.run_xilinx_dsp_pack(xilinx_dsp_pack);
}
// Separating out CREG packing is necessary since there
// is no guarantee that the cell ordering corresponds
// to the "expected" case (i.e. the order in which
// they appear in the source) thus the possiblity
// existed that a register got packed as a CREG into a
// downstream DSP that should have otherwise been a
// PREG of an upstream DSP that had not been visited
// yet
{
xilinx_dsp_CREG_pm pm(module, module->selected_cells());
pm.run_xilinx_dsp_packC(xilinx_dsp_packC);
}
// Lastly, identify and utilise PCOUT -> PCIN,
// ACOUT -> ACIN, and BCOUT-> BCIN dedicated cascade
// chains
{
xilinx_dsp_cascade_pm pm(module, module->selected_cells());
pm.run_xilinx_dsp_cascade();
}
}
}
} XilinxDspPass;
PRIVATE_NAMESPACE_END
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