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Added read-enable to memory model

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This commit is contained in:
Clifford Wolf 2015-09-25 12:23:11 +02:00
parent ec92c89659
commit 924d9d6e86
17 changed files with 157 additions and 76 deletions
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52
passes/memory/memory_dff.cc
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@ -31,6 +31,7 @@ struct MemoryDffWorker
vector<Cell*> dff_cells;
dict<SigBit, SigBit> invbits;
dict<SigBit, int> sigbit_users_count;
dict<SigSpec, Cell*> mux_cells_a, mux_cells_b;
MemoryDffWorker(Module *module) : module(module), sigmap(module) { }
@ -150,16 +151,44 @@ struct MemoryDffWorker
if (sigbit_users_count[bit] > 1)
goto skip_ff_after_read_merging;
if (find_sig_before_dff(sig_data, clk_data, clk_polarity, true) && clk_data != RTLIL::SigSpec(RTLIL::State::Sx))
if (mux_cells_a.count(sig_data) || mux_cells_b.count(sig_data))
{
disconnect_dff(sig_data);
cell->setPort("\\CLK", clk_data);
cell->setPort("\\DATA", sig_data);
cell->parameters["\\CLK_ENABLE"] = RTLIL::Const(1);
cell->parameters["\\CLK_POLARITY"] = RTLIL::Const(clk_polarity);
cell->parameters["\\TRANSPARENT"] = RTLIL::Const(0);
log("merged data $dff to cell.\n");
return;
bool enable_invert = mux_cells_a.count(sig_data);
Cell *mux = enable_invert ? mux_cells_a.at(sig_data) : mux_cells_b.at(sig_data);
SigSpec check_q = sigmap(mux->getPort(enable_invert ? "\\B" : "\\A"));
sig_data = sigmap(mux->getPort("\\Y"));
for (auto bit : sig_data)
if (sigbit_users_count[bit] > 1)
goto skip_ff_after_read_merging;
if (find_sig_before_dff(sig_data, clk_data, clk_polarity, true) && clk_data != RTLIL::SigSpec(RTLIL::State::Sx) && sig_data == check_q)
{
disconnect_dff(sig_data);
cell->setPort("\\CLK", clk_data);
cell->setPort("\\EN", enable_invert ? module->LogicNot(NEW_ID, mux->getPort("\\S")) : mux->getPort("\\S"));
cell->setPort("\\DATA", sig_data);
cell->parameters["\\CLK_ENABLE"] = RTLIL::Const(1);
cell->parameters["\\CLK_POLARITY"] = RTLIL::Const(clk_polarity);
cell->parameters["\\TRANSPARENT"] = RTLIL::Const(0);
log("merged data $dff with rd enable to cell.\n");
return;
}
}
else
{
if (find_sig_before_dff(sig_data, clk_data, clk_polarity, true) && clk_data != RTLIL::SigSpec(RTLIL::State::Sx))
{
disconnect_dff(sig_data);
cell->setPort("\\CLK", clk_data);
cell->setPort("\\EN", State::S1);
cell->setPort("\\DATA", sig_data);
cell->parameters["\\CLK_ENABLE"] = RTLIL::Const(1);
cell->parameters["\\CLK_POLARITY"] = RTLIL::Const(clk_polarity);
cell->parameters["\\TRANSPARENT"] = RTLIL::Const(0);
log("merged data $dff to cell.\n");
return;
}
}
skip_ff_after_read_merging:;
@ -169,6 +198,7 @@ struct MemoryDffWorker
clk_addr != RTLIL::SigSpec(RTLIL::State::Sx))
{
cell->setPort("\\CLK", clk_addr);
cell->setPort("\\EN", State::S1);
cell->setPort("\\ADDR", sig_addr);
cell->parameters["\\CLK_ENABLE"] = RTLIL::Const(1);
cell->parameters["\\CLK_POLARITY"] = RTLIL::Const(clk_polarity);
@ -191,6 +221,10 @@ struct MemoryDffWorker
for (auto cell : module->cells()) {
if (cell->type == "$dff")
dff_cells.push_back(cell);
if (cell->type == "$mux") {
mux_cells_a[sigmap(cell->getPort("\\A"))] = cell;
mux_cells_b[sigmap(cell->getPort("\\B"))] = cell;
}
if (cell->type == "$not" || cell->type == "$_NOT_" || (cell->type == "$logic_not" && GetSize(cell->getPort("\\A")) == 1)) {
SigSpec sig_a = cell->getPort("\\A");
SigSpec sig_y = cell->getPort("\\Y");