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Working for 1 bit

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This commit is contained in:
Eddie Hung 2019-03-22 17:46:49 -07:00
parent 46753cf89f
commit 03d108cd1f
1 changed files with 49 additions and 11 deletions
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60
passes/techmap/shregmap.cc
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@ -104,12 +104,23 @@ struct ShregmapTechXilinx7 : ShregmapTech
{
for (const auto &i : module->cells_) {
auto cell = i.second;
if (cell->type != "$shiftx") continue;
if (cell->getParam("\\Y_WIDTH") != 1) continue;
int j = 0;
for (auto bit : sigmap(cell->getPort("\\A")))
sigbit_to_shiftx_offset[bit] = std::make_pair(cell, j++);
log_assert(j == cell->getParam("\\A_WIDTH").as_int());
if (cell->type == "$shiftx") {
if (cell->getParam("\\Y_WIDTH") != 1) continue;
int j = 0;
for (auto bit : sigmap(cell->getPort("\\A")))
sigbit_to_shiftx_offset[bit] = std::make_pair(cell, j++);
log_assert(j == cell->getParam("\\A_WIDTH").as_int());
}
else if (cell->type == "$pmux") {
if (cell->getParam("\\WIDTH") != 1) continue;
auto a_bit = sigmap(cell->getPort("\\A")).as_bit();
sigbit_to_shiftx_offset[a_bit] = std::make_pair(cell, 0);
int j = cell->getParam("\\S_WIDTH").as_int();
for (auto bit : sigmap(cell->getPort("\\B")))
sigbit_to_shiftx_offset[bit] = std::make_pair(cell, j--);
log_assert(j == 0);
}
}
}
@ -118,8 +129,12 @@ struct ShregmapTechXilinx7 : ShregmapTech
auto it = sigbit_to_shiftx_offset.find(bit);
if (it == sigbit_to_shiftx_offset.end())
return;
if (cell && cell->type == "$shiftx" && port == "\\A")
return;
if (cell) {
if (cell->type == "$shiftx" && port == "\\A")
return;
if (cell->type == "$pmux" && (port == "\\A" || port == "\\B"))
return;
}
sigbit_to_shiftx_offset.erase(it);
}
@ -166,8 +181,15 @@ struct ShregmapTechXilinx7 : ShregmapTech
log_assert(shiftx);
// Only map if $shiftx exclusively covers the shift register
if (GetSize(taps) != shiftx->getParam("\\A_WIDTH").as_int())
return false;
if (shiftx->type == "$shiftx") {
if (GetSize(taps) != shiftx->getParam("\\A_WIDTH").as_int())
return false;
}
else if (shiftx->type == "$pmux") {
if (GetSize(taps) != shiftx->getParam("\\S_WIDTH").as_int() + 1)
return false;
}
else log_abort();
return true;
}
@ -193,9 +215,25 @@ struct ShregmapTechXilinx7 : ShregmapTech
newcell->setPort("\\E", cell->getPort("\\E"));
Cell* shiftx = it->second.first;
RTLIL::SigSpec l_wire;
if (shiftx->type == "$shiftx") {
l_wire = shiftx->getPort("\\B");
}
else if (shiftx->type == "$pmux") {
// Create a new encoder, out of a $pmux, that takes
// the existing pmux's 'S' input and transforms it
// back into a binary value
int clog2taps = ceil(log2(taps.size()));
RTLIL::SigSpec b_port;
for (int i = shiftx->getParam("\\S_WIDTH").as_int(); i > 0; i--)
b_port.append(RTLIL::Const(i, clog2taps));
l_wire = cell->module->addWire(NEW_ID, clog2taps);
cell->module->addPmux(NEW_ID, RTLIL::Const(0, clog2taps), b_port, shiftx->getPort("\\S"), l_wire);
}
else log_abort();
newcell->setPort("\\L", shiftx->getPort("\\B"));
newcell->setPort("\\Q", shiftx->getPort("\\Y"));
newcell->setPort("\\L", l_wire);
cell->module->remove(shiftx);