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dfflibmap: simpler handling of cells with inverted data input polarity

This commit is contained in:
Iztok Jeras 2026-06-23 23:15:23 +02:00
parent bc133317f1
commit d0365d9e68
1 changed files with 4 additions and 16 deletions
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20
passes/techmap/dfflibmap.cc
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@ -293,17 +293,11 @@ static void find_cell_dff(std::vector<const LibertyAst *> cells, IdString cell_t
if (!parse_next_state(cell, ff->find("next_state"), cell_next_pin, cell_next_pol, cell_enable_pin, cell_enable_pol) || (has_enable && (cell_enable_pin.empty() || cell_enable_pol != enapol)))
continue;
if (has_reset && !cell_next_pol) {
// next_state is negated
// we later propagate this inversion to the output,
// which requires the negation of the reset value
rstval = !rstval;
}
if (has_reset && rstval == false) {
if (has_reset && rstval != cell_next_pol) {
if (!parse_pin(cell, ff->find("clear"), cell_rst_pin, cell_rst_pol) || cell_rst_pol != rstpol)
continue;
}
if (has_reset && rstval == true) {
if (has_reset && rstval == cell_next_pol) {
if (!parse_pin(cell, ff->find("preset"), cell_rst_pin, cell_rst_pol) || cell_rst_pol != rstpol)
continue;
}
@ -552,17 +546,11 @@ static void find_cell_dlatch(std::vector<const LibertyAst *> cells, IdString cel
if (!parse_pin(cell, latch->find("data_in"), cell_data_pin, cell_data_pol))
continue;
if (has_reset && !cell_data_pol) {
// data_in is negated
// we later propagate this inversion to the output,
// which requires the negation of the reset value
rstval = !rstval;
}
if (has_reset && rstval == false) {
if (has_reset && rstval != cell_data_pol) {
if (!parse_pin(cell, latch->find("clear"), cell_rst_pin, cell_rst_pol) || cell_rst_pol != rstpol)
continue;
}
if (has_reset && rstval == true) {
if (has_reset && rstval == cell_data_pol) {
if (!parse_pin(cell, latch->find("preset"), cell_rst_pin, cell_rst_pol) || cell_rst_pol != rstpol)
continue;
}