riscv
/
yosys
mirror of https://github.com/YosysHQ/yosys.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
11,038 Commits 76 Branches 48 Tags 62 MiB
Commit Graph

4 Commits

Author SHA1 Message Date
Marcelina Kościelnicka 50d532f01c techmap/shift_shiftx: Remove the "shiftx2mux" special path. 
Our techmap rules for $shift and $shiftx cells contained a special path
that aimed to decompose the shift LSB-first instead of MSB-first in
select cases that come up in pmux lowering.  This path was needlessly
overcomplicated and contained bugs.

Instead of doing that, just switch over the main path to iterate
LSB-first (except for the specially-handled MSB for signed shifts
and overflow handling).  This also makes the code consistent with
shl/shr/sshl/sshr cells, which are already decomposed LSB-first.

Fixes #2346.
 2020-08-20 12:44:09 +02:00
Eddie Hung 4c1d3a126d shiftx2mux: fix select out of bounds 2020-02-05 16:41:09 -08:00
Eddie Hung 8d1b736c4f Move from +/shiftx2mux.v into +/techmap.v; cleanup 2020-01-21 15:19:41 -08:00
Eddie Hung 7977574995 New techmap +/shiftx2mux.v which decomposes LSB first; better for ABC 2020-01-21 15:19:41 -08:00