fixmag.py

py/fixmag.py

Repairs the library path on every use line in a magic cell hierarchy.

python3 ../tech/py/fixmag.py ../design/<LIB>/<CELL>.mag      # make fixmag

A .mag file references a child cell as

use MY_CHILD  MY_CHILD_0 ../SOME_LIB

and the third field is a path that magic has to resolve. When a cell is moved between libraries, or a layout is assembled from cells that came from several places, those paths go stale and magic silently loads the wrong cell or none at all.

The script reads the cell, and for every use looks for <cellname>.mag in any sibling directory (../*/). Exactly one hit rewrites the library field to that directory. More than one hit is an error, reported and left alone, since guessing between two cells with the same name would be worse than leaving it broken. It then recurses into every child it resolved and rewrites those too.

Changed lines are printed as Old: / New: pairs, and only files that actually contain use lines are rewritten.

JNW_TR_SKY130A and JNW_ATR_SKY130A are in an exclude list: those are shared standard cell libraries reached through a symlink, and must not be rewritten from inside an IP.

Note that this writes in place with no dry run, so commit before running it.