This adds support for `$check` cells in chformal and adds a `-lower`
mode which converts `$check` cells into `$assert` etc. cells with a
`$print` cell to output the `$check` message.
Uses the regex below to search (using vscode):
^\t\tlog\("(.{10,}(?<!\\n)|.{81,}\\n)"\);
Finds any log messages double indented (which help messages are)
and checks if *either* there are is no newline character at the end,
*or* the number of characters before the newline is more than 80.
The initial list of hits was generated with the codespell command
below, and each hit was evaluated and fixed manually while taking
context into consideration.
DIRS="kernel/ frontends/ backends/ passes/ techlibs/"
DIRS="${DIRS} libs/ezsat/ libs/subcircuit"
codespell $DIRS -S *.o -L upto,iff,thru,synopsys,uint
More hits were found by looking through comments and strings manually.
o Not all derived methods were marked 'override', but it is a great
feature of C++11 that we should make use of.
o While at it: touched header files got a -*- c++ -*- for emacs to
provide support for that language.
o use YS_OVERRIDE for all override keywords (though we should probably
use the plain keyword going forward now that C++11 is established)
