[PATCH 0/5] RFC: Overhaul of diagnostics (v2)
Wed Sep 23 13:36:00 GMT 2015
On Tue, 22 Sep 2015, David Malcolm wrote:
> The drawback is that it could bloat the ad-hoc table. Can the ad-hoc
> table ever get smaller, or does it only ever get inserted into?
It only ever grows.
> An idea I had is that we could stash short ranges directly into the 32
> bits of location_t, by offsetting the per-column-bits somewhat.
It's certainly worth an experiment: let's say you restrict yourself to
tokens less than 8 characters, you need an additional 3 bits (using one
value, e.g. zero, as the escape value). That leaves 20 bits for the line
numbers (for the normal 8 bit columns), which might be enough for most
single-file compilations. For LTO compilation this often won't be enough.
> My plan is to investigate the impact these patches have on the time and
> memory consumption of the compiler,
When you do so, make sure you're also measuring an LTO compilation with
debug info of something big (firefox). I know that we already had issues
with the size of the linemap data in the past for these cases (probably
when we added columns).
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