Adopted lazy encoding for name attrs
This one is interesting in that we don't just encode to a buffer, but
need to express the concatenation of did + name somehow. Fortunately we
can still leverage the cat circuitry by setting data_count=-2:
- LFSR_TAG_NAME -+-> cat(fromleb128(did), name)
- LFSR_TAG_REG -+
- LFSR_TAG_DIR -+
- LFSR_TAG_STICKYNOTE -'
This does break our shrub estimate for name attrs (currently names have
no technical limit), which would be an issue, but we just happen to never
commit names to shrubs.
In theory you _could_ accurately estimate name attrs if you limited
names to <=(2^15)-5, but I figured this wouldn't be worth the extra code
cost in LFSR_RATTR_NAME__... Especially since it would just go unused...
Saves a nice bit of code, though no stack since we currently don't
allocate any names on the hot-path (lfsr_file_truncate):
code stack ctx
before: 35580 2440 636
after: 35472 (-0.3%) 2440 (+0.0%) 636 (+0.0%)
Note this does _not_ include LFSR_TAG_BOOKMARK, which only contains the
did and can avoid a stack allocation if encoded as a single leb128 attr.
Though breaking up the LFSR_TAG_NAME types does risk a more complicated
switch-case-table...
This commit is contained in:
Christopher Haster