In order to enable replay of traces on machines that do not use FreeType
as the native font system, we need to convert a type42 font into something
similar. Currently the fallback is just to select a font with the same
name - this ignores weight and slant, and many other details.
Kerning is quite frequent, that is to apply a horizontal but no vertical
offset to a glyph. For instance by discarding the vertical coordinate
where it remains the same and only encoding the horizontal offset we
reduce the file size by ~12.5% when tracing poppler.
If we fail to add the glyph cache (presumably because the font is in
error) do not leak the allocation. As this occurs for every single glyph
string, the leak can grow very quickly and mask the original bug.
After diverting the pointers to accommodate lazy decompressing of the
source, the bytecode pointer was left pointing to the original location
that had already been freed - thus passing an invalid block to FreeType
and unsurprisingly then, blowing up.
Hook into the scanner to write out binary version of the tokenized
objects -- note we bind executable names (i.e. check to see if is an
operator and substitute the name with an operator -- this breaks
overloading of operators by scripts).
By converting scripts to a binary form, they are more compact and
execute faster:
firefox-world-map.trace 526850146 bytes
bound.trace 275187755 bytes
[ # ] backend test min(s) median(s) stddev. count
[ 0] null bound 34.481 34.741 0.68% 3/3
[ 1] null firefox-world-map 89.635 89.716 0.19% 3/3
[ 0] drm bound 79.304 79.350 0.61% 3/3
[ 1] drm firefox-world-map 135.380 135.475 0.58% 3/3
[ 0] image bound 95.819 96.258 2.85% 3/3
[ 1] image firefox-world-map 156.889 156.935 1.36% 3/3
[ 0] xlib bound 539.130 550.220 1.40% 3/3
[ 1] xlib firefox-world-map 596.244 613.487 1.74% 3/3
This trace has a lot of complex paths and the use of binary floating point
reduces the file size by about 50%, with a commensurate reduction in scan
time and significant reduction in operator lookup overhead. Note that this
test is still IO/CPU bound on my i915 with its pitifully slow flash...
These can be reasonably large and persist for long times due to the
font holdover caches, so manually swap them out to save space on tiny
swapless machines.
As an aide to tiny swapless systems write the rarely used bytes that
define type42 fonts into a deleted file and mmap them back into our
address space.
Seeing unexpected time inside pixman composite is quite disturbing when
trying to track down the apparent slowness in some benchmarks. Remove one
source of this artefact by simply memcpy'ing pixel data when trivial.
The glyph advance cache was only enabled for glyph indices < 256,
causing a large number of misses for non-ASCII text. Improve this by
simply applying the modulus of the index to select the cache slot - which
may cause some glyph advances to be overwritten and re-queried, but
improves the hit rate.
Bah, the compiler failed to do its IPA correctly and wrongly complained
about potential use of uninitialised out-params guarded by the return
value. Silence them!
Frequently to push an object onto the stack all we need is to simply
perform the struct copy - so inline it and only call the out-of-line
function if we need to enlarge the stack.
The relational comparison operators can now compare strings vs names
by content as well as performing automatic type promotions on the
numeric types. For other types relational comparisons succeeed
only if the values compare equal according to the eq operator, and
put the interpreter into a type-error state otherwise.
The eq operator would only work for some types and put the
interpreter in an error state if passed objects it didn't
know how to compare. It would also not compare strings
by value nor allow strings to be compared to names.
This patch makes any two objects comparable.
Add a CairoScript interpreter library and use it to replay the test output
for the CairoScript backend. The library is also used by the currently
standalone Sphinx debugger [git://anongit.freedesktop.org/~ickle/sphinx].
The syntax/operator semantics are not yet finalized, but are expected to
mature before the next stable release.
