Rename ADDRESS_SANITIZER -> ZSTD_ADDRESS_SANITIZER and same for
MEMORY_SANITIZER. Also set it to 0/1 instead of checking for defined.
This allows the user to override ASAN/MSAN detection for platforms that
don't support it.
This clarifies operator precedence, and quiets cppcheck in
the Kernel Test Robot. I think this is a slight bonus to
readability, so I am accepting the suggestion.
Even if the discrepancies are at the moment benign, it's probably better to
standardize on using the one true initializer, rather than trying (and failing)
to correctly duplicate its behavior.
Rewrite ZSTD_createCDict_advanced() as a wrapper around
ZSTD_createCDict_advanced2(). Evaluate whether to use DDSS mode *after* fully
resolving cparams. If not, fall back.
Rather than restrict our temp chain table to 2 ** chainLog entries, this
commit uses all available space to reach further back to gather longer
chains to pack into the DDSS chain table.
Rather than interleave all of the chain table entries, tying each entry's
position to the corresponding position in the input, this commit changes the
layout so that all the entries in a single chain are laid out next to each
other. The last entry in the hash table's bucket for this hash is now a packed
pointer of position + length of this chain.
This cannot be merged as written, since it allocates temporary memory inside
ZSTD_dedicatedDictSearch_lazy_loadDictionary().
Previously, if DDSS was enabled on a CCtx and a dictionary was inserted into
the CCtx, the CCtx MatchState would be filled as a DDSS struct, causing
segfaults etc. This changes the check to use whether the MatchState is marked
as using the DDSS (which is only ever set for CDict MatchStates), rather than
looking at the CCtxParams.
Entries in the hashTable chain cache aren't subject to the same aliasing that
the circular chain table is subject to. As such, we don't need to stop when we
cross the chain limit. We can delve deeper. :)
This caused us to double-search the first position and fail to search the
last position in the chain, slowing down search and making it less effective.
This makes it clear that not only is the feature allowed here, we're actually
using it, as opposed to the CCtxParam field, in which it's enabled, but we may
or may not be using it.
