Short-circuit commonly called witness functions so that they only
execute in debug builds, and remove equivalent guards from mutex
functions.  This avoids pointless code execution in
witness_assert_lockless(), which is typically called twice per
allocation/deallocation function invocation.

Inline commonly called witness functions so that optimized builds can
completely remove calls as dead code.

Fix in place huge reallocation to update the chunk counters that are
used for triggering gdump profiles.

b2c0d632 (Add witness, a simple online
locking validator.) caused a broad propagation of tsd throughout the
internal API, but tsd_fetch() was designed to fail prior to tsd
bootstrapping.  Fix this by splitting tsd_t into non-nullable tsd_t and
nullable tsdn_t, and modifying all internal APIs that do not critically
rely on tsd to take nullable pointers.  Furthermore, add the
tsd_booted_get() function so that tsdn_fetch() can probe whether tsd
bootstrapping is complete and return NULL if not.  All dangerous
conversions of nullable pointers are tsdn_tsd() calls that assert-fail
on invalid conversion.

This is a broader application of optimizations to malloc() and free() in
f4a0f32d (Fast-path improvement:
reduce # of branches and unnecessary operations.).

This resolves #321.

If the OS overcommits:
- Commit all mappings in pages_map() regardless of whether the caller
  requested committed memory.
- Linux-specific: Specify MAP_NORESERVE to avoid
  unfortunate interactions with heuristic overcommit mode during
  fork(2).

This resolves #193.

This makes the numbers reported in the leak report summary closely match
those reported by jeprof.

This resolves #356.

This resolves #367.

Link libjemalloc against librt if clock_gettime(2) is in librt rather
than libc, as for versions of glibc prior to 2.17.

This resolves #349.

Split arena_choose() into arena_[i]choose() and use arena_ichoose() for
arena lookup during internal allocation.  This fixes huge_palloc() so
that it always succeeds during extent node allocation.

This regression was introduced by
66cd9535 (Do not allocate metadata via
non-auto arenas, nor tcaches.).

Depending on virtual memory resource limits, it is necessary to attempt
allocating three maximally sized objects to trigger OOM rather than just
two, since the maximum supported size is slightly less than half the
total virtual memory address space.

This fixes a test failure that was introduced by
0c516a00 (Make *allocx() size class
overflow behavior defined.).

This resolves #379.

Fix witness to clear its list of owned mutexes in the child if
platform-specific malloc_mutex code re-initializes mutexes rather than
unlocking them.

This assures that side effects of internal allocation don't impact
tests.

Reset large curruns to 0 during arena reset.

Do not increase huge ndalloc stats during arena reset.

This regression was caused by 66cd9535
(Do not allocate metadata via non-auto arenas, nor tcaches.).

This resolves #375.

This makes it possible to discard all of an arena's allocations in a
single operation.

This resolves #146.

This assures that all internally allocated metadata come from the
first opt_narenas arenas, i.e. the automatically multiplexed arenas.

Change test-related mangling to simplify symbol filtering.

The following commands can be used to detect missing/obsolete symbol
mangling, with the caveat that the full set of symbols is based on the
union of symbols generated by all configurations, some of which are
platform-specific:

./autogen.sh --enable-debug --enable-prof --enable-lazy-lock
make all tests
nm -a lib/libjemalloc.a src/*.jet.o \
  |grep " [TDBCR] " \
  |awk '{print $3}' \
  |sed -e 's/^\(je_\|jet_\(n_\)\?\)\([a-zA-Z0-9_]*\)/\3/g' \
  |LC_COLLATE=C sort -u \
  |grep -v \
   -e '^\(malloc\|calloc\|posix_memalign\|aligned_alloc\|realloc\|free\)$' \
   -e '^\(m\|r\|x\|s\|d\|sd\|n\)allocx$' \
   -e '^mallctl\(\|nametomib\|bymib\)$' \
   -e '^malloc_\(stats_print\|usable_size\|message\)$' \
   -e '^\(memalign\|valloc\)$' \
   -e '^__\(malloc\|memalign\|realloc\|free\)_hook$' \
   -e '^pthread_create$' \
  > /tmp/private_symbols.txt

Add 4 missing symbols

Also remove tautological cassert(config_debug) calls.

This fixes a compilation error caused by
b2c0d632 (Add witness, a simple online
locking validator.).

This resolves #375.

Fix a compilation error that occurs if Valgrind is not enabled.  This
regression was caused by b2c0d632 (Add
witness, a simple online locking validator.).

This resolves #358.