tile.h is included by a large part of the project, but the definitions
in sys/mman.h are only needed by the implementation code inside tile.c
so this reduces project wide include dependencies.
Removal of unnecessary function call indirection into TileStoreFree()
since TiFree() is has multiple implementation already and we can
customize TiFree() directly as required.
Move the function definitions into the tile.h to they are visible to
compiler during code generation to consider inline potential.
This has made global 'Tile *TileStoreFreeList' more visible.
database corruption discovered recently that was uncovered by a
commit on Jan. 31 and is caused by DBMergeNMTiles0() using a
freed tile (reported in github issue #404).
the TiAlloc() and TiFree() code path.
The rationale of the changes:
Performing the one-time initialization check (first call to
mmapTileStore()) for every TiAlloc() is unnecessary if the decision code
is reworked to allow NULL pointers to exist in the computation and still
make the correct decision.
Use of 'unsigned long' for pointer arithmetic is not compatible with _WIN64
compiler model LLP64. Changed to 'pointertype'.
The computations addition/subtraction/greater-than were performed
multiple times. Seemed a convoulted method when a single operation
should be good enough.
The use of a single-linked-list with HEAD and TAIL does not make sense.
My gut is telling me that for the purpose of memory allocation a LIFO is
better as a free-and-reuse of the most recently freed item is more likely
to already be in the CPU cache and the oldest freed item is more likely
to have been evicted from CPU cache. So given the use of a custom
allocator and no support to reclaim/compact or manage fragmentation
other factor didn't carry any weight.
Technically TiAlloc() returns undefined memory and the first action of
the caller is to write new values, but the point remains that write is
more likely to cause eviction of something else from cache with the
original FIFO scheme.
Due to the free list use during TiFree() there is a write to each alloc
which will make the cache-line hotter in the cache (less likely to have
been evicted) when using LIFO scheme than FIFO scheme.
Further more the use of HEAD and TAIL had a far more complex
TileStoreFree() than was necessary even for such a list. A 4 line
method turned into 7 with multiple conditions tested when branching.
The TileStoreFreeList/TileStoreFreeList_end were public symbols which may
also impact the freedom the compiler has to optimise around them.
Using LIFO single-linked-list resulted in the removal of
TileStoreFreeList_end and associated simplification.
Use of 'static' for the methods mmapTileStore() and getTimeFromTileStore()
these are not public API so adding the 'static' give the compiler a hint
these methods maybe inlined as they are not accessile from outside this
compliation unit.
The -O3 assembly result looks quite healthy in achieving the original
goal of instruction and branch reductions with the compiler able to
inline all 3 methods into a single TiAlloc().
All naked access to `ti_client` now uses the function-like-macro
to encapsulate this action. This macro existed before this just
makes all sites utilize it.
Added additional INT and PTR variants to remove the programmer
load on thinking about casing and casts polluting the point
of use. So the use now looks cleaner.
Equivalent prototypes:
void TiSetClient(Tile*, ClientData)
void TiSetClientINT(Tile*, intptr_t) /* pointertype */
void TiSetClientPTR(Tile*, void*)
ClientData TiGetClient(Tile*)
intptr_t TiGetClientINT(Tile*) /* pointertype */
void *TiGetClientPTR(Tile*)
This commit makes the code (mostly) C99-compatible, enabling to compile
it without the -Wno-error=implicit-function-declaration flag. This
way, Magic becomes usable on arm64 architectures, specifically on Apple
computers with M1/M2 SoC.
Conflicts:
VERSION
calma/Depend
cif/Depend
cmwind/Depend
commands/Depend
database/Depend
dbwind/Depend
debug/Depend
drc/Depend
ext2sim/Depend
ext2spice/Depend
extflat/Depend
extract/Depend
garouter/Depend
gcr/Depend
graphics/Depend
grouter/Depend
irouter/Depend
lef/Depend
lisp/Depend
mzrouter/Depend
netmenu/Depend
plot/Depend
plow/Depend
resis/Depend
router/Depend
select/Depend
sim/Depend
tcltk/Depend
textio/Depend
tiles/Depend
utils/Depend
windows/Depend
wiring/Depend
Merged recent changes from master branch into bplane branch. Testing the
bplane implementation which has about a 5x improvement in extraction times
for large layouts, which is significant enough to move ahead with the bplane
implementation; however, the bplane implementation has not been thoroughly
vetted yet, so it will remain a branch until such time that it has been
validated.
Darryl L. Miles
R. Timothy Edwards
Alessandro De Laurenzis