Replace repetitive C code in "gc.c" and "vfasl.c" with an
implementation using a little "Parenthe-C" language, which is a
somewhat declarative description of object tracing. From that
descrition, we generate different kinds of tracing functions, such as
the copy function or the sweep function.
The little language is still bascially C, just with parentheses and
parameterization that is much better than trying to use the C
preprocessor. (The "mkgc.ss" file includes the compiler from
Parenthe-C to C.)
Besides replacing existing code, we also generate a new traversal to
implement `compute-object-sizes`. Finally, the GC can now perform a
fused `collect` and `compute-object-sizes` in a single traversal.
Also improve the way that locked objects are detected during GC. This
can make a significant difference (on the order of 10-20% for a full
collection) when locked objects are long-lived.
original commit: de1f5c41d729ac75822a1f1e633ec6d042c883dc
For a collect rendezvous, call the collect-notify handler in
the main thread if it is active. A collect-notify handler can
then make sure the main thread is active and try again, if
that's useful to an application.
original commit: 0bc286e81827f029dd02a3627a192edd053b3b91
When a proceudre starts with a trap check, move the check to the very
beginning, even before checking the argument count. That way, event
detection can turn into a compact jump to an event handler, instead of
inserting a general call to `$event` in the procedure body.
original commit: 06b12d505698a2378734689370bb9e0f8eda06b9
loadability without actually loading; also, support for unregistering
guarded objects.
- improved error reporting for library compilation-instance errors:
now including the name of the object file from which the "wrong"
compilation instance was loaded, if it was loaded from (or compiled
to) an object file and the original importing library, if it was
previously loaded from an object file due to a library import.
syntax.ss, 7.ss, interpret.ss,
8.ms, root-experr*
- removed situation and for-input? arguments from $make-load-binary,
since the only consumer always passes 'load and #f.
7.ss,
scheme.c
- $separate-eval now prints the stderr and stdout of the subprocess
to help in diagnosing separate-eval and separate-compile issues.
mat.ss
- added unregister-guardian, which can be used to unregister
the unressurected objects registered with any guardian. guardian?
can be used to distinguish guardian procedures from other objects.
cp0.ss, cmacros.ss, cpnanopass.ss, ftype.ss, primdata.ss,
prims.ss,
gcwrapper.c, prim.c, externs.h,
4.ms, primvars.ms
release_notes.stex
smgmt.stex, threads.stex
- added verify-loadability. given a situation (visit, revisit,
or load) and zero or more pathnames (each of which may be optionally
paired with a library search path), verity-loadability checks
whether the set of object files named by those pathnames and any
additional object files required by library requirements in the
given situation can be loaded together. it raises an exception
in each case where actually attempting to load the files would
raise an exception and additionally in cases where loading files
would result in the compilation or loading of source files in
place of the object files. if the check is successful,
verity-loadability returns an unspecified value. in either case,
although portions of the object files are read, none of the
information read from the object files is retained, and none of
the object code is read, so there are no side effects other than
the file operations and possibly the raising of an exception.
library and program info records are now moved to the top of each
object file produced by one of the file compilation routines,
just after recompile info, with a marker to allow verity-loadability
to stop reading once it reads all such records. this change is
not entirely backward compatible; the repositioning of the records
can be detected by a call to list-library made from a loaded file
before the definition of one or more libraries. it is fully
backward compatible for typical library files that contain a
single library definition and nothing else. adding this feature
required changes to the object-file format and corresponding
changes in the compiler and library manager. it also required
moving cross-library optimization information from library/ct-info
records (which verity-loadability must read) to the invoke-code
for each library (which verity-loadability does not read) to
avoid reading and permanently associating record-type descriptors
in the code with their uids.
compile.ss, syntax.ss, expand-lang.ss, primdata.ss, 7.ss,
7.ms, misc.ms, root-experr*, patch*,
system.stex, release_notes.stex
- fixed a bug that bit only with the compiler compiled at
optimize-level 2: add-library/rt-records was building a library/ct-info
wrapper rather than a library/rt-info wrapper.
compile.ss
- fixed a bug in visit-library that could result in an indefinite
recursion: it was not checking to make sure the call to $visit
actually added compile-time info to the libdesc record. it's not
clear, however, whether the libdesc record can be missing
compile-time information on entry to visit-library, so the code
that calls $visit (and now checks for compile-time information
having been added) might not be reachable. ditto for
revisit-library.
syntax.ss
syntax.ss, primdata.ss,
7.ms, root-experr*, patch*,
system.stex, release_notes.stex
- added some argument-error checks for library-directories and
library-extensions, and fixed up the error messages a bit.
syntax.ss,
7.ms, root-experr*
- compile-whole-program now inserts the program record into the
object file for the benefit of verify-loadability.
syntax.ss,
7.ms, root-experr*
- changed 'loading' import-notify messages to the more precise
'visiting' or 'revisiting' in a couple of places.
syntax.ss,
7.ms, 8.ms
original commit: b911ed47190727b0e1d6a88c0e473d1757accdcd
On x86_64, a POPCNT instruction is usually available, and it can speed
up `fxpopcount` operations by a factor of 2-3.
Since POPCNT isn't always available, code using `fxpopcount` is
compiled to a call to a generic implementation. The linker substitutes
a POPCNT instruction when it determines at runtime that POPCNT is
available.
Some measurements on a 2018 MacBook Pro (2.7 GHz Core i7) using the
program below:
popcnt = this implementation, POPCNT discovered
nocnt = this implementation, POPCNT considered unavailable
optcnt = compile to use POPCNT directly (no linker work)
cpcnt = compile to inlined generic (no linker work, no POPCNT)
Since the generic implementation is always a 64-bit popcount, it's not
as good as an inlined version for `fxpopcount32`, but otherwise the
link-edit approach to POPCNT works well:
fxpopcount fxpopcount32
popcnt: 0.098s
nocnt: 0.284s
optcnt 0.109s [slower means noise?]
cpcnt: 0.279s 0.188s
(optimize-level 3)
(time
(let loop ([v #f] [i 100000000])
(if (fx= i 0)
v
(loop (fxpopcount i) (fx- i 1)))))
original commit: 5f090e509f8fe5edc777ed9f0463b20c2e571336
reclaimed by the collector and must be released explicitly by the
programmer via (profile-release-counters).
pdhtml.ss, primdata.ss,
globals.h, externs.h, fasl.c, prim5.c, prim.c, alloc.c, scheme.c,
misc.ms,
release_notes.stex, system.stex
original commit: 68e20f721618dbaf4c1634067c2bee24a493a750
Also adds `get-initial-thread`, since threa values are useful with
`compute-size[-increments]`.
Changes the compiler to inline `weak-pair?` and `ephemeron-pair?`,
since that provides better performance for `compute-size-increments`.
original commit: 57d0cc13f8e932972cba3837b4f54e9c86786091
The `object-references` function is intended to support debugging of
memory leaks by providing a mapping from each live object to the
object that retained it.
original commit: 61f6602b7e6c388c529f3c5995dcf71a7c42e005
sizes of pathnames produced by expansion of tilde (home-directory)
prefixes by replacing S_pathname, S_pathname_impl, and S_homedir
with S_malloc_pathname, which always mallocs space for the result.
one thread-safety issue involved the use of static strings for expanded
pathnames and affected various file-system operations. the other
affected the file open routines and involved use of the incoming
pathname while deactivated. the incoming pathname is sometimes if not
always a pointer into a Scheme bytevector, which can be overwritten if a
collection occurs while the thread is deactivated. the size limitation
corresponded to the use of the static strings, which were limited to
PATH_MAX bytes. (PATH_MAX typically isn't actually the maximum path
length in contemporary operating systems.) eliminated similar issues
for wide pathnames under Windows by adding S_malloc_wide_pathname.
consumers of the old routines have been modified to use the new
routines and to free the result strings. the various file operations
now consistently treat a pathname with an unresolvable home directory
as a pathname that happens to start with a tilde. eliminated unused
foreign-symbol binding of "(cs)pathname" to S_pathname.
io.c, externs.h, new_io.c, prim5.c, scheme.c, prim.c
- various places where a call to close or gzclose was retried when
the close operation was interrupted no longer do so, since this can
cause problems when another thread has reallocated the same file
descriptor.
new_io.c
- now using vcvarsall type x86_amd64 rather than amd64 when the
former appears to supported and the latter does not, as is the
case with VS Express 2015.
c/Mf-a6nt, c/Mf-ta6nt
- commented out one of the thread mats that consistently causes
indefinite delays under Windows and OpenBSD due to starvation.
thread.ms
- increased wait time for a couple of subprocess responses
6.ms
- added call to collector to close files opened during iconv mats
specifically for when mats are run under Windows with no iconv dll.
io.ms
original commit: ad44924307c576eb2fc92e7958afe8b615a7f48b
