zah 3b47a689cf Remove the use of usrToCell in gcMark [backport:1.2] (#17709) ... * Remove the use of usrToCell in gcMark [backport:1.2] Recently, we've discovered a GC crash resulting from inlining of the memory allocation procs that allowed the compiler to avoid maintaining any references to the "user pointer" on the stack. Instead, a "cell pointer" appeared there and all field accesses were performed with adjusted offsets. This interfered with the ability of the GC to mark the correct cell in the conservative stack scans which lead to premature collection of objects. More details here: af69b3ceae This commit closes another theoretical loophole that may lead to the same problem. If a short proc is accessing both the object and its reference count in a short sequence of instructions, the compiler may be enticed to reduce the number of registers being used by storing only a single pointer to the object and using offsets when reading and writing fields. A perfectly good strategy would be to store only the cell pointer, so the reference count updates can be performed without applying offsets. Accessing the fields of the object requires offsets anyway, but these can be adjusted at compile-time without any loss. Following this strategy will lead to the same problem of marking a wrong cell during the conservative stack scan, leading to premature collection. The problem is avoided by not using `usrToCell` in `gcMark`. Since the cell discovery logic can already handle interior pointers, the user pointers don't need to be adjusted for the GC to function correctly.		2021-04-14 12:10:01 +02:00
..
mm	styleCheck: Fix some inconsistent identifiers (#16177)	2020-12-21 09:41:56 -08:00
alloc.nim	fixes #16214 [backport] (#16252)	2020-12-04 17:47:41 +01:00
ansi_c.nim	system/excpt: let the OS handle termination on signal (#16712)	2021-02-19 00:29:21 -08:00
arc.nim	Replace double backticks with single backticks - Part 1 out of ~6 (#17205)	2021-02-28 23:08:12 -08:00
arithm.nim	use lowercase --define switches (#17283)	2021-03-07 12:08:41 +01:00
arithmetics.nim	Replace double backticks with single backticks - Part 1 out of ~6 (#17205)	2021-02-28 23:08:12 -08:00
assertions.nim	fixes #17033 [backport:1.4] (#17061)	2021-02-17 11:00:03 +01:00
assign.nim	followup for #16717: minimized example + improved comment (#16721)	2021-01-15 01:09:58 +01:00
atomics.nim	[docs minor] remove unicode in docs comments (#16267)	2020-12-06 05:51:29 +01:00
avltree.nim	make AVL tree node part of the memory regions; fixes hard to reproduce channel crashes	2017-01-31 13:08:47 +01:00
basic_types.nim	Replace double backticks with single backticks - Part 1 out of ~6 (#17205)	2021-02-28 23:08:12 -08:00
bitmasks.nim	ARC now capable of custom extra alignment. Ref, closure and seq support. (#15697)	2020-10-28 14:00:49 +01:00
cellseqs_v1.nim	more checking for --gc:arc, no need for valgrind (#14467)	2020-05-29 12:08:17 +02:00
cellseqs_v2.nim	arc allocation method aligned (#15588)	2020-10-19 14:50:06 +02:00
cellsets.nim	cleaned up the internal documentation (#17524)	2021-03-26 16:27:55 +01:00
cgprocs.nim	Initial version of the hot-code reloading support for native targets (#10729)	2019-02-26 15:48:55 +01:00
channels_builtin.nim	rename channels to channels_builtin (#17330)	2021-03-12 13:04:32 +01:00
chcks.nim	[os:standalone]fix #14011 (#17564)	2021-03-29 17:54:28 +02:00
comparisons.nim	implement RFCs/294 ; disallow enum <=> enum conversion (#16351)	2021-04-03 07:15:21 +02:00
countbits_impl.nim	follow up #17539 (#17548)	2021-03-29 09:11:07 +08:00
cyclebreaker.nim	ORC: prepare for another patent-pending optimization (#15996)	2020-11-18 22:31:06 +01:00
deepcopy.nim	ARC now capable of custom extra alignment. Ref, closure and seq support. (#15697)	2020-10-28 14:00:49 +01:00
dollars.nim	Replace double backticks with single backticks - Part 1 out of ~6 (#17205)	2021-02-28 23:08:12 -08:00
dyncalls.nim	Genode platform fixes (#17521)	2021-04-09 16:29:10 +02:00
embedded.nim	ensure the avr example keeps compiling (#17663)	2021-04-07 13:40:57 +02:00
exceptions.nim	Replace double backticks with single backticks - Part 1 out of ~6 (#17205)	2021-02-28 23:08:12 -08:00
excpt.nim	IC: green tests (#17311)	2021-03-19 16:53:38 +01:00
fatal.nim	fix #16499 (#16514)	2021-01-04 18:27:58 +01:00
formatfloat.nim	Revert "printing float values will have one more digit. (#13276) [backport]" (#13363)	2020-02-08 09:30:24 +01:00
gc.nim	Remove the use of usrToCell in gcMark [backport:1.2] (#17709)	2021-04-14 12:10:01 +02:00
gc2.nim	followup #17225: simplify code after removing gc2, generational (#17242)	2021-03-03 13:37:42 +01:00
gc_common.nim	fixes #17647 (#17667)	2021-04-07 23:26:53 +02:00
gc_hooks.nim	gc:destructors progress	2019-09-16 23:54:31 +02:00
gc_interface.nim	fixes #13881	2020-05-12 15:46:24 +02:00
gc_ms.nim	Remove the use of usrToCell in gcMark [backport:1.2] (#17709)	2021-04-14 12:10:01 +02:00
gc_regions.nim	styleCheck: Fix some inconsistent identifiers (#16177)	2020-12-21 09:41:56 -08:00
hti.nim	allow old styled RTTI for arc/orc (#15331)	2020-09-16 14:57:01 +02:00
inclrtl.nim	remove all uses of condsyms symbols defined prior to bootstrap nim 0.20.0 (#16918)	2021-02-17 09:32:36 +01:00
indexerrors.nim	[other] better error message for IndexError for empty containers (#11476)	2019-06-11 14:34:21 +02:00
integerops.nim	fixes #14209 [backport:1.2] (#14213)	2020-05-05 00:48:13 +02:00
io.nim	use lowercase --define switches (#17283)	2021-03-07 12:08:41 +01:00
iterators.nim	further progress on rst roles & directives (fix #17646) (#17659)	2021-04-08 19:00:14 +02:00
iterators_1.nim	Change stdlib imports to use std prefix in most examples (#17202)	2021-02-28 13:17:19 -08:00
jssys.nim	[backport:1.4] JS cstring null fixes (#16979)	2021-02-11 17:04:32 +01:00
memalloc.nim	[docs]close #12580 (#17549)	2021-03-28 20:21:27 -07:00
memory.nim	remove all uses of condsyms symbols defined prior to bootstrap nim 0.20.0 (#16918)	2021-02-17 09:32:36 +01:00
memtracker.nim	addQuitProc => addExitProc (#16765)	2021-01-22 19:51:11 +01:00
mmdisp.nim	fix #15617(fix compilation failure on -d:useMalloc --gc:none) (#17555)	2021-03-30 20:15:14 +02:00
nimscript.nim	Replace double backticks with single backticks - Part 2 out of ~6 (#17206)	2021-02-28 23:15:26 -08:00
orc.nim	Replace double backticks with single backticks - Part 2 out of ~6 (#17206)	2021-02-28 23:15:26 -08:00
osalloc.nim	add OpenBSD MAP_STACK for coroutines (#14353)	2020-05-16 21:56:52 +02:00
platforms.nim	Add 32-bit RISC-V support (#16231)	2020-12-03 17:33:42 +01:00
profiler.nim	Give better error message when profiler and memProfiler used at same time (#9948)	2018-12-19 10:02:20 +01:00
repr.nim	remove all uses of condsyms symbols defined prior to bootstrap nim 0.20.0 (#16918)	2021-02-17 09:32:36 +01:00
repr_v2.nim	repr_v2 improvements (#14992)	2020-07-15 22:04:15 +02:00
reprjs.nim	fix #16025 repr now consistent: does not insert trailing newline (#16034)	2020-11-19 12:12:51 -08:00
seqs_v2.nim	ARC now capable of custom extra alignment. Ref, closure and seq support. (#15697)	2020-10-28 14:00:49 +01:00
seqs_v2_reimpl.nim	arc allocation method aligned (#15588)	2020-10-19 14:50:06 +02:00
setops.nim	better setops docs (#16236)	2020-12-03 14:47:44 +01:00
sets.nim	close #11330 sets uses optimized countSetBits (#17334)	2021-03-22 00:36:48 +01:00
stacktraces.nim	Replace double backticks with single backticks - Part 2 out of ~6 (#17206)	2021-02-28 23:15:26 -08:00
strmantle.nim	remove all uses of condsyms symbols defined prior to bootstrap nim 0.20.0 (#16918)	2021-02-17 09:32:36 +01:00
strs_v2.nim	rename prepareStrMutation to prepareMutation (#17235)	2021-03-03 08:08:52 +08:00
syslocks.nim	use lowercase --define switches (#17283)	2021-03-07 12:08:41 +01:00
sysspawn.nim	styleCheck: Fix some inconsistent identifiers (#16177)	2020-12-21 09:41:56 -08:00
sysstr.nim	followup #17225: simplify code after removing gc2, generational (#17242)	2021-03-03 13:37:42 +01:00
threadlocalstorage.nim	Fix #17299, fix setAffinity for android (#17574)	2021-03-30 08:05:37 +02:00
threads.nim	Replace double backticks with single backticks - Part 2 out of ~6 (#17206)	2021-02-28 23:15:26 -08:00
timers.nim	miscellaneous bug fixes (#13291)	2020-01-30 10:54:50 +01:00
widestrs.nim	use single backtick (#17133)	2021-02-21 00:27:39 -08:00