1berry/ruby
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Allow pass special constants to the write barrier

Browse Source 
Some GC implementations want to always know when an object is written to,
even if the written value is a special constant. Checking special constants
in rb_obj_written was a micro-optimization that made assumptions about
the GC implementation.
This commit is contained in:
Peter Zhu 2025-06-02 16:31:28 -04:00
parent 5f247416b6
commit ea8b53a539
Notes: git 2025-06-03 16:04:39 +00:00 
Merged: https://github.com/ruby/ruby/pull/13497
4 changed files with 6 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
gc/default/default.c
View File

@ -6006,9 +6006,10 @@ rb_gc_impl_writebarrier(void *objspace_ptr, VALUE a, VALUE b)
if (RGENGC_CHECK_MODE) {
if (SPECIAL_CONST_P(a)) rb_bug("rb_gc_writebarrier: a is special const: %"PRIxVALUE, a);
if (SPECIAL_CONST_P(b)) rb_bug("rb_gc_writebarrier: b is special const: %"PRIxVALUE, b);
}
if (SPECIAL_CONST_P(b)) return;
GC_ASSERT(RB_BUILTIN_TYPE(a) != T_NONE);
GC_ASSERT(RB_BUILTIN_TYPE(a) != T_MOVED);
GC_ASSERT(RB_BUILTIN_TYPE(a) != T_ZOMBIE);

2
gc/mmtk/mmtk.c
View File

@ -750,6 +750,8 @@ rb_gc_impl_writebarrier(void *objspace_ptr, VALUE a, VALUE b)
{
struct MMTk_ractor_cache *cache = rb_gc_get_ractor_newobj_cache();
if (SPECIAL_CONST_P(b)) return;
mmtk_object_reference_write_post(cache->mutator, (MMTk_ObjectReference)a);
}

2
include/ruby/internal/abi.h
View File

@ -24,7 +24,7 @@
* In released versions of Ruby, this number is not defined since teeny
* versions of Ruby should guarantee ABI compatibility.
*/
#define RUBY_ABI_VERSION 1
#define RUBY_ABI_VERSION 2
/* Windows does not support weak symbols so ruby_abi_version will not exist
* in the shared library. */

4
include/ruby/internal/gc.h
View File

@ -785,9 +785,7 @@ rb_obj_written(
RGENGC_LOGGING_OBJ_WRITTEN(a, oldv, b, filename, line);
#endif
if (!RB_SPECIAL_CONST_P(b)) {
rb_gc_writebarrier(a, b);
}
rb_gc_writebarrier(a, b);
return a;
}