NUM_IN_PAGE(page->start) will sometimes return a 0 or a 1 depending on
how the alignment of the 40 byte slots work out. This commit uses the
NUM_IN_PAGE function to shift the bitmap down on the first bitmap plane.
Iterating on the first bitmap plane is "special", but this commit allows
us to align object addresses on something besides 40 bytes, and also
eliminates the need to fill guard bits.
This is a follow-up of 86c262541ad07528842d76dab4b9b34bd888d5f4.
CRITICAL_SECTION_START/FINISH are not needed when it's called from an
MJIT worker.
Also, ZALLOC needs to be calloc because ZALLOC may trigger GC, which an
MJIT worker must not do.
This fixes SEGVs like https://github.com/ruby/ruby/runs/2715166621?check_suite_focus=true.
When mjit_recompile is called when mjit_compile is compiling the exact
same iseq (and after it called mjit_capture_cc_entries), iseq->body->jit_unit
is re-created and its cc_entries becomes NULL. Then, when it tries to
lookup cc_entries through iseq->body->jit_unit, it fails.
This changes "test/rubygems/test_case.rb" to "test/rubygems/helper.rb",
and "test/rubygems/test_utilities.rb" to "test/rubygems/utilities.rb".
The two files are a helper for tests, not test files. However, a file
starting with "test_" prefix is handled as a test file directly loaded
by test-unit because Rakefile specifies:
```
t.test_files = FileList['test/**/test_*.rb']
```
Directly loading test/rubygems/test_utilities.rb caused "uninitialized
constant Gem::TestCase". This issue was fixed by
59c682097197fee4052b47e4b4ab86562f3eaa9b, but the fix caused a
"circular require" warning because test_utilities.rb and test_case.rb
are now requiring each other.
Anyway, adding "test_" prefix to a test helper file is confusing, so
this changeset reverts the fix and solve the issue by renaming them.
https://github.com/rubygems/rubygems/commit/6460e018df
We are only iterating over the eden heap so `heap_eden->total_pages`
contains the exact number of pages we need to allocate for.
`heap_allocated_pages` may contain pages in the tomb.
Instead of keeping track of the current bit plane, keep track of the
actual slot when compacting. This means we don't need to re-scan
objects inside the same bit plane when we continue with movement
I'm investigating SEGVs like https://github.com/ruby/ruby/runs/2715166621?check_suite_focus=true.
Because a lot of things are going on on this line, it's hard to identify
the cause, especially because we can't get the core file of the failures.
Therefore I intentionally increased the number of lines for
investigation.
Compiling everything seems to contributed to improving the final
performance in general. MJIT's compilation is slow anyway, especially
when you need to wait for JIT compaction.
This might make sense for short-time benchmarks like Optcarrot with
default parameters, but it didn't give benefits in my local environment.
