when the allocator can extend the block in place, realloc avoids
the overhead of malloc+memcpy+free. the keys are moved to their
new position with memmove and extended regions are cleared.
Co-authored-by: Claude <noreply@anthropic.com>
saves 40% memory (60 -> 36 bytes) for objects with 1-2 instance
variables, which is common for simple value objects like Point(@x, @y).
the trade-off is one extra reallocation when growing from 2 to 4 IVs,
but this is negligible since reallocations are rare compared to lookups.
Co-authored-by: Claude <noreply@anthropic.com>
dd96afd added const_added hook call to mrb_const_set(), but calling
mrb_funcall_argv() during core initialization (before bootstrapping
completes) fails on bare metal platforms where VM is not fully ready.
skip hook during mrb->bootstrapping phase, matching pattern used in
class.c for method cache clearing.
Co-authored-by: Claude <noreply@anthropic.com>
Replace XML-style markup tags in comments with markdown equivalents:
- <code>...</code> to `...` (inline code)
- <tt>...</tt> to `...` (teletype/monospace)
- <i>...</i> to *...* (italics/emphasis)
- +...+ to `...` (parameter/variable references)
Updated 80+ files across core source, headers, mrbgems, and libraries
to use consistent markdown formatting in documentation comments.
Handled edge cases including special characters like <=> operators.
Co-authored-by: Atlassian Rovo Dev
This commit introduces memory prefetching to the `bsearch_idx` functions
in `src/class.c` and `src/variable.c` to improve performance.
A new macro `MRB_MEM_PREFETCH` is defined in `include/mruby/variable.h`
which uses `__builtin_prefetch` if available.
Co-authored-by: Gemini <gemini@google.com>
This commit optimizes instance variable lookups by replacing the
search algorithm with the same branch-free binary search recently
introduced for method lookups. This improves performance by
avoiding CPU branch mispredictions.
This commit corrects the placement of C-style block comments
for MRB_API functions in src/variable.c. Comments are now
placed directly before each function definition as per standard
documentation practices.
Preserve the original iv_tbl heap layout and allocation pattern, but
switch iv_put to maintain sorted keys and iv_get/iv_del to perform
binary search. This eliminates extra probing overhead, improves
read-heavy lookup performance for small tables, and incurs zero
additional allocations.
Calling `mrb_gc_unregistor()` from `mrb_data_type::dfree` caused a use-after-free deep inside `mrb_close()`.
The impetus to investigate was <https://github.com/mruby/mruby/pull/6342#pullrequestreview-2292747530>.
Currently, when `mrb_close()` is called, all objects are destroyed first.
The process is done heap page by heap page, and when all objects belonging to a heap page are destroyed, the heap page is released.
If the next heap page contains `RData` objects, the `mrb_gc_unregistor()` function may be called from the `mrb_data_type::dfree` function.
At this time, the `mrb_gc_unregistor()` function gets an array object from a Ruby global variable.
If the array object belongs to a freed heap page, use-after-free is established by referencing this array object.
About the fixes.
First of all, there is the fact that the `mrb_gv_get()` function returns `nil` if `mrb->globals` is `NULL`.
Therefore, before destroying all objects, free `mrb->globals` and set `mrb->globals` to `NULL` at the same time.
Now the `mrb_gv_get()` function will return `nil` to the calling `mrb_gc_unregistor()` function and `mrb_gc_unregistor()` will do nothing more.
ref. https://github.com/mruby/mruby/issues/4618
As #6359 pointed out, calling const_missing hook from E_XXX_ERROR (that
calls mrb_exc_get_id()) can be an attack vector. Since E_XXX_ERROR is
supposed to be a defined error class, we think that the situation where
it is undefined and the const_missing hook is called should be detected
as an error; fix#6359
By adding a fast-path where we ignore boxed types we can gain a pretty substantial speedup of mrb_iv_get, making it about 25% faster during a standard optcarrot benchmark run.
NOTE: It is just mrb_iv_get that is that much faster, the whole benchmark seems to be about 3-5% faster with word boxing.
This will be a partial merge of #5317 with the following changes.
- Remove `iclass->iv_c` since `iclass->iv_c` is equivalent to `iclass->c`.
- `class_iv_ptr()` returns a single pointer instead of a double pointer.
Yukihiro "Matz" Matsumoto