I'm planning to introduce mjit_compiler.rb, and I want to make this
consistent with it. Consistency with compile.c doesn't seem important
for MJIT anyway.
This commit implements Objects on Variable Width Allocation. This allows
Objects with more ivars to be embedded (i.e. contents directly follow the
object header) which improves performance through better cache locality.
This commit reintroduces finer-grained constant cache invalidation.
After 8008fb7 got merged, it was causing issues on token-threaded
builds (such as on Windows).
The issue was that when you're iterating through instruction sequences
and using the translator functions to get back the instruction structs,
you're either using `rb_vm_insn_null_translator` or
`rb_vm_insn_addr2insn2` depending if it's a direct-threading build.
`rb_vm_insn_addr2insn2` does some normalization to always return to
you the non-trace version of whatever instruction you're looking at.
`rb_vm_insn_null_translator` does not do that normalization.
This means that when you're looping through the instructions if you're
trying to do an opcode comparison, it can change depending on the type
of threading that you're using. This can be very confusing. So, this
commit creates a new translator function
`rb_vm_insn_normalizing_translator` to always return the non-trace
version so that opcode comparisons don't have to worry about different
configurations.
[Feature #18589]
This reverts commits for [Feature #18589]:
* 8008fb7352
"Update formatting per feedback"
* 8f6eaca2e1
"Delete ID from constant cache table if it becomes empty on ISEQ free"
* 629908586b
"Finer-grained inline constant cache invalidation"
MSWin builds on AppVeyor have been crashing since the merger.
Current behavior - caches depend on a global counter. All constant mutations cause caches to be invalidated.
```ruby
class A
B = 1
end
def foo
A::B # inline cache depends on global counter
end
foo # populate inline cache
foo # hit inline cache
C = 1 # global counter increments, all caches are invalidated
foo # misses inline cache due to `C = 1`
```
Proposed behavior - caches depend on name components. Only constant mutations with corresponding names will invalidate the cache.
```ruby
class A
B = 1
end
def foo
A::B # inline cache depends constants named "A" and "B"
end
foo # populate inline cache
foo # hit inline cache
C = 1 # caches that depend on the name "C" are invalidated
foo # hits inline cache because IC only depends on "A" and "B"
```
Examples of breaking the new cache:
```ruby
module C
# Breaks `foo` cache because "A" constant is set and the cache in foo depends
# on "A" and "B"
class A; end
end
B = 1
```
We expect the new cache scheme to be invalidated less often because names aren't frequently reused. With the cache being invalidated less, we can rely on its stability more to keep our constant references fast and reduce the need to throw away generated code in YJIT.
Use ISEQ_BODY macro to get the rb_iseq_constant_body of the ISeq. Using
this macro will make it easier for us to change the allocation strategy
of rb_iseq_constant_body when using Variable Width Allocation.
Lazily compile out a chain of checks for different known classes and
whether `self` embeds its ivars or not.
* Remove trailing whitespaces
* Get proper addresss in Capstone disassembly
* Lowercase address in Capstone disassembly
Capstone uses lowercase for jump targets in generated listings. Let's
match it.
* Use the same successor in getivar guard chains
Cuts down on duplication
* Address reviews
* Fix copypasta error
* Add a comment
This updates the trace instructions to directly dispatch to
opt_send_without_block. So this should cause no slowdown in
non-trace mode.
To enable the tracing of the optimized methods, RUBY_EVENT_C_CALL
and RUBY_EVENT_C_RETURN are added as events to the specialized
instructions.
Fixes [Bug #14870]
Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
I'm investigating SEGVs like 2715166621.
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.
on interruption.
The cancellation code was originally written for leave insn, but re-entering
opt_invokebuiltin_delegate_leave insn on a cancellation is not safe, because
a builtin function is executed twice.
e7fc353f04 reverted vm_ic_hit_p's signature change made in 53babf35ef,
which broke JIT compilation of getinlinecache.
To make sure it doesn't happen again, I separated vm_inlined_ic_hit_p to
make the intention clear.
constant cache `IC` is accessed by non-atomic manner and there are
thread-safety issues, so Ruby 3.0 disables to use const cache on
non-main ractors.
This patch enables it by introducing `imemo_constcache` and allocates
it by every re-fill of const cache like `imemo_callcache`.
[Bug #17510]
Now `IC` only has one entry `IC::entry` and it points to
`iseq_inline_constant_cache_entry`, managed by T_IMEMO object.
`IC` is atomic data structure so `rb_mjit_before_vm_ic_update()` and
`rb_mjit_after_vm_ic_update()` is not needed.
when we already check ROBJECT_NUMIV(self) is larger than
ROBJECT_EMBED_LEN_MAX at the beginning of the method, because the number
of instance variables for the same object doesn't decrease.
```
$ benchmark-driver -v --rbenv 'before --jit;after --jit' --repeat-count=4 --alternate --output=all benchmark_3000.yml
before --jit: ruby 3.0.0dev (2020-12-23T06:32:19Z master dbb4f19969) +JIT [x86_64-linux]
after --jit: ruby 3.0.0dev (2020-12-23T07:45:42Z master 95e866c098) +JIT [x86_64-linux]
last_commit=Skip checking ROBJECT_EMBED
Calculating -------------------------------------
before --jit after --jit
Optcarrot 3000 frames 102.34091772397872 102.77738408379015 fps
103.37784821624231 105.46530219076179
104.39567016876369 106.43712452152215
105.31782092252713 106.54986150067481
```