* YJIT: implement getconstant YARV instruction
* Constant id is not a pointer
* Stack operands must be read after jit_prepare_routine_call
Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
The new version has an option to merge everything into a big
`extern "C"` block and it's nicer.
More importantly, this upgrade fixes an issue where Ubuntu with Clang 12
and macOS with Clang 14 gave a one line diff for `rb_shape_t`. It was
slightly annoying because we use macOS locally.
With this change, we're storing the iv name on an inline cache on
setinstancevariable instructions. This allows us to check the inline
cache to count instance variables set in initialize and give us an
estimate of iv capacity for an object.
For the purpose of estimating the number of instance variables required
for an object, we're assuming that all initialize methods will call
`super`.
This change allows us to estimate the number of instance variables
required without disassembling instruction sequences.
Co-Authored-By: Aaron Patterson <tenderlove@ruby-lang.org>
Prior to this commit the `OPTIMIZED_CMP` macro relied on a method lookup
to determine whether `<=>` was overridden. The result of the lookup was
cached, but only for the duration of the specific method that
initialized the cmp_opt_data cache structure.
With this method lookup, `[x,y].max` is slower than doing `x > y ?
x : y` even though there's an optimized instruction for "new array max".
(John noticed somebody a proposed micro-optimization based on this fact
in https://github.com/mastodon/mastodon/pull/19903.)
```rb
a, b = 1, 2
Benchmark.ips do |bm|
bm.report('conditional') { a > b ? a : b }
bm.report('method') { [a, b].max }
bm.compare!
end
```
Before:
```
Comparison:
conditional: 22603733.2 i/s
method: 19820412.7 i/s - 1.14x (± 0.00) slower
```
This commit replaces the method lookup with a new CMP basic op, which
gives the examples above equivalent performance.
After:
```
Comparison:
method: 24022466.5 i/s
conditional: 23851094.2 i/s - same-ish: difference falls within
error
```
Relevant benchmarks show an improvement to Array#max and Array#min when
not using the optimized newarray_max instruction as well. They are
noticeably faster for small arrays with the relevant types, and the same
or maybe a touch faster on larger arrays.
```
$ make benchmark COMPARE_RUBY=<master@5958c305> ITEM=array_min
$ make benchmark COMPARE_RUBY=<master@5958c305> ITEM=array_max
```
The benchmarks added in this commit also look generally improved.
Co-authored-by: John Hawthorn <jhawthorn@github.com>
This commit moves ruby_basic_operators and the unredefined macros out of
vm_core.h and into basic_operators.h so that we can use them more
broadly in places where we currently use a method look up via
`rb_method_basic_definition_p` (e.g. object.c, numeric.c, complex.c,
enum.c, but also in internal/compar.h after introducing BOP_CMP and
elsewhere if we introduce more BOPs)
The most controversial part of this change is probably moving
redefined_flag out of rb_vm_t. [vm_opt_method_def_table and
vm_opt_mid_table](9da2a5204f/vm.c)
are not part of rb_vm_t either, and I think this fits well with those.
But more significantly it seems to result in one fewer instruction. For
example:
Before:
```
(lldb) disassemble -n vm_opt_str_freeze
miniruby`vm_exec_core:
miniruby[0x10028233e] <+14558>: movq 0x11a86b(%rip), %rax ; ruby_current_vm_ptr
miniruby[0x100282345] <+14565>: testb $0x4, 0x242c(%rax)
```
After:
```
(lldb) disassemble -n vm_opt_str_freeze
ruby`vm_exec_core:
ruby[0x100280ebe] <+14510>: testb $0x4, 0x120147(%rip) ; ruby_vm_redefined_flag + 43
```
Co-authored-by: John Hawthorn <jhawthorn@github.com>
Certain code page sizes don't work and can cause crashes, so having this
value available as a command-line option is a bit dangerous. Remove it
and turn it into a constant instead.
* YJIT: Make case-when optimization respect === redefinition
Even when a fixnum key is in the dispatch hash, if there is a case such
that its basic operations for === is redefined, we need to fall back to
checking each case like the interpreter. Semantically we're always
checking each case by calling === in order, it's just that this is not
observable when basic operations are intact.
When all the keys are fixnums, though, we can do the optimization we're
doing right now. Check for this condition.
* Update yjit/src/cruby_bindings.inc.rs
Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
* YJIT: Reorder branches for Fixnum opt_case_dispatch
Co-authored-by: Maxime Chevalier-Boisvert <maxime.chevalierboisvert@shopify.com>
Co-authored-by: Alan Wu <alansi.xingwu@shopify.com>
* YJIT: Don't support too large values
Co-authored-by: Maxime Chevalier-Boisvert <maxime.chevalierboisvert@shopify.com>
Co-authored-by: Alan Wu <alansi.xingwu@shopify.com>
* Fix 32 and 16 bit register store in YJIT
Co-Authored-By: Takashi Kokubun <takashikkbn@gmail.com>
* Remove an unnecessary diff
* Reuse an rm_num_bits result
* Use u16::MAX instead
* Update the link
Co-authored-by: Alan Wu <XrXr@users.noreply.github.com>
* Just use sturh for 16 bits
Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
Co-authored-by: Alan Wu <XrXr@users.noreply.github.com>
Previously we essentially never freed block even after invalidation.
Their reference count never reached zero for a couple of reasons:
1. `Branch::block` formed a cycle with the block holding the branch
2. Strong count on a branch that has ever contained a stub never
reached 0 because we increment the `.clone()` call for
`BranchRef::into_raw()` didn't have a matching decrement.
It's not safe to immediately deallocate blocks during
invalidation since `branch_stub_hit()` can end up
running with a branch pointer from an invalidated branch.
To plug the leaks, we wait until code GC or global invalidation and
deallocate the blocks for iseqs that are definitely not running.
When we run global invalidation for TracePoints or code GC, we clear out
all blocks in our assumptions table but we don't deallocate the backing
buffers. Let's reclaim some memory during these rare events.
HashSet::clear() doesn't deallocate the backing buffer and shrink the
capacity. Replace with a 0-capcity set instead so we reclaim some memory
each code GC.
instead of FILE*.
Using C.fprintf is slower than String manipulation on memory. I'm going
to change the way MJIT writes files, and this is a prerequisite for it.
We frequently make branches that only have one target but we used to
always allocate space for two branch targets. This patch moves all the
information a branch target has into a struct and refer to them using
Option<Box<BranchTarget>>, this way when the second branch target is not
present it only takes 8 bytes.
Retained heap size on railsbench went from 16.17 MiB to 14.57 MiB, a
ratio of about 1.1.
YJIT: x86_64: Fix cmp with number where sign bit is set
Before this commit, we were unconditionally treating unsigned ints as
signed ints when counting the number of bits required for representing
the immediate in machine code. When the size of the immediate matches
the size of the other operand, no sign extension happens, so this was
incorrect. `asm.cmp(opnd64, 0x8000_0000)` panicked even though it's
encodable as `CMP r/m32, imm32`. Large shape ids were impacted by this
issue.
Co-Authored-By: Aaron Patterson <tenderlove@ruby-lang.org>
Co-Authored-By: Alan Wu <alanwu@ruby-lang.org>
Co-authored-by: Aaron Patterson <tenderlove@ruby-lang.org>
Co-authored-by: Alan Wu <alanwu@ruby-lang.org>
YJIT: Skip padding jumps to side exits
Co-authored-by: Maxime Chevalier-Boisvert <maxime.chevalierboisvert@shopify.com>
Co-authored-by: Alan Wu <alansi.xingwu@shopify.com>
Co-authored-by: Maxime Chevalier-Boisvert <maxime.chevalierboisvert@shopify.com>
Co-authored-by: Alan Wu <alansi.xingwu@shopify.com>
@casperisfine reporting a bug in this gist https://gist.github.com/casperisfine/d59e297fba38eb3905a3d7152b9e9350
After investigating I found it was caused by a combination of send and a c_func that we have overwritten in the JIT. For send calls, we need to do some stack manipulation before making the call. Because of the way exits works, we need to do that stack manipulation at the last possible moment. In this case, we weren't doing that stack manipulation at all. Unfortunately, with how the code is structured there isn't a great place to do that stack manipulation for our overridden C funcs.
Each overridden C func can return a boolean stating that it shouldn't be used. We would need to do the stack manipulation after all of those checks are done. We could pass a lambda(?) or separate out the logic for "can I run this override" from "now generate the code for it". Since we are coming up on a release, I went with the path of least resistence and just decided to not use these overrides if we are in a send call.
We definitely should revist this in the future.
* YJIT: Always encode Opnd::Value in 64 bits on x86_64
for GC offsets
Co-authored-by: Alan Wu <alansi.xingwu@shopify.com>
* Introduce heap_object_p
* Leave original mov intact
* Remove unneeded branches
* Add a test for movabs
Co-authored-by: Alan Wu <alansi.xingwu@shopify.com>
Takashi Kokubun
Maxime Chevalier-Boisvert
Alan Wu
Samuel Williams
Jemma Issroff
Daniel Colson
Maxime Chevalier-Boisvert
Aaron Patterson
Jimmy Miller