This PR improves the performance of `super` calls. While working on some
Rails optimizations jhawthorn discovered that `super` calls were slower
than expected.
The changes here do the following:
1) Adds a check for whether the call frame is not equal to the method
entry iseq. This avoids the `rb_obj_is_kind_of` check on the next line
which is quite slow. If the current call frame is equal to the method
entry we know we can't have an instance eval, etc.
2) Changes `FL_TEST` to `FL_TEST_RAW`. This is safe because we've
already done the check for `T_ICLASS` above.
3) Adds a benchmark for `T_ICLASS` super calls.
4) Note: makes a chage for `method_entry_cref` to use `const`.
On master the benchmarks showed that `super` is 1.76x slower. Our
changes improved the performance so that it is now only 1.36x slower.
Benchmark IPS:
```
Warming up --------------------------------------
super 244.918k i/100ms
method call 383.007k i/100ms
Calculating -------------------------------------
super 2.280M (± 6.7%) i/s - 11.511M in 5.071758s
method call 3.834M (± 4.9%) i/s - 19.150M in 5.008444s
Comparison:
method call: 3833648.3 i/s
super: 2279837.9 i/s - 1.68x (± 0.00) slower
```
With changes:
```
Warming up --------------------------------------
super 308.777k i/100ms
method call 375.051k i/100ms
Calculating -------------------------------------
super 2.951M (± 5.4%) i/s - 14.821M in 5.039592s
method call 3.551M (± 4.9%) i/s - 18.002M in 5.081695s
Comparison:
method call: 3551372.7 i/s
super: 2950557.9 i/s - 1.20x (± 0.00) slower
```
Ruby VM benchmarks also showed an improvement:
Existing `vm_super` benchmark`.
```
$ make benchmark ITEM=vm_super
| |compare-ruby|built-ruby|
|:---------|-----------:|---------:|
|vm_super | 21.555M| 37.819M|
| | -| 1.75x|
```
New `vm_iclass_super` benchmark:
```
$ make benchmark ITEM=vm_iclass_super
| |compare-ruby|built-ruby|
|:----------------|-----------:|---------:|
|vm_iclass_super | 1.669M| 3.683M|
| | -| 2.21x|
```
This is the benchmark script used for the benchmark-ips benchmarks:
```ruby
require "benchmark/ips"
class Foo
def zuper; end
def top; end
last_method = "top"
("A".."M").each do |module_name|
eval <<-EOM
module #{module_name}
def zuper; super; end
def #{module_name.downcase}
#{last_method}
end
end
prepend #{module_name}
EOM
last_method = module_name.downcase
end
end
foo = Foo.new
Benchmark.ips do |x|
x.report "super" do
foo.zuper
end
x.report "method call" do
foo.m
end
x.compare!
end
```
Co-authored-by: Aaron Patterson <tenderlove@ruby-lang.org>
Co-authored-by: John Hawthorn <john@hawthorn.email>
* Rewrite Kernel#tap with Ruby
This was good for VM too, but of course my intention is to unblock JIT's inlining of a block over yield
(inlining invokeyield has not been committed though).
* Fix test_settracefunc
About the :tap deletions, the :tap events are actually traced (we already have a TracePoint test for builtin methods),
but it's filtered out by tp.path == "xyzzy" (it became "<internal:kernel>"). We could trace tp.path == "<internal:kernel>"
cases too, but the lineno is impacted by kernel.rb changes and I didn't want to make it fragile for kernel.rb lineno changes.
for opt_* insns.
opt_eq handles rb_obj_equal inside opt_eq, and all other cfunc is
handled by opt_send_without_block. Therefore we can't decide which insn
should be generated by checking whether it's cfunc cc or not.
```
$ benchmark-driver -v --rbenv 'before --jit;after --jit' benchmark/mjit_opt_cc_insns.yml --repeat-count=4
before --jit: ruby 2.8.0dev (2020-06-26T05:21:43Z master 9dbc2294a6) +JIT [x86_64-linux]
after --jit: ruby 2.8.0dev (2020-06-26T06:30:18Z master 75cece1b0b) +JIT [x86_64-linux]
last_commit=Decide JIT-ed insn based on cached cfunc
Calculating -------------------------------------
before --jit after --jit
mjit_nil?(1) 73.878M 74.021M i/s - 40.000M times in 0.541432s 0.540391s
mjit_not(1) 72.635M 74.601M i/s - 40.000M times in 0.550702s 0.536187s
mjit_eq(1, nil) 7.331M 7.445M i/s - 8.000M times in 1.091211s 1.074596s
mjit_eq(nil, 1) 49.450M 64.711M i/s - 8.000M times in 0.161781s 0.123627s
Comparison:
mjit_nil?(1)
after --jit: 74020528.4 i/s
before --jit: 73878185.9 i/s - 1.00x slower
mjit_not(1)
after --jit: 74600882.0 i/s
before --jit: 72634507.6 i/s - 1.03x slower
mjit_eq(1, nil)
after --jit: 7444657.4 i/s
before --jit: 7331304.3 i/s - 1.02x slower
mjit_eq(nil, 1)
after --jit: 64710790.6 i/s
before --jit: 49449507.4 i/s - 1.31x slower
```
because opt_nil/opt_not/opt_eq populates cc even when it doesn't
fallback to opt_send_without_block because of vm_method_cfunc_is.
```
$ benchmark-driver -v --rbenv 'before --jit;after --jit' benchmark/mjit_opt_cc_insns.yml --repeat-count=4
before --jit: ruby 2.8.0dev (2020-06-22T08:11:24Z master d231b8f95b) +JIT [x86_64-linux]
after --jit: ruby 2.8.0dev (2020-06-22T08:53:27Z master e1125879ed) +JIT [x86_64-linux]
last_commit=Compile opt_send for opt_* only when cc has ISeq
Calculating -------------------------------------
before --jit after --jit
mjit_nil?(1) 54.106M 73.693M i/s - 40.000M times in 0.739288s 0.542795s
mjit_not(1) 53.398M 74.477M i/s - 40.000M times in 0.749090s 0.537075s
mjit_eq(1, nil) 7.427M 6.497M i/s - 8.000M times in 1.077136s 1.231326s
Comparison:
mjit_nil?(1)
after --jit: 73692594.3 i/s
before --jit: 54106108.4 i/s - 1.36x slower
mjit_not(1)
after --jit: 74477487.9 i/s
before --jit: 53398125.0 i/s - 1.39x slower
mjit_eq(1, nil)
before --jit: 7427105.9 i/s
after --jit: 6497063.0 i/s - 1.14x slower
```
Actually opt_eq becomes slower by this. Maybe it's indeed using
opt_send_without_block, but I'll approach that one in another commit.
These days I don't use `make benchmark`. The YAML files should be
executable with bare `benchmark-driver` CLI without passing
`RUBYOPT=-Ibenchmark/lib`.
A prerequisite to fix https://bugs.ruby-lang.org/issues/15589 with JIT.
This commit alone doesn't make a significant difference yet, but I thought
this commit should be committed independently.
This method override was discussed in [Misc #16961].
The vm1_ prefix and vm2_ had had special meaning until
820ad9cb1d and
12068aa4e9. AFAIK there's no special
meaning in vm3_ prefix.
As they have confused people (like "In `benchmark` what is difference
between `vm1_`, `vm2_` and `vm3_`"), I'd like to remove the obsoleted
prefix as we obviated that two years ago.
for VM_METHOD_TYPE_CFUNC.
This has been known to decrease optcarrot fps:
```
$ benchmark-driver -v --rbenv 'before --jit;after --jit' benchmark.yml --repeat-count=24 --output=all
before --jit: ruby 2.8.0dev (2020-04-13T16:25:13Z master fb40495cd9) +JIT [x86_64-linux]
after --jit: ruby 2.8.0dev (2020-04-13T23:23:11Z mjit-inline-c bdcd06d159) +JIT [x86_64-linux]
Calculating -------------------------------------
before --jit after --jit
Optcarrot Lan_Master.nes 66.38132676191719 67.41369177299630 fps
69.42728743772243 68.90327567263054
72.16028300263211 69.62605130880686
72.46631319102777 70.48818243767207
73.37078877002490 70.79522887347566
73.69422431217367 70.99021920193194
74.01471487018695 74.69931965402584
75.48685183295630 74.86714575949016
75.54445264507932 75.97864419721677
77.28089738169756 76.48908637569581
78.04183397891302 76.54320932488021
78.36807984096562 76.59407262898067
78.92898762543574 77.31316743361343
78.93576483233765 77.97153484180480
79.13754917503078 77.98478782102325
79.62648945850653 78.02263322726446
79.86334213878064 78.26333724045934
80.05100635898518 78.60056756355614
80.26186843769584 78.91082645644468
80.34205717020330 79.01226659142263
80.62286066044338 79.32733939423721
80.95883033058557 79.63793060542024
80.97376819251613 79.73108936622778
81.23050939202896 80.18280109433088
```
and I deleted this capability in an early stage of YARV-MJIT development:
0ab130feee
I suspect either of the following things could be the cause:
* Directly calling vm_call_cfunc requires more optimization effort in GCC,
resulting in 30ms-ish compilation time increase for such methods and
decreasing the number of methods compiled in a benchmarked period.
* Code size increase => icache miss hit
These hypotheses could be verified by some methodologies. However, I'd
like to introduce this regardless of the result because this blocks
inlining C method's definition.
I may revert this commit when I give up to implement inlining C method
definition, which requires this change.
Microbenchmark-wise, this gives slight performance improvement:
```
$ benchmark-driver -v --rbenv 'before --jit;after --jit' benchmark/mjit_send_cfunc.yml --repeat-count=4
before --jit: ruby 2.8.0dev (2020-04-13T16:25:13Z master fb40495cd9) +JIT [x86_64-linux]
after --jit: ruby 2.8.0dev (2020-04-13T23:23:11Z mjit-inline-c bdcd06d159) +JIT [x86_64-linux]
Calculating -------------------------------------
before --jit after --jit
mjit_send_cfunc 41.961M 56.489M i/s - 100.000M times in 2.383143s 1.770244s
Comparison:
mjit_send_cfunc
after --jit: 56489372.5 i/s
before --jit: 41961388.1 i/s - 1.35x slower
```
Previously, passing a keyword splat to a method always allocated
a hash on the caller side, and accepting arbitrary keywords in
a method allocated a separate hash on the callee side. Passing
explicit keywords to a method that accepted a keyword splat
did not allocate a hash on the caller side, but resulted in two
hashes allocated on the callee side.
This commit makes passing a single keyword splat to a method not
allocate a hash on the caller side. Passing multiple keyword
splats or a mix of explicit keywords and a keyword splat still
generates a hash on the caller side. On the callee side,
if arbitrary keywords are not accepted, it does not allocate a
hash. If arbitrary keywords are accepted, it will allocate a
hash, but this commit uses a callinfo flag to indicate whether
the caller already allocated a hash, and if so, the callee can
use the passed hash without duplicating it. So this commit
should make it so that a maximum of a single hash is allocated
during method calls.
To set the callinfo flag appropriately, method call argument
compilation checks if only a single keyword splat is given.
If only one keyword splat is given, the VM_CALL_KW_SPLAT_MUT
callinfo flag is not set, since in that case the keyword
splat is passed directly and not mutable. If more than one
splat is used, a new hash needs to be generated on the caller
side, and in that case the callinfo flag is set, indicating
the keyword splat is mutable by the callee.
In compile_hash, used for both hash and keyword argument
compilation, if compiling keyword arguments and only a
single keyword splat is used, pass the argument directly.
On the caller side, in vm_args.c, the callinfo flag needs to
be recognized and handled. Because the keyword splat
argument may not be a hash, it needs to be converted to a
hash first if not. Then, unless the callinfo flag is set,
the hash needs to be duplicated. The temporary copy of the
callinfo flag, kw_flag, is updated if a hash was duplicated,
to prevent the need to duplicate it again. If we are
converting to a hash or duplicating a hash, we need to update
the argument array, which can including duplicating the
positional splat array if one was passed. CALLER_SETUP_ARG
and a couple other places needs to be modified to handle
similar issues for other types of calls.
This includes fairly comprehensive tests for different ways
keywords are handled internally, checking that you get equal
results but that keyword splats on the caller side result in
distinct objects for keyword rest parameters.
Included are benchmarks for keyword argument calls.
Brief results when compiled without optimization:
def kw(a: 1) a end
def kws(**kw) kw end
h = {a: 1}
kw(a: 1) # about same
kw(**h) # 2.37x faster
kws(a: 1) # 1.30x faster
kws(**h) # 2.19x faster
kw(a: 1, **h) # 1.03x slower
kw(**h, **h) # about same
kws(a: 1, **h) # 1.16x faster
kws(**h, **h) # 1.14x faster
Instead of searching twice to extract and to delete, extract and
delete the found position at the first search.
This makes faster nearly twice, for regexps and strings.
| |compare-ruby|built-ruby|
|:-------------|-----------:|---------:|
|regexp-short | 2.143M| 3.918M|
|regexp-long | 105.162k| 205.410k|
|string-short | 3.789M| 7.964M|
|string-long | 1.301M| 2.457M|
I noticed that some files in rubygems were executable, and I could think
of no reason why they should be.
In general, I think ruby files should never have the executable bit set
unless they include a shebang, so I run the following command over the
whole repo:
```bash
find . -name '*.rb' -type f -executable -exec bash -c 'grep -L "^#!" $1 || chmod -x $1' _ {} \;
```
* Stop making a redundant hash copy in Hash#dup
It was making a copy of the hash without rehashing, then created an
extra copy of the hash to do the rehashing. Since rehashing creates
a new copy already, this change just uses that rehashing to make
the copy.
[Bug #16121]
* Remove redundant Check_Type after to_hash
* Fix freeing and clearing destination hash in Hash#initialize_copy
The code was assuming the state of the destination hash based on the
source hash for clearing any existing table on it. If these don't match,
then that can cause the old table to be leaked. This can be seen by
compiling hash.c with `#define HASH_DEBUG 1` and running the following
script, which will crash from a debug assertion.
```ruby
h = 9.times.map { |i| [i, i] }.to_h
h.send(:initialize_copy, {})
```
* Remove dead code paths in rb_hash_initialize_copy
Given that `RHASH_ST_TABLE_P(h)` is defined as `(!RHASH_AR_TABLE_P(h))`
it shouldn't be possible for a hash to be neither of these, so there
is no need for the removed `else if` blocks.
* Share implementation between Hash#replace and Hash#initialize_copy
This also fixes key rehashing for small hashes backed by an array
table for Hash#replace. This used to be done consistently in ruby
2.5.x, but stopped being done for small arrays in ruby 2.6.x.
This also bring optimization improvements that were done for
Hash#initialize_copy to Hash#replace.
* Add the Hash#dup benchmark
I noticed that in case of cache misshit, re-calculated cc->me can
be the same method entry than the pevious one. That is an okay
situation but can't we partially reuse the cache, because cc->call
should still be valid then?
One thing that has to be special-cased is when the method entry
gets amended by some refinements. That happens behind-the-scene
of call cache mechanism. We have to check if cc->me->def points to
the previously saved one.
Calculating -------------------------------------
trunk ours
vm2_poly_same_method 1.534M 2.025M i/s - 6.000M times in 3.910203s 2.962752s
Comparison:
vm2_poly_same_method
ours: 2025143.9 i/s
trunk: 1534447.2 i/s - 1.32x slower
eileencodes
Jean Boussier
Nobuyoshi Nakada
Kenta Murata
Takashi Kokubun
Vladimir Dementyev
Ryuta Kamizono
卜部昌平
S.H
Jeremy Evans
Kazuhiro NISHIYAMA
Lourens Naudé
David Rodríguez
Dylan Thacker-Smith
Masato Ohba
Yaw Boakye
Yusuke Endoh