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
This patch contains several ideas:
(1) Disposable inline method cache (IMC) for race-free inline method cache
* Making call-cache (CC) as a RVALUE (GC target object) and allocate new
CC on cache miss.
* This technique allows race-free access from parallel processing
elements like RCU.
(2) Introduce per-Class method cache (pCMC)
* Instead of fixed-size global method cache (GMC), pCMC allows flexible
cache size.
* Caching CCs reduces CC allocation and allow sharing CC's fast-path
between same call-info (CI) call-sites.
(3) Invalidate an inline method cache by invalidating corresponding method
entries (MEs)
* Instead of using class serials, we set "invalidated" flag for method
entry itself to represent cache invalidation.
* Compare with using class serials, the impact of method modification
(add/overwrite/delete) is small.
* Updating class serials invalidate all method caches of the class and
sub-classes.
* Proposed approach only invalidate the method cache of only one ME.
See [Feature #16614] for more details.
Now, rb_call_info contains how to call the method with tuple of
(mid, orig_argc, flags, kwarg). Most of cases, kwarg == NULL and
mid+argc+flags only requires 64bits. So this patch packed
rb_call_info to VALUE (1 word) on such cases. If we can not
represent it in VALUE, then use imemo_callinfo which contains
conventional callinfo (rb_callinfo, renamed from rb_call_info).
iseq->body->ci_kw_size is removed because all of callinfo is VALUE
size (packed ci or a pointer to imemo_callinfo).
To access ci information, we need to use these functions:
vm_ci_mid(ci), _flag(ci), _argc(ci), _kwarg(ci).
struct rb_call_info_kw_arg is renamed to rb_callinfo_kwarg.
rb_funcallv_with_cc() and rb_method_basic_definition_p_with_cc()
is temporary removed because cd->ci should be marked.
Let me quote ISO/IEC 9899:2018 section 6.5.15:
> Constraints
>
> The first operand shall have scalar type.
> One of the following shall hold for the second and third operands:
> — both operands have arithmetic type;
> — both operands have the same structure or union type;
> — both operands have void type;
(snip)
Here, `*option` is a const struct rb_compile_option_struct. OTOH
`COMPILE_OPTION_DEFAULT` is a struct rb_compile_option_struct, without
const. These two are _not_ the "same structure or union type". Hence
the expression renders undefined behaviour. COMPILE_OPTION_DEFAULT is
not a const because `RubyVM::InstructionSequence.compile_option=`
touches its internals on-the-fly. There is no way to meet the
constraints quoted above.
Using ternary operator here was a mistake at the first place. Let's
just replace it with a normal `if` statement.
Saves comitters' daily life by avoid #include-ing everything from
internal.h to make each file do so instead. This would significantly
speed up incremental builds.
We take the following inclusion order in this changeset:
1. "ruby/config.h", where _GNU_SOURCE is defined (must be the very
first thing among everything).
2. RUBY_EXTCONF_H if any.
3. Standard C headers, sorted alphabetically.
4. Other system headers, maybe guarded by #ifdef
5. Everything else, sorted alphabetically.
Exceptions are those win32-related headers, which tend not be self-
containing (headers have inclusion order dependencies).
(This is the second try of 036bc1da6c6c9b0fa9b7f5968d897a9554dd770e.)
If iseq is GC'ed, the pointer of iseq may be reused, which may hide a
deprecation warning of keyword argument change.
http://ci.rvm.jp/results/trunk-test1@phosphorus-docker/2474221
```
1) Failure:
TestKeywordArguments#test_explicit_super_kwsplat [/tmp/ruby/v2/src/trunk-test1/test/ruby/test_keyword.rb:549]:
--- expected
+++ actual
@@ -1 +1 @@
-/The keyword argument is passed as the last hash parameter.* for `m'/m
+""
```
This change ad-hocly adds iseq_unique_id for each iseq, and use it
instead of iseq pointer. This covers the case where caller is GC'ed.
Still, the case where callee is GC'ed, is not covered.
But anyway, it is very rare that iseq is GC'ed. Even when it occurs, it
just hides some warnings. It's no big deal.
If iseq is GC'ed, the pointer of iseq may be reused, which may hide a
deprecation warning of keyword argument change.
http://ci.rvm.jp/results/trunk-test1@phosphorus-docker/2474221
```
1) Failure:
TestKeywordArguments#test_explicit_super_kwsplat [/tmp/ruby/v2/src/trunk-test1/test/ruby/test_keyword.rb:549]:
--- expected
+++ actual
@@ -1 +1 @@
-/The keyword argument is passed as the last hash parameter.* for `m'/m
+""
```
This change ad-hocly adds iseq_unique_id for each iseq, and use it
instead of iseq pointer. This covers the case where caller is GC'ed.
Still, the case where callee is GC'ed, is not covered.
But anyway, it is very rare that iseq is GC'ed. Even when it occurs, it
just hides some warnings. It's no big deal.
This commit introduces an "inline ivar cache" struct. The reason we
need this is so compaction can differentiate from an ivar cache and a
regular inline cache. Regular inline caches contain references to
`VALUE` and ivar caches just contain references to the ivar index. With
this new struct we can easily update references for inline caches (but
not inline var caches as they just contain an int)
These functions are used from within a compilation unit so we can
make them static, for better binary size. This changeset reduces
the size of generated ruby binary from 26,590,128 bytes to
26,584,472 bytes on my macihne.
We incorrectly assumed that the `file` argument should be the file name and
caused https://github.com/scoutapp/scout_apm_ruby/issues/307 because
exception backtrace did not contain correct path. This documentation
clarifies the role of the different arguments and provides extra
examples.
This removes the security features added by $SAFE = 1, and warns for access
or modification of $SAFE from Ruby-level, as well as warning when calling
all public C functions related to $SAFE.
This modifies some internal functions that took a safe level argument
to no longer take the argument.
rb_require_safe now warns, rb_require_string has been added as a
version that takes a VALUE and does not warn.
One public C function that still takes a safe level argument and that
this doesn't warn for is rb_eval_cmd. We may want to consider
adding an alternative method that does not take a safe level argument,
and warn for rb_eval_cmd.
Looking at the list of symbols inside of libruby-static.a, I found
hundreds of functions that are defined, but used from nowhere.
There can be reasons for each of them (e.g. some functions are
specific to some platform, some are useful when debugging, etc).
However it seems the functions deleted here exist for no reason.
This changeset reduces the size of ruby binary from 26,671,456
bytes to 26,592,864 bytes on my machine.
Fixes [Bug #16332]
Constant access was changed to no longer allow top-level constant access
through `nil`, but `defined?` wasn't changed at the same time to stay
consistent.
Use a separate defined type to distinguish between a constant
referenced from the current lexical scope and one referenced from
another namespace.
Support loading builtin features written in Ruby, which implement
with C builtin functions.
[Feature #16254]
Several features:
(1) Load .rb file at boottime with native binary.
Now, prelude.rb is loaded at boottime. However, this file is contained
into the interpreter as a text format and we need to compile it.
This patch contains a feature to load from binary format.
(2) __builtin_func() in Ruby call func() written in C.
In Ruby file, we can write `__builtin_func()` like method call.
However this is not a method call, but special syntax to call
a function `func()` written in C. C functions should be defined
in a file (same compile unit) which load this .rb file.
Functions (`func` in above example) should be defined with
(a) 1st parameter: rb_execution_context_t *ec
(b) rest parameters (0 to 15).
(c) VALUE return type.
This is very similar requirements for functions used by
rb_define_method(), however `rb_execution_context_t *ec`
is new requirement.
(3) automatic C code generation from .rb files.
tool/mk_builtin_loader.rb creates a C code to load .rb files
needed by miniruby and ruby command. This script is run by
BASERUBY, so *.rb should be written in BASERUBY compatbile
syntax. This script load a .rb file and find all of __builtin_
prefix method calls, and generate a part of C code to export
functions.
tool/mk_builtin_binary.rb creates a C code which contains
binary compiled Ruby files needed by ruby command.
We need to ensure that labels are pinned while disassembling. If the
compactor runs during disassembly, references to these labels could go
bad, so this commit just ensures that the labels can't move until we're
done.
To perform a regular method call, the VM needs two structs,
`rb_call_info` and `rb_call_cache`. At the moment, we allocate these two
structures in separate buffers. In the worst case, the CPU needs to read
4 cache lines to complete a method call. Putting the two structures
together reduces the maximum number of cache line reads to 2.
Combining the structures also saves 8 bytes per call site as the current
layout uses separate two pointers for the call info and the call cache.
This saves about 2 MiB on Discourse.
This change improves the Optcarrot benchmark at least 3%. For more
details, see attached bugs.ruby-lang.org ticket.
Complications:
- A new instruction attribute `comptime_sp_inc` is introduced to
calculate SP increase at compile time without using call caches. At
compile time, a `TS_CALLDATA` operand points to a call info struct, but
at runtime, the same operand points to a call data struct. Instruction
that explicitly define `sp_inc` also need to define `comptime_sp_inc`.
- MJIT code for copying call cache becomes slightly more complicated.
- This changes the bytecode format, which might break existing tools.
[Misc #16258]
This changeset basically replaces `ruby_xmalloc(x * y)` into
`ruby_xmalloc2(x, y)`. Some convenient functions are also
provided for instance `rb_xmalloc_mul_add(x, y, z)` which allocates
x * y + z byes.
ko1 cannot remember why he introduced the function. And it is not used.
After it is removed, the argument "base_block" of
rb_iseq_compile_with_option is always zero.
The parsing of `RubyVM::InstructionSequence.compile` does not support an
outer scope currently. So it specified NULL as parent_iseq for the
parser. However, it resulted in the following false-positive warning.
```
RubyVM::InstructionSequence.compile(<<END)
o = Object.new
o #=> <compiled>:2: warning: possibly useless use of a variable in void context
END
```
This change specifies a dummy empty parent_iseq instead of NULL, which
suppresses the false positive.
The parser needs to determine whether a local varaiable is defined or
not in outer scope. For the sake, "base_block" field has kept the outer
block.
However, the whole block was actually unneeded; the parser used only
base_block->iseq.
So, this change lets parser_params have the iseq directly, instead of
the whole block.
After 5e86b005c0, I now think ANYARGS is
dangerous and should be extinct. This commit deletes ANYARGS from
struct vm_ifunc, but in doing so we also have to decouple the usage
of this struct in compile.c, which (I think) is an abuse of ANYARGS.
Without doing this, enabling a TracePoint on a method could lead to use
of moved objects. This was found by running
`env RUBY_ISEQ_DUMP_DEBUG=to_binary make test-all`, which sets
orignal_iseq then runs the compaction tests and the tracepoint tests.
Please excuse the lack of tests. I was not able to figure out how to
reliably trigger a move on a specific iseq imemo to make a good
regression test.
To manually confirm the problem and this fix, you can run:
```
env RUBY_ISEQ_DUMP_DEBUG=to_binary make test-all \
TESTOPTS="test/ruby/test_gc_compact.rb \
test/gdbm/test_gdbm.rb \
test/ruby/test_settracefunc.rb"
```
Or the following script:
```ruby
tp = TracePoint.new(:line) {}
1.times do # put it in a block to not keep these objects alive
objects = 10_000.times.map { Object.new }
objects.hash
end
1.times do
# this allocation pattern can realistically happen in an app
# at load time
beek = 10_000.times.map do
eval(<<-RUBY)
def foo
a + b
1.times {
4 + 234234
}
nil + 234
end
RUBY
Object.new
Object.new
end
beek.hash
end
tp.enable(target: self.:foo) { 234 } # allocate original iseq
GC.verify_compaction_references(toward: :empty)
GC.compact
tp.enable(target: self.:foo) { 234234 } # crash
```
[Bug #16098]
* Make it clear as possible that RubyVM is MRI-specific and only exists on MRI
* See [Bug #15743].
* Use "CRuby VM" instead of "Ruby VM" for clarity.
* Use YARV rather than "CRuby VM" for documenting RubyVM::InstructionSequence
* Avoid introducing a new "CRuby VM" term in documentation
Renaming this function. "No pin" leaks some implementation details. We
just want users to know that if they mark this object, the reference may
move and they'll need to update the reference accordingly.
Jeremy Evans
Takashi Kokubun
Koichi Sasada
卜部昌平
0x005c
Nobuyoshi Nakada
Yusuke Endoh
Aaron Patterson
Samuel Williams
Dylan Thacker-Smith
Lourens Naudé
Alan Wu
Benoit Daloze
git