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]
On Android, a signal handler that is not SIG_DFL is set by default for
SIGSEGV. Ruby's install_sighandler inserts Ruby's handler only when the
signal has no handler, so it does not insert Ruby's SEGV report handler,
which caused some test failures.
This changeset forces to install Ruby's handler for some fatal signals
(sigbus, sigsegv, and sigill). They keep the original handlers, and
call them when the interpreter receives the signals.
Just refactoring.
The name "rb_bug_context" is completely unclear for me.
(Can you see that "context" means "machine register context"?)
The context is available only when a fatal signal (sigbus, sigsegv, or
sigill) is received; in fact, the function is used only for fatal
signals. So, I think the name should be changed.
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.
This reverts commits: 10d6a3aca78ba48c1b85fba8627dc1dd883de5ba6c6a25feca167e6b48f17cb96d41a53207979278595b3c4fdd1521f7cf89c11c5e69accf336082033632a812c0f56506be0d86427a3219 .
The reason for the revert is that we observe ABA problem around
inline method cache. When a cache misshits, we search for a
method entry. And if the entry is identical to what was cached
before, we reuse the cache. But the commits we are reverting here
introduced situations where a method entry is freed, then the
identical memory region is used for another method entry. An
inline method cache cannot detect that ABA.
Here is a code that reproduce such situation:
```ruby
require 'prime'
class << Integer
alias org_sqrt sqrt
def sqrt(n)
raise
end
GC.stress = true
Prime.each(7*37){} rescue nil # <- Here we populate CC
class << Object.new; end
# These adjacent remove-then-alias maneuver
# frees a method entry, then immediately
# reuses it for another.
remove_method :sqrt
alias sqrt org_sqrt
end
Prime.each(7*37).to_a # <- SEGV
```
Most (if not all) of the fields of rb_method_definition_t are never
meant to be modified once after they are stored. Marking them const
makes it possible for compilers to warn on unintended modifications.
This approach uses a flag bit on the final hash object in the regular splat,
as opposed to a previous approach that used a VM frame flag. The hash flag
approach is less invasive, and handles some cases that the VM frame flag
approach does not, such as saving the argument splat array and splatting it
later:
ruby2_keywords def foo(*args)
@args = args
bar
end
def bar
baz(*@args)
end
def baz(*args, **kw)
[args, kw]
end
foo(a:1) #=> [[], {a: 1}]
foo({a: 1}, **{}) #=> [[{a: 1}], {}]
foo({a: 1}) #=> 2.7: [[], {a: 1}] # and warning
foo({a: 1}) #=> 3.0: [[{a: 1}], {}]
It doesn't handle some cases that the VM frame flag handles, such as when
the final hash object is replaced using Hash#merge, but those cases are
probably less common and are unlikely to properly support keyword
argument separation.
Use ruby2_keywords to handle argument delegation in the delegate library.
The built-in version operates on a buffer of 5 words, much smaller than
the size of jmp_buf defined in libc.
Note, powerpc requires 5 words, while arm and x86_64 just require 3.
Also add keyword argument separation warnings for Class#new and Method#call.
To allow for keyword argument to required positional hash converstion in
cfuncs, add a vm frame flag indicating the cfunc was called with an empty
keyword hash (which was removed before calling the cfunc). The cfunc can
check this frame flag and add back an empty hash if it is passing its
arguments to another Ruby method. Add rb_empty_keyword_given_p function
for checking if called with an empty keyword hash, and
rb_add_empty_keyword for adding back an empty hash to argv.
All of this empty keyword argument support is only for 2.7. It will be
removed in 3.0 as Ruby 3 will not convert empty keyword arguments to
required positional hash arguments. Comment all of the relevent code
to make it obvious this is expected to be removed.
Add rb_funcallv_kw as an public C-API function, just like rb_funcallv
but with a keyword flag. This is used by rb_obj_call_init (internals
of Class#new). This also required expected call_type enum with
CALL_FCALL_KW, similar to the recent addition of CALL_PUBLIC_KW.
Add rb_vm_call_kw as a internal function, used by call_method_data
(internals of Method#call and UnboundMethod#bind_call). Add tests
for UnboundMethod#bind_call keyword handling.
The kw_splat flag is whether the original call passes keyword or not.
Some types of methods (e.g., bmethod and sym_proc) drops the
information. This change tries to propagate the flag to the final
callee, as far as I can.
This syntax means the method should be treated as a method that
uses keyword arguments, but no specific keyword arguments are
supported, and therefore calling the method with keyword arguments
will raise an ArgumentError. It is still allowed to double splat
an empty hash when calling the method, as that does not pass
any keyword arguments.
After 5e86b005c0, I now think ANYARGS is
dangerous and should be extinct. This commit deletes ANYARGS from
rb_thread_create, which seems very safe to do.
After 5e86b005c0, I now think ANYARGS is
dangerous and should be extinct. This commit deletes ANYARGS from
rb_ensure, which also revealed many arity / type mismatches.
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.
If `vm_stack` is left dangling in a forked process, the gc attempts to scan
it, but it is invalid and will cause a segfault. Therefore, we clear it
before forking.
In order to simplify this, `rb_ec_clear_vm_stack` was introduced.
Before this commit, classes and modules would be registered with the
VM's `defined_module_hash`. The key was the ID of the class, but that
meant that it was possible for hash collisions to occur. The compactor
doesn't allow classes in the `defined_module_hash` to move, but if there
is a conflict, then it's possible a class would be removed from the hash
and not get pined.
This commit changes the key / value of the hash just to be the class
itself, thus preventing movement.
For some reason symbols (or classes) are being overridden in trunk
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67598 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
This commit adds the new method `GC.compact` and compacting GC support.
Please see this issue for caveats:
https://bugs.ruby-lang.org/issues/15626
[Feature #15626]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67576 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Because hard to specify commits related to r67479 only.
So please commit again.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67499 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
This commit adds the new method `GC.compact` and compacting GC support.
Please see this issue for caveats:
https://bugs.ruby-lang.org/issues/15626
[Feature #15626]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67479 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
cfp->bp was (re-)introduced by Kokubun san, but VM doesn't use it
because I (ko1) want to remove it in a future. But using it make
leave instruction fast because of sp consisntency check.
So now VM uses cfp->bp.
To use cfp->bp, I checked the value and I found that it is not a
"initial value of sp" but a "initial value of ep". Fix this problem
and fix all bp references (this is why bp is renamed to bp_).
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67342 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
zlib and bignum both contain unblocking functions which are
async-signal-safe and do not require spawning additional
threads.
We can execute those functions directly in signal handlers
without incurring overhead of extra threads, so provide C-API
users the ability to deal with that. Other C-API users may
have similar need.
This flexible API can supercede existing uses of
rb_thread_call_without_gvl and rb_thread_call_without_gvl2 by
introducing a flags argument to control behavior.
Note: this API is NOT finalized. It needs approval from other
committers. I prefer shorter name than previous
rb_thread_call_without_gvl* functions because my eyes requires
big fonts.
[Bug #15499]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66712 b2dd03c8-39d4-4d8f-98ff-823fe69b080e