The order of iseq may differ from the order of tokens, typically
`while`/`until` conditions are put after the body.
These orders can match by using line numbers as builtin-indexes, but
at the same time, it introduces the restriction that multiple `cexpr!`
and `cstmt!` cannot appear in the same line.
Another possible idea is to use `RubyVM::AbstractSyntaxTree` and
`node_id` instead of ripper, with making BASERUBY 3.1 or later.
Previously on builds with optimizations disabled, this could result in
an out of bounds read. When we had all of:
* built with -O0
* Leaf builtin
* Primitive.mandatory_only
* "no args builtin", called by vm_call_single_noarg_inline_builti
* The stack is escaped to the heap via binding or a proc
This is because mk_builtin_loader generated reads for all locals
regardless of whether they were used and in the case we generated a
mandatory_only iseq that would include more variables than were actually
available.
On optimized builds, the invalid accesses would be optimized away, and
this also was often unnoticed as the invalid access would just hit
another part of the stack unless it had been escaped to the heap.
The fix here is imperfect, as this could have false positives, but since
Primitive.cexpr! is only available within the cruby codebase itself
that's probably fine as a proper fix would be much more challenging (the
only false positives we found were in rjit.rb).
Fixes [Bug #20178]
Co-authored-by: Adam Hess <HParker@github.com>
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.
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.
Compare with the C methods, A built-in methods written in Ruby is
slower if only mandatory parameters are given because it needs to
check the argumens and fill default values for optional and keyword
parameters (C methods can check the number of parameters with `argc`,
so there are no overhead). Passing mandatory arguments are common
(optional arguments are exceptional, in many cases) so it is important
to provide the fast path for such common cases.
`Primitive.mandatory_only?` is a special builtin function used with
`if` expression like that:
```ruby
def self.at(time, subsec = false, unit = :microsecond, in: nil)
if Primitive.mandatory_only?
Primitive.time_s_at1(time)
else
Primitive.time_s_at(time, subsec, unit, Primitive.arg!(:in))
end
end
```
and it makes two ISeq,
```
def self.at(time, subsec = false, unit = :microsecond, in: nil)
Primitive.time_s_at(time, subsec, unit, Primitive.arg!(:in))
end
def self.at(time)
Primitive.time_s_at1(time)
end
```
and (2) is pointed by (1). Note that `Primitive.mandatory_only?`
should be used only in a condition of an `if` statement and the
`if` statement should be equal to the methdo body (you can not
put any expression before and after the `if` statement).
A method entry with `mandatory_only?` (`Time.at` on the above case)
is marked as `iseq_overload`. When the method will be dispatch only
with mandatory arguments (`Time.at(0)` for example), make another
method entry with ISeq (2) as mandatory only method entry and it
will be cached in an inline method cache.
The idea is similar discussed in https://bugs.ruby-lang.org/issues/16254
but it only checks mandatory parameters or more, because many cases
only mandatory parameters are given. If we find other cases (optional
or keyword parameters are used frequently and it hurts performance),
we can extend the feature.
This commit fixes compiler error on MSVC. %p on that platform is not
suitable to represent a compile-time constant.
34017163/job/vj2a8uk3gwv9yxak (L24381)
Noticed that struct rb_builtin_function is a purely compile-time
constant. MJIT can eliminate some runtime calculations by statically
generate dedicated C code generator for each builtin functions.
Primitve.cexpr! and .cstmt! can access Ruby's parameter and
*local variables* (note that local parameters are also local
variables). However recent changes only allow to access
parameters. This patch fix it.
For example, the following code can work:
def foo a, b, k: :kw, **kwrest
c = a + b
d = k
e = kwrest
p Primitive.cstmt!(%q(rb_p(rb_ary_new_from_args(5, a, b, c, d, e));
return Qnil;))
end
with Ripper.
a3e6f52c17 introduced __builtin_cexpr! and
__builtin_cstmt!, but nobody has used them and then they broke on
79292b3088 by undefined `params`.
This patch fixes the undefined `params`, but still we're not using them
yet.
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).
Now, C functions written by __builtin_cexpr!(code) and others are
named as "__builtin_inline#{n}". However, it is difficult to know
what the function is. This patch rename them into
"__builtin_foo_#{lineno}" when cexpr! is in 'foo' method.
rename __builtin_inline!(code) to __builtin_cstmt(code).
Also this commit introduce the following inlining C code features.
* __builtin_cstmt!(STMT)
(renamed from __builtin_inline!)
Define a function which run STMT implicitly and call this function at
evatuation time. Note that you need to return some value in STMT.
If there is a local variables (includes method parameters), you can
read these values.
static VALUE func(ec, self) {
VALUE x = ...;
STMT
}
Usage:
def double a
# a is readable from C code.
__builtin_cstmt! 'return INT2FIX(FIX2INT(a) * 2);'
end
* __builtin_cexpr!(EXPR)
Define a function which invoke EXPR implicitly like `__builtin_cstmt!`.
Different from cstmt!, which compiled with `return EXPR;`.
(`return` and `;` are added implicitly)
static VALUE func(ec, self) {
VALUE x = ...;
return EXPPR;
}
Usage:
def double a
__builtin_cexpr! 'INT2FIX(FIX2INT(a) * 2)'
end
* __builtin_cconst!(EXPR)
Define a function which invoke EXPR implicitly like cexpr!.
However, the function is called once at compile time, not evaluated time.
Any local variables are not accessible (because there is no local variable
at compile time).
Usage:
GCC = __builtin_cconst! '__GNUC__'
* __builtin_cinit!(STMT)
STMT are writtein in auto-generated code.
This code does not return any value.
Usage:
__builtin_cinit! '#include <zlib.h>'
def no_compression?
__builtin_cconst! 'Z_NO_COMPRESSION ? Qtrue : Qfalse'
end