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.
Get rid of these redundant and useless warnings.
```
$ ruby -e 'def bar(a) a; end; def foo(...) bar(...) end; foo({})'
-e:1: warning: The last argument is used as the keyword parameter
-e:1: warning: for `foo' defined here
-e:1: warning: The keyword argument is passed as the last hash parameter
-e:1: warning: for `bar' defined here
```
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.
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.
`freeze_string` essentially called iseq_add_mark_object_compile_time. I
need to know where all writes occur on the `rb_iseq_t`, so this commit
separates the function calls so we can add write barriers in the right
place.
Move the "add mark object" function to the location where we should be
calling RB_OBJ_WRITTEN. I'm going to add verification code next so we
can make sure the objects we're adding to the array are also reachable
from the mark function.
This makes it consistent with calling private attribute assignment
methods, which currently is allowed (e.g. `self.value =`).
Calling a private method in this way can be useful when trying to
assign the return value to a local variable with the same name.
[Feature #11297] [Feature #16123]
The output of RubyVM::InstructionSequence#to_binary is extremely large.
We have reduced the output of #to_binary by more than 70%.
The execution speed of RubyVM::InstructionSequence.load_from_binary is about 7% slower, but when reading a binary from a file, it may be faster than the master.
Since Bootsnap gem uses #to_binary, this proposal reduces the compilation cache size of Rails projects to about 1/4.
See details: [Feature #16163]
RubyVM::InstructionSequence.to_binary generates a bytecode binary
representation. To check compatibility with binary and loading
MRI we prepared major/minor version and compare them at loading
time. However, development version of MRI can change this format
but we can not increment minor version to make them consistent
with Ruby's major/minor versions.
To solve this issue, we introduce new minor version scheme
(binary's minor_version = ruby's minor * 10000 + dev ver)
and we can check incompatibility with older dev version.
The original code looks unnecessarily complicated (to me).
Also, it creates a pre-allocated array only for the prefix of the array.
The new code optimizes not only the prefix but also the subsequence that
is longer than 0x40 elements.
# not optimized
10000000.times { [1+1, 1,2,3,4,...,63] } # 2.12 sec.
# (1+1; push 1; push 2; ...; puts 63; newarray 64; concatarray)
# optimized
10000000.times { [1+1, 1,2,3,4,...,63,64] } # 1.46 sec.
# (1+1; newarray 1; putobject [1,2,3,...,64]; concatarray)
"popped" case can be so simple, so this change moves the branch to the
first, instead of scattering `if (popped)` branches to the main part.
Also, the return value "len" is not used. So it returns just 0 or 1.
compile_list was for the compilation of Array literal and Hash literal.
I guess it was originally reasonable to handle them in one function, but
now, compilation of Array is very different from Hash. So the function
was complicated by many branches for Array and Hash.
This change separates the function to two ones for Array and Hash.
An array literal [1,2,...,301] was compiled to the following iseq:
duparray [1,2,...,300]
putobject [301]
concatarray
The Array literal optimization took every two elements maybe because it
must handle not only Array but also Hash.
Now the optimization takes each element if it is an Array literal. So
the new iseq is: duparray [1,2,...,301].
`[{}, {}, {}, ..., {}, *{}]` is wrongly created.
A big array literal is created and concatenated for every 256 elements.
The newarraykwsplat must be emitted only at the last chunk.
and NODE_ZARRAY to NODE_ZLIST.
NODE_ARRAY is used not only by an Array literal, but also the contents
of Hash literals, method call arguments, dynamic string literals, etc.
In addition, the structure of NODE_ARRAY is a linked list, not an array.
This is very confusing, so I believe `NODE_LIST` is a better name.
Previously, **{} was removed by the parser:
```
$ ruby --dump=parse -e '{**{}}'
@ NODE_SCOPE (line: 1, location: (1,0)-(1,6))
+- nd_tbl: (empty)
+- nd_args:
| (null node)
+- nd_body:
@ NODE_HASH (line: 1, location: (1,0)-(1,6))*
+- nd_brace: 1 (hash literal)
+- nd_head:
(null node)
```
Since it was removed by the parser, the compiler did not know
about it, and `m(**{})` was therefore treated as `m()`.
This modifies the parser to not remove the `**{}`. A simple
approach for this is fairly simple by just removing a few
lines from the parser, but that would cause two hash
allocations every time it was used. The approach taken here
modifies both the parser and the compiler, and results in `**{}`
not allocating any hashes in the usual case.
The basic idea is we use a literal node in the parser containing
a frozen empty hash literal. In the compiler, we recognize when
that is used, and if it is the only keyword present, we just
push it onto the VM stack (no creation of a new hash or merging
of keywords). If it is the first keyword present, we push a
new empty hash onto the VM stack, so that later keywords can
merge into it. If it is not the first keyword present, we can
ignore it, since the there is no reason to merge an empty hash
into the existing hash.
Example instructions for `m(**{})`
Before (note ARGS_SIMPLE):
```
== disasm: #<ISeq:<main>@-e:1 (1,0)-(1,7)> (catch: FALSE)
0000 putself ( 1)[Li]
0001 opt_send_without_block <callinfo!mid:m, argc:0, FCALL|ARGS_SIMPLE>, <callcache>
0004 leave
```
After (note putobject and KW_SPLAT):
```
== disasm: #<ISeq:<main>@-e:1 (1,0)-(1,7)> (catch: FALSE)
0000 putself ( 1)[Li]
0001 putobject {}
0003 opt_send_without_block <callinfo!mid:m, argc:1, FCALL|KW_SPLAT>, <callcache>
0006 leave
```
Example instructions for `m(**h, **{})`
Before and After (no change):
```
== disasm: #<ISeq:<main>@-e:1 (1,0)-(1,12)> (catch: FALSE)
0000 putself ( 1)[Li]
0001 putspecialobject 1
0003 newhash 0
0005 putself
0006 opt_send_without_block <callinfo!mid:h, argc:0, FCALL|VCALL|ARGS_SIMPLE>, <callcache>
0009 opt_send_without_block <callinfo!mid:core#hash_merge_kwd, argc:2, ARGS_SIMPLE>, <callcache>
0012 opt_send_without_block <callinfo!mid:m, argc:1, FCALL|KW_SPLAT>, <callcache>
0015 leave
```
Example instructions for `m(**{}, **h)`
Before:
```
== disasm: #<ISeq:<main>@-e:1 (1,0)-(1,12)> (catch: FALSE)
0000 putself ( 1)[Li]
0001 putspecialobject 1
0003 newhash 0
0005 putself
0006 opt_send_without_block <callinfo!mid:h, argc:0, FCALL|VCALL|ARGS_SIMPLE>, <callcache>
0009 opt_send_without_block <callinfo!mid:core#hash_merge_kwd, argc:2, ARGS_SIMPLE>, <callcache>
0012 opt_send_without_block <callinfo!mid:m, argc:1, FCALL|KW_SPLAT>, <callcache>
0015 leave
```
After (basically the same except for the addition of swap):
```
== disasm: #<ISeq:<main>@-e:1 (1,0)-(1,12)> (catch: FALSE)
0000 putself ( 1)[Li]
0001 newhash 0
0003 putspecialobject 1
0005 swap
0006 putself
0007 opt_send_without_block <callinfo!mid:h, argc:0, FCALL|VCALL|ARGS_SIMPLE>, <callcache>
0010 opt_send_without_block <callinfo!mid:core#hash_merge_kwd, argc:2, ARGS_SIMPLE>, <callcache>
0013 opt_send_without_block <callinfo!mid:m, argc:1, FCALL|KW_SPLAT>, <callcache>
0016 leave
```