The mruby C style places `else` on its own line. Reformat the
remaining `} else {` / `} else if (...)` occurrences.
Co-authored-by: Claude <noreply@anthropic.com>
By adding a fast-path where we ignore boxed types we can gain a pretty substantial speedup of mrb_iv_get, making it about 25% faster during a standard optcarrot benchmark run.
NOTE: It is just mrb_iv_get that is that much faster, the whole benchmark seems to be about 3-5% faster with word boxing.
It seems to be preferable to be able to handle pointers of type `char` as well.
For this purpose, `mrb_nanbox_tt_inline` has been reorganized.
- `MRB_NANBOX_TT_POINTER` has been split into `MRB_NANBOX_TT_OBJECT` and `MRB_NANBOX_TT_CPTR`
- `MRB_NANBOX_TT_SYMBOL` has been merged into `MRB_NANBOX_TT_MISC`
```console
% c++ -xc++ -std=c++03 -S -Iinclude -DMRB_NAN_BOXING -DMRB_NO_PRESYM -o- src/array.c > /dev/null
In file included from src/array.c:7:
In file included from include/mruby.h:115:
In file included from include/mruby/value.h:201:
include/mruby/boxing_nan.h:95:12: error: cannot initialize return object of type 'enum mrb_vtype' with an rvalue of type 'int'
return (enum mrb_vtype)(o.u >> 8) & 0x1f;
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
```
The Difference
Since Ruby1.9, the keyword arguments were emulated by Ruby using the hash
object at the bottom of the arguments. But we have gradually moved toward
keyword arguments separated from normal (positinal) arguments.
At the same time, we value compatibility, so that Ruby3.0 keyword
arguments are somewhat compromise. Basically, keyword arguments are
separated from positional arguments, except when the method does not
take any formal keyword arguments, given keyword arguments (packed
in the hash object) are considered as the last argument.
And we also allow non symbol keys in the keyword arguments. In that
case, those keys are just passed in the `**` hash (or raise
`ArgumentError` for unknown keys).
The Instruction Changes
We have changed `OP_SEND` instruction. `OP_SEND` instruction used to
take 3 operands, the register, the symbol, the number of (positional)
arguments. The meaning of the third operand has been changed. It is now
considered as `n|(nk<<4)`, where `n` is the number of positional
arguments, and `nk` is the number of keyword arguments, both occupies
4 bits in the operand.
The number `15` in both `n` and `nk` means variable sized arguments are
packed in the object. Positional arguments will be packed in the array,
and keyword arguments will be packed in the hash object. That means
arguments more than 14 values are always packed in the object.
Arguments information for other instructions (`OP_SENDB` and `OP_SUPER`)
are also changed. It works as the third operand of `OP_SEND`. the
difference between `OP_SEND` and `OP_SENDB` is just trivial. It assigns
`nil` to the block hidden arguments (right after arguments).
The instruction `OP_SENDV` and `OP_SENDVB` are removed. Those
instructions are replaced by `OP_SEND` and `OP_SENDB` respectively with
the `15` (variable sized) argument information.
Calling Convention
When calling a method, the stack elements shall be in the order of the
receiver of the method, positional arguments, keyword arguments and the
block argument. If the number of positional or keyword arugument (`n` or
`nk`) is zero, corresponding arguments will be empty. So when `n=0` and
`nk=0` the stack layout (from bottom to top) will be:
+-----------------------+
| recv | block (or nil) |
+-----------------------+
The last elements `block` should be explicitly filled before `OP_SEND`
or assigned to `nil` by `OP_SENDB` internally. In other words, the
following have exactly same behavior:
OP_SENDB clears `block` implicitly:
```
OP_SENDB reg sym 0
```
OP_SEND clears `block` implicitly:
```
OP_LOADNIL R2
OP_SEND R2 sym 0
```
When calling a method with only positional arguments (n=0..14) without
keyword arguments, the stack layout will be like following:
+--------------------------------------------+
| recv | arg1 | ... | arg_n | block (or nil) |
+--------------------------------------------+
When calling a method with arguments packed in the array (n=15) which
means argument splat (*) is used in the actual arguments, or more than
14 arguments are passed the stack layout will be like following:
+-------------------------------+
| recv | array | block (or nil) |
+-------------------------------+
The number of the actual arguments is determined by the length of the
argument array.
When keyword arguments are given (nk>0), keyword arguments are passed
between positional arguments and the block argument. For example, when
we pass one positional argument `1` and one keyword argument `a: 2`,
the stack layout will be like:
+------------------------------------+
| recv | 1 | :a | 2 | block (or nil) |
+------------------------------------+
Note that keyword arguments consume `2*nk` elements in the stack when
`nk=0..14` (unpacked).
When calling a method with keyword arguments packed in the hash object
(nk=15) which means keyword argument splat (**) is used or more than
14 keyword arguments in the actual arguments, the stack layout will
be like:
+------------------------------+
| recv | hash | block (or nil) |
+------------------------------+
Note for mruby/c
When mruby/c authors try to support new keyword arguments, they need
to handle the new meaning of the argument information operand. If they
choose not to support keyword arguments in mruby/c, it just raise
error when `nk` (taken by `(c>>4)&0xf`) is not zero. And combine
`OP_SENDV` behavior with `OP_SEND` when `n` is `15`.
If they want to support keyword arguments seriously, contact me at
<matz@ruby.or.jp> or `@yukihiro_matz`. I can help you.
If it gives clang-11.0 `-Wembedded-directive`, a warning will be reported in `include/mruby/boxing_nan.h`.
```
include/mruby/boxing_nan.h:48:2: warning: embedding a directive within macro arguments has undefined behavior [-Wembedded-directive]
include/mruby/boxing_nan.h:52:2: warning: embedding a directive within macro arguments has undefined behavior [-Wembedded-directive]
```
The cause of this is #5117.
ref. e993b83c50
- Integrate `Fixnum` and `Integer`
- Remove `Integral`
- `int / int -> int`
- Replace `mrb_fixnum()` to `mrb_int()`
- Replace `mrb_fixnum_value()` to `mrb_int_value()`.
- Use `mrb_integer_p()` instead of `mrb_fixnum_p()`
- `MRB_WITHOUT_FLOAT` => `MRB_NO_FLOAT`
- `MRB_USE_FLOAT` => `MRB_USE_FLOAT32`
The former is to use `USE_XXX` naming convention. The latter is to make
sure `float` is 32bit float and not floating point number in general.
Changes:
- `pool format is completely replaced
- supported types: `STR`, `INT32`, `INT64`, `FLOAT`
- `FLOAT` may be replaced by binary representation in the future
- insert `NUL` after string literals in `mrb` files
- `irep->pool` no longer store values in `mrb_value`
- instead it stores in `mrb_pool_value`
- less allocation
- `mrb_irep` can be stored in ROM
Previously, if `MRB_NAN_BOXING` is defined, for example,
`mrb_cptr_value()` could not keep an odd address.
If it is `MRB_32BIT`, it can be embedded in `NaN` as it is.
If it is `MRB_64BIT`, some operations are shared with `MRB_WORD_BOXING`.
In this case, the MRB_API function `mrb_nan_boxing_cptr_value()` is
defined.
The changes at b2c3d88f were inappropriate because the memory layout of bit
fields are implementation defined. Therefor, I fixed it not to use bit
fields.
Definition of boxed pointer is following:
`111111111111TTTT TTPPPPPPPPPPPPPP PPPPPPPPPPPPPPPP PPPPPPPPPPPPPPPP`
Previously, only the last 32-bit were set, and remaining 14 bits were zeroed when setting `ttt`.