pool strings generated by mrbc -C are C string literals inside
static const structs, which reside in ROM. mark them as
IREP_TT_SSTR (static) instead of IREP_TT_STR (dynamic) so the
VM uses mrb_str_new_static() and mrb_intern_static() instead of
mrb_str_new() and mrb_intern(). this avoids unnecessary
malloc+memcpy for string literals longer than the embed threshold,
especially on embedded platforms where mrb_ro_data_p() returns
FALSE.
Co-authored-by: Claude <noreply@anthropic.com>
replace lossy 2-bit truncation with rotation-based encoding for
32-bit + MRB_USE_FLOAT32, matching the technique used for 64-bit
float64. rotl32(bits - ADDEND, 3) maps biased exponents [95, 158]
(actual [-32, +31]) to properly tagged inline values with zero
precision loss. special values (0, Inf, NaN) use sentinel constants;
out-of-range floats fall back to heap-allocated RFloat.
also fix a pre-existing alignment issue: RVALUE was 20 bytes on
32-bit, causing 4-byte-aligned objects to be misidentified as
immediates by word boxing (WORDBOX_IMMEDIATE_MASK=0x07 requires
8-byte alignment). pad RVALUE to 24 bytes on 32-bit + float32.
Co-authored-by: Claude <noreply@anthropic.com>
ROM method tables used static mrb_mt_tbl variables shared
across the process. The next pointer in each wrapper was
mutated by mrb_mt_init_rom(), causing cross-state
contamination when multiple mrb_state instances existed.
Allocate mrb_mt_tbl wrappers per-state via mrb_malloc().
The const mrb_mt_entry[] arrays remain static and shared.
Wrappers are tracked in mrb->rom_mt and freed at mrb_close().
Remove MRB_MT_ROM_TAB macro; add MRB_MT_INIT_ROM macro that
auto-computes size and calls the new mrb_mt_init_rom().
Co-authored-by: Claude <noreply@anthropic.com>
Replace check_method_noarg() with check_argument_count() that validates
min <= argc <= max using the full aspec stored in mrb_method_t.flags.
This catches ArgumentError earlier at dispatch time, before entering
the C function.
The old check only handled the special case of aspec==0 (NOARG).
The new check extracts REQ, OPT, REST, POST, KEY, and KDICT from
the aspec and validates accordingly. Keyword hash is counted as
a positional arg only when the method doesn't accept keywords.
Remove MRB_METHOD_NOARG_P macro from proc.h (subsumed by aspec check).
Fix 15 incorrect aspec declarations across the codebase that were
exposed by the stricter enforcement.
Co-authored-by: Claude <noreply@anthropic.com>
Move MRB_METHOD_FUNC_FL to bit 24 and visibility flags to
bits 25-26 so that MRB_ARGS_*() values (bits 0-23) can be
stored directly without shifting. This makes MRB_MT_PRIVATE
and MRB_METHOD_PRIVATE_FL the same value, eliminating the
dual-constant confusion and simplifying the MRB_MT_ENTRY()
macro to a single OR operation.
Co-authored-by: Claude <noreply@anthropic.com>
The NOARG flag (bit 2) is now redundant since the full aspec is
stored in bits 4+ of the flags field. Replace the dedicated bit
check with aspec==0 check. Store aspec in define_method_id() for
dynamically defined methods too.
Co-authored-by: Claude <noreply@anthropic.com>
Restore MRB_ARGS_* argument specs and ISO section comments to all
709 ROM method table entries. The aspec is encoded in bits 4-27 of
the flags field; MRB_MT_NOARG is now auto-derived from aspec==0.
Add MRB_MT_ENTRY_PRIVATE() macro for private methods (53 entries)
and MRB_MT_ASPEC() accessor for extracting aspec from flags.
Co-authored-by: Claude <noreply@anthropic.com>
Move conditional mrb_define_method_id() calls into ROM entry
arrays using #ifdef guards. With linear search, sizeof in
MRB_MT_ROM_TAB() adjusts automatically after preprocessing.
Cross-class ROM tables (methods a gem defines on a class it does
not own) are reverted to mrb_define_method_id(). Multiple gems
should not add ROM table layers to the same class; each layer
costs a 16-byte mrb_mt_tbl struct in RAM and deepens the lookup
chain. Use mrb_define_method_id() for cross-class methods.
Co-authored-by: Claude <noreply@anthropic.com>
Since ROM table entries are always C functions, have the
MRB_MT_ENTRY() macro set MRB_MT_FUNC automatically. This
simplifies entry definitions across all 32 source files.
Co-authored-by: Claude <noreply@anthropic.com>
Replace binary search with linear scan in mt_get(), mt_put(),
mt_del(), mt_chain_has(), and mrb_mt_foreach(). The method cache
makes repeated lookups O(1), so linear scan on cache misses is
acceptable.
This removes the sorting requirement, allowing ROM entry arrays
to be declared const. On embedded systems, const static data
resides in flash/ROM instead of RAM, saving ~8.4KB for ~700
method entries on 32-bit MCUs.
Co-authored-by: Claude <noreply@anthropic.com>
Add a dedicated uint32_t flags field to mrb_mt_entry instead of
packing flags into the lower bits of mrb_sym via MRB_MT_KEY().
The key field now stores the pure symbol ID with no shift.
On 64-bit, the flags field fills the alignment gap after mrb_sym,
so entry size remains 16 bytes (zero overhead). On 32-bit, entry
size grows from 8 to 12 bytes.
This eliminates the risk of symbol ID overflow from the 4-bit
shift, and the flags field can later store aspec (MRB_ARGS_*)
information that was previously discarded.
Co-authored-by: Claude <noreply@anthropic.com>
Replace the parallel-arrays (struct-of-arrays) ROM method table
layout with an array-of-structs layout where each mrb_mt_entry
bundles its function pointer and symbol key together.
New MRB_MT_ENTRY() and MRB_MT_ROM_TAB() macros simplify ROM table
definitions from a 3-part pattern (SIZE define + anonymous struct +
mrb_mt_tbl) to a 2-part pattern (entries array + mrb_mt_tbl).
Internal mt_* functions in class.c are simplified: single memmove/
memcpy operations replace paired key+value operations.
Co-authored-by: Claude <noreply@anthropic.com>
When mrb_mt_init_rom() is called on a class that already has a
mutable method table (from prior mrb_define_method_id() calls),
the mutable top layer is now frozen in place instead of being
left as a writable layer that wastes RAM on embedded systems.
The frozen bit (bit 29 of alloc field) marks heap-allocated
method table layers as temporarily immutable. Unlike the
readonly bit (bit 30, for true ROM), frozen layers are
automatically unfrozen when methods are later added via
mrb_define_method_raw() or removed via mrb_remove_method().
This preserves the c->mt pointer, which is critical because
iclasses (from module inclusion) hold a copy of it.
Co-authored-by: Claude <noreply@anthropic.com>
int_divmod passed an integer mrb_value directly to flo_divmod, which
used mrb_float() to extract the value. In word boxing mode, this caused
a misaligned pointer dereference. Use mrb_ensure_float_type() to safely
convert the integer to float before passing to flo_divmod.
Co-authored-by: Claude <noreply@anthropic.com>
`&nil` is recently introduced in CRuby to explicitly declare that
a method does not accept a block. When a block is passed,
ArgumentError "no block accepted" is raised. This is analogous to
`**nil` for keyword arguments.
The noblock flag is encoded in bit 23 of OP_ENTER's aspec operand
(24=n1:m5:o5:r1:m5:k5:d1:b1), avoiding the need for a new opcode.
Co-authored-by: Claude <noreply@anthropic.com>
Left-shifting a negative int64_t is undefined behavior in C.
Cast to uint64_t before the shift to produce the same bit pattern
using well-defined unsigned arithmetic.
Co-authored-by: Claude <noreply@anthropic.com>
Previously, removing a ROM method required flattening all chain layers
into a single mutable table. This was O(n) and allocated RAM for all
previously-ROM methods.
Use a tombstone marker (MT_FUNC flag with func=NULL) instead. The
mt_get() lookup treats this as "not found" and stops the chain walk,
hiding the ROM entry while allowing superclass lookup.
Co-authored-by: Claude <noreply@anthropic.com>
Presym is now always enabled. Remove #ifndef MRB_NO_PRESYM
guards and their #else fallback branches from all core files.
Co-authored-by: Claude <noreply@anthropic.com>
Move String's 46 method definitions from runtime
mrb_define_method_id() calls to a static ROM method table
sorted at init time. mrb_mt_init_rom() sorts the parallel
vals/keys arrays by presym ID and sets the readonly flag.
Expose mt_tbl and related types in internal.h so ROM tables
can be defined in individual source files.
When MRB_NO_PRESYM is defined, falls back to traditional
runtime method registration.
Co-authored-by: Claude <noreply@anthropic.com>
Add next pointer and readonly flag to mt_tbl struct to support
chained ROM method table layers. mt_get() walks the chain,
mt_copy() shares ROM layers, mt_free() and mrb_gc_mark_mt() skip
readonly layers. COW in mrb_define_method_raw() creates a mutable
top layer when the existing table is readonly. mt_flatten() merges
all layers for the rare remove_method case.
No ROM tables exist yet -- all tables have next==NULL and no
readonly flag, so behavior is identical to the previous code.
Co-authored-by: Claude <noreply@anthropic.com>
Encode 0.0, -0.0, +Inf, -Inf, and NaN as small sentinel constants
with the float tag pattern, avoiding heap allocation for these common
special values. All NaN bit patterns are normalized to a single
canonical NaN. The 5 obscure floats near 2^(-255) whose rotation
encoding would collide with a sentinel are heap-allocated instead.
Co-authored-by: Claude <noreply@anthropic.com>
Replace lossy 2-bit truncation with rotation-based encoding for
64-bit word boxing with float64. The new scheme uses
rotl64(float_bits - ADDEND, 3) to embed floats inline with full
52-bit mantissa precision. Floats with exponents outside [-255,+256]
(0.0, NaN, Inf, very small/large values) fall back to heap-allocated
RFloat.
Co-authored-by: Claude <noreply@anthropic.com>
Add Hash#__pat_values(keys) that returns an array of values if all
keys exist, or false if any key is missing. This replaces per-key
key?() + []() calls (2N hash lookups) with a single method call
(N hash lookups). The compiler generates __pat_values() followed by
array indexing to extract each value for pattern matching.
Co-authored-by: Claude <noreply@anthropic.com>
mrb_get_args(mrb, "*", ...) internally allocates an array when
arguments are on the stack, so passing keys as direct arguments
did not actually avoid allocation. Change __except to take a
single array argument instead, which is simpler and GC-safe.
Co-authored-by: Claude <noreply@anthropic.com>
Add Hash#__except that returns a new hash excluding specified keys,
used by the compiler for **rest capture in hash patterns. Takes keys
as direct arguments to avoid array allocation. The compiler passes
matched key symbols directly on the stack via OP_SEND.
Co-authored-by: Claude <noreply@anthropic.com>
the second NULL in the initializer was for the removed gcnext field,
causing "makes integer from pointer" warning on the tt bitfield.
Co-authored-by: Claude <noreply@anthropic.com>
remove per-object gcnext pointer from MRB_OBJECT_HEADER, saving one
word (8 bytes on 64-bit) per object slot. the gray list for tri-color
marking is replaced by a fixed-size stack (MRB_GRAY_STACK_SIZE=1024)
in mrb_gc. when the stack overflows, a linear heap rescan recovers
gray objects.
object slot size: 48 -> 40 bytes (16.7% reduction on 64-bit).
benchmarks show up to 12% RSS reduction on object-heavy workloads
with neutral performance impact.
Co-authored-by: Claude <noreply@anthropic.com>
Same reasoning as the vm.c change - the keyword hash arriving at
C functions via mrb_get_args() is always freshly constructed at the
call site, so duplication is unnecessary.
Co-authored-by: Claude <noreply@anthropic.com>
The keyword argument hash passed to a method is always freshly
constructed at the call site - either by hash_new_from_regs() in
OP_SEND for inline keyword pairs, or by OP_HASH/OP_HASHCAT for
compiler-generated keyword arguments (including the **h splat case
which creates OP_HASH(0)+OP_HASHCAT). Since no caller retains a
reference to this hash, the mrb_hash_dup() was redundant.
Co-authored-by: Claude <noreply@anthropic.com>
Same issue as the pool string fix: the bounds check for
symbol names only validated snl bytes, but the binary
format includes a null terminator. The source pointer
advances by snl+1, so the check must account for it.
Co-authored-by: Claude <noreply@anthropic.com>
The bounds check for IREP_TT_STR pool data only validated
pool_data_len bytes, but the binary format includes a null
terminator after the string content. Both memcpy and the
source pointer advance by pool_data_len+1, so the check
must account for the extra byte.
Co-authored-by: Claude <noreply@anthropic.com>
Reject MRB_INT_MAX length strings to prevent signed integer overflow
when adding 1 for the null terminator in str_init_normal_capa() and
resize_capa().
Co-authored-by: Claude <noreply@anthropic.com>
Replace per-symbol mrb_malloc() with a chunk-based string pool that
batches allocations into 4KB chunks. This reduces malloc call count
by ~12x (e.g. 909 vs 10,887 for 10k dynamic symbols) and eliminates
per-allocation malloc metadata overhead (~16 bytes/symbol).
Pool allocations are rounded up to even size to preserve LSB pointer
tagging used for literal detection.
Co-authored-by: Claude <noreply@anthropic.com>
Previously, the identity of the proc object was verified solely based on the identity of irep.
This patch makes the behavior consistent with CRuby.
The reason I noticed this issue was that when adding multiple proc objects with the same irep to a set object, only one was added.
```ruby
p Set.new(Array.new(3) { -> {} }).size
# => 3 (Ruby 4.0)
# => 1 (mruby without this patch)
```
If the block scope is the same, there is only one in CRuby as well.
However, in CRuby, the result of `Proc#to_s` is not affected by the block scope, so it has been changed to be based on the object's address.
The reason no test for `Proc#to_s` was added is that I couldn't determine whether it should be based on `Proc#hash` or the object's address.
```ruby
b = []
t = 3
while t > 0
b << -> {}
t -= 1
end
p Set.new(b).size
# => 1 (Ruby 4.0 and mruby)
p b[0].to_s == b[1].to_s
# => false (Ruby 4.0)
# => true (mruby without this patch)
```
These opcodes use BB format instead of BBB, saving 1 byte per call.
In the standard library, this saves ~790 bytes (568 SEND0 + 222 SSEND0).
Co-authored-by: Claude <noreply@anthropic.com>
Change default stack growth from linear (+128) to exponential (1.5x).
This reduces reallocation frequency while maintaining reasonable memory
usage. The minimum growth is still MRB_STACK_GROWTH (128) to ensure
small programs don't over-allocate.
MRB_STACK_EXTEND_DOUBLING (2x growth) remains available for maximum
performance when memory is not a concern.
Co-authored-by: Claude <noreply@anthropic.com>
Yukihiro "Matz" Matsumoto