In preparation for the use of `PVEC_COMPILED` objects for
interpreted functions, rename them to use a more neutral name.
* src/lisp.h (enum pvec_type): Rename `PVEC_COMPILED` to `PVEC_CLOSURE`.
(enum Lisp_Compiled): Use `CLOSURE_` prefix i.s.o `COMPILED_`.
Also use `CODE` rather than `BYTECODE`.
(CLOSUREP): Rename from `COMPILEDP`.
(enum Lisp_Closure): Rename from `Lisp_Compiled`.
* src/alloc.c, src/bytecode.c, src/comp.c, src/data.c, src/eval.c,
* src/fns.c, src/lisp.h, src/lread.c, src/pdumper.c, src/print.c,
* src/profiler.c: Rename all uses accordingly.
* src/.gdbinit (xclosure): Rename from `xcompiled`.
(xcompiled): New obsolete alias.
(xpr): Adjust accordingly. Also adjust to new PVEC_CLOSURE tag name.
* src/bytecode.c (exec_byte_code):
We can safely assume that the immediate argument to varref and varset
is a bare symbol; the byte-compiler should guarantee that.
* src/bytecode.c (exec_byte_code):
Only use fast-path optimisations for calls and dynamic variable
reference and setting where the symbol is plain, which is much faster.
The obsolete lazy-loaded bytecode feature, enabled by
`byte-compile-dynamic`, slows down Lisp execution even when not in use
because every call to a bytecode function has to check that function
for laziness.
This change forces up-front loading of all lazy bytecode so that we
can remove all those checks. (Dynamically loaded doc strings are not
affected.)
There is no point in generating lazy bytecode any more so we stop
doing that; this simplifies the compiler. `byte-compile-dynamic` now
has no effect.
This is a fully compatible change; the few remaining users of
`byte-compile-dynamic` should not notice any difference.
* src/lread.c (bytecode_from_rev_list): Force eager loading of
lazy bytecode.
* src/bytecode.c (exec_byte_code): Remove lazy bytecode checks.
* src/eval.c (fetch_and_exec_byte_code, Ffetch_bytecode): Remove.
(funcall_lambda): Call exec_byte_code directly, avoiding checks.
* lisp/subr.el (fetch-bytecode): New definition, obsolete no-op.
* lisp/emacs-lisp/disass.el (disassemble-1):
* lisp/emacs-lisp/bytecomp.el (byte-compile-unfold-bcf):
Remove calls to fetch-bytecode.
(byte-compile-dynamic): Update doc string.
(byte-compile-close-variables, byte-compile-from-buffer)
(byte-compile-insert-header, byte-compile-output-file-form)
(byte-compile--output-docform-recurse, byte-compile-output-docform)
(byte-compile-file-form-defmumble):
Remove effects of byte-compile-dynamic.
* doc/lispref/compile.texi (Dynamic Loading): Remove node now that
the entire `byte-compile-dynamic` facility has been rendered inert.
* etc/NEWS: Announce changes.
This saves several words in the hash table object at the cost of an
indirection at runtime. This seems to be a gain in overall
performance.
FIXME: We cache hash test objects in a rather clumsy way. A better
solution is sought.
* src/lisp.h (struct Lisp_Hash_Table): Use a pointer to the test
struct. All references adapted.
* src/alloc.c (garbage_collect):
* src/fns.c (struct hash_table_user_test, hash_table_user_tests)
(mark_fns, get_hash_table_user_test): New state for caching test
structs, and functions managing it.
This improves performance in several ways. Separate functions are
used depending on whether the caller has a hash value computed or not.
* src/fns.c (hash_lookup_with_hash, hash_lookup_get_hash): New.
(hash_lookup): Remove hash return argument.
All callers adapted.
hash_lookup_with_hash hash_hash_t arg
Produce synthetic backtrace entries for `aref` and `aset` byte-ops
when the index is non-fixnum, or is out of range for vector or record
arguments (bug#64613).
* src/bytecode.c (exec_byte_code): Detect type and range errors
in-line for aref and aset.
* src/data.c (syms_of_data): Declare symbols Qaref and Qaset.
* test/lisp/emacs-lisp/bytecomp-tests.el
(bytecomp-tests--byte-op-error-cases): Add test cases.
Include calls to these primitives from byte-compiled code in
backtraces. For nth and elt, not all errors are covered.
(Bug#64613)
* src/bytecode.c (exec_byte_code): Add error backtrace records for
car, cdr, setcar, setcdr, nth and elt.
* src/data.c (syms_of_data): Add missing defsyms for car, setcar,
setcdr, nth and elt.
* test/lisp/emacs-lisp/bytecomp-tests.el
(bytecomp-tests--error-frame, bytecomp-tests--byte-op-error-cases)
(bytecomp--byte-op-error-backtrace): New test.
* src/editfns.c (narrow_to_region_internal): New function, which
contains the body previously in 'Fnarrow_to_region' but accepts
a third argument.
(Fnarrow_to_region): Use the new function. Update the docstring.
(Fwiden): Update the docstring.
* src/lisp.h: Prototype of the new function.
* src/xdisp.c (handle_fontified_prop): Use the new function instead
of 'Fnarrow_to_region'.
* src/process.c (Finternal_default_process_filter):
* src/lread.c (readevalloop): Remove the third argument to
'Fnarrow_to_region'.
* src/bytecode.c (exec_byte_code):
* lisp/emacs-lisp/comp.el (comp-limplify-lap-inst):
* lisp/emacs-lisp/bytecomp.el: Restore the statu quo ante.
* etc/NEWS: Remove the entry about the new optional argument.
* doc/lispref/positions.texi (Narrowing): Update the documentation.
* src/editfns.c (Fnarrow_to_region): Add the parameter to the
function, and handle it. Update docstring.
(unwind_locked_begv, unwind_locked_zv): New functions.
(Fwiden): Do nothing when restrictions are locked. Update
docstring.
(syms_of_editfns): Replace the 'inhibit-widen' symbol and variable
with a 'restrictions-locked' symbol and variable. Update docstring.
* src/xdisp.c (handle_fontified_prop): Use Fnarrow_to_region with
the new parameter.
(unwind_narrowed_zv): Remove function.
* src/process.c (Finternal_default_process_filter): Add a third
argument to Fnarrow_to_region.
* src/lread.c (readevalloop): Add a third argument to
Fnarrow_to_region.
* src/bytecode.c (exec_byte_code): Add a third argument to
Fnarrow_to_region.
* etc/NEWS (like): Mention the new parameter of 'narrow-to-region'.
* doc/lispref/positions.texi (Narrowing): Document it.
This is a cosmetic change only; there is no change in behaviour.
* lisp/emacs-lisp/bytecomp.el:
* src/bytecode.c (BYTE_CODES, exec_byte_code):
Update and/or remove incorrect, outdated or useless comments.
Clarify. Reorder where appropriate. Rename Bsave_current_buffer to
Bsave_current_buffer_OBSOLETE and Bsave_current_buffer_1 to
Bsave_current_buffer, reflecting the state since 1996.
* src/lisp.h (lisp_h_Qni): New macro.
(DEFUN): Use it.
* src/alloc.c (syms_of_alloc): Use it.
* src/bytecode.c (Fbyte_code): Fix Lisp_Object/int mixup.
* src/bytecode.c (valid_sp): static, not INLINE, as INLINE
should be used only in headers and between INLINE_HEADER_BEGIN
and INLINE_HEADER_END. No need for ‘inline’ here.
Using a plain C struct instead of type-punning Lisp_Object stack slots
makes the bytecode interpreter code more type-safe and potentially
faster (from better alias analysis), and the special-purpose accessors
are no longer needed. It also reduces the stack requirements when
using 64-bit Lisp_Object on 32-bit platforms.
* src/bytecode.c (enum stack_frame_index)
(sf_get_ptr, sf_set_ptr, sf_get_lisp_ptr, sf_set_lisp_ptr,
sf_get_saved_pc, sf_set_saved_pc): Remove.
(BC_STACK_SIZE): Now in bytes, not Lisp words.
(struct bc_frame): New.
(init_bc_thread, mark_bytecode, Finternal_stack_stats, valid_sp)
(exec_byte_code):
* src/lisp.h (struct handler, get_act_rec, set_act_rec):
Adapt to new struct bc_frame.
* src/bytecode.c (Fbyte_code):
* src/composite.c (Fclear_composition_cache):
Prefer CALLN to doing it by hand.
* src/fns.c (ccall2): Remove. All uses replaced by CALLN.
Use a dedicated stack for bytecode, instead of using the C stack.
Stack frames are managed explicitly and we stay in the same
exec_byte_code activation throughout bytecode function calls and
returns. In other words, exec_byte_code no longer uses recursion
for calling bytecode functions.
This results in better performance, and bytecode recursion is no
longer limited by the size of the C stack. The bytecode stack is
currently of fixed size but overflow is handled gracefully by
signalling a Lisp error instead of the hard crash that we get now.
In addition, GC marking of the stack is now faster and more precise.
Full precision could be attained if desired.
* src/alloc.c (ATTRIBUTE_NO_SANITIZE_ADDRESS): Make non-static.
* src/bytecode.c (enum stack_frame_index, BC_STACK_SIZE)
(sf_get_ptr, sf_set_ptr, sf_get_lisp_ptr, sf_set_lisp_ptr)
(sf_get_saved_pc, sf_set_saved_pc, init_bc_thread, free_bc_thread)
(mark_bytecode, Finternal_stack_stats, valid_sp): New.
(exec_byte_code): Adapt to use the new bytecode stack.
(syms_of_bytecode): Add defsubr.
* src/eval.c (unwind_to_catch): Restore saved stack frame.
(push_handler_nosignal): Save stack frame.
* src/lisp.h (struct handler): Add act_rec member.
(get_act_rec, set_act_rec): New.
* src/thread.c (mark_one_thread): Call mark_bytecode.
(finalize_one_thread): Free bytecode thread state.
(Fmake_thread, init_threads): Set up bytecode thread state.
* src/thread.h (struct bc_thread_state): New.
(struct thread_state): Add bytecode thread state.
Pass the function object and encoded arity, not the other components.
This speeds up several call paths and is necessary for improvements to
come.
* src/bytecode.c (Fbyte_code): Make a new byte code object for
execution. This is slower but performance isn't critical here.
(exec_byte_code): Retrieve components from the passed function.
* src/eval.c (fetch_and_exec_byte_code):
* src/lisp.h (exec_byte_code): Update signature.
* src/bytecode.c (BYTE_CODES, enum byte_code_op, exec_byte_code):
Don't display custom messages in debug mode for Bscan_buffer and
Bset_mark which were removed long ago.
* src/bytecode.c (FETCH2):
Use `|` instead of `+` to combine the bytes forming a 16-bit immediate
argument so that GCC (prior to version 12) recognises the idiom and
generates a 16-bit load. This applies for little-endian machines with
cheap unaligned accesses such as x86[-64], arm64 and power64le.
This 1-character change results in a measurable speed gain on many
kinds of Lisp code, as 16-bit immediates are used by all jump
instructions.
Clang performs this optimisation for both `+` and `|` from version 10.
* src/bytecode.c (exec_byte_code): Inline aref and aset for
vectors and records, since this is important for code that makes heavy
use of arrays and/or objects.
It was implemented but never generated, originally intended for
TCO in the pre-lexbind era (which was semantically dubious anyway).
Removing it speeds up the interpreter because there is no longer any
need for the outermost `count` variable unless checking is enabled.
* lisp/emacs-lisp/bytecomp.el:
* lisp/emacs-lisp/comp.el (comp-limplify-lap-inst):
* src/bytecode.c (BYTE_CODES, exec_byte_code):
Remove definition and implementation of unbind-all, freeing up the opcode
for other purposes.
* src/bytecode.c (exec_byte_code): Perform bytecode unwinding error
check only when building with debugging (NDEBUG not defined, checking
enabled, or BYTE_CODE_SAFE enabled). This improves speed in several
ways.
Since we pass no arguments to a non-lexbind bytecode function, we can
specify its arity as 0 instead of nil and save a test and branch.
* src/bytecode.c (Fbyte_code, exec_byte_code):
* src/eval.c (fetch_and_exec_byte_code, funcall_lambda):
* src/lisp.h:
Change the args_template parameter type to ptrdiff_t, since it is now
always a small integer, in exec_byte_code and
fetch_and_exec_byte_code, all callers adjusted.
Avoid making a copy (in the interpreter C stack frame) of the bytecode
string by making sure it won't be moved by the GC. This is done by
reallocating it to the heap normally only used for large strings,
which isn't compacted.
This requires that we retain an explicit reference to the bytecode
string object (`bytestr`) lest it be GCed away should all other
references vanish during execution. We allocate an extra stack slot
for that, as we already do for the constant vector object.
* src/alloc.c (allocate_string_data): Add `immovable` argument.
(resize_string_data, make_clear_multibyte_string): Use it.
(pin_string): New.
* src/pdumper.c (dump_string): Fix incorrect comment.
Update hash for Lisp_String (only comments changed, not contents).
* src/lread.c (read1):
* src/alloc.c (Fmake_byte_code, purecopy):
* src/bytecode.c (Fbyte_code): Pin bytecode on object creation.
(exec_byte_code): Don't copy bytecode. Retain `bytestr` explicitly.
* src/lisp.h (Lisp_String): Explain special size_byte values.
(string_immovable_p): New.
The function call overhead is nontrivial in comparison to the actual
code which makes this worthwhile.
* src/bytecode.c (exec_byte_code):
Inline code from Fsetcar and Fsetcdr.
Since numeric operations are mostly done on fixnums, this gives a
speed-up for common code.
* src/bytecode.c (exec_byte_code): Inline fixnum comparisons and
operations with fixnum results: =, >, <, <=, >=, -, +, -, *, /, %, max
and min.
Inline parts of the code for function calls to speed up the common
case of calling lexbound byte-code. By eliminating intermediate
functions, this also reduces C stack usage a little.
* src/bytecode.c (exec_byte_code): Inline parts of Ffuncall,
funcall_lambda and fetch_and_exec_byte_code in the Bcall opcode
handler.
* src/eval.c (backtrace_debug_on_exit): Inline and move to lisp.h.
(do_debug_on_call): Make global so that it can be called from
bytecode.c.
(funcall_general): New function, essentially the meat of Ffuncall.
* src/lisp.h (backtrace_debug_on_exit): Moved here from eval.c.
Fchar_syntax did not convert unibyte characters to multibyte when the
current buffer was unibyte, in contrast to `char-syntax` in
byte-compiled code (bug#53260).
* src/bytecode.c (exec_byte_code): Call out to Fchar_syntax;
the dynamic frequency is too low to justify inlining here, and it
did lead to implementations diverging.
* src/syntax.c (Fchar_syntax): Convert non-ASCII unibyte values to
multibyte.
* test/src/syntax-tests.el (syntax-char-syntax): New test.
This simplifies code, and helps performance in some cases (Bug#36597).
* src/lisp.h (hash_rehash_needed_p): Remove. All uses removed.
(hash_rehash_if_needed): Remove. All uses removed.
(struct Lisp_Hash_Table): Remove comment about rehashing hash tables.
* src/pdumper.c (thaw_hash_tables): New function.
(hash_table_thaw): New function.
(hash_table_freeze): New function.
(dump_hash_table): Simplify.
(dump_hash_table_list): New function.
(hash_table_contents): New function.
(Fdump_emacs_portable): Handle hash tables by eager rehashing.
(pdumper_load): Restore hash tables.
(init_pdumper_once): New function.
