Basically, this makes the structure of buffer-local values and object
forwarding explicit in the type of Lisp_Symbols rather than use
special Lisp_Objects for that. This tends to lead to slightly more
verbose code, but is more C-like, simpler, and makes it easier to make
sure we handled all cases, among other things by letting the compiler
help us check it.
* lisp.h (enum Lisp_Misc_Type, union Lisp_Misc):
Removing forwarding objects.
(enum Lisp_Fwd_Type, enum symbol_redirect, union Lisp_Fwd): New types.
(struct Lisp_Symbol): Make the various forms of variable-forwarding
explicit rather than hiding them inside Lisp_Object "values".
(XFWDTYPE): New macro.
(XINTFWD, XBOOLFWD, XOBJFWD, XKBOARD_OBJFWD): Redefine.
(XBUFFER_LOCAL_VALUE): Remove.
(SYMBOL_VAL, SYMBOL_ALIAS, SYMBOL_BLV, SYMBOL_FWD, SET_SYMBOL_VAL)
(SET_SYMBOL_ALIAS, SET_SYMBOL_BLV, SET_SYMBOL_FWD): New macros.
(SYMBOL_VALUE, SET_SYMBOL_VALUE): Remove.
(struct Lisp_Intfwd, struct Lisp_Boolfwd, struct Lisp_Objfwd)
(struct Lisp_Buffer_Objfwd, struct Lisp_Kboard_Objfwd):
Remove the Lisp_Misc_* header.
(struct Lisp_Buffer_Local_Value): Redefine.
(BLV_FOUND, SET_BLV_FOUND, BLV_VALUE, SET_BLV_VALUE): New macros.
(struct Lisp_Misc_Any): Add filler to get the right size.
(struct Lisp_Free): Use struct Lisp_Misc_Any rather than struct
Lisp_Intfwd.
(DEFVAR_LISP, DEFVAR_LISP_NOPRO, DEFVAR_BOOL, DEFVAR_INT)
(DEFVAR_KBOARD): Allocate a forwarding object.
* data.c (do_blv_forwarding, store_blv_forwarding): New macros.
(let_shadows_global_binding_p): New function.
(union Lisp_Val_Fwd): New type.
(make_blv): New function.
(swap_in_symval_forwarding, indirect_variable, do_symval_forwarding)
(store_symval_forwarding, swap_in_global_binding, Fboundp)
(swap_in_symval_forwarding, find_symbol_value, Fset)
(let_shadows_buffer_binding_p, set_internal, default_value)
(Fset_default, Fmake_variable_buffer_local, Fmake_local_variable)
(Fkill_local_variable, Fmake_variable_frame_local)
(Flocal_variable_p, Flocal_variable_if_set_p)
(Fvariable_binding_locus):
* xdisp.c (select_frame_for_redisplay):
* lread.c (Fintern, Funintern, init_obarray, defvar_int)
(defvar_bool, defvar_lisp_nopro, defvar_lisp, defvar_kboard):
* frame.c (store_frame_param):
* eval.c (Fdefvaralias, Fuser_variable_p, specbind, unbind_to):
* bytecode.c (Fbyte_code) <varref, varset>: Adapt to the new symbol
value structure.
* buffer.c (PER_BUFFER_SYMBOL): Move from buffer.h.
(clone_per_buffer_values): Only adjust markers into the current buffer.
(reset_buffer_local_variables): PER_BUFFER_IDX is never -2.
(Fbuffer_local_value, set_buffer_internal_1)
(swap_out_buffer_local_variables):
Adapt to the new symbol value structure.
(DEFVAR_PER_BUFFER): Allocate a Lisp_Buffer_Objfwd object.
(defvar_per_buffer): Take a new arg for the fwd object.
(buffer_lisp_local_variables): Return a proper alist (different fix
for bug#4138).
* alloc.c (Fmake_symbol): Use SET_SYMBOL_VAL.
(Fgarbage_collect): Don't handle buffer_defaults specially.
(mark_object): Handle new symbol value structure rather than the old
special Lisp_Misc_* objects.
(gc_sweep) <symbols>: Free also the buffer-local-value objects.
* term.c (set_tty_color_mode):
* bidi.c (bidi_initialize): Don't access the ->value field directly.
* buffer.h (PER_BUFFER_VAR_OFFSET): Don't bother with
a buffer_local_flags.
* print.c (print_object): Get rid of impossible forwarding objects.
* lisp.h (make_pure_string): String pointer arg now points to const.
* alloc.c (find_string_data_in_pure, make_pure_string): String pointer
args now point to const.
* lisp.h (USE_2_TAGS_FOR_INTS): New macro.
(LISP_INT_TAG, case_Lisp_Int, LISP_STRING_TAG, LISP_INT_TAG_P): New macros.
(enum Lisp_Type): Use them. Give explicit values.
(Lisp_Type_Limit): Remove.
(XINT, XUINT, make_number) [!USE_LISP_UNION_TYPE]:
(MOST_NEGATIVE_FIXNUM, MOST_POSITIVE_FIXNUM, INTMASK):
Pay attention to USE_2_TAGS_FOR_INTS.
(INTEGERP): Use LISP_INT_TAG_P.
* fns.c (internal_equal): Simplify the default case.
(sxhash): Use case_Lisp_Int.
* data.c (wrong_type_argument): Don't check against Lisp_Type_Limit any more.
(Ftype_of): Use case_Lisp_Int.
(store_symval_forwarding): Take into account the fact that Ints can
now have more than one tag.
* buffer.c (syms_of_buffer): Use LISP_INT_TAG.
buffer_slot_type_mismatch):
* xfaces.c (face_attr_equal_p):
* print.c (print_object):
* alloc.c (mark_maybe_object, mark_object, survives_gc_p): Use case_Lisp_Int.
(XFLOAT_INIT): New macro for storing a float value.
* alloc.c (make_float, make_pure_float): Use XFLOAT_INIT.
* fns.c (sxhash): Copy out the value of a float in order to examine its bytes.
* dbusbind.c (xd_append_arg): Likewise.
* termhooks.h (P_): Remove redundant def.
(struct terminal): New field `image_cache'.
* frame.h (FRAME_IMAGE_CACHE): New macro. Use it everywhere in place
of FRAME_X_IMAGE_CACHE.
* xterm.h (struct x_display_info): Remove image_cache field.
(FRAME_X_IMAGE_CACHE): Remove. Use FRAME_IMAGE_CACHE instead.
* w32term.h (struct w32_display_info): Remove image_cache field.
(FRAME_X_IMAGE_CACHE): Remove. Use FRAME_IMAGE_CACHE instead.
* macterm.h (struct mac_display_info): Remove image_cache field.
(FRAME_X_IMAGE_CACHE): Remove. Use FRAME_IMAGE_CACHE instead.
* xterm.c (x_term_init):
* w32term.c (w32_term_init):
* macterm.c (mac_term_init): Set the image_cache in the terminal.
* dispextern.h (clear_image_cache, forall_images_in_image_cache):
Remove declarations.
(clear_image_caches, mark_image_cache): New declarations.
* xfaces.c (clear_face_cache):
* xdisp.c (redisplay_internal): Use clear_image_caches.
* image.c (clear_image_cache): Don't check that a frame is on
a window-system before checking if it shares the same cache.
(clear_image_caches): New function.
(Fclear_image_cache): Use it.
(mark_image): Move from allo.c.
(mark_image_cache): Move from alloc.c and forall_images_in_image_cache.
* alloc.c (mark_image, mark_image_cache): Move to image.c.
(mark_object): Don't call mark_image_cache for frames.
(mark_terminals): Call mark_image_cache.
(allocate_pseudovector): Make non-static.
* lisp.h (enum pvec_type): New tag PVEC_OTHER.
(allocate_pseudovector): Declare.
(ALLOCATE_PSEUDOVECTOR): Move from alloc.c
(XMISCANY): New macro.
(XMISCTYPE): Use it.
(struct Lisp_Misc_Any): New type.
(union Lisp_Misc): Use it.
(struct Lisp_Buffer_Local_Value): Add `local_if_set' bit.
* data.c (Fboundp, store_symval_forwarding, swap_in_global_binding)
(find_symbol_value, set_internal, default_value, Fset_default)
(Fmake_variable_buffer_local, Fmake_local_variable)
(Fkill_local_variable, Fmake_variable_frame_local, Flocal_variable_p)
(Flocal_variable_if_set_p, Fvariable_binding_locus):
The SOME_BUFFER_LOCAL_VALUEP distinction is replaced by local_if_set.
* alloc.c (allocate_buffer): Set the size and tag.
(allocate_misc, mark_maybe_object, mark_object, survives_gc_p):
Use XMISCANY.
(die): Follow the GNU convention for error messages.
* print.c (print_object): SOME_BUFFER_LOCAL_VALUEP -> local_if_set.
* buffer.c (Fget_buffer_create, Fmake_indirect_buffer): Don't set the
tag any more.
(set_buffer_internal_1):
* frame.c (store_frame_param):
* eval.c (specbind):
* xdisp.c (select_frame_for_redisplay): Drop SOME_BUFFER_LOCAL_VALUEP.