Re: [PATCH v2 15/16] Remove local_flags array in struct buffer

[Eli Zaretskii]

> From: Spencer Baugh <sbaugh@catern.com>
> Date: Sat, 21 Nov 2020 21:34:44 -0500
> Cc: Spencer Baugh <sbaugh@catern.com>, Arnold Noronha <arnold@tdrhq.com>,
>  Stefan Monnier <monnier@iro.umontreal.ca>, Dmitry Gutov <dgutov@yandex.ru>
> 
> +#define BVAR_DIRECT(buf, field) ((buf)->field ## _)

I think I'd prefer to call this BVAL instead.  Or maybe leave this
BVAR and rename the getter to something else.

> @@ -963,8 +958,6 @@ reset_buffer (register struct buffer *b)
>    bset_display_count (b, make_fixnum (0));
>    bset_display_time (b, Qnil);
>    bset_enable_multibyte_characters (b, Qt);
> -  bset_cursor_type (b, BVAR (&buffer_defaults, cursor_type));
> -  bset_extra_line_spacing (b, BVAR (&buffer_defaults, extra_line_spacing));

Why are we removing these two?

> @@ -1238,7 +1231,7 @@ buffer_local_value (Lisp_Object variable, Lisp_Object 
> buffer)
>        {
>       lispfwd fwd = SYMBOL_FWD (sym);
>       if (BUFFER_OBJFWDP (fwd))
> -       result = per_buffer_value (buf, XBUFFER_OBJFWD (fwd)->offset);
> +          result = bvar_get (buf, XBUFFER_OBJFWD (fwd)->offset);

Indentation whitespace changes again.

> +INLINE Lisp_Object
> +bvar_get (struct buffer *b, ptrdiff_t offset)
> +{
> +  Lisp_Object val = per_buffer_value (b, offset);
> +  return EQ (val, Qunbound)
> +    ? per_buffer_default (offset)
> +    : val;
>  }

Ouch! an inline function that calls another inline function, instead
of a simple pointer dereference.  Now I'm _really_ worried about the
effect on performance.

Can we make this faster, especially in unoptimized builds?