Prefer inline functions in character.h

In character.h, replace macros with inline functions or enums
when this is easy.  This improves maintainability and
on my platform (Fedora 31 x86-64, gcc -O2) improved CPU
performance very slightly (0.3%) on ‘make compile-always’.
* src/buffer.h (SANE_TAB_WIDTH, CHARACTER_WIDTH):
Move here from character.h, and make them inline functions.
Tune CHARACTER_WIDTH so that ASCII_CHAR_WIDTH is no longer needed.
(sanitize_tab_width, sanitize_char_width):
Move here from character.h.
* src/character.h (MAX_CHAR, MAX_UNICODE_CHAR, MAX_1_BYTE_CHAR)
(MAX_2_BYTE_CHAR, MAX_3_BYTE_CHAR, MAX_4_BYTE_CHAR)
(MAX_5_BYTE_CHAR, MIN_MULTIBYTE_LEADING_CODE)
(MAX_MULTIBYTE_LEADING_CODE, MAX_MULTIBYTE_LENGTH):
Now enum constants instead of macros.
* src/character.h (CHAR_BYTES): Redo to avoid conditional branches.
(CHAR_BYTE8_P, BYTE8_TO_CHAR, UNIBYTE_TO_CHAR, CHAR_TO_BYTE8)
(CHAR_TO_BYTE_SAFE, CHAR_BYTE8_HEAD_P, CHARACTERP)
(CHECK_CHARACTER, CHECK_CHARACTER_CAR, CHECK_CHARACTER_CDR)
(CHAR_PRINTABLE_P, CHAR_BYTES, CHAR_LEADING_CODE, BYTE8_STRING)
(LEADING_CODE_P, TRAILING_CODE_P, CHAR_HEAD_P)
(BYTES_BY_CHAR_HEAD):
Now inline functions instead of macros.
(ASCII_CHAR_WIDTH): Remove; no longer used.
* src/conf_post.h (ATTRIBUTE_PURE): New macro.
* src/lisp.h (char_table_ref): Use it, for better inlining.
* src/fns.c (base64_decode_1): Add now-necessary casts.

1 files changed, 39 insertions, 0 deletions

diff --git a/src/buffer.h b/src/buffer.h
index abb1294d038..9875b8a447b 100644
--- a/src/buffer.h
+++ b/src/buffer.h
@@ -1523,6 +1523,45 @@ lowercasep (int c)
   return !uppercasep (c) && upcase (c) != c;
 }
 
+/* Return a non-outlandish value for the tab width.  */
+
+INLINE int
+sanitize_tab_width (Lisp_Object width)
+{
+  return (FIXNUMP (width) && 0 < XFIXNUM (width) && XFIXNUM (width) <= 1000
+          ? XFIXNUM (width) : 8);
+}
+
+INLINE int
+SANE_TAB_WIDTH (struct buffer *buf)
+{
+  return sanitize_tab_width (BVAR (buf, tab_width));
+}
+
+/* Return a non-outlandish value for a character width.  */
+
+INLINE int
+sanitize_char_width (EMACS_INT width)
+{
+  return 0 <= width && width <= 1000 ? width : 1000;
+}
+
+/* Return the width of character C.  The width is measured by how many
+   columns C will occupy on the screen when displayed in the current
+   buffer.  The name CHARACTER_WIDTH avoids a collision with <limits.h>
+   CHAR_WIDTH.  */
+
+INLINE int
+CHARACTER_WIDTH (int c)
+{
+  return (0x20 <= c && c < 0x7f ? 1
+          : 0x7f < c ? (sanitize_char_width
+                        (XFIXNUM (CHAR_TABLE_REF (Vchar_width_table, c))))
+          : c == '\t' ? SANE_TAB_WIDTH (current_buffer)
+          : c == '\n' ? 0
+          : !NILP (BVAR (current_buffer, ctl_arrow)) ? 2 : 4);
+}
+
 INLINE_HEADER_END
 
 #endif /* EMACS_BUFFER_H */