From 667f47abecc13e8a47181f338e727d95e57a6354 Mon Sep 17 00:00:00 2001 From: Robert Pluim Date: Fri, 24 Jan 2020 14:11:44 +0100 Subject: [PATCH] Don't attempt to cache glyph metrics for FONT_INVALID_CODE This was causing massive slowdown in redisplay when eg #xfe0f (VARIATION SELECTOR-16) was present, as the cache ended up very large, unused, and being recreated on every call to font_fill_lglyph_metrics (Bug#39133). * src/composite.c (fill_gstring_body): Hoist FONT_OBJECT_P check out of loop. Calculate glyph code and check for FONT_INVALID_CODE before calling font_fill_lglyph_metrics. Pass glyph code to it. * src/font.c (font_fill_lglyph_metrics): Add code parameter, move glyph code calculation up the call stack into fill_gstring_body. * src/font.h: Adjust font_fill_lglyph_metrics prototype. --- src/composite.c | 18 ++++++++++++++---- src/font.c | 4 +--- src/font.h | 2 +- 3 files changed, 16 insertions(+), 8 deletions(-) diff --git a/src/composite.c b/src/composite.c index 53e6930b5f..364d5c9316 100644 --- a/src/composite.c +++ b/src/composite.c @@ -818,6 +818,11 @@ fill_gstring_body (Lisp_Object gstring) Lisp_Object header = AREF (gstring, 0); ptrdiff_t len = LGSTRING_CHAR_LEN (gstring); ptrdiff_t i; + struct font *font = NULL; + unsigned int code; + + if (FONT_OBJECT_P (font_object)) + font = XFONT_OBJECT (font_object); for (i = 0; i < len; i++) { @@ -832,10 +837,15 @@ fill_gstring_body (Lisp_Object gstring) LGLYPH_SET_FROM (g, i); LGLYPH_SET_TO (g, i); LGLYPH_SET_CHAR (g, c); - if (FONT_OBJECT_P (font_object)) - { - font_fill_lglyph_metrics (g, font_object); - } + + if (font != NULL) + code = font->driver->encode_char (font, LGLYPH_CHAR (g)); + else + code = FONT_INVALID_CODE; + if (code != FONT_INVALID_CODE) + { + font_fill_lglyph_metrics (g, font, code); + } else { int width = XFIXNAT (CHAR_TABLE_REF (Vchar_width_table, c)); diff --git a/src/font.c b/src/font.c index bb39aef92d..2a45630061 100644 --- a/src/font.c +++ b/src/font.c @@ -4416,10 +4416,8 @@ DEFUN ("clear-font-cache", Fclear_font_cache, Sclear_font_cache, 0, 0, 0, void -font_fill_lglyph_metrics (Lisp_Object glyph, Lisp_Object font_object) +font_fill_lglyph_metrics (Lisp_Object glyph, struct font *font, unsigned int code) { - struct font *font = XFONT_OBJECT (font_object); - unsigned code = font->driver->encode_char (font, LGLYPH_CHAR (glyph)); struct font_metrics metrics; LGLYPH_SET_CODE (glyph, code); diff --git a/src/font.h b/src/font.h index 0561e3c83f..8614e7fa10 100644 --- a/src/font.h +++ b/src/font.h @@ -886,7 +886,7 @@ valid_font_driver (struct font_driver const *d) extern Lisp_Object font_range (ptrdiff_t, ptrdiff_t, ptrdiff_t *, struct window *, struct face *, Lisp_Object); -extern void font_fill_lglyph_metrics (Lisp_Object, Lisp_Object); +extern void font_fill_lglyph_metrics (Lisp_Object, struct font *, unsigned int); extern Lisp_Object font_put_extra (Lisp_Object font, Lisp_Object prop, Lisp_Object val); -- 2.23.0