drw: minor improvement to the nomatches cache

1. use `unsigned int` to store the codepoints, this avoids waste on
   common case where `long` is 64bits. and POSIX guarantees `int` to be
   at least 32bits so there's no risk of truncation.
2. since switching to `unsigned int` cuts down the memory requirement by
   half, double the cache size from 64 to 128.
3. instead of a linear search, use a simple hash-table for O(1) lookups.

ref.
https://git.suckless.org/dmenu/commit/7ab0cb5ef0e19352fc5d64ae0d57a5cf4540acbf.html
This commit is contained in:
bakkeby 2023-09-22 18:24:09 +02:00
parent c5ed9a9f42
commit 76549d014e
4 changed files with 15 additions and 14 deletions

View File

@ -1,5 +1,5 @@
Similar to [dwm-flexipatch](https://github.com/bakkeby/dwm-flexipatch) this dmenu 5.2 (0fe460d, Similar to [dwm-flexipatch](https://github.com/bakkeby/dwm-flexipatch) this dmenu 5.2 (8df553e,
2023-04-05) project has a different take on patching. It uses preprocessor directives to decide 2023-09-22) project has a different take on patching. It uses preprocessor directives to decide
whether or not to include a patch during build time. Essentially this means that this build, for whether or not to include a patch during build time. Essentially this means that this build, for
better or worse, contains both the patched _and_ the original code. The aim being that you can better or worse, contains both the patched _and_ the original code. The aim being that you can
select which patches to include and the build will contain that code and nothing more. select which patches to include and the build will contain that code and nothing more.

View File

@ -33,7 +33,6 @@
/* macros */ /* macros */
#define INTERSECT(x,y,w,h,r) (MAX(0, MIN((x)+(w),(r).x_org+(r).width) - MAX((x),(r).x_org)) \ #define INTERSECT(x,y,w,h,r) (MAX(0, MIN((x)+(w),(r).x_org+(r).width) - MAX((x),(r).x_org)) \
* MAX(0, MIN((y)+(h),(r).y_org+(r).height) - MAX((y),(r).y_org))) * MAX(0, MIN((y)+(h),(r).y_org+(r).height) - MAX((y),(r).y_org)))
#define LENGTH(X) (sizeof X / sizeof X[0])
#if PANGO_PATCH #if PANGO_PATCH
#define TEXTW(X) (drw_font_getwidth(drw, (X), False) + lrpad) #define TEXTW(X) (drw_font_getwidth(drw, (X), False) + lrpad)
#define TEXTWM(X) (drw_font_getwidth(drw, (X), True) + lrpad) #define TEXTWM(X) (drw_font_getwidth(drw, (X), True) + lrpad)

23
drw.c
View File

@ -430,8 +430,8 @@ drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lp
int int
drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lpad, const char *text, int invert) drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lpad, const char *text, int invert)
{ {
int i, ty, ellipsis_x = 0; int ty, ellipsis_x = 0;
unsigned int tmpw, ew, ellipsis_w = 0, ellipsis_len; unsigned int tmpw, ew, ellipsis_w = 0, ellipsis_len, hash, h0, h1;
XftDraw *d = NULL; XftDraw *d = NULL;
Fnt *usedfont, *curfont, *nextfont; Fnt *usedfont, *curfont, *nextfont;
int utf8strlen, utf8charlen, render = x || y || w || h; int utf8strlen, utf8charlen, render = x || y || w || h;
@ -443,10 +443,8 @@ drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lp
XftResult result; XftResult result;
int charexists = 0, overflow = 0; int charexists = 0, overflow = 0;
/* keep track of a couple codepoints for which we have no match. */ /* keep track of a couple codepoints for which we have no match. */
enum { nomatches_len = 64 }; static unsigned int nomatches[128], ellipsis_width;
static struct { long codepoint[nomatches_len]; unsigned int idx; } nomatches;
const char *ellipsis = "..."; const char *ellipsis = "...";
static unsigned int ellipsis_width = 0;
if (!drw || (render && (!drw->scheme || !w)) || !text || !drw->fonts) if (!drw || (render && (!drw->scheme || !w)) || !text || !drw->fonts)
return 0; return 0;
@ -535,11 +533,14 @@ drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lp
* character must be drawn. */ * character must be drawn. */
charexists = 1; charexists = 1;
for (i = 0; i < nomatches_len; ++i) { hash = (unsigned int)utf8codepoint;
/* avoid calling XftFontMatch if we know we won't find a match */ hash = ((hash >> 16) ^ hash) * 0x21F0AAAD;
if (utf8codepoint == nomatches.codepoint[i]) hash = ((hash >> 15) ^ hash) * 0xD35A2D97;
goto no_match; h0 = ((hash >> 15) ^ hash) % LENGTH(nomatches);
} h1 = (hash >> 17) % LENGTH(nomatches);
/* avoid expensive XftFontMatch call when we know we won't find a match */
if (nomatches[h0] == utf8codepoint || nomatches[h1] == utf8codepoint)
goto no_match;
fccharset = FcCharSetCreate(); fccharset = FcCharSetCreate();
FcCharSetAddChar(fccharset, utf8codepoint); FcCharSetAddChar(fccharset, utf8codepoint);
@ -571,7 +572,7 @@ drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lp
curfont->next = usedfont; curfont->next = usedfont;
} else { } else {
xfont_free(usedfont); xfont_free(usedfont);
nomatches.codepoint[++nomatches.idx % nomatches_len] = utf8codepoint; nomatches[nomatches[h0] ? h1 : h0] = utf8codepoint;
no_match: no_match:
usedfont = drw->fonts; usedfont = drw->fonts;
} }

1
util.h
View File

@ -7,6 +7,7 @@
#define MIN(A, B) ((A) < (B) ? (A) : (B)) #define MIN(A, B) ((A) < (B) ? (A) : (B))
#endif #endif
#define BETWEEN(X, A, B) ((A) <= (X) && (X) <= (B)) #define BETWEEN(X, A, B) ((A) <= (X) && (X) <= (B))
#define LENGTH(X) (sizeof (X) / sizeof (X)[0])
void die(const char *fmt, ...); void die(const char *fmt, ...);
void *ecalloc(size_t nmemb, size_t size); void *ecalloc(size_t nmemb, size_t size);