shithub: riscv

Info  •  Files  •  Log  •  Branches

libdraw: avoid BPSHORT()/BPLONG() expansion, cleanup loadchar(),cachechars()

assigning the expression value to a temporary variable in
BPSHORT() and BPLONG() saves arround 2K of text in rio on
arm and arround 1K on amd64.

loadchar(): use the passed in "h" as the char index instead
of recomputing it from c-f->cache. dont recompute wid.

cachechars(): do cache lookup and find oldest entry in a
single loop pass.

--- a/sys/include/ape/draw.h

+++ b/sys/include/ape/draw.h

@@ -512,10 +512,10 @@

 extern	int	_drawdebug;	/* set to 1 to see errors from flushimage */

 extern	void	_setdrawop(Display*, Drawop);

-#define	BGSHORT(p)		(((p)[0]<<0) | ((p)[1]<<8))

-#define	BGLONG(p)		((BGSHORT(p)<<0) | (BGSHORT(p+2)<<16))

-#define	BPSHORT(p, v)		((p)[0]=(v), (p)[1]=((v)>>8))

-#define	BPLONG(p, v)		(BPSHORT(p, (v)), BPSHORT(p+2, (v)>>16))

+#define	BGSHORT(p)	((p)[0]|((p)[1]<<8))

+#define	BGLONG(p)	((p)[0]|((p)[1]<<8)|((p)[2]<<16)|((p)[3]<<24))

+#define BPSHORT(p,v)	do{ushort _v_=(v);(p)[0]=_v_;(p)[1]=_v_>>8;}while(0)

+#define BPLONG(p,v)	do{ulong _v_=(v);(p)[0]=_v_;(p)[1]=_v_>>8;(p)[2]=_v_>>16;(p)[3]=_v_>>24;}while(0)

 /*

  * Compressed image file parameters and helper routines

--- a/sys/include/draw.h

+++ b/sys/include/draw.h

@@ -505,10 +505,10 @@

 extern	int	_drawdebug;	/* set to 1 to see errors from flushimage */

 extern	void	_setdrawop(Display*, Drawop);

-#define	BGSHORT(p)		(((p)[0]<<0) | ((p)[1]<<8))

-#define	BGLONG(p)		((BGSHORT(p)<<0) | (BGSHORT(p+2)<<16))

-#define	BPSHORT(p, v)		((p)[0]=(v), (p)[1]=((v)>>8))

-#define	BPLONG(p, v)		(BPSHORT(p, (v)), BPSHORT(p+2, (v)>>16))

+#define	BGSHORT(p)	((p)[0]|((p)[1]<<8))

+#define	BGLONG(p)	((p)[0]|((p)[1]<<8)|((p)[2]<<16)|((p)[3]<<24))

+#define BPSHORT(p,v)	do{ushort _v_=(v);(p)[0]=_v_;(p)[1]=_v_>>8;}while(0)

+#define BPLONG(p,v)	do{ulong _v_=(v);(p)[0]=_v_;(p)[1]=_v_>>8;(p)[2]=_v_>>16;(p)[3]=_v_>>24;}while(0)

 /*

  * Compressed image file parameters and helper routines

--- a/sys/src/libdraw/font.c

+++ b/sys/src/libdraw/font.c

@@ -10,7 +10,7 @@

 int

 cachechars(Font *f, char **ss, Rune **rr, ushort *cp, int max, int *wp, char **subfontname)

 {

-	int i, j, th, sh, h, w, rw, wid, nc;

+	int i, j, h, w, rw, wid, nc;

 	char *sp;

 	Rune r, *rp, vr;

 	ulong a;

@@ -41,32 +41,24 @@

 			rw = 1;

 		}

-		sh = (17 * (uint)r) & (f->ncache-NFLOOK-1);

-		c = &f->cache[sh];

+		a = ~0;

+		h = (17 * (uint)r) & (f->ncache-NFLOOK-1);

+		c = &f->cache[h];

+		tc = c;

 		ec = c+NFLOOK;

-		h = sh;

 		while(c < ec){

 			if(c->value==r && c->age)

 				goto Found;

+			if(c->age < a){

+				a = c->age;

+				tc = c;

+			}

 			c++;

 			h++;

 		}

-	

-		/*

-		 * Not found; toss out oldest entry

-		 */

-		a = ~0;

-		th = sh;

-		tc = &f->cache[th];

-		while(tc < ec){

-			if(tc->age < a){

-				a = tc->age;

-				h = th;

-				c = tc;

-			}

-			tc++;

-			th++;

-		}

+		/* Not found; use oldest entry */

+		c = tc;

+		h = tc - f->cache;

 		if(a && (f->age-a)<500){	/* kicking out too recent; resize */

 			nc = 2*(f->ncache-NFLOOK) + NFLOOK;

@@ -287,8 +279,6 @@

 		/* c is still valid as didn't reallocate f->cache */

 	}

 	c->value = r;

-	top = fi->top + (f->ascent-subf->f->ascent);

-	bottom = fi->bottom + (f->ascent-subf->f->ascent);

 	c->width = fi->width;

 	c->x = h*f->width;

 	c->left = fi->left;

@@ -297,13 +287,15 @@

 	b = bufimage(f->display, 37);

 	if(b == nil)

 		return 0;

+	top = fi->top + (f->ascent-subf->f->ascent);

+	bottom = fi->bottom + (f->ascent-subf->f->ascent);

 	b[0] = 'l';

 	BPLONG(b+1, f->cacheimage->id);

 	BPLONG(b+5, subf->f->bits->id);

-	BPSHORT(b+9, c-f->cache);

+	BPSHORT(b+9, h);

 	BPLONG(b+11, c->x);

 	BPLONG(b+15, top);

-	BPLONG(b+19, c->x+((fi+1)->x-fi->x));

+	BPLONG(b+19, c->x+wid);

 	BPLONG(b+23, bottom);

 	BPLONG(b+27, fi->x);

 	BPLONG(b+31, fi->top);