diff options
| author |   deraadt <deraadt@openbsd.org> | 1996-06-18 10:07:41 +0000 |
|---|---|---|
| committer | deraadt <deraadt@openbsd.org> | 1996-06-18 10:07:41 +0000 |
| commit | 64d71990389d0c49a0f7b6d7ebeca8978261a32c (patch) | |
| tree | 4f3dc2367b157c19d82c536a4f311dcc8a1dc28b | |
| parent | update id (diff) | |
| download | wireguard-openbsd-64d71990389d0c49a0f7b6d7ebeca8978261a32c.tar.xz wireguard-openbsd-64d71990389d0c49a0f7b6d7ebeca8978261a32c.zip | |
use p->hashfraction when doing non-time-critical calculations, rather than
using HASHFRACTION directly. in time-critical calculations, if HASHFRACTION
is a power of two, check that p->hashfraction == HASHFRACTION and if so do
the calculation with the compiled-in value so that the compiler can optimize
out (potentially) expensive divisions. if p->hashfraction != HASHFRACTION,
actually do the division. This has the result that on machines with slow
division, the division can be optimized out of the common case, but that
if HASHFRACTION changes from the compiled-in value (for whatever reason),
profiling will still work. Changes suggested by Chris Torek.
| -rw-r--r-- | lib/libc/gmon/gmon.c | 6 | ||||
| -rw-r--r-- | lib/libc/gmon/mcount.c | 23 |
2 files changed, 18 insertions, 11 deletions
diff --git a/lib/libc/gmon/gmon.c b/lib/libc/gmon/gmon.c index 45b14fd5497..cc7dedf252a 100644 --- a/lib/libc/gmon/gmon.c +++ b/lib/libc/gmon/gmon.c @@ -1,4 +1,4 @@ -/* $NetBSD: gmon.c,v 1.5 1995/11/21 22:23:47 jtc Exp $ */ +/* $NetBSD: gmon.c,v 1.5.4.1 1996/06/12 04:20:16 cgd Exp $ */ /*- * Copyright (c) 1983, 1992, 1993 @@ -37,7 +37,7 @@ #if 0 static char sccsid[] = "@(#)gmon.c 8.1 (Berkeley) 6/4/93"; #else -static char rcsid[] = "$NetBSD: gmon.c,v 1.5 1995/11/21 22:23:47 jtc Exp $"; +static char rcsid[] = "$NetBSD: gmon.c,v 1.5.4.1 1996/06/12 04:20:16 cgd Exp $"; #endif #endif @@ -83,7 +83,7 @@ monstartup(lowpc, highpc) p->textsize = p->highpc - p->lowpc; p->kcountsize = p->textsize / HISTFRACTION; p->hashfraction = HASHFRACTION; - p->fromssize = p->textsize / HASHFRACTION; + p->fromssize = p->textsize / p->hashfraction; p->tolimit = p->textsize * ARCDENSITY / 100; if (p->tolimit < MINARCS) p->tolimit = MINARCS; diff --git a/lib/libc/gmon/mcount.c b/lib/libc/gmon/mcount.c index fb8f1ac3f2b..f6c00a53855 100644 --- a/lib/libc/gmon/mcount.c +++ b/lib/libc/gmon/mcount.c @@ -1,4 +1,4 @@ -/* $NetBSD: mcount.c,v 1.3 1995/02/27 12:54:42 cgd Exp $ */ +/* $NetBSD: mcount.c,v 1.3.6.2 1996/06/12 04:20:17 cgd Exp $ */ /*- * Copyright (c) 1983, 1992, 1993 @@ -33,11 +33,11 @@ * SUCH DAMAGE. */ -#if !defined(lint) && !defined(KERNEL) && defined(LIBC_SCCS) +#if !defined(lint) && !defined(_KERNEL) && defined(LIBC_SCCS) #if 0 static char sccsid[] = "@(#)mcount.c 8.1 (Berkeley) 6/4/93"; #else -static char rcsid[] = "$NetBSD: mcount.c,v 1.3 1995/02/27 12:54:42 cgd Exp $"; +static char rcsid[] = "$NetBSD: mcount.c,v 1.3.6.2 1996/06/12 04:20:17 cgd Exp $"; #endif #endif @@ -66,7 +66,7 @@ _MCOUNT_DECL(frompc, selfpc) /* _mcount; may be static, inline, etc */ register struct tostruct *top, *prevtop; register struct gmonparam *p; register long toindex; -#ifdef KERNEL +#ifdef _KERNEL register int s; #endif @@ -77,7 +77,7 @@ _MCOUNT_DECL(frompc, selfpc) /* _mcount; may be static, inline, etc */ */ if (p->state != GMON_PROF_ON) return; -#ifdef KERNEL +#ifdef _KERNEL MCOUNT_ENTER; #else p->state = GMON_PROF_BUSY; @@ -91,7 +91,14 @@ _MCOUNT_DECL(frompc, selfpc) /* _mcount; may be static, inline, etc */ if (frompc > p->textsize) goto done; - frompcindex = &p->froms[frompc / (p->hashfraction * sizeof(*p->froms))]; +#if (HASHFRACTION & (HASHFRACTION - 1)) == 0 + if (p->hashfraction == HASHFRACTION) + frompcindex = + &p->froms[frompc / (HASHFRACTION * sizeof(*p->froms))]; + else +#endif + frompcindex = + &p->froms[frompc / (p->hashfraction * sizeof(*p->froms))]; toindex = *frompcindex; if (toindex == 0) { /* @@ -163,7 +170,7 @@ _MCOUNT_DECL(frompc, selfpc) /* _mcount; may be static, inline, etc */ } done: -#ifdef KERNEL +#ifdef _KERNEL MCOUNT_EXIT; #else p->state = GMON_PROF_ON; @@ -171,7 +178,7 @@ done: return; overflow: p->state = GMON_PROF_ERROR; -#ifdef KERNEL +#ifdef _KERNEL MCOUNT_EXIT; #endif return; |