initial import of NetBSD tree

1 files changed, 180 insertions, 0 deletions

diff --git a/sys/lib/libkern/mcount.c b/sys/lib/libkern/mcount.c
new file mode 100644
index 00000000000..f0aee538c3b
--- /dev/null
+++ b/sys/lib/libkern/mcount.c
@@ -0,0 +1,180 @@
+/*	$NetBSD: mcount.c,v 1.3 1995/03/28 20:01:02 jtc Exp $	*/
+
+/*-
+ * Copyright (c) 1983, 1992, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if !defined(lint) && !defined(_KERNEL) && defined(LIBC_SCCS)
+static char sccsid[] = "@(#)mcount.c	8.1 (Berkeley) 6/4/93";
+#endif
+
+#include <sys/param.h>
+#include <sys/gmon.h>
+
+/*
+ * mcount is called on entry to each function compiled with the profiling
+ * switch set.  _mcount(), which is declared in a machine-dependent way
+ * with _MCOUNT_DECL, does the actual work and is either inlined into a
+ * C routine or called by an assembly stub.  In any case, this magic is
+ * taken care of by the MCOUNT definition in <machine/profile.h>.
+ *
+ * _mcount updates data structures that represent traversals of the
+ * program's call graph edges.  frompc and selfpc are the return
+ * address and function address that represents the given call graph edge.
+ * 
+ * Note: the original BSD code used the same variable (frompcindex) for
+ * both frompcindex and frompc.  Any reasonable, modern compiler will
+ * perform this optimization.
+ */
+_MCOUNT_DECL(frompc, selfpc)	/* _mcount; may be static, inline, etc */
+	register u_long frompc, selfpc;
+{
+	register u_short *frompcindex;
+	register struct tostruct *top, *prevtop;
+	register struct gmonparam *p;
+	register long toindex;
+#ifdef _KERNEL
+	register int s;
+#endif
+
+	p = &_gmonparam;
+	/*
+	 * check that we are profiling
+	 * and that we aren't recursively invoked.
+	 */
+	if (p->state != GMON_PROF_ON)
+		return;
+#ifdef _KERNEL
+	MCOUNT_ENTER;
+#else
+	p->state = GMON_PROF_BUSY;
+#endif
+	/*
+	 * check that frompcindex is a reasonable pc value.
+	 * for example:	signal catchers get called from the stack,
+	 *		not from text space.  too bad.
+	 */
+	frompc -= p->lowpc;
+	if (frompc > p->textsize)
+		goto done;
+
+	frompcindex = &p->froms[frompc / (p->hashfraction * sizeof(*p->froms))];
+	toindex = *frompcindex;
+	if (toindex == 0) {
+		/*
+		 *	first time traversing this arc
+		 */
+		toindex = ++p->tos[0].link;
+		if (toindex >= p->tolimit)
+			/* halt further profiling */
+			goto overflow;
+
+		*frompcindex = toindex;
+		top = &p->tos[toindex];
+		top->selfpc = selfpc;
+		top->count = 1;
+		top->link = 0;
+		goto done;
+	}
+	top = &p->tos[toindex];
+	if (top->selfpc == selfpc) {
+		/*
+		 * arc at front of chain; usual case.
+		 */
+		top->count++;
+		goto done;
+	}
+	/*
+	 * have to go looking down chain for it.
+	 * top points to what we are looking at,
+	 * prevtop points to previous top.
+	 * we know it is not at the head of the chain.
+	 */
+	for (; /* goto done */; ) {
+		if (top->link == 0) {
+			/*
+			 * top is end of the chain and none of the chain
+			 * had top->selfpc == selfpc.
+			 * so we allocate a new tostruct
+			 * and link it to the head of the chain.
+			 */
+			toindex = ++p->tos[0].link;
+			if (toindex >= p->tolimit)
+				goto overflow;
+
+			top = &p->tos[toindex];
+			top->selfpc = selfpc;
+			top->count = 1;
+			top->link = *frompcindex;
+			*frompcindex = toindex;
+			goto done;
+		}
+		/*
+		 * otherwise, check the next arc on the chain.
+		 */
+		prevtop = top;
+		top = &p->tos[top->link];
+		if (top->selfpc == selfpc) {
+			/*
+			 * there it is.
+			 * increment its count
+			 * move it to the head of the chain.
+			 */
+			top->count++;
+			toindex = prevtop->link;
+			prevtop->link = top->link;
+			top->link = *frompcindex;
+			*frompcindex = toindex;
+			goto done;
+		}
+		
+	}
+done:
+#ifdef _KERNEL
+	MCOUNT_EXIT;
+#else
+	p->state = GMON_PROF_ON;
+#endif
+	return;
+overflow:
+	p->state = GMON_PROF_ERROR;
+#ifdef _KERNEL
+	MCOUNT_EXIT;
+#endif
+	return;
+}
+
+/*
+ * Actual definition of mcount function.  Defined in <machine/profile.h>,
+ * which is included by <sys/gmon.h>.
+ */
+MCOUNT