Module Name:    src
Committed By:   martin
Date:           Thu Mar 22 17:03:02 UTC 2018

Modified Files:
        src/sys/arch/i386/include [netbsd-8]: profile.h

Log Message:
Pull up following revision(s) (requested by christos in ticket #653):
        sys/arch/i386/include/profile.h: revision 1.36
        sys/arch/i386/include/profile.h: revision 1.37

- prevent optimization from omitting the frame pointer (and re-using it);
  we use it in our inline assembly.
- convert to c a little assembly to make the code more understandable.

use compiler builtins to compute addresses instead %ebp assembly arithmetic.
(from joerg)


To generate a diff of this commit:
cvs rdiff -u -r1.35 -r1.35.2.1 src/sys/arch/i386/include/profile.h

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.

Modified files:

Index: src/sys/arch/i386/include/profile.h
diff -u src/sys/arch/i386/include/profile.h:1.35 src/sys/arch/i386/include/profile.h:1.35.2.1
--- src/sys/arch/i386/include/profile.h:1.35	Wed May 31 01:50:19 2017
+++ src/sys/arch/i386/include/profile.h	Thu Mar 22 17:03:02 2018
@@ -1,4 +1,4 @@
-/*	$NetBSD: profile.h,v 1.35 2017/05/31 01:50:19 christos Exp $	*/
+/*	$NetBSD: profile.h,v 1.35.2.1 2018/03/22 17:03:02 martin Exp $	*/
 
 /*
  * Copyright (c) 1992, 1993
@@ -71,12 +71,11 @@ mcount(void)								\
 	 *								\
 	 * selfpc = pc pushed by mcount call				\
 	 */								\
-	__asm volatile("movl 4(%%ebp),%0" : "=r" (selfpc));		\
+	selfpc = (int)__builtin_return_address(0);			\
 	/*								\
-	 * frompcindex = pc pushed by call into self.			\
+	 * frompcindex = stack frame of caller, assuming frame pointer	\
 	 */								\
-	__asm volatile("movl (%%ebp),%0;movl 4(%0),%0"			\
-	    : "=r" (frompcindex));					\
+	frompcindex = ((int *)__builtin_frame_address(1))[1];		\
 	_mcount((u_long)frompcindex, (u_long)selfpc);			\
 									\
 	__asm volatile("movl %0,%%edx" : : "g" (edx));			\

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