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+/* PowerPC-specific implementation of profiling support.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.	*/
+
+/* This would be bad.  */
+#ifdef PROF
+#undef PROF
+#endif
+
+#include <sysdep.h>
+
+/* We do profiling as described in the SYSV ELF ABI, _mcount is called
+   with the address of a data word in r0 (that is different for every
+   routine, initialised to 0, and otherwise unused).  The caller has put
+   the address the caller will return to in the usual place on the stack,
+   4(%r1).  _mcount is responsible for ensuring that when it returns no
+   argument-passing registers are disturbed, and that the LR is set back
+   to (what the caller sees as) 4(%r1).
+
+   This is intended so that the following code can be inserted at the
+   front of any routine without changing the routine:
+
+	.data
+	.align	2
+   0:	.long	0
+	.previous
+	mflr	%r0
+	lis	%r11,0b@ha
+	stw	%r0,4(%r1)
+	addi	%r0,%r11,0b@l
+	bl	_mcount
+*/
+
+ENTRY(_mcount)
+	stwu	%r1,-48(%r1)
+/* We need to save the parameter-passing registers.  */
+	stw	%r3, 12(%r1)
+	stw	%r4, 16(%r1)
+	stw	%r5, 20(%r1)
+	stw	%r6, 24(%r1)
+	mflr	%r4
+	lwz	%r3, 52(%r1)
+	mfcr	%r5
+	stw	%r7, 28(%r1)
+	stw	%r8, 32(%r1)
+	stw	%r9, 36(%r1)
+	stw	%r10,40(%r1)
+	stw	%r4, 44(%r1)
+	stw	%r5,  8(%r1)
+	bl	JUMPTARGET(__mcount_internal)
+ /* Restore the registers...  */
+	lwz     %r6,  8(%r1)
+	lwz	%r0, 44(%r1)
+	lwz	%r3, 12(%r1)
+	mtctr	%r0
+	lwz	%r4, 16(%r1)
+	mtcrf	0xff,%r6
+	lwz	%r5, 20(%r1)
+	lwz	%r6, 24(%r1)
+	lwz	%r0, 52(%r1)
+	lwz	%r7, 28(%r1)
+	lwz	%r8, 32(%r1)
+	mtlr	%r0
+	lwz	%r9, 36(%r1)
+	lwz	%r10,40(%r1)
+ /* ...unwind the stack frame, and return to your usual programming.  */
+	addi	%r1,%r1,48
+	bctr
+END(_mcount)