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diff --git a/sysdeps/s390/s390-32/s390-mcount.S b/sysdeps/s390/s390-32/s390-mcount.S
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+/* S/390-specific implemetation of profiling support.
+   Copyright (C) 2000, 2001 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com)
+
+   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.  */
+
+#include <sysdep.h>
+
+/*
+ * How profiling works on S/390:
+ * On the start of each function _mcount is called with the address of a
+ * data word in %r1 (initialized to 0, used for counting). The compiler
+ * with the option -p generates code of the form:
+ *
+ *         STM    6,15,24(15)
+ *         BRAS   13,.LTN0_0
+ * .LT0_0:
+ * .LC12:  .long  _mcount
+ * .LC13:  .long  .LP0
+ *         .data
+ *         .align 4
+ * .LP0:   .long  0
+ *         .text
+ * # function profiler
+ *         st     14,4(15)
+ *         l      14,.LC12-.LT0_0(13)
+ *         l      1,.LC13-.LT0_0(13)
+ *         basr   14,14
+ *         l      14,4(15)
+ *
+ * The _mcount implementation now has to call __mcount_internal with the
+ * address of .LP0 as first parameter and the return address as second
+ * parameter. &.LP0 was loaded to %r1 and the return address is in %r14.
+ * _mcount may not modify any register.
+ */
+
+	ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(_mcount)
+	ASM_TYPE_DIRECTIVE(C_SYMBOL_NAME(_mcount), @function)
+	.align ALIGNARG(4)
+C_LABEL(_mcount)
+	/* Save the caller-clobbered registers.  */
+	ahi   %r15,-128
+	stm   %r14,%r5,96(%r15)
+	l     %r2,132(%r15)       # callers address  = first parameter
+	la    %r2,0(%r2)          # clear bit 0
+	la    %r3,0(%r14)         # callees address  = second parameter
+
+#ifdef PIC
+	bras  %r14,0f
+	.long _GLOBAL_OFFSET_TABLE_-.
+0:	al    %r14,0(%r14)
+	l     %r14,__mcount_internal@GOT(%r14)
+#else
+	bras  %r14,0f
+	.long __mcount_internal
+0:      l     %r14,0(%r14)
+#endif
+	basr  %r14,%r14
+
+	/*
+	 * Pop the saved registers.  Please note that `mcount' has no
+	 * return value.
+	 */
+	lm    %r14,%r5,96(%r15)
+	ahi   %r15,128
+	br    %r14
+	ASM_SIZE_DIRECTIVE(C_SYMBOL_NAME(_mcount))
+
+#undef mcount
+weak_alias(_mcount, mcount)