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+/* Machine-specific calling sequence for `mcount' profiling function.  ia64
+   Copyright (C) 2000-2014 Free Software Foundation, Inc.
+     Contributed by David Mosberger <davidm@hpl.hp.com>
+   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 Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* Assembly stub to invoke _mcount().  Compiler generated code calls
+   this stub before executing a function's prologue and without saving
+   any registers.  It is therefore necessary to preserve the input
+   registers as they may contain function arguments.  To work
+   correctly with frame-less functions, it is also necessary to
+   preserve the return pointer (b0 aka rp).
+
+   State upon entering _mcount:
+
+    r8  address of return value structure (used only when called
+	function returns a large structure)
+    r15 static link (used only for nested functions)
+    in0 ar.pfs to restore before returning to the function that
+	called _mcount
+    in1 gp value to restore before returning to the function that
+	called _mcount
+    in2 return address in the function that invoked the caller
+	of _mcount (frompc)
+    in3	address of the global-offset table entry that holds the
+	profile count dword allocated by the compiler; to get
+	the address of this dword, use "ld8 in2=[in2]; this
+	dword can be used in any way by _mcount (including
+	not at all, as is the case with the current implementation)
+    b0	address to return to after _mcount is done
+*/
+
+#include <sysdep.h>
+
+#undef ret
+
+LEAF(_mcount)
+	.prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(4)
+	alloc loc1 = ar.pfs, 4, 4, 3, 0
+	mov loc0 = rp
+	.body
+	mov loc2 = r8	// gcc uses r8 to pass pointer to return structure
+	;;
+	mov loc3 = r15	// gcc uses r15 to pass the static link to nested functions
+	mov out0 = in2
+	mov out1 = rp
+	br.call.sptk.few rp = __mcount
+	;;
+.here:
+{
+	.mii
+	mov gp = in1
+	mov r2 = ip
+	mov ar.pfs = loc1
+}
+	;;
+	adds r2 = _mcount_ret_helper - .here, r2
+	mov b7 = loc0
+	mov rp = in2
+	;;
+	mov r3 = in0
+	mov r8 = loc2
+	mov r15 = loc3
+	mov b6 = r2
+	br.ret.sptk.few b6
+END(_mcount)
+
+LOCAL_LEAF(_mcount_ret_helper)
+	.prologue
+	.altrp b7
+	.save ar.pfs, r3
+	.body
+	alloc r2 = ar.pfs, 0, 0, 8, 0
+	mov ar.pfs = r3
+	br b7
+END(_mcount_ret_helper)
+
+weak_alias (_mcount, mcount)