summaryrefslogtreecommitdiff
path: root/sysdeps/ia64/_mcount.S
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/ia64/_mcount.S')
-rw-r--r--sysdeps/ia64/_mcount.S91
1 files changed, 91 insertions, 0 deletions
diff --git a/sysdeps/ia64/_mcount.S b/sysdeps/ia64/_mcount.S
new file mode 100644
index 0000000000..e009833e4a
--- /dev/null
+++ b/sysdeps/ia64/_mcount.S
@@ -0,0 +1,91 @@
+/* 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)