This is the mail archive of the
libc-ports@sources.redhat.com
mailing list for the libc-ports project.
[PATCH] [AArch64] Provide symbol versions for mcount and _mcount.
- From: Marcus Shawcroft <marcus dot shawcroft at linaro dot org>
- To: libc-ports at sourceware dot org
- Cc: Marcus Shawcroft <marcus dot shawcroft at linaro dot org>
- Date: Thu, 25 Jul 2013 09:08:34 +0100
- Subject: [PATCH] [AArch64] Provide symbol versions for mcount and _mcount.
Hi,
This patch fixes the symbol versions associated with mcount and _mcount in the AArch64 port.
The initial AArch64 port in 2.17 omitted this interface. A patch earlier this year here
http://sourceware.org/ml/libc-ports/2013-05/msg00087.html introduced
the symbols but introduced them with default 2_17 versions instead of 2_18.
This patch versions them correctly.
I'd appreciate a review of this patch.
Cheers
/Marcus
2013-07-25 Marcus Shawcroft <marcus.shawcroft@linaro.org>
* sysdeps/aarch64/Versions: New file.
* sysdeps/aarch64/machine-gmon.h: New file.
* sysdeps/aarch64/mcount.c: New file.
* sysdeps/unix/sysv/linux/aarch64/nptl/libc.abilist (mcount): Add.
(_mcount): Likewise.
---
ports/ChangeLog.aarch64 | 8 ++++
ports/sysdeps/aarch64/Versions | 5 +++
ports/sysdeps/aarch64/machine-gmon.h | 43 ++++++++++++++++++++++
ports/sysdeps/aarch64/mcount.c | 39 ++++++++++++++++++++
.../unix/sysv/linux/aarch64/nptl/libc.abilist | 2 +
5 files changed, 97 insertions(+)
create mode 100644 ports/sysdeps/aarch64/Versions
create mode 100644 ports/sysdeps/aarch64/machine-gmon.h
create mode 100644 ports/sysdeps/aarch64/mcount.c
diff --git a/ports/ChangeLog.aarch64 b/ports/ChangeLog.aarch64
index 3f26cb7..ee7f831 100644
--- a/ports/ChangeLog.aarch64
+++ b/ports/ChangeLog.aarch64
@@ -1,3 +1,11 @@
+2013-07-25 Marcus Shawcroft <marcus.shawcroft@linaro.org>
+
+ * sysdeps/aarch64/Versions: New file.
+ * sysdeps/aarch64/machine-gmon.h: New file.
+ * sysdeps/aarch64/mcount.c: New file.
+ * sysdeps/unix/sysv/linux/aarch64/nptl/libc.abilist (mcount): Add.
+ (_mcount): Likewise.
+
2013-07-12 Marcus Shawcroft <marcus.shawcroft@linaro.org>
* sysdeps/aarch64/Makefile (CFLAGS-backtrace.c): Define.
diff --git a/ports/sysdeps/aarch64/Versions b/ports/sysdeps/aarch64/Versions
new file mode 100644
index 0000000..29bbc86
--- /dev/null
+++ b/ports/sysdeps/aarch64/Versions
@@ -0,0 +1,5 @@
+libc {
+ GLIBC_2.18 {
+ mcount; _mcount;
+ }
+}
diff --git a/ports/sysdeps/aarch64/machine-gmon.h b/ports/sysdeps/aarch64/machine-gmon.h
new file mode 100644
index 0000000..815f7bb
--- /dev/null
+++ b/ports/sysdeps/aarch64/machine-gmon.h
@@ -0,0 +1,43 @@
+/* Machine-dependent definitions for profiling support. Generic GCC 2 version.
+ Copyright (C) 1996-2013 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 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/>. */
+
+/* GCC version 2 gives us a perfect magical function to get
+ just the information we need:
+ void *__builtin_return_address (unsigned int N)
+ returns the return address of the frame N frames up. */
+
+/* Be warned that GCC cannot usefully compile __builtin_return_address(N)
+ for N != 0 on all machines. In this case, you may have to write
+ your own version of _mcount(). */
+
+#if __GNUC__ < 2
+ #error "This file uses __builtin_return_address, a GCC 2 extension."
+#endif
+
+#include <sysdep.h>
+
+static void mcount_internal (u_long frompc, u_long selfpc);
+
+#define _MCOUNT_DECL(frompc, selfpc) \
+static inline void mcount_internal (u_long frompc, u_long selfpc)
+
+#define MCOUNT \
+void __mcount (void) \
+{ \
+ mcount_internal ((u_long) RETURN_ADDRESS (1), (u_long) RETURN_ADDRESS (0)); \
+}
diff --git a/ports/sysdeps/aarch64/mcount.c b/ports/sysdeps/aarch64/mcount.c
new file mode 100644
index 0000000..8871a4f
--- /dev/null
+++ b/ports/sysdeps/aarch64/mcount.c
@@ -0,0 +1,39 @@
+/* Copyright (C) 2013 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 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/>. */
+
+#include <shlib-compat.h>
+
+#include <gmon/mcount.c>
+
+/* We forgot to add _mcount and mcount in glibc 2.17. We added them in 2.18
+ therefore we want them to be added with version GLIBC_2_18. However, setting
+ then version is not straight forward because generic Version files include
+ an earlier 2.xx version for each of these symbols and the linker uses the
+ first version it sees. */
+
+#if SHLIB_COMPAT (libc, GLIBC_2_17, GLIBC_2_18)
+/* The canonical name for the function is `_mcount' in both C and asm,
+ but some old asm code might assume it's `mcount'. */
+weak_alias (__mcount, __weak_mcount)
+versioned_symbol (libc, __weak_mcount, mcount, GLIBC_2_18);
+
+versioned_symbol (libc, __mcount, _mcount, GLIBC_2_18);
+#else
+strong_alias (__mcount, _mcount);
+weak_alias (__mcount, mcount)
+#endif
diff --git a/ports/sysdeps/unix/sysv/linux/aarch64/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/aarch64/nptl/libc.abilist
index b04a761..b99dc36 100644
--- a/ports/sysdeps/unix/sysv/linux/aarch64/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/aarch64/nptl/libc.abilist
@@ -2080,3 +2080,5 @@ GLIBC_2.17
GLIBC_2.18
GLIBC_2.18 A
__cxa_thread_atexit_impl F
+ _mcount F
+ mcount F
--
1.8.1.2