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-rw-r--r--sysdeps/arm/arm-mcount.S129
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+/* Implementation of profiling support. ARM EABI version.
+ Copyright (C) 2008-2014 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/>. */
+
+/* Don't call mcount when calling mcount... */
+#undef PROF
+
+#include <sysdep.h>
+
+#undef mcount
+
+#ifdef __thumb2__
+ .thumb
+#endif
+ .syntax unified
+
+
+/* Use an assembly stub with a special ABI. The calling lr has been
+ pushed to the stack (which will be misaligned). We should preserve
+ all registers except ip and pop a word off the stack.
+
+ NOTE: This assumes mcount_internal does not clobber any non-core
+ (coprocessor) registers. Currently this is true, but may require
+ additional attention in the future.
+
+ The calling sequence looks something like:
+func:
+ push {lr}
+ bl __gnu_mcount_nc
+ <function body>
+*/
+
+ENTRY(__gnu_mcount_nc)
+ push {r0, r1, r2, r3, lr}
+ cfi_adjust_cfa_offset (20)
+ cfi_rel_offset (r0, 0)
+ cfi_rel_offset (r1, 4)
+ cfi_rel_offset (r2, 8)
+ cfi_rel_offset (r3, 12)
+ cfi_rel_offset (lr, 16)
+ bic r1, lr, #1
+ ldr r0, [sp, #20]
+ bl __mcount_internal
+ pop {r0, r1, r2, r3, ip, lr}
+ cfi_adjust_cfa_offset (-24)
+ cfi_restore (r0)
+ cfi_restore (r1)
+ cfi_restore (r2)
+ cfi_restore (r3)
+ cfi_register (lr, ip)
+ bx ip
+END(__gnu_mcount_nc)
+
+
+#include <gcc-compat.h>
+#include <shlib-compat.h>
+
+/* The new __gnu_mcount_nc entry point was introduced in 4.4, so the
+ static library needs the old one only to support older compilers.
+ Even in a configuration that only cares about newer compilers, the
+ shared library might need it only for strict ABI compatibility. */
+
+#if GCC_COMPAT (4, 3) || SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_19)
+
+/* Provide old mcount for backwards compatibility. This requires
+ code be compiled with APCS frame pointers. */
+
+ENTRY(__mcount_arm_compat)
+ push {r0, r1, r2, r3, fp, lr}
+ cfi_adjust_cfa_offset (24)
+ cfi_rel_offset (r0, 0)
+ cfi_rel_offset (r1, 4)
+ cfi_rel_offset (r2, 8)
+ cfi_rel_offset (r3, 12)
+ cfi_rel_offset (fp, 16)
+ cfi_rel_offset (lr, 20)
+ movs r0, fp
+ ittt ne
+ sfi_breg r0, \
+ ldrne r0, [\B, #-4]
+ movsne r1, lr
+ blne __mcount_internal
+# if defined (__ARM_ARCH_4T__) && defined (__THUMB_INTERWORK__)
+ pop {r0, r1, r2, r3, fp, lr}
+ cfi_adjust_cfa_offset (-24)
+ cfi_restore (r0)
+ cfi_restore (r1)
+ cfi_restore (r2)
+ cfi_restore (r3)
+ cfi_restore (fp)
+ cfi_restore (lr)
+ bx lr
+# else
+ pop {r0, r1, r2, r3, fp, pc}
+# endif
+END(__mcount_arm_compat)
+
+#endif
+
+#if GCC_COMPAT (4, 3)
+
+strong_alias (__mcount_arm_compat, _mcount)
+
+/* 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, mcount)
+
+#elif SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_19)
+
+compat_symbol (libc, __mcount_arm_compat, _mcount, GLIBC_2_0)
+
+strong_alias (__mcount_arm_compat, __mcount_arm_compat_1)
+compat_symbol (libc, __mcount_arm_compat_1, mcount, GLIBC_2_0)
+
+#endif