diff options
Diffstat (limited to 'sysdeps/arm/arm-mcount.S')
-rw-r--r-- | sysdeps/arm/arm-mcount.S | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/sysdeps/arm/arm-mcount.S b/sysdeps/arm/arm-mcount.S new file mode 100644 index 0000000..7e433c6 --- /dev/null +++ b/sysdeps/arm/arm-mcount.S @@ -0,0 +1,129 @@ +/* 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 |