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-rw-r--r--sysdeps/unix/sysv/linux/arm/atomic-machine.h107
1 files changed, 0 insertions, 107 deletions
diff --git a/sysdeps/unix/sysv/linux/arm/atomic-machine.h b/sysdeps/unix/sysv/linux/arm/atomic-machine.h
deleted file mode 100644
index 5fb516284b..0000000000
--- a/sysdeps/unix/sysv/linux/arm/atomic-machine.h
+++ /dev/null
@@ -1,107 +0,0 @@
-/* Atomic operations. ARM/Linux version.
- Copyright (C) 2002-2017 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 <stdint.h>
-
-/* If the compiler doesn't provide a primitive, we'll use this macro
- to get assistance from the kernel. */
-#ifdef __thumb2__
-# define __arm_assisted_full_barrier() \
- __asm__ __volatile__ \
- ("movw\tip, #0x0fa0\n\t" \
- "movt\tip, #0xffff\n\t" \
- "blx\tip" \
- : : : "ip", "lr", "cc", "memory");
-#else
-# define __arm_assisted_full_barrier() \
- __asm__ __volatile__ \
- ("mov\tip, #0xffff0fff\n\t" \
- "mov\tlr, pc\n\t" \
- "add\tpc, ip, #(0xffff0fa0 - 0xffff0fff)" \
- : : : "ip", "lr", "cc", "memory");
-#endif
-
-/* Atomic compare and exchange. This sequence relies on the kernel to
- provide a compare and exchange operation which is atomic on the
- current architecture, either via cleverness on pre-ARMv6 or via
- ldrex / strex on ARMv6.
-
- It doesn't matter what register is used for a_oldval2, but we must
- specify one to work around GCC PR rtl-optimization/21223. Otherwise
- it may cause a_oldval or a_tmp to be moved to a different register.
-
- We use the union trick rather than simply using __typeof (...) in the
- declarations of A_OLDVAL et al because when NEWVAL or OLDVAL is of the
- form *PTR and PTR has a 'volatile ... *' type, then __typeof (*PTR) has
- a 'volatile ...' type and this triggers -Wvolatile-register-var to
- complain about 'register volatile ... asm ("reg")'. */
-#ifdef __thumb2__
-/* Thumb-2 has ldrex/strex. However it does not have barrier instructions,
- so we still need to use the kernel helper. */
-# define __arm_assisted_compare_and_exchange_val_32_acq(mem, newval, oldval) \
- ({ union { __typeof (oldval) a; uint32_t v; } oldval_arg = { .a = (oldval) };\
- union { __typeof (newval) a; uint32_t v; } newval_arg = { .a = (newval) };\
- register uint32_t a_oldval asm ("r0"); \
- register uint32_t a_newval asm ("r1") = newval_arg.v; \
- register __typeof (mem) a_ptr asm ("r2") = (mem); \
- register uint32_t a_tmp asm ("r3"); \
- register uint32_t a_oldval2 asm ("r4") = oldval_arg.v; \
- __asm__ __volatile__ \
- ("0:\tldr\t%[tmp],[%[ptr]]\n\t" \
- "cmp\t%[tmp], %[old2]\n\t" \
- "bne\t1f\n\t" \
- "mov\t%[old], %[old2]\n\t" \
- "movw\t%[tmp], #0x0fc0\n\t" \
- "movt\t%[tmp], #0xffff\n\t" \
- "blx\t%[tmp]\n\t" \
- "bcc\t0b\n\t" \
- "mov\t%[tmp], %[old2]\n\t" \
- "1:" \
- : [old] "=&r" (a_oldval), [tmp] "=&r" (a_tmp) \
- : [new] "r" (a_newval), [ptr] "r" (a_ptr), \
- [old2] "r" (a_oldval2) \
- : "ip", "lr", "cc", "memory"); \
- (__typeof (oldval)) a_tmp; })
-#else
-# define __arm_assisted_compare_and_exchange_val_32_acq(mem, newval, oldval) \
- ({ union { __typeof (oldval) a; uint32_t v; } oldval_arg = { .a = (oldval) };\
- union { __typeof (newval) a; uint32_t v; } newval_arg = { .a = (newval) };\
- register uint32_t a_oldval asm ("r0"); \
- register uint32_t a_newval asm ("r1") = newval_arg.v; \
- register __typeof (mem) a_ptr asm ("r2") = (mem); \
- register uint32_t a_tmp asm ("r3"); \
- register uint32_t a_oldval2 asm ("r4") = oldval_arg.v; \
- __asm__ __volatile__ \
- ("0:\tldr\t%[tmp],[%[ptr]]\n\t" \
- "cmp\t%[tmp], %[old2]\n\t" \
- "bne\t1f\n\t" \
- "mov\t%[old], %[old2]\n\t" \
- "mov\t%[tmp], #0xffff0fff\n\t" \
- "mov\tlr, pc\n\t" \
- "add\tpc, %[tmp], #(0xffff0fc0 - 0xffff0fff)\n\t" \
- "bcc\t0b\n\t" \
- "mov\t%[tmp], %[old2]\n\t" \
- "1:" \
- : [old] "=&r" (a_oldval), [tmp] "=&r" (a_tmp) \
- : [new] "r" (a_newval), [ptr] "r" (a_ptr), \
- [old2] "r" (a_oldval2) \
- : "ip", "lr", "cc", "memory"); \
- (__typeof (oldval)) a_tmp; })
-#endif
-
-#include <sysdeps/arm/atomic-machine.h>