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Diffstat (limited to 'lib/builtins/arm/sync_synchronize.S')
| -rw-r--r-- | lib/builtins/arm/sync_synchronize.S | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/lib/builtins/arm/sync_synchronize.S b/lib/builtins/arm/sync_synchronize.S new file mode 100644 index 0000000000000..178f24534c714 --- /dev/null +++ b/lib/builtins/arm/sync_synchronize.S @@ -0,0 +1,35 @@ +//===-- sync_synchronize - Implement memory barrier * ----------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is dual licensed under the MIT and the University of Illinois Open +// Source Licenses. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "../assembly.h" + +// +// When compiling a use of the gcc built-in __sync_synchronize() in thumb1 mode +// the compiler may emit a call to __sync_synchronize. +// On Darwin the implementation jumps to an OS supplied function named +// OSMemoryBarrier +// + + .text + .syntax unified + +#if __APPLE__ + + .p2align 2 +DEFINE_COMPILERRT_PRIVATE_FUNCTION(__sync_synchronize) + stmfd sp!, {r7, lr} + add r7, sp, #0 + bl _OSMemoryBarrier + ldmfd sp!, {r7, pc} +END_COMPILERRT_FUNCTION(__sync_synchronize) + + // tell linker it can break up file at label boundaries + .subsections_via_symbols + +#endif |