xref: /freebsd-src/contrib/llvm-project/compiler-rt/lib/builtins/arm/sync_synchronize.S (revision 0b57cec536236d46e3dba9bd041533462f33dbb7)
1*0b57cec5SDimitry Andric//===-- sync_synchronize - Implement memory barrier * ----------------------===//
2*0b57cec5SDimitry Andric//
3*0b57cec5SDimitry Andric// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*0b57cec5SDimitry Andric// See https://llvm.org/LICENSE.txt for license information.
5*0b57cec5SDimitry Andric// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*0b57cec5SDimitry Andric//
7*0b57cec5SDimitry Andric//===----------------------------------------------------------------------===//
8*0b57cec5SDimitry Andric
9*0b57cec5SDimitry Andric#include "../assembly.h"
10*0b57cec5SDimitry Andric
11*0b57cec5SDimitry Andric// When compiling a use of the gcc built-in __sync_synchronize() in thumb1 mode
12*0b57cec5SDimitry Andric// the compiler may emit a call to __sync_synchronize.
13*0b57cec5SDimitry Andric// On Darwin the implementation jumps to an OS supplied function named
14*0b57cec5SDimitry Andric// OSMemoryBarrier
15*0b57cec5SDimitry Andric
16*0b57cec5SDimitry Andric	.text
17*0b57cec5SDimitry Andric	.syntax unified
18*0b57cec5SDimitry Andric
19*0b57cec5SDimitry Andric#if __APPLE__
20*0b57cec5SDimitry Andric
21*0b57cec5SDimitry Andric	.p2align 2
22*0b57cec5SDimitry AndricDEFINE_COMPILERRT_PRIVATE_FUNCTION(__sync_synchronize)
23*0b57cec5SDimitry Andric	stmfd	sp!, {r7, lr}
24*0b57cec5SDimitry Andric	add		r7, sp, #0
25*0b57cec5SDimitry Andric	bl		_OSMemoryBarrier
26*0b57cec5SDimitry Andric	ldmfd	sp!, {r7, pc}
27*0b57cec5SDimitry AndricEND_COMPILERRT_FUNCTION(__sync_synchronize)
28*0b57cec5SDimitry Andric
29*0b57cec5SDimitry Andric	// tell linker it can break up file at label boundaries
30*0b57cec5SDimitry Andric	.subsections_via_symbols
31*0b57cec5SDimitry Andric
32*0b57cec5SDimitry Andric#endif
33*0b57cec5SDimitry Andric
34*0b57cec5SDimitry AndricNO_EXEC_STACK_DIRECTIVE
35*0b57cec5SDimitry Andric
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