llvm-project/compiler-rt/lib/builtins/arm/sync_synchronize.S

//===-- sync_synchronize - Implement memory barrier * ----------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#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

NO_EXEC_STACK_DIRECTIVE
add __sync_synchronize. Needed by compiler when emitting thumb1 with -fno-builtin llvm-svn: 95132 2010-02-03 05:34:04 +08:00			`//===-- sync_synchronize - Implement memory barrier * ----------------------===//`
			`//`
Update more file headers across all of the LLVM projects in the monorepo to reflect the new license. These used slightly different spellings that defeated my regular expressions. We understand that people may be surprised that we're moving the header entirely to discuss the new license. We checked this carefully with the Foundation's lawyer and we believe this is the correct approach. Essentially, all code in the project is now made available by the LLVM project under our new license, so you will see that the license headers include that license only. Some of our contributors have contributed code under our old license, and accordingly, we have retained a copy of our old license notice in the top-level files in each project and repository. llvm-svn: 351648 2019-01-19 18:56:40 +08:00			`// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.`
			`// See https://llvm.org/LICENSE.txt for license information.`
			`// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception`
add __sync_synchronize. Needed by compiler when emitting thumb1 with -fno-builtin llvm-svn: 95132 2010-02-03 05:34:04 +08:00			`//`
			`//===----------------------------------------------------------------------===//`

			`#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__`

[CompilerRT] use .p2align, .balign instead of .align The .align statements in ARM assembly routines is actually meant to be a power of 2 alignment (e.g. .align 2 == 4 byte alignment, not 2). Switch to using .p2align. .p2align is guaranteed to be a power-of-two alignment always and much more explicit. The .align in the case of x86_64 is byte alignment, use .balign instead of .align. llvm-svn: 208578 2014-05-12 23:23:37 +08:00			`.p2align 2`
add __sync_synchronize. Needed by compiler when emitting thumb1 with -fno-builtin llvm-svn: 95132 2010-02-03 05:34:04 +08:00			`DEFINE_COMPILERRT_PRIVATE_FUNCTION(__sync_synchronize)`
			`stmfd sp!, {r7, lr}`
			`add r7, sp, #0`
			`bl _OSMemoryBarrier`
			`ldmfd sp!, {r7, pc}`
Mechanically add end-of-function markers. llvm-svn: 200005 2014-01-24 22:33:42 +08:00			`END_COMPILERRT_FUNCTION(__sync_synchronize)`
add __sync_synchronize. Needed by compiler when emitting thumb1 with -fno-builtin llvm-svn: 95132 2010-02-03 05:34:04 +08:00
			`// tell linker it can break up file at label boundaries`
			`.subsections_via_symbols`

			`#endif`
builtins: tag with noexecstack These routines do not require executable stacks. However, by default ELFish linkers may assume an executable stack on GNUish environments (and some non-GNU ones too!). The GNU extension to add a note to indicate a non-executable stack is honoured by these environments to mark the stack as non-executable (the compiler normally emits this directive on appropriate targets whenever possible). This allows normal builds from getting executable stacks due to linking to the compiler rt builtins. llvm-svn: 273500 2016-06-23 06:09:42 +08:00
			`NO_EXEC_STACK_DIRECTIVE`