590e85b575
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
39 lines
971 B
ArmAsm
39 lines
971 B
ArmAsm
//===-- sync_synchronize - Implement memory barrier * ----------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is dual licensed under the MIT and the University of Illinois Open
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// Source Licenses. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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#include "../assembly.h"
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//
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// When compiling a use of the gcc built-in __sync_synchronize() in thumb1 mode
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// the compiler may emit a call to __sync_synchronize.
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// On Darwin the implementation jumps to an OS supplied function named
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// OSMemoryBarrier
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//
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.text
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.syntax unified
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#if __APPLE__
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.p2align 2
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DEFINE_COMPILERRT_PRIVATE_FUNCTION(__sync_synchronize)
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stmfd sp!, {r7, lr}
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add r7, sp, #0
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bl _OSMemoryBarrier
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ldmfd sp!, {r7, pc}
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END_COMPILERRT_FUNCTION(__sync_synchronize)
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// tell linker it can break up file at label boundaries
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.subsections_via_symbols
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#endif
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NO_EXEC_STACK_DIRECTIVE
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