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https://github.com/c64scene-ar/llvm-6502.git
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9eb0a09710
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220936 91177308-0d34-0410-b5e6-96231b3b80d8
25 lines
486 B
C++
25 lines
486 B
C++
#include <winbase.h>
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#ifdef MemoryFence
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// WinNT.h seems to define a MemoryFence macro.
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#undef MemoryFence
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#endif
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void llvm::call_once(once_flag &flag, void (*fptr)(void)) {
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while (flag != Done) {
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if (flag == Wait) {
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::Sleep(1);
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continue;
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}
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sys::cas_flag old_val = sys::CompareAndSwap(&flag, Wait, Uninitialized);
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if (old_val == Uninitialized) {
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fptr();
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sys::MemoryFence();
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flag = Done;
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return;
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}
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}
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sys::MemoryFence();
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}
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