auto import from //depot/cupcake/@135843

libstdc++/src/one_time_construction.cpp

@@ -1,50 +0,0 @@
-/*
- * one_time_construction.cpp
- *
- * Copyright 2006 The Android Open Source Project
- *
- * This file contains C++ ABI support functions for one time
- * constructors as defined in the "Run-time ABI for the ARM Architecture"
- * section 4.4.2
- */
-
-#include <stddef.h>
-#include <sys/atomics.h>
-
-extern "C" int __futex_wait(volatile void *ftx, int val, const struct timespec *timeout);
-extern "C" int __futex_wake(volatile void *ftx, int count);
-
-
-extern "C" int __cxa_guard_acquire(int volatile * gv)
-{
-    // 0 -> 2, return 1
-    // 2 -> 6, wait and return 0
-    // 6 untouched, wait and return 0
-    // 1 untouched, return 0
-retry:
-    if (__atomic_cmpxchg(0, 0x2, gv) == 0)
-        return 1;
-
-    __atomic_cmpxchg(0x2, 0x6, gv); // Indicate there is a waiter
-    __futex_wait(gv, 0x6, NULL);
-    if(*gv != 1) // __cxa_guard_abort was called, let every thread try since there is no return code for this condition
-        goto retry;
-    return 0;
-}
-
-extern "C" void __cxa_guard_release(int volatile * gv)
-{
-    // 2 -> 1
-    // 6 -> 1, and wake
-    if (__atomic_cmpxchg(0x2, 0x1, gv) == 0)
-        return;
-
-    *gv = 0x1;
-    __futex_wake(gv, 0x7fffffff);
-}
-
-extern "C" void __cxa_guard_abort(int volatile * gv)
-{
-    *gv = 0;
-    __futex_wake(gv, 0x7fffffff);
-}