From 294010b562c9846bb2bc4ee9c63ff78adc7c1f4f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lisandro=20Dami=C3=A1n=20Nicanor=20P=C3=A9rez=20Meyer?=
 <perezmeyer@gmail.com>
Date: Sat, 15 Mar 2014 15:40:49 -0300
Subject: [PATCH] Add qatomic support for AArch64 (aka arm64).

Patch by Mark Salter <msalter@redhat.com>
licensed under BSD:

<https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=735488#195>

This patch is known to not be the most correct way
to implement them, as it seems to be possible to do it in a faster way,
but should work non the less until we can provide something better.

Change-Id: Ib392b27dc54691fd4c2ea9896240ad71fb8128cc
---
 src/corelib/arch/aarch64/arch.pri            |   4 +
 src/corelib/arch/aarch64/qatomic_aarch64.cpp |  70 ++++++
 src/corelib/arch/arch.pri                    |   4 +-
 src/corelib/arch/qatomic_aarch64.h           | 335 +++++++++++++++++++++++++++
 src/corelib/arch/qatomic_arch.h              |   2 +
 5 files changed, 414 insertions(+), 1 deletion(-)
 create mode 100644 src/corelib/arch/aarch64/arch.pri
 create mode 100644 src/corelib/arch/aarch64/qatomic_aarch64.cpp
 create mode 100644 src/corelib/arch/qatomic_aarch64.h

diff --git a/src/corelib/arch/aarch64/arch.pri b/src/corelib/arch/aarch64/arch.pri
new file mode 100644
index 0000000..63523d9
--- /dev/null
+++ b/src/corelib/arch/aarch64/arch.pri
@@ -0,0 +1,4 @@
+#
+# AArch64 architecture
+#
+SOURCES += $$QT_ARCH_CPP/qatomic_aarch64.cpp
diff --git a/src/corelib/arch/aarch64/qatomic_aarch64.cpp b/src/corelib/arch/aarch64/qatomic_aarch64.cpp
new file mode 100644
index 0000000..fc851b9
--- /dev/null
+++ b/src/corelib/arch/aarch64/qatomic_aarch64.cpp
@@ -0,0 +1,70 @@
+/****************************************************************************
+**
+** Copyright (C) 2012, 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtCore/qglobal.h>
+
+#include <unistd.h>
+#ifdef _POSIX_PRIORITY_SCHEDULING
+# include <sched.h>
+#endif
+#include <time.h>
+
+QT_BEGIN_NAMESPACE
+
+QT_USE_NAMESPACE
+
+Q_CORE_EXPORT void qt_atomic_yield(int *count)
+{
+#ifdef _POSIX_PRIORITY_SCHEDULING
+    if ((*count)++ < 50) {
+        sched_yield();
+    } else
+#endif
+    {
+        struct timespec tm;
+        tm.tv_sec = 0;
+        tm.tv_nsec = 2000001;
+        nanosleep(&tm, NULL);
+        *count = 0;
+    }
+}
+
+QT_END_NAMESPACE
diff --git a/src/corelib/arch/arch.pri b/src/corelib/arch/arch.pri
index cd23e5e..f50fca7 100644
--- a/src/corelib/arch/arch.pri
+++ b/src/corelib/arch/arch.pri
@@ -31,7 +31,9 @@ integrity:HEADERS += arch/qatomic_integrity.h
                        arch/qatomic_s390.h \
                        arch/qatomic_x86_64.h \
                        arch/qatomic_sh.h \
-                       arch/qatomic_sh4a.h
+                       arch/qatomic_sh4a.h \
+                       arch/qatomic_aarch64.h \
+
 
 QT_ARCH_CPP = $$QT_SOURCE_TREE/src/corelib/arch/$$QT_ARCH
 DEPENDPATH += $$QT_ARCH_CPP
diff --git a/src/corelib/arch/qatomic_aarch64.h b/src/corelib/arch/qatomic_aarch64.h
new file mode 100644
index 0000000..de61ca8
--- /dev/null
+++ b/src/corelib/arch/qatomic_aarch64.h
@@ -0,0 +1,335 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QATOMIC_AARCH64_H
+#define QATOMIC_AARCH64_H
+
+QT_BEGIN_HEADER
+
+QT_BEGIN_NAMESPACE
+
+#define Q_ATOMIC_INT_REFERENCE_COUNTING_IS_ALWAYS_NATIVE
+
+inline bool QBasicAtomicInt::isReferenceCountingNative()
+{ return true; }
+inline bool QBasicAtomicInt::isReferenceCountingWaitFree()
+{ return false; }
+
+#define Q_ATOMIC_INT_TEST_AND_SET_IS_ALWAYS_NATIVE
+
+inline bool QBasicAtomicInt::isTestAndSetNative()
+{ return true; }
+inline bool QBasicAtomicInt::isTestAndSetWaitFree()
+{ return false; }
+
+#define Q_ATOMIC_INT_FETCH_AND_STORE_IS_ALWAYS_NATIVE
+
+inline bool QBasicAtomicInt::isFetchAndStoreNative()
+{ return true; }
+inline bool QBasicAtomicInt::isFetchAndStoreWaitFree()
+{ return false; }
+
+#define Q_ATOMIC_INT_FETCH_AND_ADD_IS_ALWAYS_NATIVE
+
+inline bool QBasicAtomicInt::isFetchAndAddNative()
+{ return true; }
+inline bool QBasicAtomicInt::isFetchAndAddWaitFree()
+{ return false; }
+
+#define Q_ATOMIC_POINTER_TEST_AND_SET_IS_ALWAYS_NATIVE
+
+template <typename T>
+Q_INLINE_TEMPLATE bool QBasicAtomicPointer<T>::isTestAndSetNative()
+{ return true; }
+template <typename T>
+Q_INLINE_TEMPLATE bool QBasicAtomicPointer<T>::isTestAndSetWaitFree()
+{ return false; }
+
+#define Q_ATOMIC_POINTER_FETCH_AND_STORE_IS_ALWAYS_NATIVE
+
+template <typename T>
+Q_INLINE_TEMPLATE bool QBasicAtomicPointer<T>::isFetchAndStoreNative()
+{ return true; }
+template <typename T>
+Q_INLINE_TEMPLATE bool QBasicAtomicPointer<T>::isFetchAndStoreWaitFree()
+{ return false; }
+
+#define Q_ATOMIC_POINTER_FETCH_AND_ADD_IS_ALWAYS_NATIVE
+
+template <typename T>
+Q_INLINE_TEMPLATE bool QBasicAtomicPointer<T>::isFetchAndAddNative()
+{ return true; }
+template <typename T>
+Q_INLINE_TEMPLATE bool QBasicAtomicPointer<T>::isFetchAndAddWaitFree()
+{ return false; }
+
+#ifndef Q_DATA_MEMORY_BARRIER
+# define Q_DATA_MEMORY_BARRIER asm volatile("dmb sy\n":::"memory")
+#endif
+#ifndef Q_COMPILER_MEMORY_BARRIER
+# define Q_COMPILER_MEMORY_BARRIER asm volatile("":::"memory")
+#endif
+
+inline bool QBasicAtomicInt::ref()
+{
+    int newValue;
+
+    Q_COMPILER_MEMORY_BARRIER;
+    newValue = __atomic_add_fetch(&_q_value, 1, __ATOMIC_ACQ_REL);
+    Q_COMPILER_MEMORY_BARRIER;
+
+    return newValue != 0;
+}
+
+inline bool QBasicAtomicInt::deref()
+{
+    int newValue;
+
+    Q_COMPILER_MEMORY_BARRIER;
+    newValue = __atomic_sub_fetch(&_q_value, 1, __ATOMIC_ACQ_REL);
+    Q_COMPILER_MEMORY_BARRIER;
+
+    return newValue != 0;
+}
+
+inline bool QBasicAtomicInt::testAndSetRelaxed(int expectedValue, int newValue)
+{
+    bool val;
+
+    Q_COMPILER_MEMORY_BARRIER;
+    val =  __atomic_compare_exchange_n (&_q_value, &expectedValue, newValue,
+                                        false, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+    Q_COMPILER_MEMORY_BARRIER;
+    return val;
+}
+
+inline int QBasicAtomicInt::fetchAndStoreRelaxed(int newValue)
+{
+    int val;
+    Q_COMPILER_MEMORY_BARRIER;
+    val = __atomic_exchange_n(&_q_value, newValue, __ATOMIC_RELAXED);
+    Q_COMPILER_MEMORY_BARRIER;
+    return val;
+}
+
+inline int QBasicAtomicInt::fetchAndAddRelaxed(int valueToAdd)
+{
+    int val;
+    Q_COMPILER_MEMORY_BARRIER;
+    val = __atomic_fetch_add(&_q_value, valueToAdd, __ATOMIC_RELAXED);
+    Q_COMPILER_MEMORY_BARRIER;
+    return val;
+}
+
+template <typename T>
+Q_INLINE_TEMPLATE bool QBasicAtomicPointer<T>::testAndSetRelaxed(T *expectedValue, T *newValue)
+{
+    bool val;
+    Q_COMPILER_MEMORY_BARRIER;
+    val =  __atomic_compare_exchange_n (&_q_value, &expectedValue, newValue,
+                                        false, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+    Q_COMPILER_MEMORY_BARRIER;
+    return val;
+}
+
+template <typename T>
+Q_INLINE_TEMPLATE T *QBasicAtomicPointer<T>::fetchAndStoreRelaxed(T *newValue)
+{
+    T *val;
+    Q_COMPILER_MEMORY_BARRIER;
+    val = __atomic_exchange_n(&_q_value, newValue, __ATOMIC_RELAXED);
+    Q_COMPILER_MEMORY_BARRIER;
+    return val;
+}
+
+template <typename T>
+Q_INLINE_TEMPLATE T *QBasicAtomicPointer<T>::fetchAndAddRelaxed(qptrdiff valueToAdd)
+{
+    T *val;
+    Q_COMPILER_MEMORY_BARRIER;
+    val = __atomic_fetch_add(&_q_value, valueToAdd, __ATOMIC_RELAXED);
+    Q_COMPILER_MEMORY_BARRIER;
+    return val;
+}
+
+inline bool QBasicAtomicInt::testAndSetAcquire(int expectedValue, int newValue)
+{
+    bool returnValue = testAndSetRelaxed(expectedValue, newValue);
+    Q_DATA_MEMORY_BARRIER;
+    return returnValue;
+}
+
+inline bool QBasicAtomicInt::testAndSetRelease(int expectedValue, int newValue)
+{
+    Q_DATA_MEMORY_BARRIER;
+    return testAndSetRelaxed(expectedValue, newValue);
+}
+
+inline bool QBasicAtomicInt::testAndSetOrdered(int expectedValue, int newValue)
+{
+    Q_DATA_MEMORY_BARRIER;
+    bool returnValue = testAndSetRelaxed(expectedValue, newValue);
+    Q_COMPILER_MEMORY_BARRIER;
+    return returnValue;
+}
+
+inline int QBasicAtomicInt::fetchAndStoreAcquire(int newValue)
+{
+    int returnValue = fetchAndStoreRelaxed(newValue);
+    Q_DATA_MEMORY_BARRIER;
+    return returnValue;
+}
+
+inline int QBasicAtomicInt::fetchAndStoreRelease(int newValue)
+{
+    Q_DATA_MEMORY_BARRIER;
+    return fetchAndStoreRelaxed(newValue);
+}
+
+inline int QBasicAtomicInt::fetchAndStoreOrdered(int newValue)
+{
+    Q_DATA_MEMORY_BARRIER;
+    int returnValue = fetchAndStoreRelaxed(newValue);
+    Q_COMPILER_MEMORY_BARRIER;
+    return returnValue;
+}
+
+inline int QBasicAtomicInt::fetchAndAddAcquire(int valueToAdd)
+{
+    int returnValue = fetchAndAddRelaxed(valueToAdd);
+    Q_DATA_MEMORY_BARRIER;
+    return returnValue;
+}
+
+inline int QBasicAtomicInt::fetchAndAddRelease(int valueToAdd)
+{
+    Q_DATA_MEMORY_BARRIER;
+    return fetchAndAddRelaxed(valueToAdd);
+}
+
+inline int QBasicAtomicInt::fetchAndAddOrdered(int valueToAdd)
+{
+    Q_DATA_MEMORY_BARRIER;
+    int returnValue = fetchAndAddRelaxed(valueToAdd);
+    Q_COMPILER_MEMORY_BARRIER;
+    return returnValue;
+}
+
+template <typename T>
+Q_INLINE_TEMPLATE bool QBasicAtomicPointer<T>::testAndSetAcquire(T *expectedValue, T *newValue)
+{
+    bool returnValue = testAndSetRelaxed(expectedValue, newValue);
+    Q_DATA_MEMORY_BARRIER;
+    return returnValue;
+}
+
+template <typename T>
+Q_INLINE_TEMPLATE bool QBasicAtomicPointer<T>::testAndSetRelease(T *expectedValue, T *newValue)
+{
+    Q_DATA_MEMORY_BARRIER;
+    return testAndSetRelaxed(expectedValue, newValue);
+}
+
+template <typename T>
+Q_INLINE_TEMPLATE bool QBasicAtomicPointer<T>::testAndSetOrdered(T *expectedValue, T *newValue)
+{
+    Q_DATA_MEMORY_BARRIER;
+    bool returnValue = testAndSetAcquire(expectedValue, newValue);
+    Q_COMPILER_MEMORY_BARRIER;
+    return returnValue;
+}
+
+template <typename T>
+Q_INLINE_TEMPLATE T *QBasicAtomicPointer<T>::fetchAndStoreAcquire(T *newValue)
+{
+    T *returnValue = fetchAndStoreRelaxed(newValue);
+    Q_DATA_MEMORY_BARRIER;
+    return returnValue;
+}
+
+template <typename T>
+Q_INLINE_TEMPLATE T *QBasicAtomicPointer<T>::fetchAndStoreRelease(T *newValue)
+{
+    Q_DATA_MEMORY_BARRIER;
+    return fetchAndStoreRelaxed(newValue);
+}
+
+template <typename T>
+Q_INLINE_TEMPLATE T *QBasicAtomicPointer<T>::fetchAndStoreOrdered(T *newValue)
+{
+    Q_DATA_MEMORY_BARRIER;
+    T *returnValue = fetchAndStoreRelaxed(newValue);
+    Q_COMPILER_MEMORY_BARRIER;
+    return returnValue;
+}
+
+template <typename T>
+Q_INLINE_TEMPLATE T *QBasicAtomicPointer<T>::fetchAndAddAcquire(qptrdiff valueToAdd)
+{
+    T *returnValue = fetchAndAddRelaxed(valueToAdd);
+    Q_DATA_MEMORY_BARRIER;
+    return returnValue;
+}
+
+template <typename T>
+Q_INLINE_TEMPLATE T *QBasicAtomicPointer<T>::fetchAndAddRelease(qptrdiff valueToAdd)
+{
+    Q_DATA_MEMORY_BARRIER;
+    return fetchAndAddRelaxed(valueToAdd);
+}
+
+template <typename T>
+Q_INLINE_TEMPLATE T *QBasicAtomicPointer<T>::fetchAndAddOrdered(qptrdiff valueToAdd)
+{
+    Q_DATA_MEMORY_BARRIER;
+    T *returnValue = fetchAndAddRelaxed(valueToAdd);
+    Q_COMPILER_MEMORY_BARRIER;
+    return returnValue;
+}
+
+#undef Q_DATA_MEMORY_BARRIER
+#undef Q_COMPILER_MEMORY_BARRIER
+
+QT_END_NAMESPACE
+
+QT_END_HEADER
+
+#endif // QATOMIC_AARCH64_H
diff --git a/src/corelib/arch/qatomic_arch.h b/src/corelib/arch/qatomic_arch.h
index 141726c..3e96926 100644
--- a/src/corelib/arch/qatomic_arch.h
+++ b/src/corelib/arch/qatomic_arch.h
@@ -94,6 +94,8 @@ QT_BEGIN_HEADER
 #  include "QtCore/qatomic_sh4a.h"
 #elif defined(QT_ARCH_NACL)
 #  include "QtCore/qatomic_generic.h"
+#elif defined(QT_ARCH_AARCH64)
+#  include "QtCore/qatomic_aarch64.h"
 #else
 #  error "Qt has not been ported to this architecture"
 #endif
-- 
2.1.0