Cleanup and refactor our atomic library.

This commit:
* Removes most of all dirty internal details from public atomi_ops.h file, and move them into /intern private subdir.
* Removes unused 'architectures' (__apple__ and jemalloc).
* Split each implementation into its own file.
* Makes use of C99's limits.h system header to determine pointer and int size, instead of using fix hardcoded list of architectures.
* Introduces new 'faked' atomics ops for floats.

Note that we may add a lot more real and 'faked' atomic operations over integers and floats
(multiplication, division, bitshift, bitwise booleans, etc.), as needs arise.

Reviewers: sergey, campbellbarton

Differential Revision: https://developer.blender.org/D1982

1 files changed, 146 insertions, 0 deletions

diff --git a/intern/atomic/intern/atomic_ops_ext.h b/intern/atomic/intern/atomic_ops_ext.h
new file mode 100644
index 00000000000..4065299d2ea
--- /dev/null
+++ b/intern/atomic/intern/atomic_ops_ext.h
@@ -0,0 +1,146 @@
+/*
+ * Original code from jemalloc with this license:
+ *
+ * Copyright (C) 2002-2013 Jason Evans <jasone@canonware.com>.
+ * All rights reserved.
+ * Copyright (C) 2007-2012 Mozilla Foundation.  All rights reserved.
+ * Copyright (C) 2009-2013 Facebook, Inc.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 1. Redistributions of source code must retain the above copyright notice(s),
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice(s),
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY EXPRESS
+ * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDER(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2016 Blender Foundation.
+ * All rights reserved.
+ *
+ * The Original Code is: adapted from jemalloc.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+#ifndef __ATOMIC_OPS_EXT_H__
+#define __ATOMIC_OPS_EXT_H__
+
+#include "atomic_ops_utils.h"
+
+/******************************************************************************/
+/* size_t operations. */
+ATOMIC_INLINE size_t atomic_add_z(size_t *p, size_t x)
+{
+	assert(sizeof(size_t) == LG_SIZEOF_PTR);
+
+#if (LG_SIZEOF_PTR == 8)
+	return (size_t)atomic_add_uint64((uint64_t *)p, (uint64_t)x);
+#elif (LG_SIZEOF_PTR == 4)
+	return (size_t)atomic_add_uint32((uint32_t *)p, (uint32_t)x);
+#endif
+}
+
+ATOMIC_INLINE size_t atomic_sub_z(size_t *p, size_t x)
+{
+	assert(sizeof(size_t) == LG_SIZEOF_PTR);
+
+#if (LG_SIZEOF_PTR == 8)
+	return (size_t)atomic_add_uint64((uint64_t *)p, (uint64_t)-((int64_t)x));
+#elif (LG_SIZEOF_PTR == 4)
+	return (size_t)atomic_add_uint32((uint32_t *)p, (uint32_t)-((int32_t)x));
+#endif
+}
+
+ATOMIC_INLINE size_t atomic_cas_z(size_t *v, size_t old, size_t _new)
+{
+	assert(sizeof(size_t) == LG_SIZEOF_PTR);
+
+#if (LG_SIZEOF_PTR == 8)
+	return (size_t)atomic_cas_uint64((uint64_t *)v, (uint64_t)old, (uint64_t)_new);
+#elif (LG_SIZEOF_PTR == 4)
+	return (size_t)atomic_cas_uint32((uint32_t *)v, (uint32_t)old, (uint32_t)_new);
+#endif
+}
+
+/******************************************************************************/
+/* unsigned operations. */
+ATOMIC_INLINE unsigned atomic_add_u(unsigned *p, unsigned x)
+{
+	assert(sizeof(unsigned) == LG_SIZEOF_INT);
+
+#if (LG_SIZEOF_INT == 8)
+	return (unsigned)atomic_add_uint64((uint64_t *)p, (uint64_t)x);
+#elif (LG_SIZEOF_INT == 4)
+	return (unsigned)atomic_add_uint32((uint32_t *)p, (uint32_t)x);
+#endif
+}
+
+ATOMIC_INLINE unsigned atomic_sub_u(unsigned *p, unsigned x)
+{
+	assert(sizeof(unsigned) == LG_SIZEOF_INT);
+
+#if (LG_SIZEOF_INT == 8)
+	return (unsigned)atomic_add_uint64((uint64_t *)p, (uint64_t)-((int64_t)x));
+#elif (LG_SIZEOF_INT == 4)
+	return (unsigned)atomic_add_uint32((uint32_t *)p, (uint32_t)-((int32_t)x));
+#endif
+}
+
+ATOMIC_INLINE unsigned atomic_cas_u(unsigned *v, unsigned old, unsigned _new)
+{
+	assert(sizeof(unsigned) == LG_SIZEOF_INT);
+
+#if (LG_SIZEOF_INT == 8)
+	return (unsigned)atomic_cas_uint64((uint64_t *)v, (uint64_t)old, (uint64_t)_new);
+#elif (LG_SIZEOF_INT == 4)
+	return (unsigned)atomic_cas_uint32((uint32_t *)v, (uint32_t)old, (uint32_t)_new);
+#endif
+}
+
+/******************************************************************************/
+/* float operations. */
+
+ATOMIC_INLINE float atomic_add_fl(float *p, const float x)
+{
+	assert(sizeof(float) == sizeof(uint32_t));
+
+	float oldval, newval;
+	uint32_t prevval;
+
+	do {  /* Note that since collisions are unlikely, loop will nearly always run once. */
+		oldval = *p;
+		newval = oldval + x;
+		prevval = atomic_cas_uint32((uint32_t *)p, *(uint32_t *)(&oldval), *(uint32_t *)(&newval));
+	} while (UNLIKELY(prevval != *(uint32_t *)(&oldval)));
+
+	return newval;
+}
+
+#endif /* __ATOMIC_OPS_EXT_H__ */