git: 92fc50b496ee - main - sys: Extract __bitcount* from sys/types.h to new sys/bitcount.h

From: Jessica Clarke <jrtc27_at_FreeBSD.org>
Date: Thu, 18 Aug 2022 01:46:43 UTC
The branch main has been updated by jrtc27:

URL: https://cgit.FreeBSD.org/src/commit/?id=92fc50b496ee8a5d0a0fc2025283e66351ae03d4

commit 92fc50b496ee8a5d0a0fc2025283e66351ae03d4
Author:     Jessica Clarke <jrtc27@FreeBSD.org>
AuthorDate: 2022-08-18 01:46:27 +0000
Commit:     Jessica Clarke <jrtc27@FreeBSD.org>
CommitDate: 2022-08-18 01:46:27 +0000

    sys: Extract __bitcount* from sys/types.h to new sys/bitcount.h
    
    This will allow the code to be reused by the cross-build sys/types.h
    wrapper in order to provide the APIs for greater compatibility. This
    also provides a path towards eventually removing the definitions from
    sys/types.h altogether if so desired by gradually migrating users to
    including sys/bitcount.h explicitly, but that is not the primary goal
    here.
    
    Note that the copyright header is a direct copu of sys/types.h's given
    that's where this code comes from. This could be replaced in future with
    a more specific one restricted to just the code in question, depending
    on what the copyright for that code is.
    
    Reviewed by:    emaste
    Differential Revision:  https://reviews.freebsd.org/D36132
---
 sys/sys/bitcount.h | 107 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 sys/sys/types.h    |  63 +------------------------------
 2 files changed, 108 insertions(+), 62 deletions(-)

diff --git a/sys/sys/bitcount.h b/sys/sys/bitcount.h
new file mode 100644
index 000000000000..7c792506bce5
--- /dev/null
+++ b/sys/sys/bitcount.h
@@ -0,0 +1,107 @@
+/*-
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 1982, 1986, 1991, 1993, 1994
+ *	The Regents of the University of California.  All rights reserved.
+ * (c) UNIX System Laboratories, Inc.
+ * All or some portions of this file are derived from material licensed
+ * to the University of California by American Telephone and Telegraph
+ * Co. or Unix System Laboratories, Inc. and are reproduced herein with
+ * the permission of UNIX System Laboratories, Inc.
+ *
+ * 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, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
+ *
+ *	@(#)types.h	8.6 (Berkeley) 2/19/95
+ * $FreeBSD$
+ */
+
+#ifndef _SYS_BITCOUNT_H_
+#define	_SYS_BITCOUNT_H_
+
+#include <sys/_types.h>
+
+#ifdef __POPCNT__
+#define	__bitcount64(x)	__builtin_popcountll((__uint64_t)(x))
+#define	__bitcount32(x)	__builtin_popcount((__uint32_t)(x))
+#define	__bitcount16(x)	__builtin_popcount((__uint16_t)(x))
+#define	__bitcountl(x)	__builtin_popcountl((unsigned long)(x))
+#define	__bitcount(x)	__builtin_popcount((unsigned int)(x))
+#else
+/*
+ * Population count algorithm using SWAR approach
+ * - "SIMD Within A Register".
+ */
+static __inline __uint16_t
+__bitcount16(__uint16_t _x)
+{
+
+	_x = (_x & 0x5555) + ((_x & 0xaaaa) >> 1);
+	_x = (_x & 0x3333) + ((_x & 0xcccc) >> 2);
+	_x = (_x + (_x >> 4)) & 0x0f0f;
+	_x = (_x + (_x >> 8)) & 0x00ff;
+	return (_x);
+}
+
+static __inline __uint32_t
+__bitcount32(__uint32_t _x)
+{
+
+	_x = (_x & 0x55555555) + ((_x & 0xaaaaaaaa) >> 1);
+	_x = (_x & 0x33333333) + ((_x & 0xcccccccc) >> 2);
+	_x = (_x + (_x >> 4)) & 0x0f0f0f0f;
+	_x = (_x + (_x >> 8));
+	_x = (_x + (_x >> 16)) & 0x000000ff;
+	return (_x);
+}
+
+#ifdef __LP64__
+static __inline __uint64_t
+__bitcount64(__uint64_t _x)
+{
+
+	_x = (_x & 0x5555555555555555) + ((_x & 0xaaaaaaaaaaaaaaaa) >> 1);
+	_x = (_x & 0x3333333333333333) + ((_x & 0xcccccccccccccccc) >> 2);
+	_x = (_x + (_x >> 4)) & 0x0f0f0f0f0f0f0f0f;
+	_x = (_x + (_x >> 8));
+	_x = (_x + (_x >> 16));
+	_x = (_x + (_x >> 32)) & 0x000000ff;
+	return (_x);
+}
+
+#define	__bitcountl(x)	__bitcount64((unsigned long)(x))
+#else
+static __inline __uint64_t
+__bitcount64(__uint64_t _x)
+{
+
+	return (__bitcount32(_x >> 32) + __bitcount32(_x));
+}
+
+#define	__bitcountl(x)	__bitcount32((unsigned long)(x))
+#endif
+#define	__bitcount(x)	__bitcount32((unsigned int)(x))
+#endif
+
+#endif /* !_SYS_BITCOUNT_H_ */
diff --git a/sys/sys/types.h b/sys/sys/types.h
index d37ab8b823dc..5db5679b11b5 100644
--- a/sys/sys/types.h
+++ b/sys/sys/types.h
@@ -310,68 +310,7 @@ typedef	_Bool	bool;
  * The following are all things that really shouldn't exist in this header,
  * since its purpose is to provide typedefs, not miscellaneous doodads.
  */
-
-#ifdef __POPCNT__
-#define	__bitcount64(x)	__builtin_popcountll((__uint64_t)(x))
-#define	__bitcount32(x)	__builtin_popcount((__uint32_t)(x))
-#define	__bitcount16(x)	__builtin_popcount((__uint16_t)(x))
-#define	__bitcountl(x)	__builtin_popcountl((unsigned long)(x))
-#define	__bitcount(x)	__builtin_popcount((unsigned int)(x))
-#else
-/*
- * Population count algorithm using SWAR approach
- * - "SIMD Within A Register".
- */
-static __inline __uint16_t
-__bitcount16(__uint16_t _x)
-{
-
-	_x = (_x & 0x5555) + ((_x & 0xaaaa) >> 1);
-	_x = (_x & 0x3333) + ((_x & 0xcccc) >> 2);
-	_x = (_x + (_x >> 4)) & 0x0f0f;
-	_x = (_x + (_x >> 8)) & 0x00ff;
-	return (_x);
-}
-
-static __inline __uint32_t
-__bitcount32(__uint32_t _x)
-{
-
-	_x = (_x & 0x55555555) + ((_x & 0xaaaaaaaa) >> 1);
-	_x = (_x & 0x33333333) + ((_x & 0xcccccccc) >> 2);
-	_x = (_x + (_x >> 4)) & 0x0f0f0f0f;
-	_x = (_x + (_x >> 8));
-	_x = (_x + (_x >> 16)) & 0x000000ff;
-	return (_x);
-}
-
-#ifdef __LP64__
-static __inline __uint64_t
-__bitcount64(__uint64_t _x)
-{
-
-	_x = (_x & 0x5555555555555555) + ((_x & 0xaaaaaaaaaaaaaaaa) >> 1);
-	_x = (_x & 0x3333333333333333) + ((_x & 0xcccccccccccccccc) >> 2);
-	_x = (_x + (_x >> 4)) & 0x0f0f0f0f0f0f0f0f;
-	_x = (_x + (_x >> 8));
-	_x = (_x + (_x >> 16));
-	_x = (_x + (_x >> 32)) & 0x000000ff;
-	return (_x);
-}
-
-#define	__bitcountl(x)	__bitcount64((unsigned long)(x))
-#else
-static __inline __uint64_t
-__bitcount64(__uint64_t _x)
-{
-
-	return (__bitcount32(_x >> 32) + __bitcount32(_x));
-}
-
-#define	__bitcountl(x)	__bitcount32((unsigned long)(x))
-#endif
-#define	__bitcount(x)	__bitcount32((unsigned int)(x))
-#endif
+#include <sys/bitcount.h>
 
 #if __BSD_VISIBLE