From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:57811) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UD8mR-0005tQ-Bx for qemu-devel@nongnu.org; Wed, 06 Mar 2013 02:28:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UD8mO-00036T-0o for qemu-devel@nongnu.org; Wed, 06 Mar 2013 02:28:51 -0500 Received: from mail-ia0-x22e.google.com ([2607:f8b0:4001:c02::22e]:36106) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UD8mN-00036J-HL for qemu-devel@nongnu.org; Wed, 06 Mar 2013 02:28:47 -0500 Received: by mail-ia0-f174.google.com with SMTP id u20so7015770iag.19 for ; Tue, 05 Mar 2013 23:28:47 -0800 (PST) From: Kuo-Jung Su Date: Wed, 6 Mar 2013 15:27:30 +0800 Message-Id: <1362554857-3896-18-git-send-email-dantesu@gmail.com> In-Reply-To: <1362554857-3896-1-git-send-email-dantesu@gmail.com> References: <1362554857-3896-1-git-send-email-dantesu@gmail.com> Subject: [Qemu-devel] [PATCH v6 17/24] qemu/bitops.h: add the bit ordering reversal functions stolen from linux List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , i.mitsyanko@samsung.com, Blue Swirl , Kuo-Jung Su , Paul Brook , Andreas , fred.konrad@greensocs.com Signed-off-by: Kuo-Jung Su --- include/qemu/bitops.h | 63 ++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 62 insertions(+), 1 deletion(-) diff --git a/include/qemu/bitops.h b/include/qemu/bitops.h index affcc96..920d028 100644 --- a/include/qemu/bitops.h +++ b/include/qemu/bitops.h @@ -3,7 +3,8 @@ * * Copyright (C) 2010 Corentin Chary * - * Mostly inspired by (stolen from) linux/bitmap.h and linux/bitops.h + * Mostly inspired by (stolen from) linux/bitmap.h, linux/bitops.h + * and linux/bitrev.h * * This work is licensed under the terms of the GNU LGPL, version 2.1 or later. * See the COPYING.LIB file in the top-level directory. @@ -273,4 +274,64 @@ static inline uint64_t deposit64(uint64_t value, int start, int length, return (value & ~mask) | ((fieldval << start) & mask); } +/** + * bitrev8: + * @value: the value to reverse bit ordering from + * + * Reverse the 8 bit input @value + * + * Returns: the input @value with reversed bit ordering + */ +static inline uint8_t bitrev8(uint8_t value) +{ + int i; + uint8_t ret = 0; + for (i = 0; i < 8; ++i) { + if (value & BIT(i)) { + ret |= BIT(7 - i); + } + } + return ret; +} + +/** + * bitrev16: + * @value: the value to reverse bit ordering from + * + * Reverse the 16 bit input @value + * + * Returns: the input @value with reversed bit ordering + */ +static inline uint16_t bitrev16(uint16_t value) +{ + return (bitrev8(value & 0xff) << 8) | bitrev8(value >> 8); +} + +/** + * bitrev32: + * @value: the value to reverse bit ordering from + * + * Reverse the 32 bit input @value + * + * Returns: the input @value with reversed bit ordering + */ +static inline uint32_t bitrev32(uint32_t value) +{ + return (bitrev16(value & 0xffff) << 16) | bitrev16(value >> 16); +} + +/** + * bitrev64: + * @value: the value to reverse bit ordering from + * + * Reverse the 64 bit input @value + * + * Returns: the input @value with reversed bit ordering + */ +static inline uint64_t bitrev64(uint64_t value) +{ + return ((uint64_t)bitrev32(value & 0xffffffffULL) << 32) + | (uint64_t)bitrev32(value >> 32); +} + #endif -- 1.7.9.5