media/libopus/celt/ecintrin.h@ac0c01689b40 (annotated)
media/libopus/celt/ecintrin.h
Thu, 15 Jan 2015 15:59:08 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Thu, 15 Jan 2015 15:59:08 +0100
- branch
- TOR_BUG_9701
- changeset 10
- ac0c01689b40
- permissions
- -rw-r--r--
Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
| michael@0 | 1 | /* Copyright (c) 2003-2008 Timothy B. Terriberry |
| michael@0 | 2 | Copyright (c) 2008 Xiph.Org Foundation */ |
| michael@0 | 3 | /* |
| michael@0 | 4 | Redistribution and use in source and binary forms, with or without |
| michael@0 | 5 | modification, are permitted provided that the following conditions |
| michael@0 | 6 | are met: |
| michael@0 | 7 | |
| michael@0 | 8 | - Redistributions of source code must retain the above copyright |
| michael@0 | 9 | notice, this list of conditions and the following disclaimer. |
| michael@0 | 10 | |
| michael@0 | 11 | - Redistributions in binary form must reproduce the above copyright |
| michael@0 | 12 | notice, this list of conditions and the following disclaimer in the |
| michael@0 | 13 | documentation and/or other materials provided with the distribution. |
| michael@0 | 14 | |
| michael@0 | 15 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| michael@0 | 16 | ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| michael@0 | 17 | LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| michael@0 | 18 | A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER |
| michael@0 | 19 | OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| michael@0 | 20 | EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| michael@0 | 21 | PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| michael@0 | 22 | PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
| michael@0 | 23 | LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| michael@0 | 24 | NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| michael@0 | 25 | SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| michael@0 | 26 | */ |
| michael@0 | 27 | |
| michael@0 | 28 | /*Some common macros for potential platform-specific optimization.*/ |
| michael@0 | 29 | #include "opus_types.h" |
| michael@0 | 30 | #include <math.h> |
| michael@0 | 31 | #include <limits.h> |
| michael@0 | 32 | #include "arch.h" |
| michael@0 | 33 | #if !defined(_ecintrin_H) |
| michael@0 | 34 | # define _ecintrin_H (1) |
| michael@0 | 35 | |
| michael@0 | 36 | /*Some specific platforms may have optimized intrinsic or OPUS_INLINE assembly |
| michael@0 | 37 | versions of these functions which can substantially improve performance. |
| michael@0 | 38 | We define macros for them to allow easy incorporation of these non-ANSI |
| michael@0 | 39 | features.*/ |
| michael@0 | 40 | |
| michael@0 | 41 | /*Modern gcc (4.x) can compile the naive versions of min and max with cmov if |
| michael@0 | 42 | given an appropriate architecture, but the branchless bit-twiddling versions |
| michael@0 | 43 | are just as fast, and do not require any special target architecture. |
| michael@0 | 44 | Earlier gcc versions (3.x) compiled both code to the same assembly |
| michael@0 | 45 | instructions, because of the way they represented ((_b)>(_a)) internally.*/ |
| michael@0 | 46 | # define EC_MINI(_a,_b) ((_a)+(((_b)-(_a))&-((_b)<(_a)))) |
| michael@0 | 47 | |
| michael@0 | 48 | /*Count leading zeros. |
| michael@0 | 49 | This macro should only be used for implementing ec_ilog(), if it is defined. |
| michael@0 | 50 | All other code should use EC_ILOG() instead.*/ |
| michael@0 | 51 | #if defined(_MSC_VER) && (_MSC_VER >= 1400) |
| michael@0 | 52 | # include <intrin.h> |
| michael@0 | 53 | /*In _DEBUG mode this is not an intrinsic by default.*/ |
| michael@0 | 54 | # pragma intrinsic(_BitScanReverse) |
| michael@0 | 55 | |
| michael@0 | 56 | static __inline int ec_bsr(unsigned long _x){ |
| michael@0 | 57 | unsigned long ret; |
| michael@0 | 58 | _BitScanReverse(&ret,_x); |
| michael@0 | 59 | return (int)ret; |
| michael@0 | 60 | } |
| michael@0 | 61 | # define EC_CLZ0 (1) |
| michael@0 | 62 | # define EC_CLZ(_x) (-ec_bsr(_x)) |
| michael@0 | 63 | #elif defined(ENABLE_TI_DSPLIB) |
| michael@0 | 64 | # include "dsplib.h" |
| michael@0 | 65 | # define EC_CLZ0 (31) |
| michael@0 | 66 | # define EC_CLZ(_x) (_lnorm(_x)) |
| michael@0 | 67 | #elif __GNUC_PREREQ(3,4) |
| michael@0 | 68 | # if INT_MAX>=2147483647 |
| michael@0 | 69 | # define EC_CLZ0 ((int)sizeof(unsigned)*CHAR_BIT) |
| michael@0 | 70 | # define EC_CLZ(_x) (__builtin_clz(_x)) |
| michael@0 | 71 | # elif LONG_MAX>=2147483647L |
| michael@0 | 72 | # define EC_CLZ0 ((int)sizeof(unsigned long)*CHAR_BIT) |
| michael@0 | 73 | # define EC_CLZ(_x) (__builtin_clzl(_x)) |
| michael@0 | 74 | # endif |
| michael@0 | 75 | #endif |
| michael@0 | 76 | |
| michael@0 | 77 | #if defined(EC_CLZ) |
| michael@0 | 78 | /*Note that __builtin_clz is not defined when _x==0, according to the gcc |
| michael@0 | 79 | documentation (and that of the BSR instruction that implements it on x86). |
| michael@0 | 80 | The majority of the time we can never pass it zero. |
| michael@0 | 81 | When we need to, it can be special cased.*/ |
| michael@0 | 82 | # define EC_ILOG(_x) (EC_CLZ0-EC_CLZ(_x)) |
| michael@0 | 83 | #else |
| michael@0 | 84 | int ec_ilog(opus_uint32 _v); |
| michael@0 | 85 | # define EC_ILOG(_x) (ec_ilog(_x)) |
| michael@0 | 86 | #endif |
| michael@0 | 87 | #endif |
