Index: flac/src/libFLAC/bitmath.c |
=================================================================== |
--- flac/src/libFLAC/bitmath.c (revision 0) |
+++ flac/src/libFLAC/bitmath.c (revision 0) |
@@ -0,0 +1,149 @@ |
+/* libFLAC - Free Lossless Audio Codec library |
+ * Copyright (C) 2001,2002,2003,2004,2005,2006,2007 Josh Coalson |
+ * |
+ * Redistribution and use in source and binary forms, with or without |
+ * modification, are permitted provided that the following conditions |
+ * are met: |
+ * |
+ * - Redistributions of source code must retain the above copyright |
+ * notice, this list of conditions and the following disclaimer. |
+ * |
+ * - 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. |
+ * |
+ * - Neither the name of the Xiph.org Foundation 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 COPYRIGHT HOLDERS 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 FOUNDATION 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. |
+ */ |
+ |
+#if HAVE_CONFIG_H |
+# include <config.h> |
+#endif |
+ |
+#include "private/bitmath.h" |
+#include "FLAC/assert.h" |
+ |
+/* An example of what FLAC__bitmath_ilog2() computes: |
+ * |
+ * ilog2( 0) = assertion failure |
+ * ilog2( 1) = 0 |
+ * ilog2( 2) = 1 |
+ * ilog2( 3) = 1 |
+ * ilog2( 4) = 2 |
+ * ilog2( 5) = 2 |
+ * ilog2( 6) = 2 |
+ * ilog2( 7) = 2 |
+ * ilog2( 8) = 3 |
+ * ilog2( 9) = 3 |
+ * ilog2(10) = 3 |
+ * ilog2(11) = 3 |
+ * ilog2(12) = 3 |
+ * ilog2(13) = 3 |
+ * ilog2(14) = 3 |
+ * ilog2(15) = 3 |
+ * ilog2(16) = 4 |
+ * ilog2(17) = 4 |
+ * ilog2(18) = 4 |
+ */ |
+unsigned FLAC__bitmath_ilog2(FLAC__uint32 v) |
+{ |
+ unsigned l = 0; |
+ FLAC__ASSERT(v > 0); |
+ while(v >>= 1) |
+ l++; |
+ return l; |
+} |
+ |
+unsigned FLAC__bitmath_ilog2_wide(FLAC__uint64 v) |
+{ |
+ unsigned l = 0; |
+ FLAC__ASSERT(v > 0); |
+ while(v >>= 1) |
+ l++; |
+ return l; |
+} |
+ |
+/* An example of what FLAC__bitmath_silog2() computes: |
+ * |
+ * silog2(-10) = 5 |
+ * silog2(- 9) = 5 |
+ * silog2(- 8) = 4 |
+ * silog2(- 7) = 4 |
+ * silog2(- 6) = 4 |
+ * silog2(- 5) = 4 |
+ * silog2(- 4) = 3 |
+ * silog2(- 3) = 3 |
+ * silog2(- 2) = 2 |
+ * silog2(- 1) = 2 |
+ * silog2( 0) = 0 |
+ * silog2( 1) = 2 |
+ * silog2( 2) = 3 |
+ * silog2( 3) = 3 |
+ * silog2( 4) = 4 |
+ * silog2( 5) = 4 |
+ * silog2( 6) = 4 |
+ * silog2( 7) = 4 |
+ * silog2( 8) = 5 |
+ * silog2( 9) = 5 |
+ * silog2( 10) = 5 |
+ */ |
+unsigned FLAC__bitmath_silog2(int v) |
+{ |
+ while(1) { |
+ if(v == 0) { |
+ return 0; |
+ } |
+ else if(v > 0) { |
+ unsigned l = 0; |
+ while(v) { |
+ l++; |
+ v >>= 1; |
+ } |
+ return l+1; |
+ } |
+ else if(v == -1) { |
+ return 2; |
+ } |
+ else { |
+ v++; |
+ v = -v; |
+ } |
+ } |
+} |
+ |
+unsigned FLAC__bitmath_silog2_wide(FLAC__int64 v) |
+{ |
+ while(1) { |
+ if(v == 0) { |
+ return 0; |
+ } |
+ else if(v > 0) { |
+ unsigned l = 0; |
+ while(v) { |
+ l++; |
+ v >>= 1; |
+ } |
+ return l+1; |
+ } |
+ else if(v == -1) { |
+ return 2; |
+ } |
+ else { |
+ v++; |
+ v = -v; |
+ } |
+ } |
+} |
Property changes on: flac/src/libFLAC/bitmath.c |
___________________________________________________________________ |
Added: svn:eol-style |
+ LF |