[FFmpeg-cvslog] aacdec: fix undefined shifts

[Mans Rullgard]

ffmpeg | branch: release/0.7 | Mans Rullgard <mans at mansr.com> | Sat Oct  8 13:41:23 2011 +0100| [c2c83dcb322504807388f804d73d75a45fab004b] | committer: Michael Niedermayer

aacdec: fix undefined shifts

Since nnz can be zero, this is needed to avoid a shift by 32.

Signed-off-by: Mans Rullgard <mans at mansr.com>
(cherry picked from commit d12294304acd82cb219e3f66ca9cd6efb2194fa4)

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c2c83dcb322504807388f804d73d75a45fab004b
---

 libavcodec/aacdec.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/aacdec.c b/libavcodec/aacdec.c
index 6cc0cec..e9f2cc5 100644
--- a/libavcodec/aacdec.c
+++ b/libavcodec/aacdec.c
@@ -1090,7 +1090,7 @@ static int decode_spectrum_and_dequant(AACContext *ac, float coef[1024],
                             GET_VLC(code, re, gb, vlc_tab, 8, 2);
                             cb_idx = cb_vector_idx[code];
                             nnz = cb_idx >> 8 & 15;
-                            bits = SHOW_UBITS(re, gb, nnz) << (32-nnz);
+                            bits = nnz ? GET_CACHE(re, gb) : 0;
                             LAST_SKIP_BITS(re, gb, nnz);
                             cf = VMUL4S(cf, vq, cb_idx, bits, sf + idx);
                         } while (len -= 4);
@@ -1130,7 +1130,7 @@ static int decode_spectrum_and_dequant(AACContext *ac, float coef[1024],
                             GET_VLC(code, re, gb, vlc_tab, 8, 2);
                             cb_idx = cb_vector_idx[code];
                             nnz = cb_idx >> 8 & 15;
-                            sign = SHOW_UBITS(re, gb, nnz) << (cb_idx >> 12);
+                            sign = nnz ? SHOW_UBITS(re, gb, nnz) << (cb_idx >> 12) : 0;
                             LAST_SKIP_BITS(re, gb, nnz);
                             cf = VMUL2S(cf, vq, cb_idx, sign, sf + idx);
                         } while (len -= 2);