This is equivalent to
http://git.videolan.org/?p=ffmpeg.git;a=patch;h=9a83adaf346bc5e38183427b2bd11084c11d1c8b

--- gst-libs/ext/libav/libavcodec/arm/ac3dsp_armv6.S	2011-11-02 16:16:24.000000000 +0100
+++ gst-libs/ext/libav/libavcodec/arm/ac3dsp_armv6.S	2015-07-11 19:49:51.024078695 +0200
@@ -37,14 +37,14 @@
         ldrb            r10, [r4], #1
 1:
         ldrsh           r9,  [r0], #2                   @ mask[band]
-        movw            r8,  #0x1fe0
+        mov             r8,  #0xff0
         sub             r9,  r9,  r12                   @   - snr_offset
         mov             r11, r10
         ldrb            r10, [r4], #1                   @ band_start_tab[band++]
         subs            r9,  r9,  r5                    @   - floor
         movlt           r9,  #0
         cmp             r10, r3                         @   - end
-        and             r9,  r9,  r8                    @   & 0x1fe0
+        and             r9,  r9,  r8, lsl #1            @   & 0x1fe0
         subgt           r8,  r3,  r11
         suble           r8,  r10, r11
         add             r9,  r9,  r5                    @   + floor => m
