[Libav-user] Reference app with ffmpeg n1.2 libs that works on IOS ?

[Michael Niedermayer]

On Tue, Apr 02, 2013 at 08:38:18PM +0200, Lars Hammarstrand wrote:
> 2013/4/2 Carl Eugen Hoyos <cehoyos at ag.or.at>
> 
> > Lars Hammarstrand <lars.hammarstrand at ...> writes:
> >
> > > (gdb) disass $pc-32,$pc+32
> >
> > Please add the register dump, some developers can
> > see the problem if it is present.
> >
> >
> 
> Complete trace:
> $ *uname -a*
> Darwin Lars-iPhone-4 11.0.0 Darwin Kernel Version 11.0.0: Sun Apr  8
> 21:51:26 PDT 2012; root:xnu-1878.11.10~1/RELEASE_ARM_S5L8930X iPhone3,1 arm
> N90AP Darwin
> 
> $ *gdb ffmpeg*
> GNU gdb 6.3.50-20050815 (Apple version gdb-1821) (Fri Jun 29 08:41:41 UTC
> 2012)
> Copyright 2004 Free Software Foundation, Inc.
> GDB is free software, covered by the GNU General Public License, and you are
> welcome to change it and/or distribute copies of it under certain
> conditions.
> Type "show copying" to see the conditions.
> There is absolutely no warranty for GDB.  Type "show warranty" for details.
> This GDB was configured as "arm-apple-darwin"...Reading symbols for shared
> libraries . done
> 
> (gdb) *r ffmpeg -i
> http://techslides.com/demos/sample-videos/small.mp4-acodec copy
> -vcodec copy output.mp4
> *
> Starting program: /ffmpeg-n1.2/ffmpeg ffmpeg -i
> http://techslides.com/demos/sample-videos/small.mp4 -acodec copy -vcodec
> copy output.mp4
> Reading symbols for shared libraries ......................... done
> 
> Program received signal EXC_BAD_INSTRUCTION, Illegal instruction/operand.
> ff_pred8x8_128_dc_neon () at h264pred_neon.S:405
> Line number 405 out of range; h264pred_neon.S has 359 lines.
> 
> (gdb) *bt*
> #0  ff_pred8x8_128_dc_neon () at h264pred_neon.S:405
> #1  0x003fc75a in hl_decode_mb_simple_8 (h=0x0) at h264_mb_template.c:161
> #2  0x003fdad8 in ff_h264_hl_decode_mb (h=<value temporarily unavailable,
> due to optimizations>) at /ffmpeg-n1.2/libavcodec/h264.c:2415
> #3  0x00401da4 in decode_slice (avctx=<value temporarily unavailable, due
> to optimizations>, arg=<value temporarily unavailable, due to
> optimizations>) at /ffmpeg-n1.2/libavcodec/h264.c:4266
> #4  0x00402380 in execute_decode_slices () at
> /ffmpeg-n1.2/libavcodec/h264.c:4355
> #5  0x00402dec in decode_nal_units (h=0xf00000, buf=0xd25484 "",
> buf_size=4207149, parse_extradata=0) at /ffmpeg-n1.2/libavcodec/h264.c:4699
> #6  0x004033d6 in decode_frame (avctx=0x13b5a00, data=0x0,
> got_frame=0x2fdfef84, avpkt=<value temporarily unavailable, due to
> optimizations>) at /ffmpeg-n1.2/libavcodec/h264.c:4811
> #7  0x003247ce in avcodec_decode_video2 (avctx=0x13b5a00, picture=0xe4bb40,
> got_picture_ptr=0x10, avpkt=0x2fdfef20) at
> /ffmpeg-n1.2/libavcodec/utils.c:1690
> #8  0x00067c16 in try_decode_frame (st=0xe4ad30, avpkt=<value temporarily
> unavailable, due to optimizations>, options=0x0) at
> /ffmpeg-n1.2/libavformat/utils.c:2514
> #9  0x0006c468 in avformat_find_stream_info (ic=0xd18004,
> options=0x2fe25a14) at /ffmpeg-n1.2/libavformat/utils.c:2946
> #10 0x00004448 in open_input_file (o=0x2fdff36c, filename=<value
> temporarily unavailable, due to optimizations>) at
> /ffmpeg-n1.2/ffmpeg_opt.c:786
> #11 0x00003de8 in open_files (l=0x0, inout=0x0, open_file=0x5f5944
> <groups>) at /ffmpeg-n1.2/ffmpeg_opt.c:2307
> #12 0x00004058 in ffmpeg_parse_options (argc=<value temporarily
> unavailable, due to optimizations>, argv=<value temporarily unavailable,
> due to optimizations>) at /ffmpeg-n1.2/ffmpeg_opt.c:2344
> #13 0x00010c30 in main (argc=<value temporarily unavailable, due to
> optimizations>, argv=<value temporarily unavailable, due to optimizations>)
> at /ffmpeg-n1.2/ffmpeg.c:3317
> Current language:  auto; currently asm
> 
> (gdb) *disass $pc-32,$pc+32*
> Dump of assembler code for function ff_pred8x8_top_dc_neon:
> 0x00398b74 <ff_pred8x8_top_dc_neon+0>: andeq lr, r1, #163840 ; 0x28000
> 0x00398b78 <ff_pred8x8_top_dc_neon+4>: ldreq pc, [pc, -r2, lsr #18]
> 0x00398b7c <ff_pred8x8_top_dc_neon+8>: addeq pc, r0, #704 ; 0x2c0
> 0x00398b80 <ff_pred8x8_top_dc_neon+12>: bleq 0x7d47c8 <noise_table+2408>
> 0x00398b84 <ff_pred8x8_top_dc_neon+16>: ldmdaeq r0, {r1, r2, r3, r7, r8,
> r9, r10, r11, sp, lr, pc}^
> 0x00398b88 <ff_pred8x8_top_dc_neon+20>: stcne 15, cr15, [r0], {179}
> 0x00398b8c <ff_pred8x8_top_dc_neon+24>: stceq 15, cr15, [r0], {177}
> 0x00398b90 <ff_pred8x8_top_dc_neon+28>: strheq pc, [r1], r10
> 0x00398b94 <ff_pred8x8_top_dc_neon+32>: svclt 0x0000e04a
> End of assembler dump.
> 
> (gdb) *info all-registers*
[...]

> pc             0x398b6c 3771244

iam not an arm expert but the address pc is at doesnt seem to be part
of the disassembly


[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Democracy is the form of government in which you can choose your dictator
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