Crash in FFT routines, with MMX enabled.

[Marc Esipovich]

VideoLAN Client - version 0.2.90 Ourumov - (C)1996-2001 VideoLAN

[New Thread 2049 (runnable)]
[New Thread 1026 (runnable)]
[New Thread 2051 (runnable)]
[New Thread 3076 (runnable)]
[New Thread 4101 (runnable)]
[New Thread 5126 (runnable)]

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 3076 (runnable)]
0x80b52a9 in fft_asmb_sse (k=134958963, x=0x2, wTB=0x8159e20, d=0x8159e60, 
    d_3=0x80ce840) at ac3_srfft_sse.c:222
222         __asm__ __volatile__ (
(gdb) bt
#0  0x80b52a9 in fft_asmb_sse (k=134958963, x=0x2, wTB=0x8159e20, d=0x8159e60, 
    d_3=0x80ce840) at ac3_srfft_sse.c:222
#1  0x8159e60 in ?? ()
#2  0x8159e60 in ?? ()
(gdb) info registers 
eax            0x8159730        135632688
ecx            0x20     32
edx            0x80ce848        135063624
ebx            0x80b5128        134959400
esp            0xbf3ffc44       0xbf3ffc44
ebp            0xbf3ffc60       0xbf3ffc60
esi            0x80ce868        135063656
edi            0x8159770        135632752
p            0x80b52a9        0x80b52a9
eflags         0x210202 2163202
cs             0x23     35
ss             0x2b     43
ds             0x2b     43
es             0x2b     43
fs             0x0      0
gs             0x0      0
fctrl          0x37f    895
fstat          0x20     32
ftag           0xffff   65535
fiseg          0x23     35
fioff          0x8065ee1        134635233
foseg          0x2b     43
fooff          0x859c   34204
fop            0x5d8    1496
(gdb) disassemble $eip
Dump of assembler code for function fft_asmb_sse:
0x80b5234 <fft_asmb_sse>:       push   %edi
0x80b5235 <fft_asmb_sse+1>:     push   %esi
0x80b5236 <fft_asmb_sse+2>:     mov    0xc(%esp,1),%ecx
0x80b523a <fft_asmb_sse+6>:     mov    0x10(%esp,1),%eax
0x80b523e <fft_asmb_sse+10>:    mov    0x14(%esp,1),%edi
0x80b5242 <fft_asmb_sse+14>:    mov    0x18(%esp,1),%edx
0x80b5246 <fft_asmb_sse+18>:    mov    0x1c(%esp,1),%esi
0x80b524a <fft_asmb_sse+22>:    lea    0x0(%esi),%esi
0x80b5250 <fft_asmb_sse+28>:    push   %ebp
....
0x80b52a0 <fft_asmb_sse+108>:   shufps $0xb1,%xmm6,%xmm7
0x80b52a4 <fft_asmb_sse+112>:   mov    $0x80b5128,%ebx
0x80b52a9 <fft_asmb_sse+117>:   movaps (%ebx),%xmm4
0x80b52ac <fft_asmb_sse+120>:   mulps  %xmm4,%xmm7
0x80b52af <fft_asmb_sse+123>:   addps  %xmm7,%xmm5
0x80b52b2 <fft_asmb_sse+126>:   movlhps %xmm5,%xmm1
0x80b52b5 <fft_asmb_sse+129>:   shufps $0xe4,%xmm5,%xmm2


A different session:

(gdb) break fft_asmb_sse
Breakpoint 1 at 0x80b5234: file ac3_srfft_sse.c, line 221.
(gdb) run
Starting program: /archive/vlc-0.2.90/./vlc 
...
[New Thread 1024 (runnable)]
VideoLAN Client - version 0.2.90 Ourumov - (C)1996-2001 VideoLAN

[New Thread 2049 (runnable)]
[New Thread 1026 (runnable)]
[New Thread 2051 (runnable)]
[New Thread 3076 (runnable)]
[New Thread 4101 (runnable)]
[New Thread 5126 (runnable)]
[Switching to Thread 3076 (runnable)]

Breakpoint 1, fft_asmb_sse (k=0, x=0x0, wTB=0x0, d=0x0, d_3=0x0)
    at ac3_srfft_sse.c:221
221     {
(gdb) bt
#0  fft_asmb_sse (k=0, x=0x0, wTB=0x0, d=0x0, d_3=0x0) at ac3_srfft_sse.c:221
#1  0x80b4f73 in module_imdctsse_fft_128p (a=0x0) at ac3_srfft_sse.c:73
(gdb) cont
Continuing.

Program received signal SIGSEGV, Segmentation fault.
0x80b52a9 in fft_asmb_sse (k=134958963, x=0x2, wTB=0x8165720, d=0x8165760, 
    d_3=0x80ce840) at ac3_srfft_sse.c:222
222         __asm__ __volatile__ (

 Is what I get when trying to play *any* DVD disc,  when compiled with
--disable-mmx it works just fine, although the sound tends to skip, badly.

 For the above tracebacks, I specifically compiled with -g aswell, to get a
better feel on what's going on. the 'x' pointer seem to be at fault here,
but I don't have time to spend on this at the moment,  if any other info
is needed, feel free to contact me directly, since I am not registered
to this list.

	bye,
		Marc.

-- 
marc @ corky.net

fingerprint = D1F0 5689 967F B87A 98EB  C64D 256A D6BF 80DE 6D3C

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