#11 SSE SIGILL on PIII

[Anonymous]

I get this fault:

[New Thread 1024 (LWP 1740)]
Horizontal size: 320
Vertical size: 240
Frame rate code: 4 = 29.970 fps
Assuming norm NTSC

Encoding MPEG-1 video to /project/mpeg/video.mpg
Sequence header only for first GOP
Search radius: 16
SETTING SSE and EXTENDED MMX for QUANTIZER!
SETTING EXTENDED MMX for MOTION!
SETTING MMX for TRANSFORM!
SETTING EXTENDED MMX for PREDICTION!
Frame rate = 30
Frame 1 P
Program received signal SIGILL, Illegal instruction.
[Switching to Thread 1024 (LWP 1740)]
quant_non_intra_sse (picture=0x808ba60, src=0x4020e010,
dst=0x401d5010,
mquant=2, nonsat_mquant=0x856729c) at
quantize_x86.c:237
237 __asm__ ( "ldmxcsr %0\n" : : "X" (trunc_mxcsr) );

on this cpu:

$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 8
model name : Pentium III (Coppermine)
stepping : 6
cpu MHz : 1004.302
cache size : 256 KB
fdiv_bug : no
hlt_bug : no
sep_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr
pge mca cmov pat pse36 mmx fxsr xmm
bogomips : 1998.85

If I change quantize.c:75: pquant_non_intra =
quant_non_intra
then it runs fine.

ACCEL_X86_MMXEXT is set

Chris

[Andrew Stevens]

Logged In: YES
user_id=50127

Error in SSE detection code. Presence of SSE detected but
not O.S. support for its use. Didn't show 'cos my P-III's
were eng samples(C stepping) which don't SIGILL in this
situation. They merely get corrupt SSE regs ;-)

Bug should be fixed in CVS version.