[FFmpeg-devel] [BUG avutil] Armv6 crash with AV_RN32

Pavel Pavlov pavel
Wed Mar 3 01:43:53 CET 2010


> > Revision 18601: "ARM asm for AV_RN*(), ARMv6 and later support
> > [...]
> >
> > So, it appears that ldr cannot be used for unaligned reads. Target
> > device is HTC Touch Pro2 (arm1136j-s)
>
> ARM1136 supports unaligned accesses perfectly.  Your OS is misconfigured.


ARM1136 does NOT support unaligned access.
I'm wondering, how is that possible that OS is misconfigured (HTC Touch pro 2, retail unmodified version)? Does that mean that cpu has some sort of control register to disable unaligned access?? Doesn't make sense to me, either it's available or it's not. 

http://www.keil.com/support/man/docs/armasm/armasm_cihdbfje.htm : (In ARMv6T2 and above unaligned access is permitted. In ARMv7 and above unaligned access is available (and is the default))
http://en.wikipedia.org/wiki/ARM_architecture : ARMv6T2 goes from ARM1156T2(F)-S, ARM1136J(F)-S is only ARMv6


To me it means that somebody added code that will crash most of htc phones, HTC been using that ARM1136 for years in most of their models!



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