This mainly consists of replacing all the pointer arithmatic 'addiu'
instructions with PTR_ADDIU which will handle the differences in pointer
sizes when compiled on 64 bit mips systems.

The header asmdefs.h contains the PTR_ macros which expend to the correct mips
instructions to manipulate registers containing pointers.
Signed-off-by: James Cowgill <james410@cowgill.org.uk>
Reviewed-by: Nedeljko Babic <Nedeljko.Babic@imgtec.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

List of clobbered registers fixed and added where it is lacking.
Signed-off-by: Nedeljko Babic <nbabic@mips.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

__volatile__ can cause problems with some compilers and volatile is a standard keyword.
Found-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

MP3 fixed and floating point decoders are optimized
 for MIPS architecture.
Signed-off-by: Nedeljko Babic <nbabic@mips.com>
Reviewed-by: Vitor Sessak <vitor1001@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>