HelenOS sources

ISTATE_OFFSET_R25   57 kernel/arch/ppc32/include/arch/istate_struct.h #define ISTATE_OFFSET_R25       0x64
ISTATE_OFFSET_R25   57 uspace/lib/c/arch/ppc32/include/libarch/istate_struct.h #define ISTATE_OFFSET_R25       0x64
HelenOS homepage, sources at GitHub