Fast CopyScreen Routine
void FastCopyScreen(void* src,void* dest) __attribute__((__stkparm__));
void FastCopyScreen_R(register void* src asm("%a0"),register void* dest asm("%a1")) __attribute__((__regparm__(2)));
FastCopyScreen copies a complete screen (3840 bytes == 240x128 pixels) from buffer src
to buffer dest. The implementation is similar to the one used within the actual
grayscale support. You can bet it's really fast.
WARNING: Kevin Kofler (kevin.kofler@chello.at) informed me
that FastCopyScreen will crash your calculator if src points into the archive memory,
for example if you try to copy a screen which is stored in an archived variable. Don't use FastCopyScreen
in this case.
In general, I highly recommend using FastCopyScreen_R instead of memcpy: to date, the PedroM memcpy is extremely
slow.