Memmap: Remove pointer casts

[lioncash]

Gets rid of ugly casts, and also silences some ubsan asserts

[degasus]

I'm not sure, will this generate an as good assembly? This function is called quite often :/

[lioncash]

Yes it will (https://goo.gl/50jAT7). memcpy is typically implemented as an intrinsic in compilers. Also, the previous code is technically undefined behavior (misaligned pointer dereferencing)

[dolphin-emu-bot]

FifoCI detected that this change impacts graphical rendering. Here are the behavior differences detected by the system:

• xenoblade-menu on ogl-lin-nv: diff

_{^{automated-fifoci-reporter}}

[comex]

For the record, I just verified using that site that both gcc and clang do the right thing even at -O0 (which is fairly important - when I develop I build at -O0, for example). Does anyone want to check MSVC?

[degasus]

@comex Are you looking for a correct implementation, or a fast one? Personally, I don't care about the optimizations done at -O0

[comex]

A fast one, though I guess a real call to memcpy probably wouldn't show up anyway among all the other unoptimized crap. Never mind me.

[phire]

I don't really like compiling at -O0. Would rather read the -O2 assembly.