the send asm code is quite ugly atm (pushf & popf to save stereo flag), but the new regression test should ensure we don't break it again if we eventually refactor it
assume songs code it as 1 always; implementations are free to change this during compilation, but this should be a compile time flag / optimization; not a concern of song.
The global pattern table is constructed only during compilation. At this point, we can do also all sorts of optimizations / changes e.g. remove unnecessary releases and reuse patterns if there's a pattern already that could be used.
gopher had fixed this, but we foolishly removed it. reintroducing fix, although this could be optional only for those who really care. ultimate size optimizers could still want to get rid of it.
The working principle is similar as before with x86, but instead of outputting .asm, it outputs .wat. This can be compiled into .wasm by using the wat2wasm assembler.
