Check if FMA/AVX/SSE3 is supported before using it
fully naked main loop in win32 with proper seh directives
win32: more xmm regs to allocate and no need to save them when calling
out
generates direct vmem read & write accesses
trap sigsegv and rewrite using slow path
add w29 to allocatable registers
get rid of literals and use pc-rel branching
minor optimizations and cleanup
This consolidates some of the work done for TARGET_NO_NVMEM and
feat/no-direct-memmap. If nvmem is disabled at compile time or alloc
fails _nvmem_enabled() will return false. Various other fixes
and cleanups all around.