xmalloc_aligned
tls_block = xmalloc_aligned(tls_block_size, maxalign, 0);
tls_block = xmalloc_aligned(size, ralign, 0 /* XXX */);
p = xmalloc_aligned(obj->tlssize, obj->tlsalign, obj->tlspoffset);
void *xmalloc_aligned(size_t size, size_t align, size_t offset);