By most modern architectures you mean 32bit, since you seem to think accessing a 64bit "long" (it's 32bits on windows btw) takes two memory accesses. 32bit arch

By most modern architectures you mean 32bit, since you seem to think accessing a 64bit "long" (it's 32bits on windows btw) takes two memory accesses. 32bit architectures are not "modern"... Maybe you meant unaligned 64bit accesses, which will be 2 reads, but those are pretty cheap since Sandy Bridge or earlier.