I suppose you meant to write that: a FMA instruction rounds only once at the end, but both the Multiply and Add instructions also round once each = total two ti

I suppose you meant to write that: a FMA instruction rounds only once at the end, but both the Multiply and Add instructions also round once each = total two times. BTW. Some MIPS processors did have a FMA instruction that did round twice. The compiler was thus able to fuse instructions without the code giving different results. This was deprecated in later versions, however.