fpu state (x87)

Question

I am searching for info about how many values can be considered as part of current fpu state (I mean the values on which floating point code calculations depend on) I know that it would be 3 modes of precission, 4 modes of rounding, about 5 bit flags related to fpu exceptions but what else more? tnx

Answer 1

Check the Intel manuals, chapter 8.

Answer 2

See the documentation of _controlfp() or _control87(). Those are the functions to change the fpu flags. For example on MSDN: https://msdn.microsoft.com/en-us/library/c9676k6h.aspx