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rounding mode

The rule the processor uses to pick a representable float when the exact answer falls between two of them.

IEEE 754 defines round-to-nearest-ties-to-even (the default), round toward zero, toward +inf and toward -inf (plus ties-away for decimal); C++ exposes them through , and x86 holds the current mode in MXCSR.

See also

floating-point infinity IEEE 754
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