Intel ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS MANUAL VOLUME 1 REV 2.3 Manual page 119

• The NaTVal is a natural extension of the IEEE concept of NaNs. It is used to support
speculative execution.
• Flush-to-Zero mode is an industry standard addition.
• The minimum and maximum instructions allow the efficient execution of the
common Fortran Intrinsic Functions: MIN(), MAX(), AMIN(), AMAX(); and C
language idioms such as a<b?a:b.
• All mixed precision operations are allowed. The IEEE standard suggests that
implementations allow lower precision operands to produce higher precision
results; this is supported. The IEEE standard also suggests that implementations
not allow higher precision operands to produce lower precision results; this
suggestion is not followed. When computations with higher precision operands
produce values beyond the destination precision range, the information provided in
the ISR.code allows the true result to be unambiguously determined by software.
The correct wrapping count and the appropriate bias amount can also be computed.
• An IEEE style quad-precision real type that is supported in software.
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Volume 1, Part 1: Floating-point Programming Model