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I am looking for a reference implementation of IEEE-754 operations. Is there such a thing?
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Inexact The “real” result of a computation cannot be exactly represented by a floating-point number. The silent response is to round the number, which is a behaviour that the vast majority of programs using floating-point numbers rely upon. However, rounding has to be correctly taking into account for sound analysis.
The IEEE-754 standard describes floating-point formats, a way to represent real numbers in hardware. There are at least five internal formats for floating-point numbers that are representable in hardware targeted by the MSVC compiler. The compiler only uses two of them.
IEEE developed the IEEE 754 floating-point standard. This standard defines set formats and operation modes. All computers conforming to this standard would always calculate the same result for the same computation. This standard does not specify arithmetic procedures and hardware to be used to perform computations.
A signed 32-bit integer variable has a maximum value of 231 − 1 = 2,147,483,647, whereas an IEEE 754 32-bit base-2 floating-point variable has a maximum value of (2 − 2−23) × 2127 ≈ 3.4028235 × 1038.
I believe the C libraries SoftFloat and fdlibm are suitable for what you are looking for. Others include Linux (GNU libc, glibc) or *BSD libc's math functions. Finally, CRlibm should also be of interest to you.
Ulrich Drepper has a interesting look at different math libraries, that might be also worth reading through.
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I must disappoint you: There is practically none.
While technically there are IEEE-754 compliant systems because they do not implement non-required features described in the standard, a reference implementation allowing
does not exist in the standard languages. This causes recurring woes of William Kahan, the main force behind the standard and its adaption on the Intel processors.
I don't know if there are some esoteric languages which do support them, but I can rule out Java, C#, C++, Fortran.
EDIT: While there is a lack of compiler support, I advise Hausers SoftFloat implementation given by mctylr. Hauser knows what he is doing.
http://portal.acm.org/citation.cfm?id=227699.227701&coll=portal&dl=ACM&CFID=77938829&CFTOKEN=18578907
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A rather confusing question; in C++ it is assumed this sort of detail is taken care of by the hardware or the compiler. So, in C++ floating-point addition would be
float a = 1.0;
float b = 2.0;
float c = a + b;
I'm sure this is not what you actually meant; perhaps you'd benefit from this page which tries to emulate IEEE-754-compliant hardware in javascript?
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