History of Berkeley SoftFloat, to Release 3

John R. Hauser
2014 _____

*** CONTENT DONE.

Complete rewrite, funded by the University of California, Berkeley. Major changes included renaming most types and functions, upgrading some algorithms, restructuring the source files, and making SoftFloat into a true library.
Added functions to convert between floating-point and unsigned integers, both 32-bit and 64-bit (uint32_t and uint64_t).
Added functions for fused multiply-add, for all supported floating-point formats except 80-bit double-extended-precision.
Added support for a fifth rounding mode, near_maxMag (round to nearest, with ties to maximum magnitude, away from zero).
Dropped the timesoftfloat program (now part of the Berkeley TestFloat package).

Further improved wording for the legal restrictions on using SoftFloat releases through 2c.

Made minor updates to the documentation, including improved wording for the legal restrictions on using SoftFloat.

Added functions to convert between 64-bit integers (int64) and all supported floating-point formats.
Fixed a bug in all 64-bit-version square root functions except float32_sqrt that caused the result sometimes to be off by 1 unit in the last place (1 ulp) from what it should be. (Bug discovered by Paul Donahue.)
Improved the Makefiles.

Created the 64-bit (bits64) version, adding the floatx80 and float128 formats.
Changed the source directory structure, splitting the sources into a bits32 and a bits64 version. Renamed environment.h to milieu.h to avoid confusion with environment variables.
Fixed a small error that caused float64_round_to_int often to round the wrong way in nearest/even mode when the operand was between 2²⁰ and 2²¹ and halfway between two integers.

Corrected a mistake that caused borderline underflow cases not to raise the underflow flag when they should have. (Problem reported by Doug Priest.)
Added the float_detect_tininess variable to control whether tininess is detected before or after rounding.