Berkeley TestFloat History

# History of Berkeley TestFloat, to Release 3e

John R. Hauser
2018 January 20

Releases of Berkeley TestFloat normally parallel those of Berkeley SoftFloat, on which TestFloat is based. Each TestFloat release necessarily incorporates all bug fixes from the corresponding release of SoftFloat.

### Release 3e (2018 January)

- Fixed a problem with the all-in-one `testfloat` program whereby function set `-all1` incorrectly also tested the three-operand fused multiply-add operations.
- Modified the expected behavior of rounding mode `odd` (jamming) when rounding to an integer value (either conversion to an integer format or a ‘`roundToInt`’ function). Previously, for those cases only, rounding mode `odd` was expected to act the same as rounding to minimum magnitude. Now, when rounding to an integer value, the nearest odd integer is expected, consistent with the round-to-odd result of other operations.
- Added options `-checkInvInts` and `-checkAll` to programs `testfloat_ver` and `testfloat`.
- Improved the checking of integer results of invalid operations.

### Release 3d (2017 August)

- When the all-in-one `testfloat` program is compiled to test the C language’s arithmetic, added the ability to test library functions `sqrtf`, `sqrtl`, `fmaf`, `fma`, and `fmal`, which were added to the C Standard in 1999.

### Release 3c (2017 February)

- Added support for testing rounding mode `odd` (jamming).
- Made support for testing 64-bit double-precistion floating-point be subject to macro `FLOAT64` (akin to macros `FLOAT16`, `EXTFLOAT80`, and `FLOAT128` from before).
- Fixed some bugs that caused compilation to fail with certain combinations of option macro settings.
- Corrected the types of two internal variables to be `sig_atomic_t` instead of `bool`.
- Improved the formatting of some error reports (concerning where lines are broken when they exceed 79 characters in length).

### Release 3b (2016 July)

- Added the ability to test the common 16-bit “half-precision” floating-point format.
- Added a `-seed` option to programs `testfloat_gen`, `testfloat`, and `testsoftfloat` for setting the seed for the pseudo-random number generator used to generate test cases.
- Where a specific choice is needed for how tininess is detected on underflow, changed the default to be the detection of tininess after rounding (`-tininessafter`) instead of before rounding (`-tininessbefore`).
- Modified the format of reported discrepancies to show the signs of floating-point values using `+` and `-` characters.
- Documented the use of the `INLINE` macro, and fixed the sources for the case that function inlining is not supported by the C compiler.
- Documented the possible need to define macro `THREAD_LOCAL` to match how the SoftFloat library was built.
- Modified the provided Makefiles to allow some options to be overridden from the `make` command.

### Release 3a (2015 October)

- Replaced the license text supplied by the University of California, Berkeley, and fixed some minor build problems.

### Release 3 (2015 February)

- Complete rewrite, funded by the University of California, Berkeley, and consequently having a different use license than earlier releases. Visible changes included different names for testable functions and command options.
- Reinstated separate programs for generating test cases (`testfloat_ver`) and verifying test results (`testfloat_gen`), as alternatives to the all-in-one `testfloat` program (which remained supported).
- Added support for testing conversions between floating-point and unsigned integers, both 32-bit and 64-bit.
- Added support for testing a fused multiply-add operation, for all testable floating-point formats except 80-bit double-extended-precision.
- Added support for testing a fifth rounding mode, `near_maxMag` (round to nearest, with ties to maximum magnitude, away from zero).
- Added `timesoftfloat` (previously found in the Berkeley SoftFloat package).

### Release 2c (2015 January)

- Fixed mistakes affecting some 64-bit processors.
- Made minor updates to the documentation, including improved wording for the legal restrictions on using TestFloat releases through 2c (not applicable to Release 3 or later).

There was never a Release 2b.

### Release 2a (1998 December)

- Added support for testing conversions between floating-point and 64-bit signed integers.
- Improved the Makefiles.

### Release 2 (1997 June)

- Integrated the generation of test cases and the checking of system results into a single program. (Before they were separate programs, normally joined by explicit command-line pipes.)
- Improved the sequence of test cases.
- Added support for testing 80-bit double-extended-precision and 128-bit quadruple precision.
- Made program output more readable, and added new command arguments.
- Reduced dependence on the quality of the standard `rand` function for generating test cases. (Previously naively expected `rand` to be able to generate good random bits for the entire machine word width.)
- Created `testsoftfloat`, with its own simpler complete software floating-point (“slowfloat”) for comparison purposes.
- Made some changes to the source file structure, including renaming `environment.h` to `milieu.h` (to avoid confusion with environment variables).

### Release 1a (1996 July)

- Added the `-tininessbefore` and `-tininessafter` options to control whether tininess should be detected before or after rounding.

### Release 1 (1996 July)

- Original release.