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diff --git a/tools/test/testfloat/testfloat-source.txt b/tools/test/testfloat/testfloat-source.txt deleted file mode 100644 index 8c5efa9136f1..000000000000 --- a/tools/test/testfloat/testfloat-source.txt +++ /dev/null @@ -1,444 +0,0 @@ - -TestFloat Release 2a Source Documentation - -John R. Hauser -1998 December 16 - - -------------------------------------------------------------------------------- -Introduction - -TestFloat is a program for testing that a floating-point implementation -conforms to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. -All standard operations supported by the system can be tested, except for -conversions to and from decimal. Any of the following machine formats can -be tested: single precision, double precision, extended double precision, -and/or quadruple precision. Testing extended double-precision or quadruple- -precision formats requires a C compiler that supports 64-bit integer -arithmetic. - -This document gives information needed for compiling and/or porting -TestFloat. - -The source code for TestFloat is intended to be relatively machine- -independent. TestFloat is written in C, and should be compilable using -any ISO/ANSI C compiler. At the time of this writing, the program has -been successfully compiled using the GNU C Compiler (`gcc') for several -platforms. Because ISO/ANSI C does not provide access to some features -of IEC/IEEE floating-point such as the exception flags, porting TestFloat -unfortunately involves some machine-dependent coding. - -TestFloat depends on SoftFloat, which is a software implementation of -floating-point that conforms to the IEC/IEEE Standard. SoftFloat is not -included with the TestFloat sources. It can be obtained from the Web -page `http://HTTP.CS.Berkeley.EDU/~jhauser/arithmetic/SoftFloat.html'. - -In addition to a program for testing a machine's floating-point, the -TestFloat package includes a variant for testing SoftFloat called -`testsoftfloat'. The sources for both programs are intermixed, and both are -described here. - -The first release of TestFloat (Release 1) was called _FloatTest_. The old -name has been obsolete for some time. - - -------------------------------------------------------------------------------- -Limitations - -TestFloat as written requires an ISO/ANSI-style C compiler. No attempt has -been made to accommodate compilers that are not ISO-conformant. Older ``K&R- -style'' compilers are not adequate for compiling TestFloat. All testing I -have done so far has been with the GNU C Compiler. Compilation with other -compilers should be possible but has not been tested. - -The TestFloat sources assume that source code file names can be longer than -8 characters. In order to compile under an MS-DOS-style system, many of the -source files will need to be renamed, and the source and makefiles edited -appropriately. Once compiled, the TestFloat program does not depend on the -existence of long file names. - -The underlying machine is assumed to be binary with a word size that is a -power of 2. Bytes are 8 bits. Testing of extended double-precision and -quadruple-precision formats depends on the C compiler implementing a 64-bit -integer type. If the largest integer type supported by the C compiler is -32 bits, only single- and double-precision operations can be tested. - - -------------------------------------------------------------------------------- -Contents - - Introduction - Limitations - Contents - Legal Notice - TestFloat Source Directory Structure - Target-Independent Modules - Target-Specific Modules - Target-Specific Header Files - processors/*.h - testfloat/*/milieu.h - Target-Specific Floating-Point Subroutines - Steps to Creating the TestFloat Executables - Improving the Random Number Generator - Contact Information - - - -------------------------------------------------------------------------------- -Legal Notice - -TestFloat was written by John R. Hauser. - -THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort -has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT -TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO -PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY -AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE. - - -------------------------------------------------------------------------------- -TestFloat Source Directory Structure - -Because TestFloat is targeted to multiple platforms, its source code -is slightly scattered between target-specific and target-independent -directories and files. The directory structure is as follows: - - processors - testfloat - templates - 386-Win32-gcc - SPARC-Solaris-gcc - -The two topmost directories and their contents are: - - testfloat - Most of the source code needed for TestFloat. - processors - Target-specific header files that are not specific to - TestFloat. - -Within the `testfloat' directory are subdirectories for each of the -targeted platforms. The TestFloat source code is distributed with targets -`386-Win32-gcc' and `SPARC-Solaris-gcc' (and perhaps others) already -prepared. These can be used as examples for porting to new targets. Source -files that are not within these target-specific subdirectories are intended -to be target-independent. - -The naming convention used for the target-specific directories is -`<processor>-<executable-type>-<compiler>'. The names of the supplied -target directories should be interpreted as follows: - - <processor>: - 386 - Intel 386-compatible processor. - SPARC - SPARC processor (as used by Sun machines). - <executable-type>: - Win32 - Microsoft Win32 executable. - Solaris - Sun Solaris executable. - <compiler>: - gcc - GNU C Compiler. - -You do not need to maintain this convention if you do not want to. - -Alongside the supplied target-specific directories there is a `templates' -directory containing a set of ``generic'' target-specific source files. -A new target directory can be created by copying the `templates' directory -and editing the files inside. (Complete instructions for porting TestFloat -to a new target are in the section _Steps_to_Creating_the_TestFloat_ -_Executables_.) Note that the `templates' directory will not work as a -target directory without some editing. To avoid confusion, it would be wise -to refrain from editing the files inside `templates' directly. - -In addition to the distributed sources, TestFloat depends on the existence -of an appropriately-compiled SoftFloat binary and the corresponding header -file `softfloat.h'. SoftFloat is not included with the TestFloat sources. -It can be obtained from the Web page `http://HTTP.CS.Berkeley.EDU/~jhauser/ -arithmetic/SoftFloat.html'. - -As distributed, the makefiles for TestFloat assume the existence of three -sibling directories: - - processors - softfloat - testfloat - -Only the `processors' and `testfloat' directories are included in the -TestFloat package. The `softfloat' directory is assumed to contain a -target-specific subdirectory within which the SoftFloat header file and -compiled binary can be found. (See the source documentation accompanying -SoftFloat.) The `processors' directory distributed with TestFloat is -intended to be identical to that included with the SoftFloat source. - -These are the defaults, but other organizations of the sources are possible. -The TestFloat makefiles and `milieu.h' files (see below) are easily edited -to accommodate other arrangements. - - -------------------------------------------------------------------------------- -Target-Independent Modules - -The TestFloat program is composed of a number of modules, some target- -specific and some target-independent. The target-independent modules are as -follows: - --- The `fail' module provides a common routine for writing an error message - and aborting. - --- The `random' module generates random integer values. - --- The `writeHex' module defines routines for writing the various types in - the hexadecimal form used by TestFloat. - --- The `testCases' module generates test cases for the various types. - --- The `testLoops' module contains various routines for exercising two - implementations of a function and reporting any differences observed. - --- The `slowfloat' module provides the simple floating-point implementation - used by `testsoftfloat' for comparing against SoftFloat. The heart - of `slowfloat' is found in either `slowfloat-32' or `slowfloat-64', - depending on whether the `BITS64' macro is defined. - --- The `systfloat' module gives a SoftFloat-like interface to the machine's - floating-point. - --- The `testFunction' module implements `testfloat's main loop for testing a - function for all of the relevant rounding modes and rounding precisions. - (The `testsoftfloat' program contains its own version of this code.) - --- The `testfloat' and `testsoftfloat' modules are the main modules for the - `testfloat' and `testsoftfloat' programs. - -Except possibly for `systfloat', these modules should not need to be -modified. - -The `systfloat' module uses the floating-point operations of the C language -to access a machine's floating-point. Unfortunately, some IEC/IEEE -floating-point operations are not accessible within ISO/ANSI C. The -following machine functions cannot be tested unless an alternate `systfloat' -module is provided: - - <float>_to_int32 (rounded according to rounding mode) - <float>_to_int64 (rounded according to rounding mode) - <float>_round_to_int - <float>_rem - <float>_sqrt, except float64_sqrt - <float>_eq_signaling - <float>_le_quiet - <float>_lt_quiet - -The `-list' option to `testfloat' will show the operations the program is -prepared to test. The section _Target-Specific_Floating-Point_Subroutines_ -later in this document explains how to create a target-specific `systfloat' -module to change the set of testable functions. - - -------------------------------------------------------------------------------- -Target-Specific Modules - -No target-specific modules are needed for `testsoftfloat'. - -The `testfloat' program uses two target-specific modules: - --- The `systmodes' module defines functions for setting the modes - controlling the system's floating-point, including the rounding mode and - the rounding precision for extended double precision. - --- The `systflags' module provides a function for clearing and examining the - system's floating-point exception flags. - -These modules must be supplied for each target. They can be implemented in -any way desired, so long as all is reflected in the target's makefile. For -the targets that come with the distributed source, each of these modules is -implemented as a single assembly language or C language source file. - - -------------------------------------------------------------------------------- -Target-Specific Header Files - -The purpose of the two target-specific header files is detailed below. -In the following, the `*' symbol is used in place of the name of a specific -target, such as `386-Win32-gcc' or `SPARC-Solaris-gcc', or in place of some -other text as explained below. - -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -processors/*.h - -The target-specific `processors' header file defines integer types -of various sizes, and also defines certain C preprocessor macros that -characterize the target. The two examples supplied are `386-gcc.h' and -`SPARC-gcc.h'. The naming convention used for processor header files is -`<processor>-<compiler>.h'. The `processors' header file used to compile -TestFloat should be the same as that used to compile SoftFloat. - -If 64-bit integers are supported by the compiler, the macro name `BITS64' -should be defined here along with the corresponding 64-bit integer -types. In addition, the function-like macro `LIT64' must be defined for -constructing 64-bit integer literals (constants). The `LIT64' macro is used -consistently in the TestFloat code to annotate 64-bit literals. - -If an inlining attribute (such as an `inline' keyword) is provided by the -compiler, the macro `INLINE' should be defined to the appropriate keyword. -If not, `INLINE' can be set to the keyword `static'. The `INLINE' macro -appears in the TestFloat source code before every function that should be -inlined by the compiler. - -For maximum flexibility, the TestFloat source files do not include the -`processors' header file directly; rather, this file is included by the -target-specific `milieu.h' header, and `milieu.h' is included by the source -files. - -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -testfloat/*/milieu.h - -The `milieu.h' header file provides declarations that are needed to -compile TestFloat. In particular, it is through this header file that -the appropriate `processors' header is included to characterize the target -processor. In addition, deviations from ISO/ANSI C by the compiler (such as -names not properly declared in system header files) are corrected in this -header if possible. - -If the preprocessor macro `BITS64' is defined in the `processors' header -file but only the 32-bit version of SoftFloat is actually used, the `BITS64' -macro should be undefined here after the `processors' header has defined it. - -If the C compiler implements the `long double' floating-point type of C -as extended double precision, then `LONG_DOUBLE_IS_FLOATX80' should be -defined here. Alternatively, if the C `long double' type is implemented as -quadruple precision, `LONG_DOUBLE_IS_FLOAT128' should be defined. At most -one of these macros should be defined. A C compiler is allowed to implement -`long double' the same as `double', in which case neither of these macros -should be defined. - -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -------------------------------------------------------------------------------- -Target-Specific Floating-Point Subroutines - -This section applies only to `testfloat' and not to `testsoftfloat'. - -By default, TestFloat tests a machine's floating-point by testing the -floating-point operations of the C language. Unfortunately, some IEC/IEEE -floating-point operations are not defined within ISO/ANSI C. If a machine -implements such ``non-C'' operations, target-specific subroutines for -the operations can be supplied to allow TestFloat to test these machine -features. Typically, such subroutines will need to be written in assembly -language, although equivalent functions can sometimes be found among the -system's software libraries. - -The following machine functions cannot be tested by TestFloat unless target- -specific subroutines are supplied for them: - - <float>_to_int32 (rounded according to rounding mode) - <float>_to_int64 (rounded according to rounding mode) - <float>_round_to_int - <float>_rem - <float>_sqrt, except float64_sqrt - <float>_eq_signaling - <float>_le_quiet - <float>_lt_quiet - -In addition to these, none of the `floatx80' functions can be tested by -default if the C `long double' type is something other than extended double -precision; and likewise, none of the `float128' functions can be tested by -default if `long double' is not quadruple precision. Since `long double' -cannot be both extended double precision and quadruple precision at the -same time, at least one of these types cannot be tested by TestFloat without -appropriate subroutines being supplied for that type. (On the other hand, -few systems implement _both_ extended double-precision and quadruple- -precision floating-point; and unless a system does implement both, it does -not need both tested.) - -Note that the `-list' option to `testfloat' will show the operations -TestFloat is prepared to test. - -TestFloat's `systfloat' module supplies the system version of the functions -to be tested. The names of the `systfloat' subroutines are the same as the -function names used as arguments to the `testfloat' command but with `syst_' -prefixed--thus, for example, `syst_float32_add' and `syst_int32_to_float32'. -The default `systfloat' module maps these system functions to the standard -C operations; so `syst_float32_add', for example, is implemented using the -C `+' operation for the single-precision `float' type. For each system -function supplied by `systfloat', a corresponding `SYST_<function>' -preprocessor macro is defined in `systfloat.h' to indicate that the function -exists to be tested (e.g., `SYST_FLOAT32_ADD'). The `systfloat.h' header -file also declares function prototypes for the `systfloat' functions. - -(The `systfloat.h' file that comes with the TestFloat package declares -prototypes for all of the possible `systfloat' functions, whether defined in -`systfloat' or not. There is no penalty for declaring a function prototype -that is never used.) - -A target-specific version of the `systfloat' module can easily be created to -replace the generic one. This in fact has been done for the example targets -`386-Win32-gcc' and `SPARC-Solaris-gcc'. For each target, an assembly -language `systfloat.S' has been created in the target directory along with -a corresponding `systfloat.h' header file defining the `SYST_<function>' -macros for the functions implemented. The makefiles of the targets have -been edited to use these target-specific versions of `systfloat' rather than -the generic one. - -The `systfloat' modules of the example targets have been written entirely -in assembly language in order to bypass any peculiarities of the C compiler. -Although this is probably a good idea, it is certainly not required. - - -------------------------------------------------------------------------------- -Steps to Creating the TestFloat Executables - -Porting and/or compiling TestFloat involves the following steps: - -1. Port SoftFloat and create a SoftFloat binary. (Refer to the - documentation accompanying SoftFloat.) - -2. If one does not already exist, create an appropriate target-specific - subdirectory under `testfloat' by copying the given `templates' - directory. The remaining steps occur within the target-specific - subdirectory. - -3. Edit the files `milieu.h' and `Makefile' to reflect the current - environment. - -4. Make `testsoftfloat' by executing `make testsoftfloat' (or `make - testsoftfloat.exe', or whatever the `testsoftfloat' executable is - called). Verify that SoftFloat is working correctly by testing it with - `testsoftfloat'. - -If you only wanted `testsoftfloat', you are done. The steps for `testfloat' -continue: - -5. In the target-specific subdirectory, implement the `systmodes' and - `systflags' modules. (The `syst_float_set_rounding_precision' function - need not do anything if the system does not support extended double - precision.) - -6. If the target machine supports standard floating-point functions that are - not accessible within ISO/ANSI C, or if the C compiler cannot be trusted - to use the machine's floating-point directly, create a target-specific - `systfloat' module. - -7. In the target-specific subdirectory, execute `make'. - - -------------------------------------------------------------------------------- -Improving the Random Number Generator - -If you are serious about using TestFloat for testing floating-point, you -should consider replacing the supplied `random.c' with a better target- -specific one. The standard C `rand' function is rather poor on some -systems, and consequently `random.c' has been written to assume very little -about the quality of `rand'. As a result, the `rand' function is called -more frequently than it might need to be, shortening the time before -the random number generator repeats, and possibly wasting time as well. -If `rand' is better on your system, or if another better random number -generator is available (such as `rand48' on most Unix systems), TestFloat -can be improved by overriding the given `random.c' with a target-specific -one. - - -------------------------------------------------------------------------------- -Contact Information - -At the time of this writing, the most up-to-date information about -TestFloat and the latest release can be found at the Web page `http:// -HTTP.CS.Berkeley.EDU/~jhauser/arithmetic/TestFloat.html'. - - |