AuroraMiddleware/glibc
1
0
Fork 0
mirror of https://sourceware.org/git/glibc.git synced 2024-11-08 14:20:07 +00:00
Code Issues Packages Projects Releases Wiki Activity

Clarify math/README.libm-test. Add "How to read the test output."

Browse Source
This commit is contained in:
Martin Sebor 2015-01-28 21:07:01 -07:00
parent 06991eb816
commit 527de9e4e3
2 changed files with 69 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
ChangeLog
View File

@ -1,3 +1,7 @@
2015-01-28 Martin Sebor <msebor@redhat.com>
* math/README.libm-test: Clarify. Add "How to read the test output."
2015-01-28 Chris Metcalf <cmetcalf@ezchip.com>
* sysdeps/tile/tilegx/bits/atomic.h [!_LP64] (__HAVE_64B_ATOMICS):

77
math/README.libm-test
View File

@ -21,20 +21,45 @@ NaNs and minus zero), some more or less random values are tested.
Files that are part of libm-test
================================
The main file is "libm-test.inc". It is platform and floating point
format independent. The file must be preprocessed by the Perl script
"gen-libm-test.pl". The results are "libm-test.c" and a file
"libm-test-ulps.h" with platform specific deltas.
The main file is "libm-test.inc". It is independent of the target
platform and the specific real floating type and format and contains
placeholder test "templates" for math functions defined in libm.
The file, along with a generated file named "auto-libm-test-out",
is preprocessed by the Perl script "gen-libm-test.pl" to expand
the templates and produce a set of test cases for each math function
that are specific to the target platform but still independent of
the real floating type. The results of the processing are
"libm-test.c" and a file "libm-test-ulps.h" with platform specific
deltas by which the actual math function results may deviate from
the expected results and still be considered correct.
The test drivers test-double.c, test-float.c, test-ldouble.c test the
normal double, float and long double implementation of libm. The test
drivers with an i in it (test-idouble.c, test-ifloat.c,
test-ildoubl.c) test the corresponding inline functions (where
available - otherwise they also test the real functions in libm).
The test drivers "test-double.c", "test-float.c", and "test-ldouble.c"
test the normal double, float and long double implementation of libm.
The test drivers with an 'i' in their name ("test-idouble.c",
"test-ifloat.c", and "test-ildoubl.c") test the corresponding inline
functions (where available - otherwise they also test the real
functions in libm). Each driver selects the desired real floating
type to exercise the math functions to test with (float, double, or
long double) by defining a small set of macros just before including
the generic "libm-test.c" file. Each driver also either defines or
undefines the __NO_MATH_INLINES macro just before including
"libm-test.c" to select either the real or inline functions,
respectively. Each driver is compiled into a single executable test
program with the corresponding name.
"gen-libm-test.pl" needs a platform specific files with ULPs (Units of
Last Precision). The file is called "libm-test-ulps" and lives in
platform specific sysdep directory.
As mentioned above, the "gen-libm-test.pl" script looks for a file
named "libm-test-ulps" in the platform specific sysdep directory (or
its fpu or nofpu subdirectory) and for each variant (real floating
type and rounding mode) of every tested function reads from it the
maximum difference expressed as Units of Least Precision (ULP) the
actual result of the function may deviate from the expected result
before it's considered incorrect.
The "auto-libm-test-out" file contains sets of test cases to exercise,
the conditions under which to exercise each, and the expected results.
The file is generated by the "gen-auto-libm-tests" program from the
"auto-libm-test-in" file. See the comments in gen-auto-libm-tests.c
for details about the content and format of the -in and -out files.
How can I generate "libm-test-ulps"?
====================================
@ -101,3 +126,31 @@ The accepted parameter types are:
- "L" for long long int.
- "F" for the address of a FLOAT (only as input parameter)
- "I" for the address of an int (only as input parameter)
How to read the test output
===========================
Running each test on its own at the default level of verbosity will
print on stdout a line describing the implementation of math functions
exercised by the test (float, double, or long double), along with
whether the inline set has been selected, regardless of whether or
not any inline functions actually exist. This is then followed by
the details of test failures (if any). The output concludes by
a summary listing the number of test cases exercised and the number
of test failures uncovered.
For each test failure (and for each test case at higher levels of
verbosity), the output contains the name of the function under test
and its arguments or conditions that triggered the failure. Note
that the name of the function in the output need not correspond
exactly to the name of the math function actually invoked. For example,
the output will refer to the "acos" function even if the actual function
under test is acosf (for the float version) or acosl (for the long
double version). Also note that the function arguments may be shown
in either the decimal or the hexadecimal floating point format which
may or may not correspond to the format used in the auto-libm-test-in
file. Besides the name of the function, for each test failure the
output contains the actual and expected results and the difference
between the two, printed in both the decimal and hexadecimal
floating point format, and the ULP and maximum ULP for the test
case.