Re: Using VC for change descriptions

[Joseph Myers]

On Sun, 7 Jan 2018, Richard Stallman wrote:

>   > There are four paragraphs of human-level explanation of that change as a 
>   > whole in the commit message (glibc commit 
>   > 92061bb033f093cca76e31745cac14c43a1fb29b, "Run libm tests separately for 
>   > each function.").
> 
> I don't know what text is to be found there -- it is too inconvenient
> for me to look.  Are you talking about the text quoted above, or some
> other text?  Would you please show us?
> 
>   > I don't think the 370-line ChangeLog entry adds 
>   > anything useful
> 
> Maybe it doesn't, but could you show me what it says?
> 
> Also, what would you suggest writing instead?

Here is the log for that commit, excluding the ChangeLog entry.  I
believe this log provides everything useful for someone looking at the
change and that if more details are desired, this log and the diffs of
the commit itself are fully sufficient without needing anything
written in ChangeLog format.

commit 92061bb033f093cca76e31745cac14c43a1fb29b
Author: Joseph Myers <address@hidden>
Date:   Fri Feb 24 00:51:45 2017 +0000

    Run libm tests separately for each function.
    
    At present, libm tests for each function get built into a single
    executable (for each floating point type, for each of normal / inline
    / finite-math-only functions, plus vector variants) and run together,
    resulting in a single PASS or FAIL (for each of those nine variants
    plus vector variants).  Building this executable involves reading
    over 50 MB of libm-test-*.c sources.
    
    This patch arranges for tests of each function to be run separately
    from the makefiles instead.  There are 121 functions being tested for
    each (type, variant pair) (actually 126, but run as 121 from the
    Makefile because each of the pairs (exp10, pow10), (isfinite, finite),
    (lgamma, gamma), (remainder, drem), (scalbn, ldexp), shares a table of
    test results and so is run together), so 1089 separate tests run from
    the Makefile, plus 48 vector tests on x86_64 (six functions for eight
    vector variants).  Each test only involves a libm-test-<func>.c file
    of no more than about 4 MB, rather than all such files taking about 50
    MB.  With tests run separately, test summaries will indicate which
    functions actually have problems (of course, those problems may just
    be out-of-date libm-test-ulps files if the file hasn't been updated
    for the architecture in question recently).
    
    All the .c files for the 1089+48 tests are generated automatically
    from the Makefiles.  Various checked-in boilerplate .c files are
    removed as no longer needed.  CFLAGS definitions for the different
    kinds of tests are generated using makefile iterators to apply
    target-specific variable settings.  libm-have-vector-test.h is no
    longer needed; the list of functions to test for each vector type is
    now in the sysdeps Makefile.
    
    This should reduce the amount of boilerplate needed for float128
    testing support; test-float128.h will still be needed, but not various
    .c files or Makefile CFLAGS definitions.  The logic for creating
    dependencies on libm-test-support-*.o files should also render
    <https://sourceware.org/ml/libc-alpha/2017-02/msg00279.html>
    unnecessary.
    
    Tested for x86_64 and x86.

Here is the ChangeLog entry itself, which I don't think is useful given 
the above description and the availability of the commit diffs.

2017-02-24  Joseph Myers  <address@hidden>

        * math/Makefile (libm-tests-generated): Remove variable.
        (libm-tests-base-normal): New variable.
        (libm-tests-base-finite): Likewise.
        (libm-tests-base-inline): Likewise.
        (libm-tests-base): Likewise.
        (libm-tests-normal): Likewise.
        (libm-tests-finite): Likewise.
        (libm-tests-inline): Likewise.
        (libm-tests-vector): Likewise.
        (libm-tests): Define in terms of these new variables.
        (libm-tests-for-type): New variable.
        (libm-tests.o): Move definition.
        (tests): Move addition of $(libm-tests).
        (generated): Update for new and removed libm test files.
        ($(objpfx)libm-test.c): Remove target.
        ($(objpfx)libm-have-vector-test.h): Likewise.
        (CFLAGS-test-double-vlen2.c): Remove variable.
        (CFLAGS-test-double-vlen4.c): Likewise.
        (CFLAGS-test-double-vlen8.c): Likewise.
        (CFLAGS-test-float-vlen4.c): Likewise.
        (CFLAGS-test-float-vlen8.c): Likewise.
        (CFLAGS-test-float-vlen16.c): Likewise.
        (CFLAGS-test-float.c): Likewise.
        (CFLAGS-test-float-finite.c): Likewise.
        (CFLAGS-libm-test-support-float.c): Likewise.
        (CFLAGS-test-double.c): Likewise.
        (CFLAGS-test-double-finite.c): Likewise.
        (CFLAGS-libm-test-support-double.c): Likewise.
        (CFLAGS-test-ldouble.c): Likewise.
        (CFLAGS-test-ldouble-finite.c): Likewise.
        (CFLAGS-libm-test-support-ldouble.c): Likewise.
        (libm-test-inline-cflags): New variable.
        (CFLAGS-test-ifloat.c): Remove variable.
        (CFLAGS-test-idouble.c): Likewise.
        (CFLAGS-test-ildouble.c): Likewise.
        ($(addprefix $(objpfx), $(libm-tests.o))): Move target and update
        dependencies.
        ($(foreach t,$(libm-tests-normal),$(objpfx)$(t).c)): New rule.
        ($(foreach t,$(libm-tests-finite),$(objpfx)$(t).c)): Likewise.
        ($(foreach t,$(libm-tests-inline),$(objpfx)$(t).c)): Likewise.
        ($(foreach t,$(libm-tests-vector),$(objpfx)$(t).c)): Likewise.
        ($(foreach t,$(types),$(objpfx)libm-test-support-$(t).c)):
        Likewise.
        (dependencies on libm-test-support-*.o): Remove.
        ($(foreach f,$(libm-test-funcs-all),$(objpfx)$(o)-$(f).o)): New
        rules using iterators.
        ($(addprefix $(objpfx),$(call libm-tests-for-type,$(o)))):
        Likewise.
        ($(objpfx)libm-test-support-$(o).o): Likewise.
        ($(addprefix $(objpfx),$(filter-out $(tests-static)
        $(libm-vec-tests),$(tests)))): Filter out $(libm-tests-vector)
        instead.
        ($(addprefix $(objpfx), $(libm-vec-tests))): Use iterator to
        define rule instead.
        * math/README.libm-test: Update.
        * math/libm-test-acos.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-acosh.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-asin.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-asinh.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-atan.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-atan2.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-atanh.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-cabs.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-cacos.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-cacosh.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-canonicalize.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-carg.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-casin.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-casinh.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-catan.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-catanh.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-cbrt.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-ccos.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-ccosh.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-ceil.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-cexp.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-cimag.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-clog.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-clog10.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-conj.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-copysign.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-cos.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-cosh.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-cpow.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-cproj.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-creal.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-csin.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-csinh.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-csqrt.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-ctan.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-ctanh.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-erf.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-erfc.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-exp.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-exp10.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-exp2.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-expm1.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-fabs.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-fdim.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-floor.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-fma.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-fmax.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-fmaxmag.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-fmin.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-fminmag.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-fmod.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-fpclassify.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-frexp.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-fromfp.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-fromfpx.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-getpayload.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-hypot.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-ilogb.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-iscanonical.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-iseqsig.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-isfinite.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-isgreater.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-isgreaterequal.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-isinf.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-isless.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-islessequal.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-islessgreater.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-isnan.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-isnormal.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-issignaling.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-issubnormal.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-isunordered.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-iszero.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-j0.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-j1.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-jn.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-lgamma.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-llogb.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-llrint.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-llround.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-log.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-log10.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-log1p.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-log2.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-logb.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-lrint.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-lround.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-modf.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-nearbyint.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-nextafter.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-nextdown.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-nexttoward.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-nextup.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-pow.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-remainder.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-remquo.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-rint.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-round.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-roundeven.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-scalb.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-scalbln.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-scalbn.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-setpayload.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-setpayloadsig.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-signbit.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-significand.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-sin.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-sincos.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-sinh.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-sqrt.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-tan.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-tanh.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-tgamma.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-totalorder.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-totalordermag.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-trunc.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-ufromfp.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-ufromfpx.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-y0.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-y1.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-yn.inc: Include libm-test-driver.c.
        (do_test): New function.
        * math/libm-test-driver.c: Do not include libm-have-vector-test.h.
        (HAVE_VECTOR): Remove macro.
        (START): Do not call HAVE_VECTOR.
        * math/test-double-vlen2.h (FUNC_TEST): Remove macro.
        * math/test-double-vlen4.h (FUNC_TEST): Remove macro.
        * math/test-double-vlen8.h (FUNC_TEST): Remove macro.
        * math/test-float-vlen16.h (FUNC_TEST): Remove macro.
        * math/test-float-vlen4.h (FUNC_TEST): Remove macro.
        * math/test-float-vlen8.h (FUNC_TEST): Remove macro.
        * math/test-math-vector.h (FUNC_TEST): New macro.
        (WRAPPER_DECL): Rename to WRAPPER_DECL_f.
        * sysdeps/x86_64/fpu/Makefile (double-vlen2-funcs): New variable.
        (double-vlen4-funcs): Likewise.
        (double-vlen4-avx2-funcs): Likewise.
        (double-vlen8-funcs): Likewise.
        (float-vlen4-funcs): Likewise.
        (float-vlen8-funcs): Likewise.
        (float-vlen8-avx2-funcs): Likewise.
        (float-vlen16-funcs): Likewise.
        (CFLAGS-test-double-vlen4-avx2.c): Remove variable.
        (CFLAGS-test-float-vlen8-avx2.c): Likewise.
        * sysdeps/x86_64/fpu/test-double-vlen4.h (TEST_VECTOR_cos): Remove
        macro.
        (TEST_VECTOR_sin): Likewise.
        (TEST_VECTOR_sincos): Likewise.
        (TEST_VECTOR_log): Likewise.
        (TEST_VECTOR_exp): Likewise.
        (TEST_VECTOR_pow): Likewise.
        * sysdeps/x86_64/fpu/test-double-vlen8.h (TEST_VECTOR_cos):
        Likewise.
        (TEST_VECTOR_sin): Likewise.
        (TEST_VECTOR_sincos): Likewise.
        (TEST_VECTOR_log): Likewise.
        (TEST_VECTOR_exp): Likewise.
        (TEST_VECTOR_pow): Likewise.
        * sysdeps/x86_64/fpu/test-float-vlen16.h (TEST_VECTOR_cosf):
        Likewise.
        (TEST_VECTOR_sinf): Likewise.
        (TEST_VECTOR_sincosf): Likewise.
        (TEST_VECTOR_logf): Likewise.
        (TEST_VECTOR_expf): Likewise.
        (TEST_VECTOR_powf): Likewise.
        * sysdeps/x86_64/fpu/test-float-vlen8.h (TEST_VECTOR_cosf):
        Likewise.
        (TEST_VECTOR_sinf): Likewise.
        (TEST_VECTOR_sincosf): Likewise.
        (TEST_VECTOR_logf): Likewise.
        (TEST_VECTOR_expf): Likewise.
        (TEST_VECTOR_powf): Likewise.
        * math/gen-libm-have-vector-test.sh: Remove file.
        * math/libm-test.inc: Likewise.
        * math/libm-test-support-double.c: Likewise.
        * math/libm-test-support-float.c: Likewise.
        * math/libm-test-support-ldouble.c: Likewise.
        * math/test-double-finite.c: Likewise.: Likewise.
        * math/test-double.c: Likewise.
        * math/test-float-finite.c: Likewise.
        * math/test-float.c: Likewise.
        * math/test-idouble.c: Likewise.
        * math/test-ifloat.c: Likewise.
        * math/test-ildouble.c: Likewise.
        * math/test-ldouble-finite.c: Likewise.
        * math/test-ldouble.c: Likewise.
        * sysdeps/x86_64/fpu/test-double-vlen2.c: Likewise.
        * sysdeps/x86_64/fpu/test-double-vlen2.h: Likewise.
        * sysdeps/x86_64/fpu/test-double-vlen4-avx2.c: Likewise.
        * sysdeps/x86_64/fpu/test-double-vlen4.c: Likewise.
        * sysdeps/x86_64/fpu/test-double-vlen8.c: Likewise.
        * sysdeps/x86_64/fpu/test-float-vlen16.c: Likewise.
        * sysdeps/x86_64/fpu/test-float-vlen4.c: Likewise.
        * sysdeps/x86_64/fpu/test-float-vlen4.h: Likewise.
        * sysdeps/x86_64/fpu/test-float-vlen8-avx2.c: Likewise.
        * sysdeps/x86_64/fpu/test-float-vlen8.c: Likewise.

-- 
Joseph S. Myers
address@hidden