The ldbl-128ibm implementation of fmodl has logic to detect when the
first argument has absolute value less than or equal to the second.
This logic is only correct for nonzero low parts; if the high parts
are equal and the low parts are zero, then the signs of the low parts
(which have no semantic effect on the value of the long double number)
can result in equal values being wrongly treated as unequal, and an
incorrect result being returned from fmodl. This patch fixes this by
checking for the case of zero low parts.
Although this does show up in tests from libm-test.inc (both tests of
fmodl, and, indirectly, of remainderl / dreml), the dependence on
non-semantic zero low parts means that test shouldn't be expected to
reproduce it reliably; thus, this patch adds a standalone test that
sets up affected values using unions.
Tested for powerpc.
[BZ #19602]
* sysdeps/ieee754/ldbl-128ibm/e_fmodl.c (__ieee754_fmodl): Handle
equal high parts and both low parts zero specially.
* sysdeps/ieee754/ldbl-128ibm/test-fmodl-ldbl-128ibm.c: New test.
* sysdeps/ieee754/ldbl-128ibm/Makefile [$(subdir) = math] (tests):
Add test-fmodl-ldbl-128ibm.
The ldbl-128ibm implementation of fmodl has completely bogus logic for
subnormal results (in this context, that means results for which the
result is in the subnormal range for double, not results with absolute
value below LDBL_MIN), based on code used for ldbl-128 that is correct
in that case but incorrect in the ldbl-128ibm use. This patch fixes
it to convert the mantissa into the correct form expected by
ldbl_insert_mantissa, removing the other cases of the code that were
incorrect and in one case unreachable for ldbl-128ibm. A correct
exponent value is then passed to ldbl_insert_mantissa to reflect the
shifted result.
Tested for powerpc.
[BZ #19595]
* sysdeps/ieee754/ldbl-128ibm/e_fmodl.c (__ieee754_fmodl): Use
common logic for all cases of shifting subnormal results. Do not
insert sign bit in shifted mantissa. Always pass -1023 as biased
exponent to ldbl_insert_mantissa in subnormal case.
http://sourceware.org/ml/libc-alpha/2013-08/msg00084.html
Another batch of ieee854 macros and union replacement. These four
files also have bugs fixed with this patch. The fact that the two
doubles in an IBM long double may have different signs means that
negation and absolute value operations can't just twiddle one sign bit
as you can with ieee864 style extended double. fmodl, remainderl,
erfl and erfcl all had errors of this type. erfl also returned +1 for
large magnitude negative input where it should return -1. The hypotl
error is innocuous since the value adjusted twice is only used as a
flag. The e_hypotl.c tests for large "a" and small "b" are mutually
exclusive because we've already exited when x/y > 2**120. That allows
some further small simplifications.
[BZ #15734], [BZ #15735]
* sysdeps/ieee754/ldbl-128ibm/e_fmodl.c (__ieee754_fmodl): Rewrite
all uses of ieee875 long double macros and unions. Simplify test
for 0.0L. Correct |x|<|y| and |x|=|y| test. Use
ldbl_extract_mantissa value for ix,iy exponents. Properly
normalize after ldbl_extract_mantissa, and don't add hidden bit
already handled. Don't treat low word of ieee854 mantissa like
low word of IBM long double and mask off bit when testing for
zero.
* sysdeps/ieee754/ldbl-128ibm/e_hypotl.c (__ieee754_hypotl): Rewrite
all uses of ieee875 long double macros and unions. Simplify tests
for 0.0L and inf. Correct double adjustment of k. Delete dead code
adjusting ha,hb. Simplify code setting kld. Delete two600 and
two1022, instead use their values. Recognise that tests for large
"a" and small "b" are mutually exclusive. Rename vars. Comment.
* sysdeps/ieee754/ldbl-128ibm/e_remainderl.c (__ieee754_remainderl):
Rewrite all uses of ieee875 long double macros and unions. Simplify
test for 0.0L and nan. Correct negation.
* sysdeps/ieee754/ldbl-128ibm/s_erfl.c (__erfl): Rewrite all uses of
ieee875 long double macros and unions. Correct output for large
magnitude x. Correct absolute value calculation.
(__erfcl): Likewise.
* math/libm-test.inc: Add tests for errors discovered in IBM long
double versions of fmodl, remainderl, erfl and erfcl.
Jakub Jelinek <jakub@redhat.com>
Roland McGrath <roland@redhat.com>
Steven Munroe <sjmunroe@us.ibm.com>
Alan Modra <amodra@bigpond.net.au>
* sysdeps/powerpc/powerpc64/fpu/s_truncf.S: Comment fix.
* sysdeps/powerpc/powerpc32/fpu/s_truncf.S: Likewise.
* sysdeps/powerpc/powerpc64/fpu/s_llroundf.S: Likewise.
* sysdeps/powerpc/fpu/libm-test-ulps: Update.
* math/libm-test.inc (check_float_internal): Allow ulp <= 0.5.
(erfc_test): Don't run erfcl (27.0L) test if erfcl (27.0L) is
denormal.
[TEST_LDOUBLE] (ceil_test, floor_test, llrint_test, llround_test,
rint_test, round_test, trunc_test): Add new tests.
* sysdeps/powerpc/powerpc32/fpu/s_copysignl.S: New file.
* sysdeps/powerpc/powerpc32/fpu/s_fabs.S: New file.
* sysdeps/powerpc/powerpc32/fpu/s_fabsl.S: New file.
* sysdeps/powerpc/powerpc32/fpu/s_fdim.c: New file.
* sysdeps/powerpc/powerpc32/fpu/s_fmax.S: New file.
* sysdeps/powerpc/powerpc32/fpu/s_fmin.S: New file.
* sysdeps/powerpc/powerpc32/fpu/s_isnan.c: New file.
* sysdeps/powerpc/powerpc64/fpu/s_ceill.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_copysignl.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_fabs.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_fabsl.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_fdim.c: New file.
* sysdeps/powerpc/powerpc64/fpu/s_floorl.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_fmax.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_fmin.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_isnan.c: New file.
* sysdeps/powerpc/powerpc64/fpu/s_llrintl.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_llroundl.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_lrintl.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_lroundl.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_nearbyintl.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_rintl.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_roundl.S: New file.
* sysdeps/powerpc/powerpc64/fpu/s_truncl.S: New file.
* sysdeps/unix/sysv/linux/powerpc/Implies: New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/fpu/Implies: New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/Implies: New file.
* sysdeps/unix/sysv/linux/powerpc/configure.in: New file.
* sysdeps/unix/sysv/linux/powerpc/configure: New file.
* sysdeps/unix/sysv/linux/powerpc/bits/wordsize.h
(__LONG_DOUBLE_MATH_OPTIONAL): Define.
(__NO_LONG_DOUBLE_MATH): Define.
* sysdeps/unix/sysv/linux/powerpc/nldbl-abi.h: New file.
* sysdeps/powerpc/fpu/s_isnan.c: Include math_ldbl_opt.h.
* sysdeps/powerpc/powerpc64/fpu/s_ceil.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (ceill): Add compatibility symbols.
* sysdeps/powerpc/powerpc64/fpu/s_copysign.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (copysignl): Add compatibility symbols.
* sysdeps/powerpc/powerpc64/fpu/s_floor.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (floorl): Add compatibility symbols.
* sysdeps/powerpc/powerpc64/fpu/s_llrint.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (llrintl, lrintl): Add compatibility symbols.
* sysdeps/powerpc/powerpc64/fpu/s_llround.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (llroundl, lroundl): Add compatibility symbols.
* sysdeps/powerpc/powerpc64/fpu/s_rint.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (rintl): Add compatibility symbols.
* sysdeps/powerpc/powerpc64/fpu/s_round.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (roundl): Add compatibility symbols.
* sysdeps/powerpc/powerpc64/fpu/s_trunc.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (truncl): Add compatibility symbols.
* sysdeps/powerpc/powerpc32/fpu/s_ceil.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (ceill): Add compatibility symbols.
* sysdeps/powerpc/powerpc32/fpu/s_copysign.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (copysignl): Add compatibility symbols.
* sysdeps/powerpc/powerpc32/fpu/s_floor.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (floorl): Add compatibility symbols.
* sysdeps/powerpc/powerpc32/fpu/s_lrint.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (lrintl): Add compatibility symbols.
* sysdeps/powerpc/powerpc32/fpu/s_llrint.c: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (llrintl): Add compatibility symbols.
* sysdeps/powerpc/powerpc32/fpu/s_lround.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (lroundl): Add compatibility symbols.
* sysdeps/powerpc/powerpc32/fpu/s_rint.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (rintl): Add compatibility symbols.
* sysdeps/powerpc/powerpc32/fpu/s_round.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (roundl): Add compatibility symbols.
* sysdeps/powerpc/powerpc32/fpu/s_trunc.S: Include math_ldbl_opt.h.
[LONG_DOUBLE_COMPAT] (truncl): Add compatibility symbols.
* misc/qefgcvt_r.c [LDBL_MIN_10_EXP == -291] (FLOAT_MIN_10_NORM): New.
* sysdeps/powerpc/fpu/bits/mathdef.h (__NO_LONG_DOUBLE_MATH): Remove.
* sysdeps/powerpc/Implies: Add ieee754/ldbl-128ibm.
* sysdeps/powerpc/powerpc32/Implies: Remove powerpc/soft-fp.
* sysdeps/ieee754/ldbl-128ibm/Makefile: New file.
* sysdeps/ieee754/ldbl-128ibm/e_acoshl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_acosl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_asinl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_atan2l.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_atanhl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_coshl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_expl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_fmodl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_hypotl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_j0l.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_j1l.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_jnl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_lgammal_r.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_log10l.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_log2l.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_logl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_powl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_rem_pio2l.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_remainderl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_sinhl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/e_sqrtl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/ieee754.h: New file.
* sysdeps/ieee754/ldbl-128ibm/k_cosl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/k_sincosl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/k_sinl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/k_tanl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c: New file.
* sysdeps/ieee754/ldbl-128ibm/math_ldbl.h: New file.
* sysdeps/ieee754/ldbl-128ibm/mpn2ldbl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/printf_fphex.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_asinhl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_atanl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_cbrtl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_cosl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_erfl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_expm1l.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_fabsl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_finitel.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_fpclassifyl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_frexpl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_ilogbl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_isinfl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_isnanl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_log1pl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_logbl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_modfl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_remquol.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_rintl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_scalblnl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_scalbnl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_signbitl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_sincosl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_sinl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_tanhl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_tanl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_truncl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/strtold_l.c: New file.
* sysdeps/ieee754/ldbl-128ibm/t_sincosl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/w_expl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_copysignl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_floorl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_llrintl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_llroundl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_roundl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_ceill.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_lrintl.c: New file.
* sysdeps/ieee754/ldbl-128ibm/s_lroundl.c: New file.
* sysdeps/ieee754/ldbl-128/e_powl.c: Fix old comment.
