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* Fix implicit __isinf declarations in exp.Joseph Myers2014-03-241-0/+1
| | | | | | | | | | | | | | | My recent exp patch introduced warnings about implicit __isinf declarations in exp because e_exp.c didn't include <math.h>. This patch fixes this. Because <math.h> can't be included after <math_private.h> (because of macro definitions of __nan*), it was necessary to put an include in sysdeps/x86_64/fpu/multiarch/e_exp.c as well. Tested x86_64. * sysdeps/ieee754/dbl-64/e_exp.c: Include <math.h>. * sysdeps/x86_64/fpu/multiarch/e_exp.c [HAVE_FMA4_SUPPORT || HAVE_AVX_SUPPORT]: Likewise.
* Fix dbl-64 exp overflow/underflow in non-default rounding modes (bug 16284).Joseph Myers2014-03-241-143/+153
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The dbl-64 version of exp needs round-to-nearest mode for its internal computations, but that has the consequence of inappropriate overflowing and underflowing results in other rounding modes. This patch fixes this by recomputing the relevant results in cases where the round-to-nearest result overflows to infinity or underflows to zero (most of the diffs are actually just consequent reindentation). Tests are enabled in all rounding modes for complex functions using exp - but not for cexp because it turns out there are bugs causing spurious underflows for cexp for some tests, which will need to be fixed separately (I suspect ccos ccosh csin csinh ctan ctanh have similar bugs, just not shown by the present set of test inputs). Tested x86_64 and x86 and ulps updated accordingly. [BZ #16284] * sysdeps/ieee754/dbl-64/e_exp.c (__ieee754_exp): Use original rounding mode to recompute results that overflow to infinity or underflow to zero. * math/auto-libm-test-in: Don't mark tests as expected to fail for bug 16284. * math/auto-libm-test-out: Regenerated. * math/libm-test.inc (ccos_test): Use ALL_RM_TEST. (ccosh_test): Likewise. (csin_test_data): Use plus_oflow. (csin_test): Use ALL_RM_TEST. (csinh_test_data): Use plus_oflow. (csinh_test): Use ALL_RM_TEST. * sysdeps/i386/fpu/libm-test-ulps: Update. * sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
* Fix log (1) in round-downward mode (bug 16731).Joseph Myers2014-03-212-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | According to ISO C Annex F, log (1) should be +0 in all rounding modes, but some implementations in glibc wrongly return -0 in round-downward mode (mapping to log1p (x - 1) is problematic because 1 - 1 is -0 in round-downward mode, and log1p (-0) is -0). This patch fixes this. (It helps with some implementations of other functions such as acosh, log2 and log10 that call out to log, but not enough to enable all-rounding-modes testing for those functions without further fixes to other implementations of them.) Tested x86_64 and x86 and ulps updated accordingly, and did spot tests for mips64 for the ldbl-128 fix, and i586 for the sysdeps/i386/fpu implementations shadowed by those in sysdeps/i386/i686/fpu. [BZ #16731] * sysdeps/i386/fpu/e_log.S (__ieee754_log): Take absolute value when x - 1 is zero. * sysdeps/i386/fpu/e_logf.S (__ieee754_logf): Likewise. * sysdeps/i386/fpu/e_logl.S (__ieee754_logl): Likewise. * sysdeps/i386/i686/fpu/e_logl.S (__ieee754_logl): Likewise. * sysdeps/ieee754/dbl-64/e_log.c (__ieee754_log): Return +0 when argument is 1. * sysdeps/ieee754/ldbl-128/e_logl.c (__ieee754_logl): Likewise. * sysdeps/x86_64/fpu/e_logl.S: Take absolute value when x - 1 is zero. * math/libm-test.inc (log_test): Use ALL_RM_TEST. * sysdeps/i386/fpu/libm-test-ulps: Update. * sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
* Fix nextafter overflow in non-default rounding modes (bug 16677).Joseph Myers2014-03-113-9/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ISO C requires the result of nextafter to be independent of the rounding mode, even when underflow or overflow occurs. This patch fixes the bug in various nextafter implementations that, having done an overflowing computation to force an overflow exception (correct), they then return the result of that computation rather than an infinity computed some other way (incorrect, when the overflowing result of arithmetic with that sign and rounding mode is finite but the correct result is infinite) - generally by falling through to existing code to return a value that in fact is correct for this case (but was computed by an integer increment and so without generating the exceptions required). Having fixed the bug, the previously deferred conversion of nextafter testing in libm-test.inc to ALL_RM_TEST is also included. Tested x86_64 and x86; also spot-checked results of nextafter tests for powerpc32 and mips64 to test the ldbl-128ibm and ldbl-128 changes. (The m68k change is untested.) [BZ #16677] * math/s_nextafter.c (__nextafter): Do not return value from overflowing computation. * sysdeps/i386/fpu/s_nextafterl.c (__nextafterl): Likewise. * sysdeps/ieee754/flt-32/s_nextafterf.c (__nextafterf): Likewise. * sysdeps/ieee754/ldbl-128/s_nextafterl.c (__nextafterl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c (__nextafterl): Likewise. * sysdeps/m68k/m680x0/fpu/s_nextafterl.c (__nextafterl): Likewise. * math/libm-test.inc (nextafter_test): Use ALL_RM_TEST.
* Fix sign of input to bsloww1 (BZ #16623)Siddhesh Poyarekar2014-02-271-6/+10
| | | | | | | | In 84ba214c, I removed some redundant sign computations and in the process, I incorrectly got rid of a temporary variable, thus passing the absolute value of the input to bsloww1. This caused #16623. This fix undoes the incorrect change.
* BZ #16447: Fix ldbl-128 expl implementation.Andreas Krebbel2014-02-111-1/+1
| | | | | Extend the range of numbers handled via unsafe mode. Add expl testcase and regenerate ULPs for s390.
* Use glibc_likely instead __builtin_expect.Ondřej Bílka2014-02-1042-129/+129
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* [BZ #16427] Fix ldbl-128 exp overflows.Andreas Krebbel2014-01-151-13/+5
| | | | | Invoke the non-IEEE handling only for numbers special also in the IEEE case. This aligns the exp handling with the other ldbl variants.
* PowerPC: remove wrong truncl implementation for PowerPC64Adhemerval Zanella2014-01-081-3/+0
| | | | | | | | | | | | | | | The truncl assembly implementation (sysdeps/powerpc/powerpc64/fpu/s_truncl.S) returns wrong results for some inputs where first double is a exact integer and the precision is determined by second long double. Checking on implementation comments and history, I am very confident the assembly implementation was based on a version before commit 5c68d401698a58cf7da150d9cce769fa6679ba5f that fixes BZ#2423 (Errors in long double (ldbl-128ibm) rounding functions in glibc-2.4). By just removing the implementation and make the build select sysdeps/ieee754/ldbl-128ibm/s_truncl.c instead it fixes tgammal issues regarding wrong result sign.
* Fix ldbl-128ibm expm1l on large arguments (bug 16408).Joseph Myers2014-01-081-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes bug 16408, ldbl-128ibm expm1l returning NaN for some large arguments. The basic problem is that the approach of converting the exponent to the form n * log(2) + y, where -0.5 <= y <= 0.5, then computing 2^n * expm1(y) + (2^n - 1) falls over when 2^n overflows (starting slightly before the point where expm1 overflows, when y is negative and n is the least integer for which 2^n overflows). The ldbl-128 code, and the x86/x86_64 code, make expm1l fall back to expl for large positive arguments to avoid this issue. This patch makes the ldbl-128ibm code do the same. (The problem appears for the particular argument in the testsuite because the ldbl-128ibm code also uses an overflow threshold that's for ldbl-128 and is too big for ldbl-128ibm, but the problem described applies for large non-overflowing cases as well, although during the freeze is not a suitable time for making the expm1 tests cover cases close to overflow more thoroughly.) This leaves some code for large positive arguments in expm1l that is now dead. To keep the code for ldbl-128 and ldbl-128ibm similar, and to avoid unnecessary changes during the freeze, the patch doesn't remove it; instead I propose to file a bug in Bugzilla as a reminder that this code (for overflow, including errno setting, and for arguments of +Inf) is no longer needed and should be removed from both those expm1l implementations. Tested powerpc32. * sysdeps/ieee754/ldbl-128ibm/s_expm1l.c (__expm1l): Use __expl for large positive arguments.
* Fix ldbl-128ibm coshl spurious overflows (bug 16407).Joseph Myers2014-01-071-1/+1
| | | | | | | | | | | | | | | | | | | | | This patch fixes bug 16407, spurious overflows from ldbl-128ibm coshl. The implementation assumed that a high part (reinterpreted as an integer) of the absolute value of the argument of 0x408633ce8fb9f87dLL or more meant overflow, but the actual threshold has high part 0x408633ce8fb9f87eLL (and a negative low part). The patch adjusts the threshold accordingly. sinhl probably has the same issue, but I didn't get that far in adding tests of special cases (such as just below and above overflow) before the freeze and during the freeze is not a suitable time to add them (as they'd require ulps to be regenerated again), so I'm not changing that function for now; when I add more tests of special cases, we'll discover whether sinhl indeed has this problem. Tested powerpc32. * sysdeps/ieee754/ldbl-128ibm/e_coshl.c (__ieee754_coshl): Increase overflow threshold.
* Fix ldbl-128 / ldbl-128ibm lgammal spurious underflow (bug 16400).Joseph Myers2014-01-061-1/+3
| | | | | | | | | | | | | | This patch fixes bug 16400, spurious underflow exceptions for ldbl-128 / ldbl-128ibm lgammal with small positive arguments, by just using -__logl (x) as the result in the problem cases (similar to the previous fix for problems with small negative arguments). Tested powerpc32, and also tested on mips64 that this does not require ulps regeneration for the ldbl-128 case. * sysdeps/ieee754/ldbl-128/e_lgammal_r.c (__ieee754_lgammal_r): Return -__logl (x) for small positive arguments without evaluating a polynomial.
* Fix ldbl-128ibm logl inaccuracy (bug 16386).Joseph Myers2014-01-021-0/+8
| | | | | | | | | | | | This patch fixes bug 16386, ldbl-128ibm logl inaccuracy (with consequent inaccuracy for lgammal) for arguments where the high double is subnormal, which showed up while attempting to regenerate ulps for powerpc-nofpu for 2.19. The problem here is logic failing to allow for subnormals when calculating the exponent of the argument. Tested for powerpc-nofpu. * sysdeps/ieee754/ldbl-128ibm/e_logl.c (__ieee754_logl): Adjust numbers with subnormal high part when calculating exponent.
* Fix ldbl-128ibm asinhl inaccuracy (bug 16385).Joseph Myers2014-01-021-1/+1
| | | | | | | | | | | This patch fixes bug 16385, ldbl-128ibm asinhl inaccuracy, which showed up while attempting to regenerate ulps for powerpc-nofpu for 2.19. The problem here was use of fabs instead of fabsl meaning large arguments were reduced to the precision of double. Tested for powerpc-nofpu. * sysdeps/ieee754/ldbl-128ibm/s_asinhl.c (__asinhl): Use fabsl not fabs.
* Fix ldbl-128ibm acoshl inaccuracy (bug 16384).Joseph Myers2014-01-021-2/+2
| | | | | | | | | | | | | | | This patch fixes bug 16384, ldbl-128ibm acoshl inaccuracy, which showed up while attempting to regenerate ulps for powerpc-nofpu for 2.19. There were two separate problems, use of __log1p instead of __log1pl and an insufficiently accurate constant value for log 2 (which this patch replaces by use of M_LN2l), each of which could cause substantial inaccuracy in affected cases. Tested for powerpc-nofpu. * sysdeps/ieee754/ldbl-128ibm/e_acoshl.c (ln2): Initialize with M_LN2l. (__ieee754_acoshl): Use __log1pl not __log1p.
* Update copyright notices with scripts/update-copyrightsAllan McRae2014-01-01205-205/+205
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* Fix typo in csloww()Allan McRae2013-12-271-1/+1
| | | | | An incorrect variable name was used during the refactoring done in commit 4aafb73c.
* Fix ldbl-128 lgammal for small negative arguments (bug 16337).Joseph Myers2013-12-221-2/+2
| | | | | | | | | | | | | | | | | | | | | This patch fixes bug 16337, ldbl-128 lgammal spurious overflows for small negative arguments (the arguments in question are already in the testsuite). The implementation uses the reflection formula to compute lgamma of negative x from lgamma of -x, effectively resulting in a calculation -log(x^2) + log(-x); cancellation isn't problematic in this case (bugs for problematic cancellation in lgamma are 2542, 2543, 2558), but the x^2 calculation can underflow (in which case there is spurious logic to return an overflowing value - lgamma can only ever correctly overflow for large positive arguments, though tgamma can overflow for small arguments of either sign as well as large positive arguments). The fix is simply to calculate the result directly with logl when the argument is a small enough negative number. Tested mips64. * sysdeps/ieee754/ldbl-128/e_lgammal_r.c (__ieee754_lgammal_r): Calculate results for small negative arguments directly rather than using reflection formula with special underflow handling.
* Consolidate code to compute sin and cos from lookup tablesSiddhesh Poyarekar2013-12-201-232/+129
| | | | | | | | | | | This patch consolidates the multiple copies of code that looks up sin and cos of a number from the lookup table and computes the final value, into static functions. This does not have a noticeable performance impact since the functions are inlined by gcc. There is further scope for consolidation in the functions but they cause a more noticable impact on performance (>5%) due to which I have held back on them.
* Remove more redundant computations in s_sin.cSiddhesh Poyarekar2013-12-201-42/+33
| | | | | | | | Removed more redundant computations in the slow paths of the sin and cos functions. The notable change is the passing of the most significant bits of X to the slow functions to check if X is positive so that just the absolute value of x can be passed and the repeated ABS() operation is avoided.
* Remove redundant arguments in reduce_and_computeSiddhesh Poyarekar2013-12-201-4/+4
| | | | | The A and DA arguments in reduce_and_compute are useless and hence have been removed.
* Remove some redundant computations in s_sin.cSiddhesh Poyarekar2013-12-201-24/+15
| | | | | | | | There are multiple points in the code where the absolute value of a number is computed multiple times or is computed even though the value can only be positive. This change removes those redundant computations. Tested on x86_64 to verify that there were no regressions in the testsuite.
* Compile e_sqrt.c with -ffp-contract=off.Marcus Shawcroft2013-12-181-0/+1
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* Fix ldbl-128 logl for subnormals (bug 16338).Joseph Myers2013-12-181-3/+2
| | | | | | | | | | | | | | | | | | | | | | This patch fixes bug 16338, ldbl-128 logl not handling subnormals (with consequent inaccuracy for lgammal as well). The fix is simply to use __frexpl when determining the exponent, as done already in log2l and log10l. Given the lack of testing of small arguments to any of the log* functions, appropriate tests are added for all of them. Tested x86_64 and x86 and ulps updated accordingly, and spot tests also run for mips64 to confirm the ldbl-128 fix. Note that while this fixes lgammal inaccuracy for small positive arguments, I suspect that there will still be problems with spurious underflows in that case. * sysdeps/ieee754/ldbl-128/e_logl.c (__ieee754_logl): Use __frexpl to determine exponent and adjust argument to have exponent of -1. * math/auto-libm-test-in: Add more tests of log, log10, log1p and log2. * math/auto-libm-test-out: Regenerated. * sysdeps/x86_64/fpu/libm-test-ulps: Update.
* Fix dbl-64 hypot spurious underflows (bug 16314).Joseph Myers2013-12-171-1/+1
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* Fix hypot handling of subnormals (bug 16316, bug 16330).Joseph Myers2013-12-173-0/+33
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* Minor code cleanup in s_sin.cSiddhesh Poyarekar2013-12-161-20/+13
| | | | | | | - Remove redundant mynumber union definitions - Clean up a clumsy ternary operator - Rename TAYLOR_SINCOS to TAYLOR_SIN since we're only expanding the sin Taylor series in it.
* Consolidate definition of constant t22Siddhesh Poyarekar2013-12-111-9/+3
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* Use double constants instead of the struct numberSiddhesh Poyarekar2013-12-112-136/+106
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* PowerPC: multiarch logb/logbf/logbl for PowerPC32Adhemerval Zanella2013-12-061-1/+2
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* PowerPC: multiarch finite/finitef for PowerPC32Adhemerval Zanella2013-12-062-3/+12
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* Fix Bessel function error handling (bug 6807, bug 15901).Joseph Myers2013-12-044-10/+13
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* Fix exp missing underflows (bug 15268, bug 15425).Joseph Myers2013-12-031-3/+14
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* Fix erfc errno setting on underflow (bug 6786).Joseph Myers2013-12-035-10/+65
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* Remove unused ldbl-96 functions (bug 15004).Joseph Myers2013-11-2816-1046/+0
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* Fix dbl-64 e_sqrt.c for non-default rounding modes (bug 16271).Joseph Myers2013-11-281-4/+34
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* PowerPC: Set/restore rounding mode only when neededAdhemerval Zanella2013-11-254-21/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | This patch helps some math functions performance by adding the libc_fexxx variant of inline functions to handle both FPU round and exception set/restore and by using them on the libc_fexxx_ctx functions. It is based on already coded fexxx family functions for PPC with fpu. Here is the summary of performance improvements due this patch (measured on a POWER7 machine): Before: cos(): ITERS:9.5895e+07: TOTAL:5116.03Mcy, MAX:77.6cy, MIN:49.792cy, 18744 calls/Mcy exp(): ITERS:2.827e+07: TOTAL:5187.15Mcy, MAX:494.018cy, MIN:38.422cy, 5450.01 calls/Mcy pow(): ITERS:6.1705e+07: TOTAL:5144.26Mcy, MAX:171.95cy, MIN:29.935cy, 11994.9 calls/Mcy sin(): ITERS:8.6898e+07: TOTAL:5117.06Mcy, MAX:83.841cy, MIN:46.582cy, 16982 calls/Mcy tan(): ITERS:2.9473e+07: TOTAL:5115.39Mcy, MAX:191.017cy, MIN:172.352cy, 5761.63 calls/Mcy After: cos(): ITERS:2.05265e+08: TOTAL:5111.37Mcy, MAX:78.754cy, MIN:24.196cy, 40158.5 calls/Mcy exp(): ITERS:3.341e+07: TOTAL:5170.84Mcy, MAX:476.317cy, MIN:15.574cy, 6461.23 calls/Mcy pow(): ITERS:7.6153e+07: TOTAL:5129.1Mcy, MAX:147.5cy, MIN:30.916cy, 14847.2 calls/Mcy sin(): ITERS:1.58816e+08: TOTAL:5115.11Mcy, MAX:1490.39cy, MIN:22.341cy, 31048.4 calls/Mcy tan(): ITERS:3.4964e+07: TOTAL:5114.18Mcy, MAX:177.422cy, MIN:146.115cy, 6836.68 calls/Mcy
* Add systemtap probe markers for sin, cos, asin and acosSiddhesh Poyarekar2013-11-201-0/+5
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* rename configure.in to configure.acMike Frysinger2013-10-302-1/+1
| | | | | | | Autoconf has been deprecating configure.in for quite a long time. Rename all our configure.in and preconfigure.in files to .ac. Signed-off-by: Mike Frysinger <vapier@gentoo.org>
* Consolidate conditionals in mp sin/cos functionsSiddhesh Poyarekar2013-10-281-8/+6
| | | | | Consolidate conditionals in multiple precision sin and cos functions to prepare the code for addition of probe points.
* Format floating routines.Ondřej Bílka2013-10-1758-2175/+2769
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* Add systemtap markers to math function slow pathsSiddhesh Poyarekar2013-10-116-5/+45
| | | | | | | Add systemtap probes to various slow paths in libm so that application developers may use systemtap to find out if their applications are hitting these slow paths. We have added probes for pow, exp, log, tan, atan and atan2.
* Avoid ordered comparisons of NaNs in ldbl-128ibm acosl and asinl.Joseph Myers2013-10-102-0/+4
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* Format e_pow.cSiddhesh Poyarekar2013-10-081-260/+313
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* Format e_exp.cSiddhesh Poyarekar2013-10-081-164/+242
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* Consolidate multiple precision sin/cos functionsSiddhesh Poyarekar2013-10-082-125/+111
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* PowerPC floating point little-endian [6 of 15]Alan Modra2013-10-041-28/+23
| | | | | | | | | | | http://sourceware.org/ml/libc-alpha/2013-07/msg00197.html A rewrite to make this code correct for little-endian. * sysdeps/ieee754/ldbl-128ibm/e_sqrtl.c (mynumber): Replace union 32-bit int array member with 64-bit int array. (t515, tm256): Double rather than long double. (__ieee754_sqrtl): Rewrite using 64-bit arithmetic.
* PowerPC floating point little-endian [5 of 15]Alan Modra2013-10-042-56/+0
| | | | | | | | | | | | http://sourceware.org/ml/libc-alpha/2013-08/msg00085.html Rid ourselves of ieee854. * sysdeps/ieee754/ldbl-128ibm/ieee754.h (union ieee854_long_double): Delete. (IEEE854_LONG_DOUBLE_BIAS): Delete. * sysdeps/ieee754/ldbl-128ibm/math_ldbl.h: Don't include ieee854 version of math_ldbl.h.
* PowerPC floating point little-endian [4 of 15]Alan Modra2013-10-044-134/+152
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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.
* PowerPC floating point little-endian [3 of 15]Alan Modra2013-10-0421-240/+284
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | http://sourceware.org/ml/libc-alpha/2013-08/msg00083.html Further replacement of ieee854 macros and unions. These files also have some optimisations for comparison against 0.0L, infinity and nan. Since the ABI specifies that the high double of an IBM long double pair is the value rounded to double, a high double of 0.0 means the low double must also be 0.0. The ABI also says that infinity and nan are encoded in the high double, with the low double unspecified. This means that tests for 0.0L, +/-Infinity and +/-NaN need only check the high double. * sysdeps/ieee754/ldbl-128ibm/e_atan2l.c (__ieee754_atan2l): Rewrite all uses of ieee854 long double macros and unions. Simplify tests for long doubles that are fully specified by the high double. * sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c (__ieee754_gammal_r): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_ilogbl.c (__ieee754_ilogbl): Likewise. Remove dead code too. * sysdeps/ieee754/ldbl-128ibm/e_jnl.c (__ieee754_jnl): Likewise. (__ieee754_ynl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_log10l.c (__ieee754_log10l): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_logl.c (__ieee754_logl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Likewise. Remove dead code too. * sysdeps/ieee754/ldbl-128ibm/k_tanl.c (__kernel_tanl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_expm1l.c (__expm1l): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_frexpl.c (__frexpl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_isinf_nsl.c (__isinf_nsl): Likewise. Simplify. * sysdeps/ieee754/ldbl-128ibm/s_isinfl.c (___isinfl): Likewise. Simplify. * sysdeps/ieee754/ldbl-128ibm/s_log1pl.c (__log1pl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_modfl.c (__modfl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c (__nextafterl): Likewise. Comment on variable precision. * sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c (__nexttoward): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_remquol.c (__remquol): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_scalblnl.c (__scalblnl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_scalbnl.c (__scalbnl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_tanhl.c (__tanhl): Likewise. * sysdeps/powerpc/fpu/libm-test-ulps: Adjust tan_towardzero ulps.