From 8c6c9236361fbc077769673c259828216403bc33 Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Wed, 30 Sep 2015 21:44:42 +0000 Subject: Fix i386 acosh (-qNaN) spurious "invalid" exception. The i386 versions of acoshf and acosh raise a spurious "invalid" exception for an argument that is a quiet NaN with the sign bit set. The integer arithmetic to detect arguments < 1 also detects -NaN, and then the computation 0 / 0 in that case raises the exception. This patch fixes this by using (x - x) / (x - x) as the computation in that case instead, which will always raise the exception for non-NaN arguments reaching that code, but not for quiet NaN arguments. Tested for x86_64 and x86. [BZ #19032] * sysdeps/i386/fpu/e_acosh.S (__ieee754_acosh): For arguments < 1, compute result as (x - x) / (x - x) not as 0 / 0. * sysdeps/i386/fpu/e_acoshf.S (__ieee754_acoshf): Likewise. * math/libm-test.inc (acosh_test_data): Add another test of acosh. --- ChangeLog | 6 ++++++ NEWS | 2 +- math/libm-test.inc | 1 + sysdeps/i386/fpu/e_acosh.S | 5 +++-- sysdeps/i386/fpu/e_acoshf.S | 5 +++-- 5 files changed, 14 insertions(+), 5 deletions(-) diff --git a/ChangeLog b/ChangeLog index ea038f7..958b4a3 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,11 @@ 2015-09-30 Joseph Myers + [BZ #19032] + * sysdeps/i386/fpu/e_acosh.S (__ieee754_acosh): For arguments < 1, + compute result as (x - x) / (x - x) not as 0 / 0. + * sysdeps/i386/fpu/e_acoshf.S (__ieee754_acoshf): Likewise. + * math/libm-test.inc (acosh_test_data): Add another test of acosh. + * math/auto-libm-test-in: Add more tests of acos, acosh, asin, atan, atan2, atanh, cbrt, cos, cosh, erf, erfc, exp, exp10, exp2 and expm1. diff --git a/NEWS b/NEWS index ea64dc7..e7e11bf 100644 --- a/NEWS +++ b/NEWS @@ -17,7 +17,7 @@ Version 2.23 18789, 18790, 18795, 18796, 18803, 18820, 18823, 18824, 18825, 18857, 18863, 18870, 18872, 18873, 18875, 18887, 18921, 18951, 18952, 18956, 18961, 18966, 18967, 18969, 18970, 18977, 18980, 18981, 18985, 19003, - 19016. + 19016, 19032. * The obsolete header has been removed. Programs that require this header must be updated to use instead. diff --git a/math/libm-test.inc b/math/libm-test.inc index 744c66d..8615957 100644 --- a/math/libm-test.inc +++ b/math/libm-test.inc @@ -1790,6 +1790,7 @@ static const struct test_f_f_data acosh_test_data[] = TEST_f_f (acosh, plus_infty, plus_infty, ERRNO_UNCHANGED), TEST_f_f (acosh, minus_infty, qnan_value, INVALID_EXCEPTION|ERRNO_EDOM), TEST_f_f (acosh, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_f_f (acosh, -qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), /* x < 1: */ TEST_f_f (acosh, 0.75L, qnan_value, INVALID_EXCEPTION|ERRNO_EDOM), diff --git a/sysdeps/i386/fpu/e_acosh.S b/sysdeps/i386/fpu/e_acosh.S index c5cd447..263c01a 100644 --- a/sysdeps/i386/fpu/e_acosh.S +++ b/sysdeps/i386/fpu/e_acosh.S @@ -91,9 +91,10 @@ ENTRY(__ieee754_acosh) fyl2x // log(2*x+1/(x+sqrt(x^2-1))) ret - // x < 1 => NaN + // x < 1 (or -NaN) => NaN .align ALIGNARG(4) -5: fldz +5: fldl 4(%esp) + fsub %st fdiv %st, %st(0) ret END(__ieee754_acosh) diff --git a/sysdeps/i386/fpu/e_acoshf.S b/sysdeps/i386/fpu/e_acoshf.S index 710267b..779a02c 100644 --- a/sysdeps/i386/fpu/e_acoshf.S +++ b/sysdeps/i386/fpu/e_acoshf.S @@ -91,9 +91,10 @@ ENTRY(__ieee754_acoshf) fyl2x // log(2*x+1/(x+sqrt(x^2-1))) ret - // x < 1 => NaN + // x < 1 (or -NaN) => NaN .align ALIGNARG(4) -5: fldz +5: flds 4(%esp) + fsub %st fdiv %st, %st(0) ret END(__ieee754_acoshf) -- cgit v1.1