From 18daae313531ed597d0f6227d15af00b04b104c8 Mon Sep 17 00:00:00 2001 From: Szabolcs Nagy Date: Thu, 18 Sep 2014 17:02:24 +0200 Subject: [PATCH] math: fix exp10 not to raise invalid exception on NaN This was not caught earlier because gcc incorrectly generates quiet relational operators that never raise exceptions. --- src/math/exp10.c | 5 ++++- src/math/exp10f.c | 5 ++++- src/math/exp10l.c | 7 +++++-- 3 files changed, 13 insertions(+), 4 deletions(-) diff --git a/src/math/exp10.c b/src/math/exp10.c index 16d704a7..9f5e3c2c 100644 --- a/src/math/exp10.c +++ b/src/math/exp10.c @@ -1,5 +1,6 @@ #define _GNU_SOURCE #include +#include #include "libc.h" double exp10(double x) @@ -11,7 +12,9 @@ double exp10(double x) 1e10, 1e11, 1e12, 1e13, 1e14, 1e15 }; double n, y = modf(x, &n); - if (fabs(n) < 16) { + union {double f; uint64_t i;} u = {n}; + /* fabs(n) < 16 without raising invalid on nan */ + if ((u.i>>52 & 0x7ff) < 0x3ff+4) { if (!y) return p10[(int)n+15]; y = exp2(3.32192809488736234787031942948939 * y); return y * p10[(int)n+15]; diff --git a/src/math/exp10f.c b/src/math/exp10f.c index 5fd1af9c..7a8d4470 100644 --- a/src/math/exp10f.c +++ b/src/math/exp10f.c @@ -1,5 +1,6 @@ #define _GNU_SOURCE #include +#include #include "libc.h" float exp10f(float x) @@ -9,7 +10,9 @@ float exp10f(float x) 1, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7 }; float n, y = modff(x, &n); - if (fabsf(n) < 8) { + union {float f; uint32_t i;} u = {n}; + /* fabsf(n) < 8 without raising invalid on nan */ + if ((u.i>>23 & 0xff) < 0x7f+3) { if (!y) return p10[(int)n+7]; y = exp2f(3.32192809488736234787031942948939f * y); return y * p10[(int)n+7]; diff --git a/src/math/exp10l.c b/src/math/exp10l.c index 4f9469ae..b758ebff 100644 --- a/src/math/exp10l.c +++ b/src/math/exp10l.c @@ -2,13 +2,14 @@ #include #include #include "libc.h" +#include "libm.h" #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024 long double exp10l(long double x) { return exp10(x); } -#else +#elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384 long double exp10l(long double x) { static const long double p10[] = { @@ -18,7 +19,9 @@ long double exp10l(long double x) 1e10, 1e11, 1e12, 1e13, 1e14, 1e15 }; long double n, y = modfl(x, &n); - if (fabsl(n) < 16) { + union ldshape u = {n}; + /* fabsl(n) < 16 without raising invalid on nan */ + if ((u.i.se & 0x7fff) < 0x3fff+4) { if (!y) return p10[(int)n+15]; y = exp2l(3.32192809488736234787031942948939L * y); return y * p10[(int)n+15]; -- 2.25.1