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-rw-r--r--libm/src/s_lrint.c58
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diff --git a/libm/src/s_lrint.c b/libm/src/s_lrint.c
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+/*-
+ * Copyright (c) 2005 David Schultz <das@FreeBSD.ORG>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+#include <fenv.h>
+#include <math.h>
+
+#ifndef type
+/* __FBSDID("$FreeBSD: src/lib/msun/src/s_lrint.c,v 1.1 2005/01/11 23:12:55 das Exp $"); */
+#define type double
+#define roundit rint
+#define dtype long
+#define fn lrint
+#endif
+
+/*
+ * C99 says we should not raise a spurious inexact exception when an
+ * invalid exception is raised. Unfortunately, the set of inputs
+ * that overflows depends on the rounding mode when 'dtype' has more
+ * significant bits than 'type'. Hence, we bend over backwards for the
+ * sake of correctness; an MD implementation could be more efficient.
+ */
+dtype
+fn(type x)
+{
+ fenv_t env;
+ dtype d;
+
+ feholdexcept(&env);
+ d = (dtype)roundit(x);
+ if (fetestexcept(FE_INVALID))
+ feclearexcept(FE_INEXACT);
+ feupdateenv(&env);
+ return (d);
+}