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Diffstat (limited to 'usr/src/lib/libm/common/m9x/lrintf.c')
-rw-r--r--usr/src/lib/libm/common/m9x/lrintf.c72
1 files changed, 72 insertions, 0 deletions
diff --git a/usr/src/lib/libm/common/m9x/lrintf.c b/usr/src/lib/libm/common/m9x/lrintf.c
new file mode 100644
index 0000000000..06d5754853
--- /dev/null
+++ b/usr/src/lib/libm/common/m9x/lrintf.c
@@ -0,0 +1,72 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
+ */
+/*
+ * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#if defined(ELFOBJ)
+#pragma weak lrintf = __lrintf
+#endif
+
+#include <sys/isa_defs.h> /* _ILP32 */
+#include "libm.h"
+
+#if defined(_ILP32)
+long
+lrintf(float x) {
+ /*
+ * Note: The following code works on x86 (in the default rounding
+ * precision mode), but one should just use the fistpl instruction
+ * instead.
+ */
+ union {
+ unsigned i;
+ float f;
+ } xx, yy;
+ unsigned hx;
+
+ xx.f = x;
+ hx = xx.i & ~0x80000000;
+ if (hx < 0x4b000000) { /* |x| < 2^23 */
+ /* add and subtract a power of two to round x to an integer */
+#if defined(__sparc)
+ yy.i = (xx.i & 0x80000000) | 0x4b000000;
+#elif defined(__x86)
+ /* assume 64-bit precision */
+ yy.i = (xx.i & 0x80000000) | 0x5f000000;
+#else
+#error Unknown architecture
+#endif
+ x = (x + yy.f) - yy.f;
+ return ((long) x);
+ }
+
+ /* now x is nan, inf, or integral */
+ return ((long) x);
+}
+#else
+#error Unsupported architecture
+#endif /* defined(_ILP32) */