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authordarylm503 <darylm503@6f19259b-4bc3-4df7-8a09-765794883524>2011-04-27 21:42:16 +0000
committerdarylm503 <darylm503@6f19259b-4bc3-4df7-8a09-765794883524>2011-04-27 21:42:16 +0000
commit2aa62f2bc9a9654687b377d9ca8a8c2c860a3852 (patch)
tree62a0991a44327154fb88bf95bd6f7522053db7bb /StdLib/LibC/Main/Arm
parent98790d814871cc30bbd536673d3a0948047cd2f0 (diff)
downloadedk2-platforms-2aa62f2bc9a9654687b377d9ca8a8c2c860a3852.tar.xz
Standard Libraries for EDK II.
This set of three packages: AppPkg, StdLib, StdLibPrivateInternalFiles; contains the implementation of libraries based upon non-UEFI standards such as ISO/IEC-9899, the library portion of the C Language Standard, POSIX, etc. AppPkg contains applications that make use of the standard libraries defined in the StdLib Package. StdLib contains header (include) files and the implementations of the standard libraries. StdLibPrivateInternalFiles contains files for the exclusive use of the library implementations in StdLib. These files should never be directly referenced from applications or other code. git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@11600 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'StdLib/LibC/Main/Arm')
-rw-r--r--StdLib/LibC/Main/Arm/flt_rounds.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/StdLib/LibC/Main/Arm/flt_rounds.c b/StdLib/LibC/Main/Arm/flt_rounds.c
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+++ b/StdLib/LibC/Main/Arm/flt_rounds.c
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+/* $NetBSD: flt_rounds.c,v 1.3 2006/02/25 00:58:35 wiz Exp $ */
+
+/*
+ * Copyright (c) 1996 Mark Brinicombe
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by Mark Brinicombe
+ * for the NetBSD Project.
+ * 4. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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>
+#if defined(LIBC_SCCS) && !defined(lint)
+__RCSID("$NetBSD: flt_rounds.c,v 1.3 2006/02/25 00:58:35 wiz Exp $");
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/types.h>
+#include <ieeefp.h>
+
+static const int map[] = {
+ 1, /* round to nearest */
+ 2, /* round to positive infinity */
+ 3, /* round to negative infinity */
+ 0 /* round to zero */
+};
+
+/*
+ * Return the current FP rounding mode
+ *
+ * Returns:
+ * 0 - round to zero
+ * 1 - round to nearest
+ * 2 - round to postive infinity
+ * 3 - round to negative infinity
+ *
+ * ok all we need to do is get the current FP rounding mode
+ * index our map table and return the appropriate value.
+ *
+ * HOWEVER:
+ * The ARM FPA codes the rounding mode into the actual FP instructions
+ * so there is no such thing as a global rounding mode.
+ * The default is round to nearest if rounding is not explicitly specified.
+ * FP instructions generated by GCC will not explicitly specify a rounding
+ * mode.
+ *
+ * So the best we can do it to return the rounding mode FP instructions
+ * use if rounding is not specified which is round to nearest.
+ *
+ * This could change in the future with new floating point emulators or
+ * soft float FP libraries.
+ */
+
+int __flt_rounds(void);
+
+int
+__flt_rounds()
+{
+ return(map[fpgetround()]);
+}