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| author | darylm503 <darylm503@6f19259b-4bc3-4df7-8a09-765794883524> | 2011-04-27 21:42:16 +0000 |
|---|---|---|
| committer | darylm503 <darylm503@6f19259b-4bc3-4df7-8a09-765794883524> | 2011-04-27 21:42:16 +0000 |
| commit | 2aa62f2bc9a9654687b377d9ca8a8c2c860a3852 (patch) | |
| tree | 62a0991a44327154fb88bf95bd6f7522053db7bb /StdLib/LibC/Math/s_modf.c | |
| parent | 98790d814871cc30bbd536673d3a0948047cd2f0 (diff) | |
| download | edk2-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/Math/s_modf.c')
| -rw-r--r-- | StdLib/LibC/Math/s_modf.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/StdLib/LibC/Math/s_modf.c b/StdLib/LibC/Math/s_modf.c new file mode 100644 index 0000000000..bf4faf42e0 --- /dev/null +++ b/StdLib/LibC/Math/s_modf.c @@ -0,0 +1,76 @@ +/* @(#)s_modf.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+#include <LibConfig.h>
+#include <sys/EfiCdefs.h>
+#if defined(LIBM_SCCS) && !defined(lint)
+__RCSID("$NetBSD: s_modf.c,v 1.11 2002/05/26 22:01:57 wiz Exp $");
+#endif
+
+/*
+ * modf(double x, double *iptr)
+ * return fraction part of x, and return x's integral part in *iptr.
+ * Method:
+ * Bit twiddling.
+ *
+ * Exception:
+ * No exception.
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+static const double one = 1.0;
+
+double
+modf(double x, double *iptr)
+{
+ int32_t i0,i1,j0;
+ u_int32_t i;
+ EXTRACT_WORDS(i0,i1,x);
+ j0 = ((i0>>20)&0x7ff)-0x3ff; /* exponent of x */
+ if(j0<20) { /* integer part in high x */
+ if(j0<0) { /* |x|<1 */
+ INSERT_WORDS(*iptr,i0&0x80000000,0); /* *iptr = +-0 */
+ return x;
+ } else {
+ i = (0x000fffff)>>j0;
+ if(((i0&i)|i1)==0) { /* x is integral */
+ u_int32_t high;
+ *iptr = x;
+ GET_HIGH_WORD(high,x);
+ INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */
+ return x;
+ } else {
+ INSERT_WORDS(*iptr,i0&(~i),0);
+ return x - *iptr;
+ }
+ }
+ } else if (j0>51) { /* no fraction part */
+ u_int32_t high;
+ *iptr = x*one;
+ GET_HIGH_WORD(high,x);
+ INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */
+ return x;
+ } else { /* fraction part in low x */
+ i = ((u_int32_t)(0xffffffff))>>(j0-20);
+ if((i1&i)==0) { /* x is integral */
+ u_int32_t high;
+ *iptr = x;
+ GET_HIGH_WORD(high,x);
+ INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */
+ return x;
+ } else {
+ INSERT_WORDS(*iptr,i0,i1&(~i));
+ return x - *iptr;
+ }
+ }
+}
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