set default newlib dir's structure

git-svn-id: svn://kolibrios.org@4874 a494cfbc-eb01-0410-851d-a64ba20cac60
2014-04-22 09:02:02 +00:00
parent 47fd2fdc08
commit 846fce0120
651 changed files with 0 additions and 0 deletions
--- a/contrib/sdk/sources/newlib/libc/math/s_trunc.c
+++ b/contrib/sdk/sources/newlib/libc/math/s_trunc.c
@@ -0,0 +1,98 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+/*
+FUNCTION
+<<trunc>>, <<truncf>>--round to integer, towards zero
+INDEX
+	trunc
+INDEX
+	truncf
+
+ANSI_SYNOPSIS
+	#include <math.h>
+	double trunc(double <[x]>);
+	float truncf(float <[x]>);
+
+DESCRIPTION
+	The <<trunc>> functions round their argument to the integer value, in
+	floating format, nearest to but no larger in magnitude than the
+	argument, regardless of the current rounding direction.  (While the
+	"inexact" floating-point exception behavior is unspecified by the C
+	standard, the <<trunc>> functions are written so that "inexact" is not
+	raised if the result does not equal the argument, which behavior is as
+	recommended by IEEE 754 for its related functions.)
+
+RETURNS
+<[x]> truncated to an integral value.
+
+PORTABILITY
+ANSI C, POSIX
+
+*/
+
+#include "fdlibm.h"
+
+#ifndef _DOUBLE_IS_32BITS
+
+#ifdef __STDC__
+	double trunc(double x)
+#else
+	double trunc(x)
+	double x;
+#endif
+{
+  int signbit;
+  /* Most significant word, least significant word. */
+  int msw;
+  unsigned int lsw;
+  int exponent_less_1023;
+
+  EXTRACT_WORDS(msw, lsw, x);
+
+  /* Extract sign bit. */
+  signbit = msw & 0x80000000;
+
+  /* Extract exponent field. */
+  exponent_less_1023 = ((msw & 0x7ff00000) >> 20) - 1023;
+
+  if (exponent_less_1023 < 20)
+    {
+      /* All significant digits are in msw. */
+      if (exponent_less_1023 < 0)
+        {
+          /* -1 < x < 1, so result is +0 or -0. */
+          INSERT_WORDS(x, signbit, 0);
+        }
+      else
+        {
+          /* All relevant fraction bits are in msw, so lsw of the result is 0. */
+          INSERT_WORDS(x, signbit | (msw & ~(0x000fffff >> exponent_less_1023)), 0);
+        }
+    }
+  else if (exponent_less_1023 > 51)
+    {
+      if (exponent_less_1023 == 1024)
+        {
+          /* x is infinite, or not a number, so trigger an exception. */
+          return x + x;
+        }
+      /* All bits in the fraction fields of the msw and lsw are needed in the result. */
+    }
+  else
+    {
+      /* All fraction bits in msw are relevant.  Truncate irrelevant
+         bits from lsw. */
+      INSERT_WORDS(x, msw, lsw & ~(0xffffffffu >> (exponent_less_1023 - 20)));
+    }
+  return x;
+}
+
+#endif /* _DOUBLE_IS_32BITS */