Imported Upstream version 1.49.0upstream/1.49.0

1 files changed, 100 insertions, 0 deletions

diff --git a/boost/numeric/interval/detail/msvc_rounding_control.hpp b/boost/numeric/interval/detail/msvc_rounding_control.hpp
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+++ b/boost/numeric/interval/detail/msvc_rounding_control.hpp
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+/* Boost interval/detail/msvc_rounding_control.hpp file
+ *
+ * Copyright 2000 Maarten Keijzer
+ * Copyright 2002 Hervé Brönnimann, Guillaume Melquiond, Sylvain Pion
+ *
+ * Distributed under the Boost Software License, Version 1.0.
+ * (See accompanying file LICENSE_1_0.txt or
+ * copy at http://www.boost.org/LICENSE_1_0.txt)
+ */
+
+#ifndef BOOST_NUMERIC_INTERVAL_DETAIL_MSVC_ROUNDING_CONTROL_HPP
+#define BOOST_NUMERIC_INTERVAL_DETAIL_MSVC_ROUNDING_CONTROL_HPP
+
+#ifndef _MSC_VER
+#  error This header is only intended for MSVC, but might work for Borland as well
+#endif
+
+#include <float.h>      // MSVC rounding control
+
+// Although the function is called _control87, it seems to work for
+// other FPUs too, so it does not have to be changed to _controlfp.
+
+namespace boost {
+namespace numeric {
+namespace interval_lib {
+namespace detail {
+
+#if BOOST_MSVC < 1400 || defined(WIN64)
+extern "C" { double rint(double); }
+#else
+inline double rint(double x)
+{
+_asm FLD [x] ;
+_asm FRNDINT ;
+//_asm RET ;
+}
+#endif
+
+struct x86_rounding
+{
+  static unsigned int hard2msvc(unsigned short m) {
+    unsigned int n = 0;
+    if (m & 0x01) n |= _EM_INVALID;
+    if (m & 0x02) n |= _EM_DENORMAL;
+    if (m & 0x04) n |= _EM_ZERODIVIDE;
+    if (m & 0x08) n |= _EM_OVERFLOW;
+    if (m & 0x10) n |= _EM_UNDERFLOW;
+    if (m & 0x20) n |= _EM_INEXACT;
+    switch (m & 0x300) {
+    case 0x000: n |= _PC_24; break;
+    case 0x200: n |= _PC_53; break;
+    case 0x300: n |= _PC_64; break;
+    }
+    switch (m & 0xC00) {
+    case 0x000: n |= _RC_NEAR; break;
+    case 0x400: n |= _RC_DOWN; break;
+    case 0x800: n |= _RC_UP;   break;
+    case 0xC00: n |= _RC_CHOP; break;
+    }
+    if (m & 0x1000) n |= _IC_AFFINE; // only useful on 287
+    return n;
+  }
+
+  static unsigned short msvc2hard(unsigned int n) {
+    unsigned short m = 0;
+    if (n & _EM_INVALID)    m |= 0x01;
+    if (n & _EM_DENORMAL)   m |= 0x02;
+    if (n & _EM_ZERODIVIDE) m |= 0x04;
+    if (n & _EM_OVERFLOW)   m |= 0x08;
+    if (n & _EM_UNDERFLOW)  m |= 0x10;
+    if (n & _EM_INEXACT)    m |= 0x20;
+    switch (n & _MCW_RC) {
+    case _RC_NEAR: m |= 0x000; break;
+    case _RC_DOWN: m |= 0x400; break;
+    case _RC_UP:   m |= 0x800; break;
+    case _RC_CHOP: m |= 0xC00; break;
+    }
+    switch (n & _MCW_PC) {
+    case _PC_24: m |= 0x000; break;
+    case _PC_53: m |= 0x200; break;
+    case _PC_64: m |= 0x300; break;
+    }
+    if ((n & _MCW_IC) == _IC_AFFINE) m |= 0x1000;
+    return m;
+  }
+
+  typedef unsigned short rounding_mode;
+  static void get_rounding_mode(rounding_mode& mode)
+  { mode = msvc2hard(_control87(0, 0)); }
+  static void set_rounding_mode(const rounding_mode mode)
+  { _control87(hard2msvc(mode), _MCW_EM | _MCW_RC | _MCW_PC | _MCW_IC); }
+  static double to_int(const double& x) { return rint(x); }
+};
+
+} // namespace detail
+} // namespace interval_lib
+} // namespace numeric
+} // namespace boost
+
+#endif /* BOOST_NUMERIC_INTERVAL_DETAIL_MSVC_ROUNDING_CONTROL_HPP */