1// Copyright 2011 the V8 project authors. All rights reserved.
2// Redistribution and use in source and binary forms, with or without
3// modification, are permitted provided that the following conditions are
4// met:
5//
6//     * Redistributions of source code must retain the above copyright
7//       notice, this list of conditions and the following disclaimer.
8//     * Redistributions in binary form must reproduce the above
9//       copyright notice, this list of conditions and the following
10//       disclaimer in the documentation and/or other materials provided
11//       with the distribution.
12//     * Neither the name of Google Inc. nor the names of its
13//       contributors may be used to endorse or promote products derived
14//       from this software without specific prior written permission.
15//
16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28// Extra POSIX/ANSI routines for Win32 when using Visual Studio C++. Please
29// refer to The Open Group Base Specification for specification of the correct
30// semantics for these functions.
31// (http://www.opengroup.org/onlinepubs/000095399/)
32#ifdef _MSC_VER
33
34#undef V8_WIN32_LEAN_AND_MEAN
35#define V8_WIN32_HEADERS_FULL
36#include "win32-headers.h"
37#include <limits.h>        // Required for INT_MAX etc.
38#include <math.h>
39#include <float.h>         // Required for DBL_MAX and on Win32 for finite()
40#include "win32-math.h"
41
42#include "checks.h"
43
44namespace v8 {
45
46// Test for finite value - usually defined in math.h
47int isfinite(double x) {
48  return _finite(x);
49}
50
51}  // namespace v8
52
53
54// Test for a NaN (not a number) value - usually defined in math.h
55int isnan(double x) {
56  return _isnan(x);
57}
58
59
60// Test for infinity - usually defined in math.h
61int isinf(double x) {
62  return (_fpclass(x) & (_FPCLASS_PINF | _FPCLASS_NINF)) != 0;
63}
64
65
66// Test if x is less than y and both nominal - usually defined in math.h
67int isless(double x, double y) {
68  return isnan(x) || isnan(y) ? 0 : x < y;
69}
70
71
72// Test if x is greater than y and both nominal - usually defined in math.h
73int isgreater(double x, double y) {
74  return isnan(x) || isnan(y) ? 0 : x > y;
75}
76
77
78// Classify floating point number - usually defined in math.h
79int fpclassify(double x) {
80  // Use the MS-specific _fpclass() for classification.
81  int flags = _fpclass(x);
82
83  // Determine class. We cannot use a switch statement because
84  // the _FPCLASS_ constants are defined as flags.
85  if (flags & (_FPCLASS_PN | _FPCLASS_NN)) return FP_NORMAL;
86  if (flags & (_FPCLASS_PZ | _FPCLASS_NZ)) return FP_ZERO;
87  if (flags & (_FPCLASS_PD | _FPCLASS_ND)) return FP_SUBNORMAL;
88  if (flags & (_FPCLASS_PINF | _FPCLASS_NINF)) return FP_INFINITE;
89
90  // All cases should be covered by the code above.
91  ASSERT(flags & (_FPCLASS_SNAN | _FPCLASS_QNAN));
92  return FP_NAN;
93}
94
95
96// Test sign - usually defined in math.h
97int signbit(double x) {
98  // We need to take care of the special case of both positive
99  // and negative versions of zero.
100  if (x == 0)
101    return _fpclass(x) & _FPCLASS_NZ;
102  else
103    return x < 0;
104}
105
106#endif  // _MSC_VER
107