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 // Copyright 2011 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. // Extra POSIX/ANSI routines for Win32 when using Visual Studio C++. Please // refer to The Open Group Base Specification for specification of the correct // semantics for these functions. // (http://www.opengroup.org/onlinepubs/000095399/) #if defined(_MSC_VER) && (_MSC_VER < 1800) #include "src/base/win32-headers.h" #include // Required for INT_MAX etc. #include // Required for DBL_MAX and on Win32 for finite() #include #include "src/win32-math.h" #include "src/checks.h" namespace std { // Test for a NaN (not a number) value - usually defined in math.h int isnan(double x) { return _isnan(x); } // Test for infinity - usually defined in math.h int isinf(double x) { return (_fpclass(x) & (_FPCLASS_PINF | _FPCLASS_NINF)) != 0; } // Test for finite value - usually defined in math.h int isfinite(double x) { return _finite(x); } // Test if x is less than y and both nominal - usually defined in math.h int isless(double x, double y) { return isnan(x) || isnan(y) ? 0 : x < y; } // Test if x is greater than y and both nominal - usually defined in math.h int isgreater(double x, double y) { return isnan(x) || isnan(y) ? 0 : x > y; } // Classify floating point number - usually defined in math.h int fpclassify(double x) { // Use the MS-specific _fpclass() for classification. int flags = _fpclass(x); // Determine class. We cannot use a switch statement because // the _FPCLASS_ constants are defined as flags. if (flags & (_FPCLASS_PN | _FPCLASS_NN)) return FP_NORMAL; if (flags & (_FPCLASS_PZ | _FPCLASS_NZ)) return FP_ZERO; if (flags & (_FPCLASS_PD | _FPCLASS_ND)) return FP_SUBNORMAL; if (flags & (_FPCLASS_PINF | _FPCLASS_NINF)) return FP_INFINITE; // All cases should be covered by the code above. ASSERT(flags & (_FPCLASS_SNAN | _FPCLASS_QNAN)); return FP_NAN; } // Test sign - usually defined in math.h int signbit(double x) { // We need to take care of the special case of both positive // and negative versions of zero. if (x == 0) return _fpclass(x) & _FPCLASS_NZ; else return x < 0; } } // namespace std #endif // _MSC_VER