• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // -*- C++ -*-
2 //===----------------------- support/win32/support.h ----------------------===//
3 //
4 //                     The LLVM Compiler Infrastructure
5 //
6 // This file is dual licensed under the MIT and the University of Illinois Open
7 // Source Licenses. See LICENSE.TXT for details.
8 //
9 //===----------------------------------------------------------------------===//
10 
11 #ifndef _LIBCPP_SUPPORT_WIN32_SUPPORT_H
12 #define _LIBCPP_SUPPORT_WIN32_SUPPORT_H
13 
14 /*
15    Functions and constants used in libc++ that are missing from the Windows C library.
16   */
17 
18 #include <__config>
19 #include <wchar.h>  // mbstate_t
20 #include <stdio.h> // _snwprintf
21 #define swprintf _snwprintf
22 #define vswprintf _vsnwprintf
23 #define vfscnaf fscanf
24 
25 int vasprintf( char **sptr, const char *__restrict fmt , va_list ap );
26 int asprintf( char **sptr, const char *__restrict fmt, ...);
27 //int vfscanf( FILE *__restrict stream, const char *__restrict format,
28 //             va_list arg);
29 
30 size_t mbsnrtowcs( wchar_t *__restrict dst, const char **__restrict src,
31                    size_t nmc, size_t len, mbstate_t *__restrict ps );
32 size_t wcsnrtombs( char *__restrict dst, const wchar_t **__restrict src,
33                    size_t nwc, size_t len, mbstate_t *__restrict ps );
34 
35 #if defined(_MSC_VER)
36 #define snprintf _snprintf
37 
38 #include <xlocinfo.h>
39 #define atoll _atoi64
40 #define strtoll _strtoi64
41 #define strtoull _strtoui64
42 #define wcstoll _wcstoi64
43 #define wcstoull _wcstoui64
strtof(const char * nptr,char ** endptr)44 _LIBCPP_ALWAYS_INLINE float strtof( const char *nptr, char **endptr )
45 { return _Stof(nptr, endptr, 0); }
strtod(const char * nptr,char ** endptr)46 _LIBCPP_ALWAYS_INLINE double strtod( const char *nptr, char **endptr )
47 { return _Stod(nptr, endptr, 0); }
strtold(const char * nptr,char ** endptr)48 _LIBCPP_ALWAYS_INLINE long double strtold( const char *nptr, char **endptr )
49 { return _Stold(nptr, endptr, 0); }
50 
51 #define _Exit _exit
52 
53 #ifndef __clang__ // MSVC-based Clang also defines _MSC_VER
54 #include <intrin.h>
55 
__builtin_popcount(unsigned int x)56 _LIBCPP_ALWAYS_INLINE int __builtin_popcount(unsigned int x) {
57    static const unsigned int m1 = 0x55555555; //binary: 0101...
58    static const unsigned int m2 = 0x33333333; //binary: 00110011..
59    static const unsigned int m4 = 0x0f0f0f0f; //binary:  4 zeros,  4 ones ...
60    static const unsigned int h01= 0x01010101; //the sum of 256 to the power of 0,1,2,3...
61    x -= (x >> 1) & m1;             //put count of each 2 bits into those 2 bits
62    x = (x & m2) + ((x >> 2) & m2); //put count of each 4 bits into those 4 bits
63    x = (x + (x >> 4)) & m4;        //put count of each 8 bits into those 8 bits
64    return (x * h01) >> 24;  //returns left 8 bits of x + (x<<8) + (x<<16) + (x<<24)
65 }
66 
__builtin_popcountl(unsigned long x)67 _LIBCPP_ALWAYS_INLINE int __builtin_popcountl(unsigned long x) {
68   return __builtin_popcount(static_cast<int>(x));
69 }
70 
__builtin_popcountll(unsigned long long x)71 _LIBCPP_ALWAYS_INLINE int __builtin_popcountll(unsigned long long x) {
72    static const unsigned long long m1  = 0x5555555555555555; //binary: 0101...
73    static const unsigned long long m2  = 0x3333333333333333; //binary: 00110011..
74    static const unsigned long long m4  = 0x0f0f0f0f0f0f0f0f; //binary:  4 zeros,  4 ones ...
75    static const unsigned long long h01 = 0x0101010101010101; //the sum of 256 to the power of 0,1,2,3...
76    x -= (x >> 1) & m1;             //put count of each 2 bits into those 2 bits
77    x = (x & m2) + ((x >> 2) & m2); //put count of each 4 bits into those 4 bits
78    x = (x + (x >> 4)) & m4;        //put count of each 8 bits into those 8 bits
79    return static_cast<int>((x * h01)>>56);  //returns left 8 bits of x + (x<<8) + (x<<16) + (x<<24) + ...
80 }
81 
__builtin_ctz(unsigned int x)82 _LIBCPP_ALWAYS_INLINE int __builtin_ctz( unsigned int x )
83 {
84    DWORD r = 0;
85    _BitScanReverse(&r, x);
86    return static_cast<int>(r);
87 }
88 // sizeof(long) == sizeof(int) on Windows
__builtin_ctzl(unsigned long x)89 _LIBCPP_ALWAYS_INLINE int __builtin_ctzl( unsigned long x )
90 { return __builtin_ctz( static_cast<int>(x) ); }
__builtin_ctzll(unsigned long long x)91 _LIBCPP_ALWAYS_INLINE int __builtin_ctzll( unsigned long long x )
92 {
93     DWORD r = 0;
94     _BitScanReverse64(&r, x);
95     return static_cast<int>(r);
96 }
__builtin_clz(unsigned int x)97 _LIBCPP_ALWAYS_INLINE int __builtin_clz( unsigned int x )
98 {
99    DWORD r = 0;
100    _BitScanForward(&r, x);
101    return static_cast<int>(r);
102 }
103 // sizeof(long) == sizeof(int) on Windows
__builtin_clzl(unsigned long x)104 _LIBCPP_ALWAYS_INLINE int __builtin_clzl( unsigned long x )
105 { return __builtin_clz( static_cast<int>(x) ); }
__builtin_clzll(unsigned long long x)106 _LIBCPP_ALWAYS_INLINE int __builtin_clzll( unsigned long long x )
107 {
108     DWORD r = 0;
109     _BitScanForward64(&r, x);
110     return static_cast<int>(r);
111 }
112 #endif // !__clang__
113 #endif // _MSC_VER
114 
115 #endif // _LIBCPP_SUPPORT_WIN32_SUPPORT_H
116