Crypto++  8.5
Free C++ class library of cryptographic schemes
crc_simd.cpp
1 // crc_simd.cpp - written and placed in the public domain by
2 // Jeffrey Walton, Uri Blumenthal and Marcel Raad.
3 //
4 // This source file uses intrinsics to gain access to SSE4.2 and
5 // ARMv8a CRC-32 and CRC-32C instructions. A separate source file
6 // is needed because additional CXXFLAGS are required to enable
7 // the appropriate instructions sets in some build configurations.
8 
9 #include "pch.h"
10 #include "config.h"
11 #include "misc.h"
12 
13 #if (CRYPTOPP_SSE42_AVAILABLE)
14 # include <nmmintrin.h>
15 #endif
16 
17 #if (CRYPTOPP_ARM_NEON_HEADER)
18 # include <arm_neon.h>
19 #endif
20 
21 #if (CRYPTOPP_ARM_ACLE_HEADER)
22 # include <stdint.h>
23 # include <arm_acle.h>
24 #endif
25 
26 #ifdef CRYPTOPP_GNU_STYLE_INLINE_ASSEMBLY
27 # include <signal.h>
28 # include <setjmp.h>
29 #endif
30 
31 #ifndef EXCEPTION_EXECUTE_HANDLER
32 # define EXCEPTION_EXECUTE_HANDLER 1
33 #endif
34 
35 // Squash MS LNK4221 and libtool warnings
36 extern const char CRC_SIMD_FNAME[] = __FILE__;
37 
38 NAMESPACE_BEGIN(CryptoPP)
39 
40 #ifdef CRYPTOPP_GNU_STYLE_INLINE_ASSEMBLY
41 extern "C" {
42  typedef void (*SigHandler)(int);
43 
44  static jmp_buf s_jmpSIGILL;
45  static void SigIllHandler(int)
46  {
47  longjmp(s_jmpSIGILL, 1);
48  }
49 }
50 #endif // Not CRYPTOPP_MS_STYLE_INLINE_ASSEMBLY
51 
52 #if (CRYPTOPP_BOOL_ARM32 || CRYPTOPP_BOOL_ARMV8)
53 
54 bool CPU_ProbeCRC32()
55 {
56 #if defined(CRYPTOPP_NO_CPU_FEATURE_PROBES)
57  return false;
58 #elif (CRYPTOPP_ARM_CRC32_AVAILABLE)
59 # if defined(CRYPTOPP_MS_STYLE_INLINE_ASSEMBLY)
60  volatile bool result = true;
61  __try
62  {
63  word32 w=0, x=1; word16 y=2; byte z=3;
64  w = __crc32w(w,x);
65  w = __crc32h(w,y);
66  w = __crc32b(w,z);
67  w = __crc32cw(w,x);
68  w = __crc32ch(w,y);
69  w = __crc32cb(w,z);
70 
71  result = !!w;
72  }
73  __except (EXCEPTION_EXECUTE_HANDLER)
74  {
75  return false;
76  }
77  return result;
78 #else
79 
80  // longjmp and clobber warnings. Volatile is required.
81  // http://github.com/weidai11/cryptopp/issues/24 and http://stackoverflow.com/q/7721854
82  volatile bool result = true;
83 
84  volatile SigHandler oldHandler = signal(SIGILL, SigIllHandler);
85  if (oldHandler == SIG_ERR)
86  return false;
87 
88  volatile sigset_t oldMask;
89  if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
90  {
91  signal(SIGILL, oldHandler);
92  return false;
93  }
94 
95  if (setjmp(s_jmpSIGILL))
96  result = false;
97  else
98  {
99  word32 w=0, x=1; word16 y=2; byte z=3;
100  w = __crc32w(w,x);
101  w = __crc32h(w,y);
102  w = __crc32b(w,z);
103  w = __crc32cw(w,x);
104  w = __crc32ch(w,y);
105  w = __crc32cb(w,z);
106 
107  // Hack... GCC optimizes away the code and returns true
108  result = !!w;
109  }
110 
111  sigprocmask(SIG_SETMASK, (sigset_t*)&oldMask, NULLPTR);
112  signal(SIGILL, oldHandler);
113  return result;
114 # endif
115 #else
116  return false;
117 #endif // CRYPTOPP_ARM_CRC32_AVAILABLE
118 }
119 #endif // ARM32 or ARM64
120 
121 #if (CRYPTOPP_ARM_CRC32_AVAILABLE)
122 void CRC32_Update_ARMV8(const byte *s, size_t n, word32& c)
123 {
124  for(; !IsAligned<word32>(s) && n > 0; s++, n--)
125  c = __crc32b(c, *s);
126 
127  for(; n > 4; s+=4, n-=4)
128  c = __crc32w(c, *(const word32 *)(void*)s);
129 
130  for(; n > 0; s++, n--)
131  c = __crc32b(c, *s);
132 }
133 
134 void CRC32C_Update_ARMV8(const byte *s, size_t n, word32& c)
135 {
136  for(; !IsAligned<word32>(s) && n > 0; s++, n--)
137  c = __crc32cb(c, *s);
138 
139  for(; n > 4; s+=4, n-=4)
140  c = __crc32cw(c, *(const word32 *)(void*)s);
141 
142  for(; n > 0; s++, n--)
143  c = __crc32cb(c, *s);
144 }
145 #endif
146 
147 #if (CRYPTOPP_SSE42_AVAILABLE)
148 void CRC32C_Update_SSE42(const byte *s, size_t n, word32& c)
149 {
150  for(; !IsAligned<word32>(s) && n > 0; s++, n--)
151  c = _mm_crc32_u8(c, *s);
152 
153  for(; n > 4; s+=4, n-=4)
154  c = _mm_crc32_u32(c, *(const word32 *)(void*)s);
155 
156  for(; n > 0; s++, n--)
157  c = _mm_crc32_u8(c, *s);
158 }
159 #endif
160 
161 NAMESPACE_END
Library configuration file.
unsigned int word32
32-bit unsigned datatype
Definition: config_int.h:62
unsigned short word16
16-bit unsigned datatype
Definition: config_int.h:59
Utility functions for the Crypto++ library.
Crypto++ library namespace.
Precompiled header file.