Crypto++  8.2
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 // C1189: error: This header is specific to ARM targets
18 #if (CRYPTOPP_ARM_NEON_AVAILABLE) && !defined(_M_ARM64)
19 # include <arm_neon.h>
20 #endif
21 
22 #if (CRYPTOPP_ARM_ACLE_AVAILABLE)
23 # include <stdint.h>
24 # include <arm_acle.h>
25 #endif
26 
27 #ifdef CRYPTOPP_GNU_STYLE_INLINE_ASSEMBLY
28 # include <signal.h>
29 # include <setjmp.h>
30 #endif
31 
32 #ifndef EXCEPTION_EXECUTE_HANDLER
33 # define EXCEPTION_EXECUTE_HANDLER 1
34 #endif
35 
36 // Squash MS LNK4221 and libtool warnings
37 extern const char CRC_SIMD_FNAME[] = __FILE__;
38 
39 NAMESPACE_BEGIN(CryptoPP)
40 
41 #ifdef CRYPTOPP_GNU_STYLE_INLINE_ASSEMBLY
42 extern "C" {
43  typedef void (*SigHandler)(int);
44 
45  static jmp_buf s_jmpSIGILL;
46  static void SigIllHandler(int)
47  {
48  longjmp(s_jmpSIGILL, 1);
49  }
50 }
51 #endif // Not CRYPTOPP_MS_STYLE_INLINE_ASSEMBLY
52 
53 #if (CRYPTOPP_BOOL_ARM32 || CRYPTOPP_BOOL_ARMV8)
54 
55 bool CPU_ProbeCRC32()
56 {
57 #if defined(CRYPTOPP_NO_CPU_FEATURE_PROBES)
58  return false;
59 #elif (CRYPTOPP_ARM_CRC32_AVAILABLE)
60 # if defined(CRYPTOPP_MS_STYLE_INLINE_ASSEMBLY)
61  volatile bool result = true;
62  __try
63  {
64  word32 w=0, x=1; word16 y=2; byte z=3;
65  w = __crc32w(w,x);
66  w = __crc32h(w,y);
67  w = __crc32b(w,z);
68  w = __crc32cw(w,x);
69  w = __crc32ch(w,y);
70  w = __crc32cb(w,z);
71 
72  result = !!w;
73  }
74  __except (EXCEPTION_EXECUTE_HANDLER)
75  {
76  return false;
77  }
78  return result;
79 #else
80 
81  // longjmp and clobber warnings. Volatile is required.
82  // http://github.com/weidai11/cryptopp/issues/24 and http://stackoverflow.com/q/7721854
83  volatile bool result = true;
84 
85  volatile SigHandler oldHandler = signal(SIGILL, SigIllHandler);
86  if (oldHandler == SIG_ERR)
87  return false;
88 
89  volatile sigset_t oldMask;
90  if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
91  return false;
92 
93  if (setjmp(s_jmpSIGILL))
94  result = false;
95  else
96  {
97  word32 w=0, x=1; word16 y=2; byte z=3;
98  w = __crc32w(w,x);
99  w = __crc32h(w,y);
100  w = __crc32b(w,z);
101  w = __crc32cw(w,x);
102  w = __crc32ch(w,y);
103  w = __crc32cb(w,z);
104 
105  // Hack... GCC optimizes away the code and returns true
106  result = !!w;
107  }
108 
109  sigprocmask(SIG_SETMASK, (sigset_t*)&oldMask, NULLPTR);
110  signal(SIGILL, oldHandler);
111  return result;
112 # endif
113 #else
114  return false;
115 #endif // CRYPTOPP_ARM_CRC32_AVAILABLE
116 }
117 #endif // ARM32 or ARM64
118 
119 #if (CRYPTOPP_ARM_CRC32_AVAILABLE)
120 void CRC32_Update_ARMV8(const byte *s, size_t n, word32& c)
121 {
122  for(; !IsAligned<word32>(s) && n > 0; s++, n--)
123  c = __crc32b(c, *s);
124 
125  for(; n > 4; s+=4, n-=4)
126  c = __crc32w(c, *(const word32 *)(void*)s);
127 
128  for(; n > 0; s++, n--)
129  c = __crc32b(c, *s);
130 }
131 
132 void CRC32C_Update_ARMV8(const byte *s, size_t n, word32& c)
133 {
134  for(; !IsAligned<word32>(s) && n > 0; s++, n--)
135  c = __crc32cb(c, *s);
136 
137  for(; n > 4; s+=4, n-=4)
138  c = __crc32cw(c, *(const word32 *)(void*)s);
139 
140  for(; n > 0; s++, n--)
141  c = __crc32cb(c, *s);
142 }
143 #endif
144 
145 #if (CRYPTOPP_SSE42_AVAILABLE)
146 void CRC32C_Update_SSE42(const byte *s, size_t n, word32& c)
147 {
148  for(; !IsAligned<word32>(s) && n > 0; s++, n--)
149  c = _mm_crc32_u8(c, *s);
150 
151  for(; n > 4; s+=4, n-=4)
152  c = _mm_crc32_u32(c, *(const word32 *)(void*)s);
153 
154  for(; n > 0; s++, n--)
155  c = _mm_crc32_u8(c, *s);
156 }
157 #endif
158 
159 NAMESPACE_END
Utility functions for the Crypto++ library.
Library configuration file.
Precompiled header file.
Crypto++ library namespace.