Crypto++ 8.1 Free C++ class library of cryptographic schemes

Macros
cpu.h File Reference

Functions for CPU features and intrinsics. More...

Go to the source code of this file.

## Macros
#define | NEW_LINE
#define | INTEL_PREFIX
#define | INTEL_NOPREFIX
#define | ATT_PREFIX
#define | ATT_NOPREFIX
#define | CRYPTOPP_CPUID_AVAILABLE 1

## Functions
IA-32 CPU FEATURES
bool | HasSSE2 ()
| Determines SSE2 availability. More...
bool | HasSSSE3 ()
| Determines SSSE3 availability. More...
bool | HasSSE41 ()
| Determines SSE4.1 availability. More...
bool | HasSSE42 ()
| Determines SSE4.2 availability. More...
bool | HasAESNI ()
| Determines AES-NI availability. More...
bool | HasCLMUL ()
| Determines Carryless Multiply availability. More...
bool | HasSHA ()
| Determines SHA availability. More...
bool | HasADX ()
| Determines ADX availability. More...
bool | HasAVX ()
| Determines AVX availability. More...
bool | HasAVX2 ()
| Determines AVX2 availability. More...
bool | IsP4 ()
| Determines if the CPU is an Intel P4. More...
bool | HasRDRAND ()
| Determines RDRAND availability. More...
bool | HasRDSEED ()
| Determines RDSEED availability. More...
bool | HasPadlockRNG ()
| Determines Padlock RNG availability. More...
bool | HasPadlockACE ()
| Determines Padlock ACE availability. More...
bool | HasPadlockACE2 ()
| Determines Padlock ACE2 availability. More...
bool | HasPadlockPHE ()
| Determines Padlock PHE availability. More...
bool | HasPadlockPMM ()
| Determines Padlock PMM availability. More...
int | GetCacheLineSize ()
| Provides the cache line size. More...
ARM A-32, Aarch32 and AArch64 CPU FEATURES
bool | HasARMv7 ()
| Determine if an ARM processor is ARMv7 or above. More...
bool | HasNEON ()
| Determine if an ARM processor has Advanced SIMD available. More...
bool | HasPMULL ()
| Determine if an ARM processor provides Polynomial Multiplication. More...
bool | HasCRC32 ()
| Determine if an ARM processor has CRC32 available. More...
bool | HasAES ()
| Determine if an ARM processor has AES available. More...
bool | HasSHA1 ()
| Determine if an ARM processor has SHA1 available. More...
bool | HasSHA2 ()
| Determine if an ARM processor has SHA256 available. More...
bool | HasSHA512 ()
| Determine if an ARM processor has SHA512 available. More...
bool | HasSHA3 ()
| Determine if an ARM processor has SHA3 available. More...
bool | HasSM3 ()
| Determine if an ARM processor has SM3 available. More...
bool | HasSM4 ()
| Determine if an ARM processor has SM4 available. More...
POWERPC CPU FEATURES
bool | HasAltivec ()
| Determine if a PowerPC processor has Altivec available. More...
bool | HasPower7 ()
| Determine if a PowerPC processor has Power7 available. More...
bool | HasPower8 ()
| Determine if a PowerPC processor has Power8 available. More...
bool | HasPower9 ()
| Determine if a PowerPC processor has Power9 available. More...
bool | HasSHA256 ()
| Determine if a PowerPC processor has SHA256 available. More...
bool | HasDARN ()
| Determine if a PowerPC processor has DARN available. More...

## Detailed Description

Functions for CPU features and intrinsics.

The CPU functions are used in IA-32, ARM and PowerPC code paths. The functions provide cpu specific feature testing on IA-32, ARM and PowerPC machines.

Feature detection uses CPUID on IA-32, like Intel and AMD. On other platforms a two-part strategy is used. First, the library attempts to *Query* the OS for a feature, like using Linux getauxval() or android_getCpuFeatures(). If that fails, then *Probe* the cpu executing an instruction and an observe a SIGILL if unsupported. The general pattern used by the library is:

        g_hasCRC32 = CPU_QueryCRC32() || CPU_ProbeCRC32();
        g_hasPMULL = CPU_QueryPMULL() || CPU_ProbePMULL();
        g_hasAES  = CPU_QueryAES() || CPU_ProbeAES();

Generally speaking, CPU_Query() is in the source file `cpu.cpp` because it does not require special architectural flags. CPU_Probe() is in a source file that recieves architectural flags, like `sse_simd.cpp`, `neon_simd.cpp` and `ppc_simd.cpp`. For example, compiling `neon_simd.cpp` on an ARM64 machine will have `-march=armv8-a` applied during a compile to make the instruction set architecture (ISA) available.

The cpu probes are expensive when compared to a standard OS feature query. The library also avoids probes on Apple platforms because Apple's signal handling for SIGILLs appears to corrupt memory. CPU_Probe() will unconditionally return false for Apple platforms. OpenSSL experienced the same problem and moved away from SIGILL probes on Apple.

Definition in file cpu.h.

## Function Documentation

## ◆ HasSSE2()

bool HasSSE2 | ( |  | ) |
| inline

Determines SSE2 availability.

Returns
  true if SSE2 is determined to be available, false otherwise

MMX, SSE and SSE2 are core processor features for x86_64, and the function always returns true for the platform.

Note
  This function is only available on Intel IA-32 platforms

Definition at line 116 of file cpu.h.

## ◆ HasSSSE3()

bool HasSSSE3 | ( |  | ) |
| inline

Determines SSSE3 availability.

Returns
  true if SSSE3 is determined to be available, false otherwise

HasSSSE3() is a runtime check performed using CPUID

Note
  This function is only available on Intel IA-32 platforms

Definition at line 131 of file cpu.h.

## ◆ HasSSE41()

bool HasSSE41 | ( |  | ) |
| inline

Determines SSE4.1 availability.

Returns
  true if SSE4.1 is determined to be available, false otherwise

HasSSE41() is a runtime check performed using CPUID

Note
  This function is only available on Intel IA-32 platforms

Definition at line 142 of file cpu.h.

## ◆ HasSSE42()

bool HasSSE42 | ( |  | ) |
| inline

Determines SSE4.2 availability.

Returns
  true if SSE4.2 is determined to be available, false otherwise

HasSSE42() is a runtime check performed using CPUID

Note
  This function is only available on Intel IA-32 platforms

Definition at line 153 of file cpu.h.

## ◆ HasAESNI()

bool HasAESNI | ( |  | ) |
| inline

Determines AES-NI availability.

Returns
  true if AES-NI is determined to be available, false otherwise

HasAESNI() is a runtime check performed using CPUID

Since
  Crypto++ 5.6.1

Note
  This function is only available on Intel IA-32 platforms

Definition at line 165 of file cpu.h.

## ◆ HasCLMUL()

bool HasCLMUL | ( |  | ) |
| inline

Determines Carryless Multiply availability.

Returns
  true if pclmulqdq is determined to be available, false otherwise

HasCLMUL() is a runtime check performed using CPUID

Since
  Crypto++ 5.6.1

Note
  This function is only available on Intel IA-32 platforms

Definition at line 177 of file cpu.h.

## ◆ HasSHA()

bool HasSHA | ( |  | ) |
| inline

Determines SHA availability.

Returns
  true if SHA is determined to be available, false otherwise

HasSHA() is a runtime check performed using CPUID

Since
  Crypto++ 6.0

Note
  This function is only available on Intel IA-32 platforms

Definition at line 189 of file cpu.h.

## ◆ HasADX()

bool HasADX | ( |  | ) |
| inline

Determines ADX availability.

Returns
  true if ADX is determined to be available, false otherwise

HasADX() is a runtime check performed using CPUID

Since
  Crypto++ 7.0

Note
  This function is only available on Intel IA-32 platforms

Definition at line 201 of file cpu.h.

## ◆ HasAVX()

bool HasAVX | ( |  | ) |
| inline

Determines AVX availability.

Returns
  true if AVX is determined to be available, false otherwise

HasAVX() is a runtime check performed using CPUID

Since
  Crypto++ 8.0

Note
  This function is only available on Intel IA-32 platforms

Definition at line 213 of file cpu.h.

## ◆ HasAVX2()

bool HasAVX2 | ( |  | ) |
| inline

Determines AVX2 availability.

Returns
  true if AVX2 is determined to be available, false otherwise

HasAVX2() is a runtime check performed using CPUID

Since
  Crypto++ 8.0

Note
  This function is only available on Intel IA-32 platforms

Definition at line 225 of file cpu.h.

## ◆ IsP4()

bool IsP4 | ( |  | ) |
| inline

Determines if the CPU is an Intel P4.

Returns
  true if the CPU is a P4, false otherwise

IsP4() is a runtime check performed using CPUID

Note
  This function is only available on Intel IA-32 platforms

Definition at line 236 of file cpu.h.

## ◆ HasRDRAND()

bool HasRDRAND | ( |  | ) |
| inline

Determines RDRAND availability.

Returns
  true if RDRAND is determined to be available, false otherwise

HasRDRAND() is a runtime check performed using CPUID

Note
  This function is only available on Intel IA-32 platforms

Definition at line 247 of file cpu.h.

## ◆ HasRDSEED()

bool HasRDSEED | ( |  | ) |
| inline

Determines RDSEED availability.

Returns
  true if RDSEED is determined to be available, false otherwise

HasRDSEED() is a runtime check performed using CPUID

Note
  This function is only available on Intel IA-32 platforms

Definition at line 258 of file cpu.h.

## ◆ HasPadlockRNG()

bool HasPadlockRNG | ( |  | ) |
| inline

Determines Padlock RNG availability.

Returns
  true if VIA Padlock RNG is determined to be available, false otherwise

HasPadlockRNG() is a runtime check performed using CPUID

Note
  This function is only available on Intel IA-32 platforms

Definition at line 269 of file cpu.h.

## ◆ HasPadlockACE()

bool HasPadlockACE | ( |  | ) |
| inline

Determines Padlock ACE availability.

Returns
  true if VIA Padlock ACE is determined to be available, false otherwise

HasPadlockACE() is a runtime check performed using CPUID

Note
  This function is only available on Intel IA-32 platforms

Definition at line 280 of file cpu.h.

## ◆ HasPadlockACE2()

bool HasPadlockACE2 | ( |  | ) |
| inline

Determines Padlock ACE2 availability.

Returns
  true if VIA Padlock ACE2 is determined to be available, false otherwise

HasPadlockACE2() is a runtime check performed using CPUID

Note
  This function is only available on Intel IA-32 platforms

Definition at line 291 of file cpu.h.

## ◆ HasPadlockPHE()

bool HasPadlockPHE | ( |  | ) |
| inline

Determines Padlock PHE availability.

Returns
  true if VIA Padlock PHE is determined to be available, false otherwise

HasPadlockPHE() is a runtime check performed using CPUID

Note
  This function is only available on Intel IA-32 platforms

Definition at line 302 of file cpu.h.

## ◆ HasPadlockPMM()

bool HasPadlockPMM | ( |  | ) |
| inline

Determines Padlock PMM availability.

Returns
  true if VIA Padlock PMM is determined to be available, false otherwise

HasPadlockPMM() is a runtime check performed using CPUID

Note
  This function is only available on Intel IA-32 platforms

Definition at line 313 of file cpu.h.

## ◆ GetCacheLineSize()

int GetCacheLineSize | ( |  | ) |
| inline

Provides the cache line size.

Returns
  lower bound on the size of a cache line in bytes, if available

GetCacheLineSize() returns the lower bound on the size of a cache line, if it is available. If the value is not available at runtime, then 32 is returned for a 32-bit processor and 64 is returned for a 64-bit processor.

x86/x32/x64 uses CPUID to determine the value and it is usually accurate. PowerPC and AIX also makes the value available to user space and it is also usually accurate. The ARM processor equivalent is a privileged instruction, so a compile time value is returned.

Definition at line 328 of file cpu.h.

## ◆ HasARMv7()

bool HasARMv7 | ( |  | ) |
| inline

Determine if an ARM processor is ARMv7 or above.

Returns
  true if the hardware is ARMv7 or above, false otherwise.

Some AES code requires ARMv7 or above

Since
  Crypto++ 8.0

Note
  This function is only available on ARM-32, Aarch32 and Aarch64 platforms

Definition at line 367 of file cpu.h.

## ◆ HasNEON()

bool HasNEON | ( |  | ) |
| inline

Determine if an ARM processor has Advanced SIMD available.

Returns
  true if the hardware is capable of Advanced SIMD at runtime, false otherwise.

Advanced SIMD instructions are available under most ARMv7, Aarch32 and Aarch64.

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-mfpu=neon` (32-bit) or `-march=armv8-a` (64-bit). Also see ARM's `__ARM_NEON` preprocessor macro.

Since
  Crypto++ 5.6.4

Note
  This function is only available on ARM-32, Aarch32 and Aarch64 platforms

Definition at line 387 of file cpu.h.

## ◆ HasPMULL()

bool HasPMULL | ( |  | ) |
| inline

Determine if an ARM processor provides Polynomial Multiplication.

Determine if a PowerPC processor has Polynomial Multiply available.

Returns
  true if the hardware is capable of polynomial multiplications at runtime, false otherwise.

The multiplication instructions are available under Aarch32 and Aarch64.

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-march=armv8-a+crypto`; while Apple requires `-arch arm64`. Also see ARM's `__ARM_FEATURE_CRYPTO` preprocessor macro.

Since
  Crypto++ 5.6.4

Note
  This function is only available on Aarch32 and Aarch64 platforms

Returns
  true if the hardware is capable of PMULL at runtime, false otherwise.

PMULL is part of the in-crypto extensions on Power8 and Power9.

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-mcpu=power8`; while IBM XL C/C++ compilers require `-qarch=pwr8 -qaltivec`. Also see PowerPC's `__CRYPTO` preprocessor macro.

Note
  This function is only available on PowerPC and PowerPC-64 platforms

Definition at line 408 of file cpu.h.

## ◆ HasCRC32()

bool HasCRC32 | ( |  | ) |
| inline

Determine if an ARM processor has CRC32 available.

Returns
  true if the hardware is capable of CRC32 at runtime, false otherwise.

CRC32 instructions provide access to the processor's CRC-32 and CRC-32C instructions. They are provided by ARM C Language Extensions 2.0 (ACLE 2.0) and available under Aarch32 and Aarch64.

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-march=armv8-a+crc`; while Apple requires `-arch arm64`. Also see ARM's `__ARM_FEATURE_CRC32` preprocessor macro.

Since
  Crypto++ 5.6.4

Note
  This function is only available on Aarch32 and Aarch64 platforms

Definition at line 429 of file cpu.h.

## ◆ HasAES()

bool HasAES | ( |  | ) |
| inline

Determine if an ARM processor has AES available.

Determine if a PowerPC processor has AES available.

Returns
  true if the hardware is capable of AES at runtime, false otherwise.

AES is part of the optional Crypto extensions on Aarch32 and Aarch64. They are accessed using ARM C Language Extensions 2.0 (ACLE 2.0).

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-march=armv8-a+crypto`; while Apple requires `-arch arm64`. Also see ARM's `__ARM_FEATURE_CRYPTO` preprocessor macro.

Since
  Crypto++ 5.6.4

Note
  This function is only available on Aarch32 and Aarch64 platforms

Returns
  true if the hardware is capable of AES at runtime, false otherwise.

AES is part of the in-crypto extensions on Power8 and Power9.

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-mcpu=power8`; while IBM XL C/C++ compilers require `-qarch=pwr8 -qaltivec`. Also see PowerPC's `__CRYPTO` preprocessor macro.

Note
  This function is only available on PowerPC and PowerPC-64 platforms

Definition at line 449 of file cpu.h.

## ◆ HasSHA1()

bool HasSHA1 | ( |  | ) |
| inline

Determine if an ARM processor has SHA1 available.

Returns
  true if the hardware is capable of SHA1 at runtime, false otherwise.

SHA1 is part of the optional Crypto extensions on Aarch32 and Aarch64. They are accessed using ARM C Language Extensions 2.0 (ACLE 2.0).

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-march=armv8-a+crypto`; while Apple requires `-arch arm64`. Also see ARM's `__ARM_FEATURE_CRYPTO` preprocessor macro.

Since
  Crypto++ 5.6.4

Note
  This function is only available on Aarch32 and Aarch64 platforms

Definition at line 469 of file cpu.h.

## ◆ HasSHA2()

bool HasSHA2 | ( |  | ) |
| inline

Determine if an ARM processor has SHA256 available.

Returns
  true if the hardware is capable of SHA256 at runtime, false otherwise.

SHA256 is part of the optional Crypto extensions on Aarch32 and Aarch64. They are accessed using ARM C Language Extensions 2.0 (ACLE 2.0).

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-march=armv8-a+crypto`; while Apple requires `-arch arm64`. Also see ARM's `__ARM_FEATURE_CRYPTO` preprocessor macro.

Since
  Crypto++ 5.6.4

Note
  This function is only available on Aarch32 and Aarch64 platforms

Definition at line 489 of file cpu.h.

## ◆ HasSHA512()

bool HasSHA512 | ( |  | ) |
| inline

Determine if an ARM processor has SHA512 available.

Determine if a PowerPC processor has SHA512 available.

Returns
  true if the hardware is capable of SHA512 at runtime, false otherwise.

SHA512 is part of the ARMv8.4 Crypto extensions on Aarch32 and Aarch64. They are accessed using ARM C Language Extensions 2.0 (ACLE 2.0).

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-march=armv8.4-a+crypto`; while Apple requires `-arch arm64`. Also see ARM's `__ARM_FEATURE_CRYPTO` preprocessor macro.

Since
  Crypto++ 8.0

Note
  This function is only available on Aarch32 and Aarch64 platforms

Returns
  true if the hardware is capable of SHA512 at runtime, false otherwise.

SHA is part of the in-crypto extensions on Power8 and Power9.

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-mcpu=power8`; while IBM XL C/C++ compilers require `-qarch=pwr8 -qaltivec`. Also see PowerPC's `__CRYPTO` preprocessor macro.

Note
  This function is only available on PowerPC and PowerPC-64 platforms

Definition at line 509 of file cpu.h.

## ◆ HasSHA3()

bool HasSHA3 | ( |  | ) |
| inline

Determine if an ARM processor has SHA3 available.

Returns
  true if the hardware is capable of SHA3 at runtime, false otherwise.

SHA3 is part of the ARMv8.4 Crypto extensions on Aarch32 and Aarch64. They are accessed using ARM C Language Extensions 2.0 (ACLE 2.0).

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-march=armv8.4-a+crypto`; while Apple requires `-arch arm64`. Also see ARM's `__ARM_FEATURE_CRYPTO` preprocessor macro.

Since
  Crypto++ 8.0

Note
  This function is only available on Aarch32 and Aarch64 platforms

Definition at line 529 of file cpu.h.

## ◆ HasSM3()

bool HasSM3 | ( |  | ) |
| inline

Determine if an ARM processor has SM3 available.

Returns
  true if the hardware is capable of SM3 at runtime, false otherwise.

SM3 is part of the ARMv8.4 Crypto extensions on Aarch32 and Aarch64. They are accessed using ARM C Language Extensions 2.0 (ACLE 2.0).

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-march=armv8.4-a+crypto`; while Apple requires `-arch arm64`. Also see ARM's `__ARM_FEATURE_CRYPTO` preprocessor macro.

Since
  Crypto++ 8.0

Note
  This function is only available on Aarch32 and Aarch64 platforms

Definition at line 549 of file cpu.h.

## ◆ HasSM4()

bool HasSM4 | ( |  | ) |
| inline

Determine if an ARM processor has SM4 available.

Returns
  true if the hardware is capable of SM4 at runtime, false otherwise.

SM4 is part of the ARMv8.4 Crypto extensions on Aarch32 and Aarch64. They are accessed using ARM C Language Extensions 2.0 (ACLE 2.0).

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-march=armv8.4-a+crypto`; while Apple requires `-arch arm64`. Also see ARM's `__ARM_FEATURE_CRYPTO` preprocessor macro.

Since
  Crypto++ 8.0

Note
  This function is only available on Aarch32 and Aarch64 platforms

Definition at line 569 of file cpu.h.

## ◆ HasAltivec()

bool HasAltivec | ( |  | ) |
| inline

Determine if a PowerPC processor has Altivec available.

Returns
  true if the hardware is capable of Altivec at runtime, false otherwise.

Altivec instructions are available on modern PowerPCs.

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-mcpu=power4`; while IBM XL C/C++ compilers require `-qarch=pwr6 -qaltivec`. Also see PowerPC's `_ALTIVEC_` preprocessor macro.

Note
  This function is only available on PowerPC and PowerPC-64 platforms

Definition at line 614 of file cpu.h.

## ◆ HasPower7()

bool HasPower7 | ( |  | ) |
| inline

Determine if a PowerPC processor has Power7 available.

Returns
  true if the hardware is capable of Power7 at runtime, false otherwise.

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-mcpu=power7`; while IBM XL C/C++ compilers require `-qarch=pwr7 -qaltivec`. Also see PowerPC's `_ALTIVEC_` preprocessor macro.

Note
  This function is only available on PowerPC and PowerPC-64 platforms

Definition at line 627 of file cpu.h.

## ◆ HasPower8()

bool HasPower8 | ( |  | ) |
| inline

Determine if a PowerPC processor has Power8 available.

Returns
  true if the hardware is capable of Power8 at runtime, false otherwise.

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-mcpu=power8`; while IBM XL C/C++ compilers require `-qarch=pwr8 -qaltivec`. Also see PowerPC's `_ALTIVEC_` preprocessor macro.

Note
  This function is only available on PowerPC and PowerPC-64 platforms

Definition at line 640 of file cpu.h.

## ◆ HasPower9()

bool HasPower9 | ( |  | ) |
| inline

Determine if a PowerPC processor has Power9 available.

Returns
  true if the hardware is capable of Power9 at runtime, false otherwise.

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-mcpu=power9`; while IBM XL C/C++ compilers require `-qarch=pwr9 -qaltivec`. Also see PowerPC's `_ALTIVEC_` preprocessor macro.

Note
  This function is only available on PowerPC and PowerPC-64 platforms

Definition at line 653 of file cpu.h.

## ◆ HasSHA256()

bool HasSHA256 | ( |  | ) |
| inline

Determine if a PowerPC processor has SHA256 available.

Returns
  true if the hardware is capable of SHA256 at runtime, false otherwise.

SHA is part of the in-crypto extensions on Power8 and Power9.

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-mcpu=power8`; while IBM XL C/C++ compilers require `-qarch=pwr8 -qaltivec`. Also see PowerPC's `__CRYPTO` preprocessor macro.

Note
  This function is only available on PowerPC and PowerPC-64 platforms

Definition at line 695 of file cpu.h.

## ◆ HasDARN()

bool HasDARN | ( |  | ) |
| inline

Determine if a PowerPC processor has DARN available.

Returns
  true if the hardware is capable of DARN at runtime, false otherwise.

Runtime support requires compile time support. When compiling with GCC, you may need to compile with `-mcpu=power9`; while IBM XL C/C++ compilers require `-qarch=pwr9 -qaltivec`. Also see PowerPC's `_ALTIVEC_` preprocessor macro.

Note
  This function is only available on PowerPC and PowerPC-64 platforms

Definition at line 722 of file cpu.h.