folly::compression::instructions::Nehalem Struct Reference

#include <Instructions.h>

Inheritance diagram for folly::compression::instructions::Nehalem:

Static Public Member Functions
static bool	supported (const folly::CpuId &cpuId={})
static FOLLY_ALWAYS_INLINE uint64_t	popcount (uint64_t value)
Static Public Member Functions inherited from folly::compression::instructions::Default
static bool	supported (const folly::CpuId &={})
static FOLLY_ALWAYS_INLINE uint64_t	popcount (uint64_t value)
static FOLLY_ALWAYS_INLINE int	ctz (uint64_t value)
static FOLLY_ALWAYS_INLINE int	clz (uint64_t value)
static FOLLY_ALWAYS_INLINE uint64_t	blsr (uint64_t value)
static FOLLY_ALWAYS_INLINE uint64_t	bextr (uint64_t value, uint32_t start, uint32_t length)
static FOLLY_ALWAYS_INLINE uint64_t	bzhi (uint64_t value, uint32_t index)

Detailed Description

Definition at line 86 of file Instructions.h.

Member Function Documentation

static FOLLY_ALWAYS_INLINE uint64_t folly::compression::instructions::Nehalem::popcount ( uint64_t  value )

inlinestatic

Definition at line 91 of file Instructions.h.

References uint64_t.

                                                               {
// POPCNT is supported starting with Intel Nehalem, AMD K10.
#if defined(__GNUC__) || defined(__clang__)
    // GCC and Clang won't inline the intrinsics.
    uint64_t result;
    asm("popcntq %1, %0" : "=r"(result) : "r"(value));
    return result;
#else
    return uint64_t(_mm_popcnt_u64(value));
#endif
  }

static bool folly::compression::instructions::Nehalem::supported ( const folly::CpuId &  cpuId = {} )

inlinestatic

Definition at line 87 of file Instructions.h.

Referenced by folly::compression::instructions::detect(), and folly::compression::instructions::Haswell::supported().

                                                  {}) {
    return cpuId.popcnt();
  }

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The documentation for this struct was generated from the following file:

• proxygen/folly/folly/experimental/Instructions.h