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Retire run-time detection of hardware POPCNT

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It was meant to build a single binary optimized
for any kind of CPU: with and without hardware POPCNT.

This is a nice idea but in practice was never used, or
people builds binary with popcnt enabled or not, mainly
according to their type of CPU. And it was also never
used in the official Jim's builds where, in case, would
be easier for a number of reasons, do build two different
versions: with and without SEE42 support.

So retire this feature and simplify the code.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This commit is contained in:
Marco Costalba
2011-12-30 11:30:26 +01:00
parent 20a6f99cdb
commit 0a6532a39d
6 changed files with 56 additions and 74 deletions
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24
src/types.h
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@@ -124,30 +124,22 @@ inline void __cpuid(int CPUInfo[4], int)
#define FORCE_INLINE inline
#endif
/// cpu_has_popcnt() detects support for popcnt instruction at runtime
inline bool cpu_has_popcnt() {
int CPUInfo[4] = {-1};
__cpuid(CPUInfo, 0x00000001);
return (CPUInfo[2] >> 23) & 1;
}
/// CpuHasPOPCNT is a global constant initialized at startup that
/// is set to true if CPU on which application runs supports popcnt
/// hardware instruction. Unless USE_POPCNT is not defined.
/// HasPopCnt is a global constant initialized at compile time that is set to
/// true if CPU on which application runs supports popcnt hardware instruction.
#if defined(USE_POPCNT)
const bool CpuHasPOPCNT = cpu_has_popcnt();
const bool HasPopCnt = true;
#else
const bool CpuHasPOPCNT = false;
const bool HasPopCnt = false;
#endif
/// CpuIs64Bit is a global constant initialized at compile time that
/// is set to true if CPU on which application runs is a 64 bits.
/// Is64Bit is a global constant initialized at compile time that is set to
/// true if CPU on which application runs is a 64 bits.
#if defined(IS_64BIT)
const bool CpuIs64Bit = true;
const bool Is64Bit = true;
#else
const bool CpuIs64Bit = false;
const bool Is64Bit = false;
#endif
#include <string>