src/hotspot/os_cpu/solaris_sparc/count_trailing_zeros_solaris_sparc.hpp
author phh
Sat, 30 Nov 2019 14:33:05 -0800
changeset 59330 5b96c12f909d
parent 53244 9807daeb47c4
permissions -rw-r--r--
8234541: C1 emits an empty message when it inlines successfully Summary: Use "inline" as the message when successfull Reviewed-by: thartmann, mdoerr Contributed-by: navy.xliu@gmail.com

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#ifndef OS_CPU_SOLARIS_SPARC_COUNT_TRAILING_ZEROS_SOLARIS_SPARC_HPP
#define OS_CPU_SOLARIS_SPARC_COUNT_TRAILING_ZEROS_SOLARIS_SPARC_HPP

#include "utilities/globalDefinitions.hpp"

inline unsigned count_trailing_zeros(uintx x) {
  assert(x != 0, "precondition");
  // Reduce to mask with ones in all positions below the least
  // significant set bit of x, and zeros otherwise.
  uintx rx = (x - 1) & ~x;      // sub x, 1, rx; andn rx, x, rx;
  // Then count the set bits in the reduction.
  uintx result;
  __asm__(" popc %1, %0\n\t" : "=r" (result) : "r" (rx));
  return result;
}

#endif // OS_CPU_SOLARIS_SPARC_COUNT_TRAILING_ZEROS_SOLARIS_SPARC_HPP