src/share/vm/c1/c1_LIRGenerator.cpp

rev 10271 : 8147844: new method j.l.Runtime.onSpinWait() and the corresponding x86 hotspot instrinsic
Summary: adds c1 & c2 x86 intrinsics for j.l.Runtime.onSpinWait() that utilize the PAUSE instruction
Reviewed-by: iveresov, kvn, vlivanov
Contributed-by: Ivan Krylov <ivan@azul.com>, Yuri Gaevsky <ygaevsky@azul.com>

*** 3166,3176 ****
      if (os::is_MP()) __ membar_release();
      break;
    case vmIntrinsics::_fullFence :
      if (os::is_MP()) __ membar();
      break;
! 
    case vmIntrinsics::_Reference_get:
      do_Reference_get(x);
      break;
  
    case vmIntrinsics::_updateCRC32:
--- 3166,3178 ----
      if (os::is_MP()) __ membar_release();
      break;
    case vmIntrinsics::_fullFence :
      if (os::is_MP()) __ membar();
      break;
!   case vmIntrinsics::_onSpinWait:
!     __ on_spin_wait();
!     break;
    case vmIntrinsics::_Reference_get:
      do_Reference_get(x);
      break;
  
    case vmIntrinsics::_updateCRC32: