src/share/vm/c1/c1_Compiler.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>

*** 129,138 ****
--- 129,141 ----
      if (UseCompressedOops && !VM_Version::supports_atomic_getset4()) return false;
  #else
      if (!VM_Version::supports_atomic_getset4()) return false;
  #endif
      break;
+   case vmIntrinsics::_onSpinWait:
+     if (!VM_Version::supports_on_spin_wait()) return false;
+     break;
    case vmIntrinsics::_arraycopy:
    case vmIntrinsics::_currentTimeMillis:
    case vmIntrinsics::_nanoTime:
    case vmIntrinsics::_Reference_get:
      // Use the intrinsic version of Reference.get() so that the value in