src/share/vm/c1/c1_LIR.hpp

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>

@@ -918,10 +918,11 @@
       , lir_membar_loadload
       , lir_membar_storestore
       , lir_membar_loadstore
       , lir_membar_storeload
       , lir_get_thread
+      , lir_on_spin_wait
   , end_op0
   , begin_op1
       , lir_fxch
       , lir_fld
       , lir_ffree

@@ -2099,10 +2100,12 @@
   void build_frame()                             { append(new LIR_Op0(lir_build_frame)); }
 
   void std_entry(LIR_Opr receiver)               { append(new LIR_Op0(lir_std_entry, receiver)); }
   void osr_entry(LIR_Opr osrPointer)             { append(new LIR_Op0(lir_osr_entry, osrPointer)); }
 
+  void on_spin_wait()                            { append(new LIR_Op0(lir_on_spin_wait)); }
+
   void branch_destination(Label* lbl)            { append(new LIR_OpLabel(lbl)); }
 
   void negate(LIR_Opr from, LIR_Opr to)          { append(new LIR_Op1(lir_neg, from, to)); }
   void leal(LIR_Opr from, LIR_Opr result_reg)    { append(new LIR_Op1(lir_leal, from, result_reg)); }