8353192: C2: Clean up x86 backend after 32-bit x86 removal

Reviewed-by: kvn, epeter

Author: shipilev

src/hotspot/cpu/x86/c2_CodeStubs_x86.cpp

@@ -43,22 +43,8 @@ void C2SafepointPollStub::emit(C2_MacroAssembler& masm) {
 
   __ bind(entry());
   InternalAddress safepoint_pc(masm.pc() - masm.offset() + _safepoint_offset);
-#ifdef _LP64
   __ lea(rscratch1, safepoint_pc);
   __ movptr(Address(r15_thread, JavaThread::saved_exception_pc_offset()), rscratch1);
-#else
-  const Register tmp1 = rcx;
-  const Register tmp2 = rdx;
-  __ push(tmp1);
-  __ push(tmp2);
-
-  __ lea(tmp1, safepoint_pc);
-  __ get_thread(tmp2);
-  __ movptr(Address(tmp2, JavaThread::saved_exception_pc_offset()), tmp1);
-
-  __ pop(tmp2);
-  __ pop(tmp1);
-#endif
   __ jump(callback_addr);
 }