src/cpu/x86/vm/frame_x86.cpp

rev 7386 : 8068945: Use RBP register as proper frame pointer in JIT compiled code on x86
Summary: Introduce the PreserveFramePointer flag to control if RBP is used as the frame pointer or as a general purpose register.
Reviewed-by: kvn, roland, dlong, enevill, shade

*** 214,224 ****
      }
  
      if (sender_blob->is_nmethod()) {
          nmethod* nm = sender_blob->as_nmethod_or_null();
          if (nm != NULL) {
!             if (nm->is_deopt_mh_entry(sender_pc) || nm->is_deopt_entry(sender_pc)) {
                  return false;
              }
          }
      }
  
--- 214,225 ----
      }
  
      if (sender_blob->is_nmethod()) {
          nmethod* nm = sender_blob->as_nmethod_or_null();
          if (nm != NULL) {
!             if (nm->is_deopt_mh_entry(sender_pc) || nm->is_deopt_entry(sender_pc) ||
!                 nm->method()->is_method_handle_intrinsic()) {
                  return false;
              }
          }
      }
  
*** 381,430 ****
  
  //------------------------------------------------------------------------------
  // frame::verify_deopt_original_pc
  //
  // Verifies the calculated original PC of a deoptimization PC for the
! // given unextended SP.  The unextended SP might also be the saved SP
! // for MethodHandle call sites.
  #ifdef ASSERT
! void frame::verify_deopt_original_pc(nmethod* nm, intptr_t* unextended_sp, bool is_method_handle_return) {
    frame fr;
  
    // This is ugly but it's better than to change {get,set}_original_pc
    // to take an SP value as argument.  And it's only a debugging
    // method anyway.
    fr._unextended_sp = unextended_sp;
  
    address original_pc = nm->get_original_pc(&fr);
    assert(nm->insts_contains(original_pc), "original PC must be in nmethod");
-   assert(nm->is_method_handle_return(original_pc) == is_method_handle_return, "must be");
  }
  #endif
  
  //------------------------------------------------------------------------------
  // frame::adjust_unextended_sp
  void frame::adjust_unextended_sp() {
!   // If we are returning to a compiled MethodHandle call site, the
!   // saved_fp will in fact be a saved value of the unextended SP.  The
!   // simplest way to tell whether we are returning to such a call site
!   // is as follows:
  
    nmethod* sender_nm = (_cb == NULL) ? NULL : _cb->as_nmethod_or_null();
    if (sender_nm != NULL) {
!     // If the sender PC is a deoptimization point, get the original
!     // PC.  For MethodHandle call site the unextended_sp is stored in
!     // saved_fp.
!     if (sender_nm->is_deopt_mh_entry(_pc)) {
!       DEBUG_ONLY(verify_deopt_mh_original_pc(sender_nm, _fp));
!       _unextended_sp = _fp;
!     }
!     else if (sender_nm->is_deopt_entry(_pc)) {
        DEBUG_ONLY(verify_deopt_original_pc(sender_nm, _unextended_sp));
      }
-     else if (sender_nm->is_method_handle_return(_pc)) {
-       _unextended_sp = _fp;
-     }
    }
  }
  
  //------------------------------------------------------------------------------
  // frame::update_map_with_saved_link
--- 382,420 ----
  
  //------------------------------------------------------------------------------
  // frame::verify_deopt_original_pc
  //
  // Verifies the calculated original PC of a deoptimization PC for the
! // given unextended SP.
  #ifdef ASSERT
! void frame::verify_deopt_original_pc(nmethod* nm, intptr_t* unextended_sp) {
    frame fr;
  
    // This is ugly but it's better than to change {get,set}_original_pc
    // to take an SP value as argument.  And it's only a debugging
    // method anyway.
    fr._unextended_sp = unextended_sp;
  
    address original_pc = nm->get_original_pc(&fr);
    assert(nm->insts_contains(original_pc), "original PC must be in nmethod");
  }
  #endif
  
  //------------------------------------------------------------------------------
  // frame::adjust_unextended_sp
  void frame::adjust_unextended_sp() {
!   // On x86, sites calling method handle intrinsics and lambda forms are treated
!   // as any other call site. Therefore, no special action is needed when we are
!   // returning to any of these call sites.
  
    nmethod* sender_nm = (_cb == NULL) ? NULL : _cb->as_nmethod_or_null();
    if (sender_nm != NULL) {
!     // If the sender PC is a deoptimization point, get the original PC.
!     if (sender_nm->is_deopt_entry(_pc) ||
!         sender_nm->is_deopt_mh_entry(_pc)) {
        DEBUG_ONLY(verify_deopt_original_pc(sender_nm, _unextended_sp));
      }
    }
  }
  
  //------------------------------------------------------------------------------
  // frame::update_map_with_saved_link