src/cpu/x86/vm/frame_x86.hpp

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

*** 74,96 ****
  //    [struct interpretState   ] <-----------------------------------------|
  //    [return pc               ] (return to callee of frame manager [1]
  //    [locals and parameters   ]
  //                               <- sender sp
  
! // [1] When the c++ interpreter calls a new method it returns to the frame
  //     manager which allocates a new frame on the stack. In that case there
  //     is no real callee of this newly allocated frame. The frame manager is
  //     aware of the  additional frame(s) and will pop them as nested calls
! //     complete. Howevers tTo make it look good in the debugger the frame
  //     manager actually installs a dummy pc pointing to RecursiveInterpreterActivation
  //     with a fake interpreter_state* parameter to make it easy to debug
  //     nested calls.
  
  // Note that contrary to the layout for the assembly interpreter the
  // expression stack allocated for the C++ interpreter is full sized.
  // However this is not as bad as it seems as the interpreter frame_manager
! // will truncate the unused space on succesive method calls.
  //
  // ------------------------------ C++ interpreter ----------------------------------------
  
   public:
    enum {
--- 74,96 ----
  //    [struct interpretState   ] <-----------------------------------------|
  //    [return pc               ] (return to callee of frame manager [1]
  //    [locals and parameters   ]
  //                               <- sender sp
  
! // [1] When the C++ interpreter calls a new method it returns to the frame
  //     manager which allocates a new frame on the stack. In that case there
  //     is no real callee of this newly allocated frame. The frame manager is
  //     aware of the additional frame(s) and will pop them as nested calls
! //     complete. However, to make it look good in the debugger the frame
  //     manager actually installs a dummy pc pointing to RecursiveInterpreterActivation
  //     with a fake interpreter_state* parameter to make it easy to debug
  //     nested calls.
  
  // Note that contrary to the layout for the assembly interpreter the
  // expression stack allocated for the C++ interpreter is full sized.
  // However this is not as bad as it seems as the interpreter frame_manager
! // will truncate the unused space on successive method calls.
  //
  // ------------------------------ C++ interpreter ----------------------------------------
  
   public:
    enum {
*** 170,183 ****
      return (intptr_t*) addr_at(offset);
    }
  
  #ifdef ASSERT
    // Used in frame::sender_for_{interpreter,compiled}_frame
!   static void verify_deopt_original_pc(   nmethod* nm, intptr_t* unextended_sp, bool is_method_handle_return = false);
!   static void verify_deopt_mh_original_pc(nmethod* nm, intptr_t* unextended_sp) {
!     verify_deopt_original_pc(nm, unextended_sp, true);
!   }
  #endif
  
   public:
    // Constructors
  
--- 170,180 ----
      return (intptr_t*) addr_at(offset);
    }
  
  #ifdef ASSERT
    // Used in frame::sender_for_{interpreter,compiled}_frame
!   static void verify_deopt_original_pc(nmethod* nm, intptr_t* unextended_sp);
  #endif
  
   public:
    // Constructors