src/hotspot/cpu/x86/abstractInterpreter_x86.cpp

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#include "ci/ciMethod.hpp"
#include "interpreter/interpreter.hpp"
#include "oops/klass.inline.hpp"
#include "runtime/frame.inline.hpp"


// asm based interpreter deoptimization helpers
int AbstractInterpreter::size_activation(int max_stack,
                                         int temps,
                                         int extra_args,
                                         int monitors,
                                         int callee_params,
                                         int callee_locals,
                                         bool is_top_frame) {
  // Note: This calculation must exactly parallel the frame setup
  // in TemplateInterpreterGenerator::generate_fixed_frame.

  // fixed size of an interpreter frame:
  int overhead = frame::sender_sp_offset -
                 frame::interpreter_frame_initial_sp_offset;
  // Our locals were accounted for by the caller (or last_frame_adjust
  // on the transition) Since the callee parameters already account
  // for the callee's params we only need to account for the extra
  // locals.
  int size = overhead +
         (callee_locals - callee_params)*Interpreter::stackElementWords +
         monitors * frame::interpreter_frame_monitor_size() +
         temps* Interpreter::stackElementWords + extra_args;

  return size;
}

void AbstractInterpreter::layout_activation(Method* method,
                                            int tempcount,
                                            int popframe_extra_args,
                                            int moncount,
                                            int caller_actual_parameters,
                                            int callee_param_count,
                                            int callee_locals,
                                            frame* caller,
                                            frame* interpreter_frame,
                                            bool is_top_frame,
                                            bool is_bottom_frame) {
  // The frame interpreter_frame is guaranteed to be the right size,
  // as determined by a previous call to the size_activation() method.
  // It is also guaranteed to be walkable even though it is in a
  // skeletal state

  int max_locals = method->max_locals() * Interpreter::stackElementWords;
  int extra_locals = (method->max_locals() - method->size_of_parameters()) *
    Interpreter::stackElementWords;

#ifdef ASSERT
  assert(caller->sp() == interpreter_frame->sender_sp(), "Frame not properly walkable");
#endif

  interpreter_frame->interpreter_frame_set_method(method);
  // NOTE the difference in using sender_sp and
  // interpreter_frame_sender_sp interpreter_frame_sender_sp is
  // the original sp of the caller (the unextended_sp) and
  // sender_sp is fp+8/16 (32bit/64bit) XXX
  intptr_t* locals = interpreter_frame->sender_sp() + max_locals - 1;

#ifdef ASSERT
  if (caller->is_interpreted_frame()) {
    // Test exact placement on top of caller args
    intptr_t* l2 = caller->interpreter_frame_last_sp() + caller_actual_parameters - 1;
    assert(l2 <= caller->interpreter_frame_expression_stack(), "bad placement");
    assert(l2 >= locals, "bad placement");
  }
#endif

  interpreter_frame->interpreter_frame_set_locals(locals);
  BasicObjectLock* montop = interpreter_frame->interpreter_frame_monitor_begin();
  BasicObjectLock* monbot = montop - moncount;
  interpreter_frame->interpreter_frame_set_monitor_end(monbot);

  // Set last_sp
  intptr_t*  esp = (intptr_t*) monbot -
    tempcount*Interpreter::stackElementWords -
    popframe_extra_args;
  interpreter_frame->interpreter_frame_set_last_sp(esp);

  // All frames but the initial (oldest) interpreter frame we fill in have
  // a value for sender_sp that allows walking the stack but isn't
  // truly correct. Correct the value here.
  if (extra_locals != 0 &&
      interpreter_frame->sender_sp() ==
      interpreter_frame->interpreter_frame_sender_sp()) {
    interpreter_frame->set_interpreter_frame_sender_sp(caller->sp() +
                                                       extra_locals);
  }
  *interpreter_frame->interpreter_frame_cache_addr() =
    method->constants()->cache();
  *interpreter_frame->interpreter_frame_mirror_addr() =
    method->method_holder()->java_mirror();
}

#ifndef _LP64
int AbstractInterpreter::BasicType_as_index(BasicType type) {
  int i = 0;
  switch (type) {
    case T_BOOLEAN: i = 0; break;
    case T_CHAR   : i = 1; break;
    case T_BYTE   : i = 2; break;
    case T_SHORT  : i = 3; break;
    case T_INT    : // fall through
    case T_LONG   : // fall through
    case T_VOID   : i = 4; break;
    case T_FLOAT  : i = 5; break;  // have to treat float and double separately for SSE
    case T_DOUBLE : i = 6; break;
    case T_OBJECT : // fall through
    case T_ARRAY  : i = 7; break;
    default       : ShouldNotReachHere();
  }
  assert(0 <= i && i < AbstractInterpreter::number_of_result_handlers, "index out of bounds");
  return i;
}
#else
int AbstractInterpreter::BasicType_as_index(BasicType type) {
  int i = 0;
  switch (type) {
    case T_BOOLEAN: i = 0; break;
    case T_CHAR   : i = 1; break;
    case T_BYTE   : i = 2; break;
    case T_SHORT  : i = 3; break;
    case T_INT    : i = 4; break;
    case T_LONG   : i = 5; break;
    case T_VOID   : i = 6; break;
    case T_FLOAT  : i = 7; break;
    case T_DOUBLE : i = 8; break;
    case T_OBJECT : i = 9; break;
    case T_ARRAY  : i = 9; break;
    default       : ShouldNotReachHere();
  }
  assert(0 <= i && i < AbstractInterpreter::number_of_result_handlers,
         "index out of bounds");
  return i;
}
#endif // _LP64

// How much stack a method activation needs in words.
int AbstractInterpreter::size_top_interpreter_activation(Method* method) {
  const int entry_size = frame::interpreter_frame_monitor_size();

  // total overhead size: entry_size + (saved rbp thru expr stack
  // bottom).  be sure to change this if you add/subtract anything
  // to/from the overhead area
  const int overhead_size =
    -(frame::interpreter_frame_initial_sp_offset) + entry_size;

#ifndef _LP64
  const int stub_code = 4;  // see generate_call_stub
#else
  const int stub_code = frame::entry_frame_after_call_words;
#endif

  const int method_stack = (method->max_locals() + method->max_stack()) *
                           Interpreter::stackElementWords;
  return (overhead_size + method_stack + stub_code);
}