/*

 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "interpreter/interpreter.hpp"

#include "interpreter/interpreterGenerator.hpp"

#include "oops/constMethod.hpp"

#include "oops/method.hpp"

#include "runtime/arguments.hpp"

#include "runtime/frame.inline.hpp"

#include "runtime/synchronizer.hpp"

#include "utilities/macros.hpp"

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;

}

bool AbstractInterpreter::can_be_compiled(methodHandle m) {

  // No special entry points that preclude compilation

  return true;

}

static int size_activation_helper(int callee_extra_locals, int max_stack, int monitor_size) {

  // Figure out the size of an interpreter frame (in words) given that we have a fully allocated

  // expression stack, the callee will have callee_extra_locals (so we can account for

  // frame extension) and monitor_size for monitors. Basically we need to calculate

  // this exactly like generate_fixed_frame/generate_compute_interpreter_state.

  //

  //

  // The big complicating thing here is that we must ensure that the stack stays properly

  // aligned. This would be even uglier if monitor size wasn't modulo what the stack

  // needs to be aligned for). We are given that the sp (fp) is already aligned by

  // the caller so we must ensure that it is properly aligned for our callee.

  //

  const int rounded_vm_local_words =

       round_to(frame::interpreter_frame_vm_local_words,WordsPerLong);

  // callee_locals and max_stack are counts, not the size in frame.

  const int locals_size =

       round_to(callee_extra_locals * Interpreter::stackElementWords, WordsPerLong);

  const int max_stack_words = max_stack * Interpreter::stackElementWords;

  return (round_to((max_stack_words

                   + rounded_vm_local_words

                   + frame::memory_parameter_word_sp_offset), WordsPerLong)

                   // already rounded

                   + locals_size + monitor_size);

}

// How much stack a method top interpreter activation needs in words.

int AbstractInterpreter::size_top_interpreter_activation(Method* method) {

  // See call_stub code

  int call_stub_size  = round_to(7 + frame::memory_parameter_word_sp_offset,

                                 WordsPerLong);    // 7 + register save area

  // Save space for one monitor to get into the interpreted method in case

  // the method is synchronized

  int monitor_size    = method->is_synchronized() ?

                                1*frame::interpreter_frame_monitor_size() : 0;

  return size_activation_helper(method->max_locals(), method->max_stack(),

                                monitor_size) + call_stub_size;

}

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 InterpreterGenerator::generate_fixed_frame.

  int monitor_size           = monitors * frame::interpreter_frame_monitor_size();

  assert(monitor_size == round_to(monitor_size, WordsPerLong), "must align");

  //

  // Note: if you look closely this appears to be doing something much different

  // than generate_fixed_frame. What is happening is this. On sparc we have to do

  // this dance with interpreter_sp_adjustment because the window save area would

  // appear just below the bottom (tos) of the caller's java expression stack. Because

  // the interpreter want to have the locals completely contiguous generate_fixed_frame

  // will adjust the caller's sp for the "extra locals" (max_locals - parameter_size).

  // Now in generate_fixed_frame the extension of the caller's sp happens in the callee.

  // In this code the opposite occurs the caller adjusts it's own stack base on the callee.

  // This is mostly ok but it does cause a problem when we get to the initial frame (the oldest)

  // because the oldest frame would have adjust its callers frame and yet that frame

  // already exists and isn't part of this array of frames we are unpacking. So at first

  // glance this would seem to mess up that frame. However Deoptimization::fetch_unroll_info_helper()

  // will after it calculates all of the frame's on_stack_size()'s will then figure out the

  // amount to adjust the caller of the initial (oldest) frame and the calculation will all

  // add up. It does seem like it simpler to account for the adjustment here (and remove the

  // callee... parameters here). However this would mean that this routine would have to take

  // the caller frame as input so we could adjust its sp (and set it's interpreter_sp_adjustment)

  // and run the calling loop in the reverse order. This would also would appear to mean making

  // this code aware of what the interactions are when that initial caller fram was an osr or

  // other adapter frame. deoptimization is complicated enough and  hard enough to debug that

  // there is no sense in messing working code.

  //

  int rounded_cls = round_to((callee_locals - callee_params), WordsPerLong);

  assert(rounded_cls == round_to(rounded_cls, WordsPerLong), "must align");

  int raw_frame_size = size_activation_helper(rounded_cls, max_stack, monitor_size);

  return raw_frame_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_local_count,

                                            frame* caller,

                                            frame* interpreter_frame,

                                            bool is_top_frame,

                                            bool is_bottom_frame) {

  // Set up the following variables:

  //   - Lmethod

  //   - Llocals

  //   - Lmonitors (to the indicated number of monitors)

  //   - Lesp (to the indicated number of temps)

  // The frame caller on entry is a description of the caller of the

  // frame we are about to layout. We are guaranteed that we will be

  // able to fill in a new interpreter frame as its callee (i.e. the

  // stack space is allocated and the amount was determined by an

  // earlier call to the size_activation() method).  On return caller

  // while describe the interpreter frame we just layed out.

  // The skeleton frame must already look like an interpreter frame

  // even if not fully filled out.

  assert(interpreter_frame->is_interpreted_frame(), "Must be interpreted frame");

  int rounded_vm_local_words = round_to(frame::interpreter_frame_vm_local_words,WordsPerLong);

  int monitor_size           = moncount * frame::interpreter_frame_monitor_size();

  assert(monitor_size == round_to(monitor_size, WordsPerLong), "must align");

  intptr_t* fp = interpreter_frame->fp();

  JavaThread* thread = JavaThread::current();

  RegisterMap map(thread, false);

  // More verification that skeleton frame is properly walkable

  assert(fp == caller->sp(), "fp must match");

  intptr_t* montop     = fp - rounded_vm_local_words;

  // preallocate monitors (cf. __ add_monitor_to_stack)

  intptr_t* monitors = montop - monitor_size;

  // preallocate stack space

  intptr_t*  esp = monitors - 1 -

    (tempcount * Interpreter::stackElementWords) -

    popframe_extra_args;

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

  NEEDS_CLEANUP;

  intptr_t* locals;

  if (caller->is_interpreted_frame()) {

    // Can force the locals area to end up properly overlapping the top of the expression stack.

    intptr_t* Lesp_ptr = caller->interpreter_frame_tos_address() - 1;

    // Note that this computation means we replace size_of_parameters() values from the caller

    // interpreter frame's expression stack with our argument locals

    int parm_words  = caller_actual_parameters * Interpreter::stackElementWords;

    locals = Lesp_ptr + parm_words;

    int delta = local_words - parm_words;

    int computed_sp_adjustment = (delta > 0) ? round_to(delta, WordsPerLong) : 0;

    *interpreter_frame->register_addr(I5_savedSP)    = (intptr_t) (fp + computed_sp_adjustment) - STACK_BIAS;

    if (!is_bottom_frame) {

      // Llast_SP is set below for the current frame to SP (with the

      // extra space for the callee's locals). Here we adjust

      // Llast_SP for the caller's frame, removing the extra space

      // for the current method's locals.

      *caller->register_addr(Llast_SP) = *interpreter_frame->register_addr(I5_savedSP);

    } else {

      assert(*caller->register_addr(Llast_SP) >= *interpreter_frame->register_addr(I5_savedSP), "strange Llast_SP");

    }

  } else {

    assert(caller->is_compiled_frame() || caller->is_entry_frame(), "only possible cases");

    // Don't have Lesp available; lay out locals block in the caller

    // adjacent to the register window save area.

    //

    // Compiled frames do not allocate a varargs area which is why this if

    // statement is needed.

    //

    if (caller->is_compiled_frame()) {

      locals = fp + frame::register_save_words + local_words - 1;

    } else {

      locals = fp + frame::memory_parameter_word_sp_offset + local_words - 1;

    }

    if (!caller->is_entry_frame()) {

      // Caller wants his own SP back

      int caller_frame_size = caller->cb()->frame_size();

      *interpreter_frame->register_addr(I5_savedSP) = (intptr_t)(caller->fp() - caller_frame_size) - STACK_BIAS;

    }

  }

  if (TraceDeoptimization) {

    if (caller->is_entry_frame()) {

      // make sure I5_savedSP and the entry frames notion of saved SP

      // agree.  This assertion duplicate a check in entry frame code

      // but catches the failure earlier.

      assert(*caller->register_addr(Lscratch) == *interpreter_frame->register_addr(I5_savedSP),

             "would change callers SP");

    }

    if (caller->is_entry_frame()) {

      tty->print("entry ");

    }

    if (caller->is_compiled_frame()) {

      tty->print("compiled ");

      if (caller->is_deoptimized_frame()) {

        tty->print("(deopt) ");

      }

    }

    if (caller->is_interpreted_frame()) {

      tty->print("interpreted ");

    }

    tty->print_cr("caller fp=" INTPTR_FORMAT " sp=" INTPTR_FORMAT, p2i(caller->fp()), p2i(caller->sp()));

    tty->print_cr("save area = " INTPTR_FORMAT ", " INTPTR_FORMAT, p2i(caller->sp()), p2i(caller->sp() + 16));

    tty->print_cr("save area = " INTPTR_FORMAT ", " INTPTR_FORMAT, p2i(caller->fp()), p2i(caller->fp() + 16));

    tty->print_cr("interpreter fp=" INTPTR_FORMAT ", " INTPTR_FORMAT, p2i(interpreter_frame->fp()), p2i(interpreter_frame->sp()));

    tty->print_cr("save area = " INTPTR_FORMAT ", " INTPTR_FORMAT, p2i(interpreter_frame->sp()), p2i(interpreter_frame->sp() + 16));

    tty->print_cr("save area = " INTPTR_FORMAT ", " INTPTR_FORMAT, p2i(interpreter_frame->fp()), p2i(interpreter_frame->fp() + 16));

    tty->print_cr("Llocals = " INTPTR_FORMAT, p2i(locals));

    tty->print_cr("Lesp = " INTPTR_FORMAT, p2i(esp));

    tty->print_cr("Lmonitors = " INTPTR_FORMAT, p2i(monitors));

  }

  if (method->max_locals() > 0) {

    assert(locals < caller->sp() || locals >= (caller->sp() + 16), "locals in save area");

    assert(locals < caller->fp() || locals > (caller->fp() + 16), "locals in save area");

    assert(locals < interpreter_frame->sp() || locals > (interpreter_frame->sp() + 16), "locals in save area");

    assert(locals < interpreter_frame->fp() || locals >= (interpreter_frame->fp() + 16), "locals in save area");

  }

#ifdef _LP64

  assert(*interpreter_frame->register_addr(I5_savedSP) & 1, "must be odd");

#endif

  *interpreter_frame->register_addr(Lmethod)     = (intptr_t) method;

  *interpreter_frame->register_addr(Llocals)     = (intptr_t) locals;

  *interpreter_frame->register_addr(Lmonitors)   = (intptr_t) monitors;

  *interpreter_frame->register_addr(Lesp)        = (intptr_t) esp;

  // Llast_SP will be same as SP as there is no adapter space

  *interpreter_frame->register_addr(Llast_SP)    = (intptr_t) interpreter_frame->sp() - STACK_BIAS;

  *interpreter_frame->register_addr(LcpoolCache) = (intptr_t) method->constants()->cache();

#ifdef FAST_DISPATCH

  *interpreter_frame->register_addr(IdispatchTables) = (intptr_t) Interpreter::dispatch_table();

#endif

#ifdef ASSERT

  BasicObjectLock* mp = (BasicObjectLock*)monitors;

  assert(interpreter_frame->interpreter_frame_method() == method, "method matches");

  assert(interpreter_frame->interpreter_frame_local_at(9) == (intptr_t *)((intptr_t)locals - (9 * Interpreter::stackElementSize)), "locals match");

  assert(interpreter_frame->interpreter_frame_monitor_end()   == mp, "monitor_end matches");

  assert(((intptr_t *)interpreter_frame->interpreter_frame_monitor_begin()) == ((intptr_t *)mp)+monitor_size, "monitor_begin matches");

  assert(interpreter_frame->interpreter_frame_tos_address()-1 == esp, "esp matches");

  // check bounds

  intptr_t* lo = interpreter_frame->sp() + (frame::memory_parameter_word_sp_offset - 1);

  intptr_t* hi = interpreter_frame->fp() - rounded_vm_local_words;

  assert(lo < monitors && montop <= hi, "monitors in bounds");

  assert(lo <= esp && esp < monitors, "esp in bounds");

#endif // ASSERT

}