/*

 * 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 "code/codeCache.hpp"

#include "interpreter/interpreter.hpp"

#include "memory/resourceArea.hpp"

#include "oops/markOop.hpp"

#include "oops/method.hpp"

#include "oops/oop.inline.hpp"

#include "prims/methodHandles.hpp"

#include "runtime/frame.inline.hpp"

#include "runtime/handles.inline.hpp"

#include "runtime/javaCalls.hpp"

#include "runtime/monitorChunk.hpp"

#include "runtime/signature.hpp"

#include "runtime/stubCodeGenerator.hpp"

#include "runtime/stubRoutines.hpp"

#include "vmreg_sparc.inline.hpp"

#ifdef COMPILER1

#include "c1/c1_Runtime1.hpp"

#include "runtime/vframeArray.hpp"

#endif

void RegisterMap::pd_clear() {

  if (_thread->has_last_Java_frame()) {

    frame fr = _thread->last_frame();

    _window = fr.sp();

  } else {

    _window = NULL;

  }

  _younger_window = NULL;

}

// Unified register numbering scheme: each 32-bits counts as a register

// number, so all the V9 registers take 2 slots.

const static int R_L_nums[] = {0+040,2+040,4+040,6+040,8+040,10+040,12+040,14+040};

const static int R_I_nums[] = {0+060,2+060,4+060,6+060,8+060,10+060,12+060,14+060};

const static int R_O_nums[] = {0+020,2+020,4+020,6+020,8+020,10+020,12+020,14+020};

const static int R_G_nums[] = {0+000,2+000,4+000,6+000,8+000,10+000,12+000,14+000};

static RegisterMap::LocationValidType bad_mask = 0;

static RegisterMap::LocationValidType R_LIO_mask = 0;

static bool register_map_inited = false;

static void register_map_init() {

  if (!register_map_inited) {

    register_map_inited = true;

    int i;

    for (i = 0; i < 8; i++) {

      assert(R_L_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");

      assert(R_I_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");

      assert(R_O_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");

      assert(R_G_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");

    }

    bad_mask |= (1LL << R_O_nums[6]); // SP

    bad_mask |= (1LL << R_O_nums[7]); // cPC

    bad_mask |= (1LL << R_I_nums[6]); // FP

    bad_mask |= (1LL << R_I_nums[7]); // rPC

    bad_mask |= (1LL << R_G_nums[2]); // TLS

    bad_mask |= (1LL << R_G_nums[7]); // reserved by libthread

    for (i = 0; i < 8; i++) {

      R_LIO_mask |= (1LL << R_L_nums[i]);

      R_LIO_mask |= (1LL << R_I_nums[i]);

      R_LIO_mask |= (1LL << R_O_nums[i]);

    }

  }

}

address RegisterMap::pd_location(VMReg regname) const {

  register_map_init();

  assert(regname->is_reg(), "sanity check");

  // Only the GPRs get handled this way

  if( !regname->is_Register())

    return NULL;

  // don't talk about bad registers

  if ((bad_mask & ((LocationValidType)1 << regname->value())) != 0) {

    return NULL;

  }

  // Convert to a GPR

  Register reg;

  int second_word = 0;

  // 32-bit registers for in, out and local

  if (!regname->is_concrete()) {

    // HMM ought to return NULL for any non-concrete (odd) vmreg

    // this all tied up in the fact we put out double oopMaps for

    // register locations. When that is fixed we'd will return NULL

    // (or assert here).

    reg = regname->prev()->as_Register();

#ifdef _LP64

    second_word = sizeof(jint);

#else

    return NULL;

#endif // _LP64

  } else {

    reg = regname->as_Register();

  }

  if (reg->is_out()) {

    assert(_younger_window != NULL, "Younger window should be available");

    return second_word + (address)&_younger_window[reg->after_save()->sp_offset_in_saved_window()];

  }

  if (reg->is_local() || reg->is_in()) {

    assert(_window != NULL, "Window should be available");

    return second_word + (address)&_window[reg->sp_offset_in_saved_window()];

  }

  // Only the window'd GPRs get handled this way; not the globals.

  return NULL;

}

#ifdef ASSERT

void RegisterMap::check_location_valid() {

  register_map_init();

  assert((_location_valid[0] & bad_mask) == 0, "cannot have special locations for SP,FP,TLS,etc.");

}

#endif

// We are shifting windows.  That means we are moving all %i to %o,

// getting rid of all current %l, and keeping all %g.  This is only

// complicated if any of the location pointers for these are valid.

// The normal case is that everything is in its standard register window

// home, and _location_valid[0] is zero.  In that case, this routine

// does exactly nothing.

void RegisterMap::shift_individual_registers() {

  if (!update_map())  return;  // this only applies to maps with locations

  register_map_init();

  check_location_valid();

  LocationValidType lv = _location_valid[0];

  LocationValidType lv0 = lv;

  lv &= ~R_LIO_mask;  // clear %l, %o, %i regs

  // if we cleared some non-%g locations, we may have to do some shifting

  if (lv != lv0) {

    // copy %i0-%i5 to %o0-%o5, if they have special locations

    // This can happen in within stubs which spill argument registers

    // around a dynamic link operation, such as resolve_opt_virtual_call.

    for (int i = 0; i < 8; i++) {

      if (lv0 & (1LL << R_I_nums[i])) {

        _location[R_O_nums[i]] = _location[R_I_nums[i]];

        lv |=  (1LL << R_O_nums[i]);

      }

    }

  }

  _location_valid[0] = lv;

  check_location_valid();

}

bool frame::safe_for_sender(JavaThread *thread) {

  address _SP = (address) sp();

  address _FP = (address) fp();

  address _UNEXTENDED_SP = (address) unextended_sp();

  // sp must be within the stack

  bool sp_safe = (_SP <= thread->stack_base()) &&

                 (_SP >= thread->stack_base() - thread->stack_size());

  if (!sp_safe) {

    return false;

  }

  // unextended sp must be within the stack and above or equal sp

  bool unextended_sp_safe = (_UNEXTENDED_SP <= thread->stack_base()) &&

                            (_UNEXTENDED_SP >= _SP);

  if (!unextended_sp_safe) return false;

  // an fp must be within the stack and above (but not equal) sp

  bool fp_safe = (_FP <= thread->stack_base()) &&

                 (_FP > _SP);

  // We know sp/unextended_sp are safe only fp is questionable here

  // If the current frame is known to the code cache then we can attempt to

  // to construct the sender and do some validation of it. This goes a long way

  // toward eliminating issues when we get in frame construction code

  if (_cb != NULL ) {

    // First check if frame is complete and tester is reliable

    // Unfortunately we can only check frame complete for runtime stubs and nmethod

    // other generic buffer blobs are more problematic so we just assume they are

    // ok. adapter blobs never have a frame complete and are never ok.

    if (!_cb->is_frame_complete_at(_pc)) {

      if (_cb->is_nmethod() || _cb->is_adapter_blob() || _cb->is_runtime_stub()) {

        return false;

      }

    }

    // Could just be some random pointer within the codeBlob

    if (!_cb->code_contains(_pc)) {

      return false;

    }

    // Entry frame checks

    if (is_entry_frame()) {

      // an entry frame must have a valid fp.

      if (!fp_safe) {

        return false;

      }

      // Validate the JavaCallWrapper an entry frame must have

      address jcw = (address)entry_frame_call_wrapper();

      bool jcw_safe = (jcw <= thread->stack_base()) && ( jcw > _FP);

      return jcw_safe;

    }

    intptr_t* younger_sp = sp();

    intptr_t* _SENDER_SP = sender_sp(); // sender is actually just _FP

    bool adjusted_stack = is_interpreted_frame();

    address   sender_pc = (address)younger_sp[I7->sp_offset_in_saved_window()] + pc_return_offset;

    // We must always be able to find a recognizable pc

    CodeBlob* sender_blob = CodeCache::find_blob_unsafe(sender_pc);

    if (sender_pc == NULL ||  sender_blob == NULL) {

      return false;

    }

    // Could be a zombie method

    if (sender_blob->is_zombie() || sender_blob->is_unloaded()) {

      return false;

    }

    // It should be safe to construct the sender though it might not be valid

    frame sender(_SENDER_SP, younger_sp, adjusted_stack);

    // Do we have a valid fp?

    address sender_fp = (address) sender.fp();

    // an fp must be within the stack and above (but not equal) current frame's _FP

    bool sender_fp_safe = (sender_fp <= thread->stack_base()) &&

                   (sender_fp > _FP);

    if (!sender_fp_safe) {

      return false;

    }

    // If the potential sender is the interpreter then we can do some more checking

    if (Interpreter::contains(sender_pc)) {

      return sender.is_interpreted_frame_valid(thread);

    }

    // Could just be some random pointer within the codeBlob

    if (!sender.cb()->code_contains(sender_pc)) {

      return false;

    }

    // We should never be able to see an adapter if the current frame is something from code cache

    if (sender_blob->is_adapter_blob()) {

      return false;

    }

    if( sender.is_entry_frame()) {

      // Validate the JavaCallWrapper an entry frame must have

      address jcw = (address)sender.entry_frame_call_wrapper();

      bool jcw_safe = (jcw <= thread->stack_base()) && ( jcw > sender_fp);

      return jcw_safe;

    }

    // If the frame size is 0 something (or less) is bad because every nmethod has a non-zero frame size

    // because you must allocate window space

    if (sender_blob->frame_size() <= 0) {

      assert(!sender_blob->is_nmethod(), "should count return address at least");

      return false;

    }

    // The sender should positively be an nmethod or call_stub. On sparc we might in fact see something else.

    // The cause of this is because at a save instruction the O7 we get is a leftover from an earlier

    // window use. So if a runtime stub creates two frames (common in fastdebug/debug) then we see the

    // stale pc. So if the sender blob is not something we'd expect we have little choice but to declare

    // the stack unwalkable. pd_get_top_frame_for_signal_handler tries to recover from this by unwinding

    // that initial frame and retrying.

    if (!sender_blob->is_nmethod()) {

      return false;

    }

    // Could put some more validation for the potential non-interpreted sender

    // frame we'd create by calling sender if I could think of any. Wait for next crash in forte...

    // One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb

    // We've validated the potential sender that would be created

    return true;

  }

  // Must be native-compiled frame. Since sender will try and use fp to find

  // linkages it must be safe

  if (!fp_safe) return false;

  // could try and do some more potential verification of native frame if we could think of some...

  return true;

}

// constructors

// Construct an unpatchable, deficient frame

void frame::init(intptr_t* sp, address pc, CodeBlob* cb) {

#ifdef _LP64

  assert( (((intptr_t)sp & (wordSize-1)) == 0), "frame constructor passed an invalid sp");

#endif

  _sp = sp;

  _younger_sp = NULL;

  _pc = pc;

  _cb = cb;

  _sp_adjustment_by_callee = 0;

  assert(pc == NULL && cb == NULL || pc != NULL, "can't have a cb and no pc!");

  if (_cb == NULL && _pc != NULL ) {

    _cb = CodeCache::find_blob(_pc);

  }

  _deopt_state = unknown;

#ifdef ASSERT

  if ( _cb != NULL && _cb->is_nmethod()) {

    // Without a valid unextended_sp() we can't convert the pc to "original"

    assert(!((nmethod*)_cb)->is_deopt_pc(_pc), "invariant broken");

  }

#endif // ASSERT

}

frame::frame(intptr_t* sp, unpatchable_t, address pc, CodeBlob* cb) {

  init(sp, pc, cb);

}

frame::frame(intptr_t* sp, intptr_t* younger_sp, bool younger_frame_is_interpreted) :

  _sp(sp),

  _younger_sp(younger_sp),

  _deopt_state(unknown),

  _sp_adjustment_by_callee(0) {

  if (younger_sp == NULL) {

    // make a deficient frame which doesn't know where its PC is

    _pc = NULL;

    _cb = NULL;

  } else {

    _pc = (address)younger_sp[I7->sp_offset_in_saved_window()] + pc_return_offset;

    assert( (intptr_t*)younger_sp[FP->sp_offset_in_saved_window()] == (intptr_t*)((intptr_t)sp - STACK_BIAS), "younger_sp must be valid");

    // Any frame we ever build should always "safe" therefore we should not have to call

    // find_blob_unsafe

    // In case of native stubs, the pc retrieved here might be

    // wrong.  (the _last_native_pc will have the right value)

    // So do not put add any asserts on the _pc here.

  }

  if (_pc != NULL)

    _cb = CodeCache::find_blob(_pc);

  // Check for MethodHandle call sites.

  if (_cb != NULL) {

    nmethod* nm = _cb->as_nmethod_or_null();

    if (nm != NULL) {

      if (nm->is_deopt_mh_entry(_pc) || nm->is_method_handle_return(_pc)) {

        _sp_adjustment_by_callee = (intptr_t*) ((intptr_t) sp[L7_mh_SP_save->sp_offset_in_saved_window()] + STACK_BIAS) - sp;

        // The SP is already adjusted by this MH call site, don't

        // overwrite this value with the wrong interpreter value.

        younger_frame_is_interpreted = false;

      }

    }

  }

  if (younger_frame_is_interpreted) {

    // compute adjustment to this frame's SP made by its interpreted callee

    _sp_adjustment_by_callee = (intptr_t*) ((intptr_t) younger_sp[I5_savedSP->sp_offset_in_saved_window()] + STACK_BIAS) - sp;

  }

  // It is important that the frame is fully constructed when we do

  // this lookup as get_deopt_original_pc() needs a correct value for

  // unextended_sp() which uses _sp_adjustment_by_callee.

  if (_pc != NULL) {

    address original_pc = nmethod::get_deopt_original_pc(this);

    if (original_pc != NULL) {

      _pc = original_pc;

      _deopt_state = is_deoptimized;

    } else {

      _deopt_state = not_deoptimized;

    }

  }

}

#ifndef PRODUCT

// This is a generic constructor which is only used by pns() in debug.cpp.

frame::frame(void* sp, void* fp, void* pc) {

  init((intptr_t*)sp, (address)pc, NULL);

}

#endif

bool frame::is_interpreted_frame() const  {

  return Interpreter::contains(pc());

}

// sender_sp

intptr_t* frame::interpreter_frame_sender_sp() const {

  assert(is_interpreted_frame(), "interpreted frame expected");

  return fp();

}

void frame::set_interpreter_frame_sender_sp(intptr_t* sender_sp) {

  assert(is_interpreted_frame(), "interpreted frame expected");

  Unimplemented();

}

frame frame::sender_for_entry_frame(RegisterMap *map) const {

  assert(map != NULL, "map must be set");

  // Java frame called from C; skip all C frames and return top C

  // frame of that chunk as the sender

  JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();

  assert(!entry_frame_is_first(), "next Java fp must be non zero");

  assert(jfa->last_Java_sp() > _sp, "must be above this frame on stack");

  intptr_t* last_Java_sp = jfa->last_Java_sp();

  // Since we are walking the stack now this nested anchor is obviously walkable

  // even if it wasn't when it was stacked.

  if (!jfa->walkable()) {

    // Capture _last_Java_pc (if needed) and mark anchor walkable.

    jfa->capture_last_Java_pc(_sp);

  }

  assert(jfa->last_Java_pc() != NULL, "No captured pc!");

  map->clear();

  map->make_integer_regs_unsaved();

  map->shift_window(last_Java_sp, NULL);

  assert(map->include_argument_oops(), "should be set by clear");

  return frame(last_Java_sp, frame::unpatchable, jfa->last_Java_pc());

}

frame frame::sender_for_interpreter_frame(RegisterMap *map) const {

  ShouldNotCallThis();

  return sender(map);

}

frame frame::sender_for_compiled_frame(RegisterMap *map) const {

  ShouldNotCallThis();

  return sender(map);

}

frame frame::sender(RegisterMap* map) const {

  assert(map != NULL, "map must be set");

  assert(CodeCache::find_blob_unsafe(_pc) == _cb, "inconsistent");

  // Default is not to follow arguments; update it accordingly below

  map->set_include_argument_oops(false);

  if (is_entry_frame()) return sender_for_entry_frame(map);

  intptr_t* younger_sp = sp();

  intptr_t* sp         = sender_sp();

  // Note:  The version of this operation on any platform with callee-save

  //        registers must update the register map (if not null).

  //        In order to do this correctly, the various subtypes of

  //        of frame (interpreted, compiled, glue, native),

  //        must be distinguished.  There is no need on SPARC for

  //        such distinctions, because all callee-save registers are

  //        preserved for all frames via SPARC-specific mechanisms.

  //

  //        *** HOWEVER, *** if and when we make any floating-point

  //        registers callee-saved, then we will have to copy over

  //        the RegisterMap update logic from the Intel code.

  // The constructor of the sender must know whether this frame is interpreted so it can set the

  // sender's _sp_adjustment_by_callee field.  An osr adapter frame was originally

  // interpreted but its pc is in the code cache (for c1 -> osr_frame_return_id stub), so it must be

  // explicitly recognized.