/*

 * Copyright (c) 1997, 2019, 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 "memory/allocation.hpp"

#include "memory/allocation.inline.hpp"

#include "memory/arena.hpp"

#include "memory/metaspaceShared.hpp"

#include "memory/resourceArea.hpp"

#include "runtime/os.hpp"

#include "runtime/task.hpp"

#include "runtime/threadCritical.hpp"

#include "services/memTracker.hpp"

#include "utilities/ostream.hpp"

// allocate using malloc; will fail if no memory available

char* AllocateHeap(size_t size,

                   MEMFLAGS flags,

                   const NativeCallStack& stack,

                   AllocFailType alloc_failmode /* = AllocFailStrategy::EXIT_OOM*/) {

  char* p = (char*) os::malloc(size, flags, stack);

  if (p == NULL && alloc_failmode == AllocFailStrategy::EXIT_OOM) {

    vm_exit_out_of_memory(size, OOM_MALLOC_ERROR, "AllocateHeap");

  }

  return p;

}

char* AllocateHeap(size_t size,

                   MEMFLAGS flags,

                   AllocFailType alloc_failmode /* = AllocFailStrategy::EXIT_OOM*/) {

  return AllocateHeap(size, flags, CALLER_PC);

}

char* ReallocateHeap(char *old,

                     size_t size,

                     MEMFLAGS flag,

                     AllocFailType alloc_failmode) {

  char* p = (char*) os::realloc(old, size, flag, CALLER_PC);

  if (p == NULL && alloc_failmode == AllocFailStrategy::EXIT_OOM) {

    vm_exit_out_of_memory(size, OOM_MALLOC_ERROR, "ReallocateHeap");

  }

  return p;

}

// handles NULL pointers

void FreeHeap(void* p) {

  os::free(p);

}

void* MetaspaceObj::_shared_metaspace_base = NULL;

void* MetaspaceObj::_shared_metaspace_top  = NULL;

void* StackObj::operator new(size_t size)     throw() { ShouldNotCallThis(); return 0; }

void  StackObj::operator delete(void* p)              { ShouldNotCallThis(); }

void* StackObj::operator new [](size_t size)  throw() { ShouldNotCallThis(); return 0; }

void  StackObj::operator delete [](void* p)           { ShouldNotCallThis(); }

void* MetaspaceObj::operator new(size_t size, ClassLoaderData* loader_data,

                                 size_t word_size,

                                 MetaspaceObj::Type type, TRAPS) throw() {

  // Klass has it's own operator new

  return Metaspace::allocate(loader_data, word_size, type, THREAD);

}

bool MetaspaceObj::is_valid(const MetaspaceObj* p) {

  // Weed out obvious bogus values first without traversing metaspace

  if ((size_t)p < os::min_page_size()) {

    return false;

  } else if (!is_aligned((address)p, sizeof(MetaWord))) {

    return false;

  }

  return Metaspace::contains((void*)p);

}

void MetaspaceObj::print_address_on(outputStream* st) const {

  st->print(" {" INTPTR_FORMAT "}", p2i(this));

}

void* ResourceObj::operator new(size_t size, Arena *arena) throw() {

  address res = (address)arena->Amalloc(size);

  DEBUG_ONLY(set_allocation_type(res, ARENA);)

  return res;

}

void* ResourceObj::operator new [](size_t size, Arena *arena) throw() {

  address res = (address)arena->Amalloc(size);

  DEBUG_ONLY(set_allocation_type(res, ARENA);)

  return res;

}

void* ResourceObj::operator new(size_t size, allocation_type type, MEMFLAGS flags) throw() {

  address res = NULL;

  switch (type) {

   case C_HEAP:

    res = (address)AllocateHeap(size, flags, CALLER_PC);

    DEBUG_ONLY(set_allocation_type(res, C_HEAP);)

    break;

   case RESOURCE_AREA:

    // new(size) sets allocation type RESOURCE_AREA.

    res = (address)operator new(size);

    break;

   default:

    ShouldNotReachHere();

  }

  return res;

}

void* ResourceObj::operator new [](size_t size, allocation_type type, MEMFLAGS flags) throw() {

  return (address) operator new(size, type, flags);

}

void* ResourceObj::operator new(size_t size, const std::nothrow_t&  nothrow_constant,

    allocation_type type, MEMFLAGS flags) throw() {

  // should only call this with std::nothrow, use other operator new() otherwise

  address res = NULL;

  switch (type) {

   case C_HEAP:

    res = (address)AllocateHeap(size, flags, CALLER_PC, AllocFailStrategy::RETURN_NULL);

    DEBUG_ONLY(if (res!= NULL) set_allocation_type(res, C_HEAP);)

    break;

   case RESOURCE_AREA:

    // new(size) sets allocation type RESOURCE_AREA.

    res = (address)operator new(size, std::nothrow);

    break;

   default:

    ShouldNotReachHere();

  }

  return res;

}

void* ResourceObj::operator new [](size_t size, const std::nothrow_t&  nothrow_constant,

    allocation_type type, MEMFLAGS flags) throw() {

  return (address)operator new(size, nothrow_constant, type, flags);

}

void ResourceObj::operator delete(void* p) {

  assert(((ResourceObj *)p)->allocated_on_C_heap(),

         "delete only allowed for C_HEAP objects");

  DEBUG_ONLY(((ResourceObj *)p)->_allocation_t[0] = (uintptr_t)badHeapOopVal;)

  FreeHeap(p);

}

void ResourceObj::operator delete [](void* p) {

  operator delete(p);

}

#ifdef ASSERT

void ResourceObj::set_allocation_type(address res, allocation_type type) {

  // Set allocation type in the resource object

  uintptr_t allocation = (uintptr_t)res;

  assert((allocation & allocation_mask) == 0, "address should be aligned to 4 bytes at least: " INTPTR_FORMAT, p2i(res));

  assert(type <= allocation_mask, "incorrect allocation type");

  ResourceObj* resobj = (ResourceObj *)res;

  resobj->_allocation_t[0] = ~(allocation + type);

  if (type != STACK_OR_EMBEDDED) {

    // Called from operator new(), set verification value.

    resobj->_allocation_t[1] = (uintptr_t)&(resobj->_allocation_t[1]) + type;

  }

}

ResourceObj::allocation_type ResourceObj::get_allocation_type() const {

  assert(~(_allocation_t[0] | allocation_mask) == (uintptr_t)this, "lost resource object");

  return (allocation_type)((~_allocation_t[0]) & allocation_mask);

}

bool ResourceObj::is_type_set() const {

  allocation_type type = (allocation_type)(_allocation_t[1] & allocation_mask);

  return get_allocation_type()  == type &&

         (_allocation_t[1] - type) == (uintptr_t)(&_allocation_t[1]);

}

// This whole business of passing information from ResourceObj::operator new

// to the ResourceObj constructor via fields in the "object" is technically UB.

// But it seems to work within the limitations of HotSpot usage (such as no

// multiple inheritance) with the compilers and compiler options we're using.

// And it gives some possibly useful checking for misuse of ResourceObj.

void ResourceObj::initialize_allocation_info() {

  if (~(_allocation_t[0] | allocation_mask) != (uintptr_t)this) {

    // Operator new() is not called for allocations

    // on stack and for embedded objects.

    set_allocation_type((address)this, STACK_OR_EMBEDDED);

  } else if (allocated_on_stack()) { // STACK_OR_EMBEDDED

    // For some reason we got a value which resembles

    // an embedded or stack object (operator new() does not

    // set such type). Keep it since it is valid value

    // (even if it was garbage).

    // Ignore garbage in other fields.

  } else if (is_type_set()) {

    // Operator new() was called and type was set.

    assert(!allocated_on_stack(),

           "not embedded or stack, this(" PTR_FORMAT ") type %d a[0]=(" PTR_FORMAT ") a[1]=(" PTR_FORMAT ")",

           p2i(this), get_allocation_type(), _allocation_t[0], _allocation_t[1]);

  } else {

    // Operator new() was not called.

    // Assume that it is embedded or stack object.

    set_allocation_type((address)this, STACK_OR_EMBEDDED);

  }

  _allocation_t[1] = 0; // Zap verification value

}

ResourceObj::ResourceObj() {

  initialize_allocation_info();

}

ResourceObj::ResourceObj(const ResourceObj&) {

  // Initialize _allocation_t as a new object, ignoring object being copied.

  initialize_allocation_info();

}

ResourceObj& ResourceObj::operator=(const ResourceObj& r) {

  assert(allocated_on_stack(),

         "copy only into local, this(" PTR_FORMAT ") type %d a[0]=(" PTR_FORMAT ") a[1]=(" PTR_FORMAT ")",

         p2i(this), get_allocation_type(), _allocation_t[0], _allocation_t[1]);

  // Keep current _allocation_t value;

  return *this;

}

ResourceObj::~ResourceObj() {

  // allocated_on_C_heap() also checks that encoded (in _allocation) address == this.

  if (!allocated_on_C_heap()) { // ResourceObj::delete() will zap _allocation for C_heap.

    _allocation_t[0] = (uintptr_t)badHeapOopVal; // zap type

  }

}

#endif // ASSERT

//--------------------------------------------------------------------------------------

// Non-product code

#ifndef PRODUCT

void AllocatedObj::print() const       { print_on(tty); }

void AllocatedObj::print_value() const { print_value_on(tty); }

void AllocatedObj::print_on(outputStream* st) const {

  st->print_cr("AllocatedObj(" INTPTR_FORMAT ")", p2i(this));

}

void AllocatedObj::print_value_on(outputStream* st) const {

  st->print("AllocatedObj(" INTPTR_FORMAT ")", p2i(this));

}

ReallocMark::ReallocMark() {

#ifdef ASSERT

  Thread *thread = Thread::current();

  _nesting = thread->resource_area()->nesting();

#endif

}

void ReallocMark::check() {

#ifdef ASSERT

  if (_nesting != Thread::current()->resource_area()->nesting()) {

    fatal("allocation bug: array could grow within nested ResourceMark");

  }

#endif

}

#endif // Non-product