824 lines
No EOL
22 KiB
C++
824 lines
No EOL
22 KiB
C++
#include <iostream>
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#include <stdexcept>
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#include <stdlib.h>
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#include <vector>
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#include <unordered_map>
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#include <chrono>
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#include <queue>
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#include <set>
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#include "heap.hpp"
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#define time_now std::chrono::high_resolution_clock::now()
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#define to_us std::chrono::duration_cast<std::chrono::microseconds>
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using std::cout, std::endl, std::vector, std::hex, std::dec, std::unordered_map;
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namespace GC
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{
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/**
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* This implementation of the() guarantees laziness
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* on the instance and a correct destruction with
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* the destructor.
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*
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* @returns The singleton object.
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*/
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Heap& Heap::the()
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{
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static Heap instance;
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return instance;
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}
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/**
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* Initialises the heap singleton and saves the address
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* of the calling function's stack frame as the stack_top.
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* Presumeably this address points to the stack frame of
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* the compiled LLVM executable after linking.
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*/
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void Heap::init()
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{
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Heap &heap = Heap::the();
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if (heap.profiler_enabled())
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Profiler::record(HeapInit);
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// clang complains because arg for __b_f_a is not 0 which is "unsafe"
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#pragma clang diagnostic ignored "-Wframe-address"
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heap.m_stack_top = static_cast<uintptr_t *>(__builtin_frame_address(1));
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// TODO: handle this below
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//heap.m_heap_top = heap.m_heap;
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}
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void Heap::set_profiler_log_options(RecordOption flags)
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{
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Profiler::set_log_options(flags);
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}
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/**
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* Disposes the heap and the profiler at program exit
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* which also triggers a heap log file dumped if the
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* profiler is enabled.
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*/
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void Heap::dispose()
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{
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Heap &heap = Heap::the();
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if (heap.profiler_enabled())
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Profiler::dispose();
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}
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/**
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* Allocates a given amount of bytes on the heap.
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*
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* @param size The amount of bytes to be allocated.
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*
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* @return A pointer to the address where the memory
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* has been allocated. This pointer is supposed
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* to be casted to and object pointer.
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*/
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void *Heap::alloc(size_t size)
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{
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auto a_start = time_now;
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// Singleton
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Heap &heap = Heap::the();
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bool profiler_enabled = heap.profiler_enabled();
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if (profiler_enabled)
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Profiler::record(AllocStart, size);
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if (size == 0)
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{
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cout << "Heap: Cannot alloc 0B. No bytes allocated." << endl;
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return nullptr;
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}
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if (heap.m_size + size > HEAP_SIZE)
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{
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// auto a_ms = to_us(c_start - a_start);
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// Profiler::record(AllocStart, a_ms);
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auto stack_bottom = reinterpret_cast<uintptr_t *>(__builtin_frame_address(0));
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heap.collect(stack_bottom);
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// If memory is not enough after collect, crash with OOM error
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if (heap.m_size > HEAP_SIZE)
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{
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throw std::runtime_error(std::string("Error: Heap out of memory"));
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}
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//throw std::runtime_error(std::string("Error: Heap out of memory"));
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}
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if (heap.m_size + size > HEAP_SIZE)
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{
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if (profiler_enabled)
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Profiler::dispose();
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throw std::runtime_error(std::string("Error: Heap out of memory"));
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}
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// If a chunk was recycled, return the old chunk address
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Chunk *reused_chunk = heap.try_recycle_chunks(size);
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if (reused_chunk != nullptr)
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{
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if (profiler_enabled)
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Profiler::record(ReusedChunk, reused_chunk);
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auto a_end = time_now;
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auto a_ms = to_us(a_end - a_start);
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Profiler::record(AllocStart, a_ms);
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return static_cast<void *>(reused_chunk->m_start);
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}
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// If no free chunks was found (reused_chunk is a nullptr),
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// then create a new chunk
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auto new_chunk = new Chunk(size, (uintptr_t *)(heap.m_heap + heap.m_size));
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heap.m_size += size;
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// TODO: handle this below
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//heap.m_total_size += size;
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heap.m_allocated_chunks.push_back(new_chunk);
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if (profiler_enabled)
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Profiler::record(NewChunk, new_chunk);
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auto a_end = time_now;
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auto a_ms = to_us(a_end - a_start);
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Profiler::record(AllocStart, a_ms);
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return new_chunk->m_start;
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}
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/**
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* Tries to recycle used and freed chunks that are
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* already allocated objects by the OS but freed
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* from our Heap. This reduces the amount of GC
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* objects slightly which saves time from malloc'ing
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* memory from the OS.
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*
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* @param size Amount of bytes needed for the object
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* which is about to be allocated.
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*
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* @returns If a chunk is found and recycled, a
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* pointer to the allocated memory for
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* the object is returned. If not, a
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* nullptr is returned to signify no
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* chunks were found.
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*/
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Chunk *Heap::try_recycle_chunks(size_t size)
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{
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Heap &heap = Heap::the();
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// Check if there are any freed chunks large enough for current request
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for (size_t i = 0; i < heap.m_freed_chunks.size(); i++)
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{
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//auto chunk = Heap::get_at(heap.m_freed_chunks, i);
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auto chunk = heap.m_freed_chunks[i];
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auto iter = heap.m_freed_chunks.begin();
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i++;
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//advance(iter, i);
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if (chunk->m_size > size)
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{
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// Split the chunk, use one part and add the remaining part to
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// the list of freed chunks
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size_t diff = chunk->m_size - size;
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auto chunk_complement = new Chunk(diff, chunk->m_start + chunk->m_size);
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heap.m_freed_chunks.erase(iter);
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heap.m_freed_chunks.push_back(chunk_complement);
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heap.m_allocated_chunks.push_back(chunk);
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return chunk;
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}
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else if (chunk->m_size == size)
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{
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// Reuse the whole chunk
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heap.m_freed_chunks.erase(iter);
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heap.m_allocated_chunks.push_back(chunk);
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return chunk;
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}
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}
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// If no chunk was found, return nullptr
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return nullptr;
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}
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/**
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* Returns a bool whether the profiler is enabled
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* or not.
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*
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* @returns True or false if the profiler is enabled
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* or disabled respectively.
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*/
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bool Heap::profiler_enabled() {
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Heap &heap = Heap::the();
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return heap.m_profiler_enable;
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}
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/**
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* Collection phase of the garbage collector. When
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* an allocation is requested and there is no space
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* left on the heap, a collection is triggered. This
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* function is private so that the user cannot trigger
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* a collection unneccessarily.
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*/
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void Heap::collect(uintptr_t *stack_bottom)
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{
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auto c_start = time_now;
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Heap &heap = Heap::the();
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if (heap.profiler_enabled())
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Profiler::record(CollectStart);
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// get current stack frame
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stack_bottom = reinterpret_cast<uintptr_t *>(__builtin_frame_address(0));
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if (heap.m_stack_top == nullptr)
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throw std::runtime_error(std::string("Error: Heap is not initialized, read the docs!"));
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// uintptr_t *stack_top = heap.m_stack_top;
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//auto work_list = heap.m_allocated_chunks;
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//mark(stack_bottom, stack_top, work_list);
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// Testing mark_hash, previous woking implementation above
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// create_table();
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// mark_hash(stack_bottom, stack_top);
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create_table();
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vector<uintptr_t *> roots;
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// cout << "\nb4 find_roots\n";
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find_roots(stack_bottom, roots);
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// cout << "b4 mark\n";''
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mark(roots);
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// cout << "b4 sweep\n";
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sweep(heap);
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// cout << "b4 free\n";
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free(heap);
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auto c_end = time_now;
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Profiler::record(CollectStart, to_us(c_end - c_start));
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}
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void Heap::find_roots(uintptr_t *stack_bottom, vector<uintptr_t *> &roots)
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{
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auto heap_bottom = reinterpret_cast<const uintptr_t>(m_heap);
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auto heap_top = reinterpret_cast<const uintptr_t>(m_heap + HEAP_SIZE);
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while (stack_bottom < m_stack_top)
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{
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if (heap_bottom < *stack_bottom && *stack_bottom < heap_top)
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{
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roots.push_back(stack_bottom);
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}
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stack_bottom++;
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}
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}
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void Heap::mark(vector<uintptr_t *> &roots)
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{
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bool prof_enabled = m_profiler_enable;
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if (prof_enabled)
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Profiler::record(MarkStart);
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auto iter = roots.begin(), end = roots.end();
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std::queue<std::pair<uintptr_t, uintptr_t>> chunk_spaces;
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while (iter != end)
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{
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find_chunks(*iter++, chunk_spaces);
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}
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while (!chunk_spaces.empty())
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{
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auto range = chunk_spaces.front();
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chunk_spaces.pop();
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auto addr_bottom = reinterpret_cast<uintptr_t *>(range.first);
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auto addr_top = reinterpret_cast<uintptr_t *>(range.second);
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while (addr_bottom < addr_top)
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{
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find_chunks(addr_bottom, chunk_spaces);
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addr_bottom++;
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}
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}
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}
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void Heap::find_chunks(uintptr_t *stack_addr, std::queue<std::pair<uintptr_t, uintptr_t>> &chunk_spaces)
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{
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Heap &heap = Heap::the();
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auto it = heap.m_chunk_table.find(*stack_addr);
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if (it != heap.m_chunk_table.end())
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{
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auto chunk = it->second;
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if (!chunk->m_marked)
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{
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auto c_start = reinterpret_cast<uintptr_t>(chunk->m_start);
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auto c_size = reinterpret_cast<uintptr_t>(chunk->m_size);
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auto c_end = reinterpret_cast<uintptr_t>(c_start + c_size);
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chunk->m_marked = true;
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chunk_spaces.push(std::make_pair(c_start, c_end));
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}
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}
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/* auto iter = m_allocated_chunks.begin();
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auto end = m_allocated_chunks.end();
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while (iter != end)
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{
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auto chunk = *iter++;
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if (chunk->m_marked)
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continue;
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auto c_start = reinterpret_cast<uintptr_t>(chunk->m_start);
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auto c_size = reinterpret_cast<uintptr_t>(chunk->m_size);
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auto c_end = reinterpret_cast<uintptr_t>(c_start + c_size);
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if (c_start < *stack_addr && *stack_addr < c_end)
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{
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chunk->m_marked = true;
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chunk_spaces.push(std::make_pair(c_start, c_end));
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}
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} */
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}
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void Heap::create_table()
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{
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Heap &heap = Heap::the();
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unordered_map<uintptr_t, Chunk*> chunk_table;
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for (auto chunk : heap.m_allocated_chunks) {
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auto pair = std::make_pair(reinterpret_cast<uintptr_t>(chunk->m_start), chunk);
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heap.m_chunk_table.insert(pair);
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}
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}
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void Heap::mark_hash(uintptr_t *start, const uintptr_t* const end)
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{
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Heap &heap = Heap::the();
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bool profiler_enabled = heap.m_profiler_enable;
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if (profiler_enabled)
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Profiler::record(MarkStart);
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for (; start <= end; start++)
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{
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auto search = heap.m_chunk_table.find(*start);
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if (search != heap.m_chunk_table.end())
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{
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Chunk *chunk = search->second;
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auto c_start = reinterpret_cast<uintptr_t>(chunk->m_start);
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auto c_size = reinterpret_cast<uintptr_t>(chunk->m_size);
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auto c_end = reinterpret_cast<uintptr_t*>(c_start + c_size);
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if (!chunk->m_marked)
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{
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chunk->m_marked = true;
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if (profiler_enabled)
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Profiler::record(ChunkMarked, chunk);
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//mark_hash(chunk->m_start, c_end);
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Chunk *next = find_pointer_hash((uintptr_t *) c_start, (uintptr_t *) c_end);
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while (next != NULL)
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{
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if (!next->m_marked)
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{
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next->m_marked = true;
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if (profiler_enabled)
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Profiler::record(ChunkMarked, chunk);
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auto c_start = reinterpret_cast<uintptr_t>(next->m_start);
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auto c_size = reinterpret_cast<uintptr_t>(next->m_size);
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auto c_end = reinterpret_cast<uintptr_t>(c_start + c_size);
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next = find_pointer_hash((uintptr_t *) c_start, (uintptr_t *) c_end);
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}
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}
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}
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}
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}
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}
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/**
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* Sweeps the heap, unmarks the marked chunks for the next cycle,
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* adds the unmarked nodes to the list of freed chunks; to be freed.
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*
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* Time complexity: O(N^2), where N is the number of allocated chunks.
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* It is quadratic, in the worst case,
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* since each call to erase() is linear.
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*
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* @param heap Pointer to the heap singleton instance.
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*/
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void Heap::sweep(Heap &heap)
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{
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bool profiler_enabled = heap.m_profiler_enable;
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if (profiler_enabled)
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Profiler::record(SweepStart);
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auto iter = heap.m_allocated_chunks.begin();
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// std::cout << "Chunks alloced: " << heap.m_allocated_chunks.size() << std::endl;
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// This cannot "iter != stop", results in seg fault, since the end gets updated, I think.
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while (iter != heap.m_allocated_chunks.end())
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{
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Chunk *chunk = *iter;
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// Unmark the marked chunks for the next iteration.
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if (chunk->m_marked)
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{
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chunk->m_marked = false;
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++iter;
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}
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else
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{
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// Add the unmarked chunks to freed chunks and remove from
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// the list of allocated chunks
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if (profiler_enabled)
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Profiler::record(ChunkSwept, chunk);
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heap.m_freed_chunks.push_back(chunk);
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iter = heap.m_allocated_chunks.erase(iter);
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heap.m_size -= chunk->m_size;
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// cout << "Decremented total heap size with: " << chunk->m_size << endl;
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// cout << "Total size is: " << heap.m_size << endl;
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}
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}
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// std::cout << "Chunks left: " << heap.m_allocated_chunks.size() << std::endl;
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}
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/**
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* Frees chunks that was moved to the list m_freed_chunks
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* by the sweep phase. If there are more than a certain
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* amount of free chunks, delete the free chunks to
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* avoid cluttering.
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*
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* Time complexity: O(N^2), where N is the freed chunks.
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* If free_overlap() is called, it runs in O(N^2),
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* otherwise O(N).
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*
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* @param heap Heap singleton instance, only for avoiding
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* redundant calls to the singleton get
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*/
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void Heap::free(Heap &heap)
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{
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bool profiler_enabled = heap.m_profiler_enable;
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if (profiler_enabled)
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Profiler::record(FreeStart);
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if (heap.m_freed_chunks.size() > FREE_THRESH)
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{
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bool profiler_enabled = heap.profiler_enabled();
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while (heap.m_freed_chunks.size())
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{
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auto chunk = heap.m_freed_chunks.back();
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heap.m_freed_chunks.pop_back();
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if (profiler_enabled)
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Profiler::record(ChunkFreed, chunk);
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// heap.m_size -= chunk->m_size;
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// cout << "Decremented total heap size with: " << chunk->m_size << endl;
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// cout << "Total size is: " << heap.m_size << endl;
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delete chunk;
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}
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}
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// if there are chunks but not more than FREE_THRESH
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else if (heap.m_freed_chunks.size())
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{
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// essentially, always check for overlap between
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// chunks before finishing the allocation
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free_overlap(heap);
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}
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}
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/**
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* Checks for overlaps between freed chunks of memory
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* and removes overlapping chunks while prioritizing
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* the chunks at lower addresses.
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*
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* Time complexity: O(N^2), where N is the number of freed chunks.
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* At each iteration get_at() is called, which is linear.
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*
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* @param heap Heap singleton instance, only for avoiding
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* redundant calls to the singleton get
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*
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* @note Maybe this should be changed to prioritizing
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* larger chunks. Should remove get_at() to indexing,
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* since that's constant.
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*/
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void Heap::free_overlap(Heap &heap) // borde göra en record(ChunkFreed) på onödiga chunks
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{
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std::vector<Chunk *> filtered;
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size_t i = 0;
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//auto prev = Heap::get_at(heap.m_freed_chunks, i++);
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auto prev = heap.m_freed_chunks[i++];
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prev->m_marked = true;
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filtered.push_back(prev);
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// cout << filtered.back()->m_start << endl;
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for (; i < heap.m_freed_chunks.size(); i++)
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{
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prev = filtered.back();
|
|
//auto next = Heap::get_at(heap.m_freed_chunks, i);
|
|
auto next = heap.m_freed_chunks[i];
|
|
auto p_start = (uintptr_t)(prev->m_start);
|
|
auto p_size = (uintptr_t)(prev->m_size);
|
|
auto n_start = (uintptr_t)(next->m_start);
|
|
if (n_start >= (p_start + p_size))
|
|
{
|
|
next->m_marked = true;
|
|
filtered.push_back(next);
|
|
}
|
|
}
|
|
heap.m_freed_chunks.swap(filtered);
|
|
|
|
bool profiler_enabled = heap.m_profiler_enable;
|
|
// After swap m_freed_chunks contains still available chunks
|
|
// and filtered contains all the chunks, so delete unused chunks
|
|
for (Chunk *chunk : filtered)
|
|
{
|
|
// if chunk was filtered away, delete it
|
|
if (!chunk->m_marked)
|
|
{
|
|
if (profiler_enabled)
|
|
Profiler::record(ChunkFreed, chunk);
|
|
heap.m_size -= chunk->m_size;
|
|
cout << "Decremented total heap size with: " << chunk->m_size << endl;
|
|
cout << "Total size is: " << heap.m_size << endl;
|
|
delete chunk;
|
|
}
|
|
else
|
|
{
|
|
chunk->m_marked = false;
|
|
}
|
|
}
|
|
}
|
|
|
|
void Heap::set_profiler(bool mode)
|
|
{
|
|
Heap &heap = Heap::the();
|
|
heap.m_profiler_enable = mode;
|
|
}
|
|
|
|
Chunk* find_pointer(uintptr_t *start, const uintptr_t* const end, vector<Chunk *> &worklist) {
|
|
for (; start <= end; start++) {
|
|
auto it = worklist.begin();
|
|
auto stop = worklist.end();
|
|
while (it != stop)
|
|
{
|
|
Chunk *chunk = *it;
|
|
auto c_start = reinterpret_cast<uintptr_t>(chunk->m_start);
|
|
auto c_size = reinterpret_cast<uintptr_t>(chunk->m_size);
|
|
auto c_end = reinterpret_cast<uintptr_t>(c_start + c_size);
|
|
|
|
// Check if the stack pointer points to something within the chunk
|
|
if (c_start <= *start && *start < c_end)
|
|
{
|
|
return chunk;
|
|
}
|
|
return NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Checks if a given chunk points to another chunk and returns it
|
|
Chunk* Heap::find_pointer_hash(uintptr_t *start, const uintptr_t* const end) {
|
|
Heap &heap = Heap::the();
|
|
for (; start <= end; start++) {
|
|
auto search = heap.m_chunk_table.find(*start);
|
|
if (search != heap.m_chunk_table.end()) {
|
|
return search->second;
|
|
}
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
#ifdef HEAP_DEBUG
|
|
/**
|
|
* Prints the result of Heap::init() and a dummy value
|
|
* for the current stack frame for reference.
|
|
*/
|
|
void Heap::check_init()
|
|
{
|
|
Heap &heap = Heap::the();
|
|
cout << "Heap addr:\t" << &heap << "\n";
|
|
cout << "GC m_stack_top:\t" << heap.m_stack_top << "\n";
|
|
auto stack_bottom = reinterpret_cast<uintptr_t *>(__builtin_frame_address(0));
|
|
cout << "GC stack_bottom:\t" << stack_bottom << endl;
|
|
}
|
|
|
|
/**
|
|
* Conditional collection, only to be used in debugging
|
|
*
|
|
* @param flags Bitmap of flags
|
|
*/
|
|
void Heap::collect(CollectOption flags)
|
|
{
|
|
set_profiler(true);
|
|
|
|
Heap &heap = Heap::the();
|
|
|
|
if (heap.m_profiler_enable)
|
|
Profiler::record(CollectStart);
|
|
|
|
cout << "DEBUG COLLECT\nFLAGS: ";
|
|
if (flags & MARK)
|
|
cout << "\n - MARK";
|
|
if (flags & SWEEP)
|
|
cout << "\n - SWEEP";
|
|
if (flags & FREE)
|
|
cout << "\n - FREE";
|
|
cout << "\n";
|
|
|
|
// get the frame adress, whwere local variables and saved registers are located
|
|
auto stack_bottom = reinterpret_cast<uintptr_t *>(__builtin_frame_address(0));
|
|
cout << "Stack bottom in collect:\t" << stack_bottom << "\n";
|
|
uintptr_t *stack_top = heap.m_stack_top;
|
|
|
|
cout << "Stack end in collect:\t " << stack_top << endl;
|
|
auto work_list = heap.m_allocated_chunks;
|
|
|
|
if (flags & MARK)
|
|
mark(stack_bottom, stack_top, work_list);
|
|
|
|
if (flags & SWEEP)
|
|
sweep(heap);
|
|
|
|
if (flags & FREE)
|
|
free(heap);
|
|
}
|
|
|
|
// Mark child references from the root references
|
|
void mark_test(vector<Chunk *> &worklist)
|
|
{
|
|
while (worklist.size() > 0)
|
|
{
|
|
Chunk *ref = worklist.back();
|
|
worklist.pop_back();
|
|
Chunk *child = (Chunk *)ref; // this is probably not correct
|
|
if (child != nullptr && !child->m_marked)
|
|
{
|
|
child->m_marked = true;
|
|
worklist.push_back(child);
|
|
mark_test(worklist);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Mark the root references and look for child references to them
|
|
void mark_from_roots(uintptr_t *start, const uintptr_t *end)
|
|
{
|
|
vector<Chunk *> worklist;
|
|
for (; start > end; start--)
|
|
{
|
|
if (*start % 8 == 0)
|
|
{ // all pointers must be aligned as double words
|
|
Chunk *ref = (Chunk *)*start;
|
|
if (ref != nullptr && !ref->m_marked)
|
|
{
|
|
ref->m_marked = true;
|
|
worklist.push_back(ref);
|
|
mark_test(worklist);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// For testing purposes
|
|
void Heap::print_line(Chunk *chunk)
|
|
{
|
|
cout << "Marked: " << chunk->m_marked << "\nStart adr: " << chunk->m_start << "\nSize: " << chunk->m_size << " B\n"
|
|
<< endl;
|
|
}
|
|
|
|
void Heap::print_worklist(std::vector<Chunk *> &list)
|
|
{
|
|
for (auto cp : list)
|
|
cout << "Chunk at:\t" << cp->m_start << "\nSize:\t\t" << cp->m_size << "\n";
|
|
cout << endl;
|
|
}
|
|
|
|
void Heap::print_contents()
|
|
{
|
|
Heap &heap = Heap::the();
|
|
if (heap.m_allocated_chunks.size())
|
|
{
|
|
cout << "\nALLOCATED CHUNKS #" << dec << heap.m_allocated_chunks.size() << endl;
|
|
for (auto chunk : heap.m_allocated_chunks)
|
|
print_line(chunk);
|
|
}
|
|
else
|
|
{
|
|
cout << "NO ALLOCATIONS\n" << endl;
|
|
}
|
|
if (heap.m_freed_chunks.size())
|
|
{
|
|
cout << "\nFREED CHUNKS #" << dec << heap.m_freed_chunks.size() << endl;
|
|
for (auto fchunk : heap.m_freed_chunks)
|
|
print_line(fchunk);
|
|
}
|
|
else
|
|
{
|
|
cout << "NO FREED CHUNKS" << endl;
|
|
}
|
|
}
|
|
|
|
void Heap::print_summary()
|
|
{
|
|
Heap &heap = Heap::the();
|
|
if (heap.m_allocated_chunks.size())
|
|
{
|
|
cout << "\nALLOCATED CHUNKS #" << dec << heap.m_allocated_chunks.size() << endl;
|
|
}
|
|
else
|
|
{
|
|
cout << "NO ALLOCATIONS\n" << endl;
|
|
}
|
|
if (heap.m_freed_chunks.size())
|
|
{
|
|
cout << "\nFREED CHUNKS #" << dec << heap.m_freed_chunks.size() << endl;
|
|
}
|
|
else
|
|
{
|
|
cout << "NO FREED CHUNKS" << endl;
|
|
}
|
|
}
|
|
|
|
void Heap::print_allocated_chunks(Heap *heap) {
|
|
cout << "--- Allocated Chunks ---\n" << endl;
|
|
for (auto chunk : heap->m_allocated_chunks) {
|
|
print_line(chunk);
|
|
}
|
|
}
|
|
|
|
Chunk *Heap::try_recycle_chunks_new(size_t size)
|
|
{
|
|
Heap &heap = Heap::the();
|
|
// Check if there are any freed chunks large enough for current request
|
|
for (size_t i = 0; i < heap.m_freed_chunks.size(); i++)
|
|
{
|
|
auto chunk = heap.m_freed_chunks[i]; //Heap::get_at(heap.m_freed_chunks, i);
|
|
auto iter = heap.m_freed_chunks.begin();
|
|
//advance(iter, i);
|
|
i++;
|
|
if (chunk->m_size > size)
|
|
{
|
|
// Split the chunk, use one part and add the remaining part to
|
|
// the list of freed chunks
|
|
size_t diff = chunk->m_size - size;
|
|
auto chunk_complement = new Chunk(diff, chunk->m_start + chunk->m_size);
|
|
|
|
heap.m_freed_chunks.erase(iter);
|
|
heap.m_freed_chunks.push_back(chunk_complement);
|
|
heap.m_allocated_chunks.push_back(chunk);
|
|
|
|
return chunk;
|
|
}
|
|
else if (chunk->m_size == size)
|
|
{
|
|
// Reuse the whole chunk
|
|
heap.m_freed_chunks.erase(iter);
|
|
heap.m_allocated_chunks.push_back(chunk);
|
|
return chunk;
|
|
}
|
|
}
|
|
// If no chunk was found, return nullptr
|
|
return nullptr;
|
|
}
|
|
|
|
void Heap::free_overlap_new(Heap &heap) // borde göra en record(ChunkFreed) på onödiga chunks
|
|
{
|
|
std::vector<Chunk *> filtered;
|
|
size_t i = 0;
|
|
auto prev = heap.m_freed_chunks[i++]; //Heap::get_at(heap.m_freed_chunks, i++);
|
|
prev->m_marked = true;
|
|
filtered.push_back(prev);
|
|
cout << filtered.back()->m_start << endl;
|
|
for (; i < heap.m_freed_chunks.size(); i++)
|
|
{
|
|
prev = filtered.back();
|
|
auto next = heap.m_freed_chunks[i]; //Heap::get_at(heap.m_freed_chunks, i);
|
|
auto p_start = (uintptr_t)(prev->m_start);
|
|
auto p_size = (uintptr_t)(prev->m_size);
|
|
auto n_start = (uintptr_t)(next->m_start);
|
|
if (n_start >= (p_start + p_size))
|
|
{
|
|
next->m_marked = true;
|
|
filtered.push_back(next);
|
|
}
|
|
}
|
|
heap.m_freed_chunks.swap(filtered);
|
|
|
|
bool profiler_enabled = heap.m_profiler_enable;
|
|
// After swap m_freed_chunks contains still available chunks
|
|
// and filtered contains all the chunks, so delete unused chunks
|
|
for (Chunk *chunk : filtered)
|
|
{
|
|
// if chunk was filtered away, delete it
|
|
if (!chunk->m_marked)
|
|
{
|
|
if (profiler_enabled)
|
|
Profiler::record(ChunkFreed, chunk);
|
|
delete chunk;
|
|
}
|
|
else
|
|
{
|
|
chunk->m_marked = false;
|
|
}
|
|
}
|
|
}
|
|
|
|
#endif
|
|
} |