yuzu-mainline/src/common/page_table.cpp
Fernando Sahmkow 27cbb75e7c PageTable: move backing addresses to a children class as the CPU page table does not need them.
This PR aims to reduce the memory usage in the CPU page table by moving
GPU specific parameters into a child class. This saves 1Gb of Memory for
most games.
2020-03-14 09:43:57 -04:00

42 lines
1.6 KiB
C++

// Copyright 2019 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include "common/page_table.h"
namespace Common {
PageTable::PageTable(std::size_t page_size_in_bits) : page_size_in_bits{page_size_in_bits} {}
PageTable::~PageTable() = default;
void PageTable::Resize(std::size_t address_space_width_in_bits) {
const std::size_t num_page_table_entries = 1ULL
<< (address_space_width_in_bits - page_size_in_bits);
pointers.resize(num_page_table_entries);
attributes.resize(num_page_table_entries);
// The default is a 39-bit address space, which causes an initial 1GB allocation size. If the
// vector size is subsequently decreased (via resize), the vector might not automatically
// actually reallocate/resize its underlying allocation, which wastes up to ~800 MB for
// 36-bit titles. Call shrink_to_fit to reduce capacity to what's actually in use.
pointers.shrink_to_fit();
attributes.shrink_to_fit();
}
BackingPageTable::BackingPageTable(std::size_t page_size_in_bits) : PageTable{page_size_in_bits} {}
BackingPageTable::~BackingPageTable() = default;
void BackingPageTable::Resize(std::size_t address_space_width_in_bits) {
PageTable::Resize(address_space_width_in_bits);
const std::size_t num_page_table_entries = 1ULL
<< (address_space_width_in_bits - page_size_in_bits);
backing_addr.resize(num_page_table_entries);
backing_addr.shrink_to_fit();
}
} // namespace Common