7 files changed, 54 insertions, 35 deletions

diff --git a/src/core/hle/kernel/physical_memory.h b/src/core/hle/kernel/physical_memory.h
index 090565310..b689e8e8b 100644
--- a/src/core/hle/kernel/physical_memory.h
+++ b/src/core/hle/kernel/physical_memory.h
@@ -14,6 +14,9 @@ namespace Kernel {
 // - Second to ensure all host backing memory used is aligned to 256 bytes due
 // to strict alignment restrictions on GPU memory.
 
-using PhysicalMemory = std::vector<u8, Common::AlignmentAllocator<u8, 256>>;
+using PhysicalMemoryVector = std::vector<u8, Common::AlignmentAllocator<u8, 256>>;
+class PhysicalMemory final : public PhysicalMemoryVector {
+    using PhysicalMemoryVector::PhysicalMemoryVector;
+};
 
 } // namespace Kernel
diff --git a/src/core/hle/kernel/vm_manager.cpp b/src/core/hle/kernel/vm_manager.cpp
index a9a20ef76..0b3500fce 100644
--- a/src/core/hle/kernel/vm_manager.cpp
+++ b/src/core/hle/kernel/vm_manager.cpp
@@ -3,6 +3,7 @@
 // Refer to the license.txt file included.
 
 #include <algorithm>
+#include <cstring>
 #include <iterator>
 #include <utility>
 #include "common/alignment.h"
@@ -269,18 +270,9 @@ ResultVal<VAddr> VMManager::SetHeapSize(u64 size) {
     // If necessary, expand backing vector to cover new heap extents in
     // the case of allocating. Otherwise, shrink the backing memory,
     // if a smaller heap has been requested.
-    const u64 old_heap_size = GetCurrentHeapSize();
-    if (size > old_heap_size) {
-        const u64 alloc_size = size - old_heap_size;
-
-        heap_memory->insert(heap_memory->end(), alloc_size, 0);
-        RefreshMemoryBlockMappings(heap_memory.get());
-    } else if (size < old_heap_size) {
-        heap_memory->resize(size);
-        heap_memory->shrink_to_fit();
-
-        RefreshMemoryBlockMappings(heap_memory.get());
-    }
+    heap_memory->resize(size);
+    heap_memory->shrink_to_fit();
+    RefreshMemoryBlockMappings(heap_memory.get());
 
     heap_end = heap_region_base + size;
     ASSERT(GetCurrentHeapSize() == heap_memory->size());
@@ -752,24 +744,20 @@ void VMManager::MergeAdjacentVMA(VirtualMemoryArea& left, const VirtualMemoryAre
     // Always merge allocated memory blocks, even when they don't share the same backing block.
     if (left.type == VMAType::AllocatedMemoryBlock &&
         (left.backing_block != right.backing_block || left.offset + left.size != right.offset)) {
-        const auto right_begin = right.backing_block->begin() + right.offset;
-        const auto right_end = right_begin + right.size;
 
         // Check if we can save work.
         if (left.offset == 0 && left.size == left.backing_block->size()) {
             // Fast case: left is an entire backing block.
-            left.backing_block->insert(left.backing_block->end(), right_begin, right_end);
+            left.backing_block->resize(left.size + right.size);
+            std::memcpy(left.backing_block->data() + left.size,
+                        right.backing_block->data() + right.offset, right.size);
         } else {
             // Slow case: make a new memory block for left and right.
-            const auto left_begin = left.backing_block->begin() + left.offset;
-            const auto left_end = left_begin + left.size;
-            const auto left_size = static_cast<std::size_t>(std::distance(left_begin, left_end));
-            const auto right_size = static_cast<std::size_t>(std::distance(right_begin, right_end));
-
             auto new_memory = std::make_shared<PhysicalMemory>();
-            new_memory->reserve(left_size + right_size);
-            new_memory->insert(new_memory->end(), left_begin, left_end);
-            new_memory->insert(new_memory->end(), right_begin, right_end);
+            new_memory->resize(left.size + right.size);
+            std::memcpy(new_memory->data(), left.backing_block->data() + left.offset, left.size);
+            std::memcpy(new_memory->data() + left.size, right.backing_block->data() + right.offset,
+                        right.size);
 
             left.backing_block = std::move(new_memory);
             left.offset = 0;
@@ -792,8 +780,7 @@ void VMManager::UpdatePageTableForVMA(const VirtualMemoryArea& vma) {
         memory.UnmapRegion(page_table, vma.base, vma.size);
         break;
     case VMAType::AllocatedMemoryBlock:
-        memory.MapMemoryRegion(page_table, vma.base, vma.size,
-                               vma.backing_block->data() + vma.offset);
+        memory.MapMemoryRegion(page_table, vma.base, vma.size, *vma.backing_block, vma.offset);
         break;
     case VMAType::BackingMemory:
         memory.MapMemoryRegion(page_table, vma.base, vma.size, vma.backing_memory);
diff --git a/src/core/loader/elf.cpp b/src/core/loader/elf.cpp
index f1795fdd6..8908e5328 100644
--- a/src/core/loader/elf.cpp
+++ b/src/core/loader/elf.cpp
@@ -335,7 +335,8 @@ Kernel::CodeSet ElfReader::LoadInto(VAddr vaddr) {
             codeset_segment->addr = segment_addr;
             codeset_segment->size = aligned_size;
 
-            memcpy(&program_image[current_image_position], GetSegmentPtr(i), p->p_filesz);
+            std::memcpy(program_image.data() + current_image_position, GetSegmentPtr(i),
+                        p->p_filesz);
             current_image_position += aligned_size;
         }
     }
diff --git a/src/core/loader/kip.cpp b/src/core/loader/kip.cpp
index 474b55cb1..092103abe 100644
--- a/src/core/loader/kip.cpp
+++ b/src/core/loader/kip.cpp
@@ -2,6 +2,7 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
+#include <cstring>
 #include "core/file_sys/kernel_executable.h"
 #include "core/file_sys/program_metadata.h"
 #include "core/gdbstub/gdbstub.h"
@@ -76,8 +77,8 @@ AppLoader::LoadResult AppLoader_KIP::Load(Kernel::Process& process) {
         segment.addr = offset;
         segment.offset = offset;
         segment.size = PageAlignSize(static_cast<u32>(data.size()));
-        program_image.resize(offset);
-        program_image.insert(program_image.end(), data.begin(), data.end());
+        program_image.resize(offset + data.size());
+        std::memcpy(program_image.data() + offset, data.data(), data.size());
     };
 
     load_segment(codeset.CodeSegment(), kip->GetTextSection(), kip->GetTextOffset());
diff --git a/src/core/loader/nso.cpp b/src/core/loader/nso.cpp
index f629892ae..515c5accb 100644
--- a/src/core/loader/nso.cpp
+++ b/src/core/loader/nso.cpp
@@ -3,6 +3,7 @@
 // Refer to the license.txt file included.
 
 #include <cinttypes>
+#include <cstring>
 #include <vector>
 
 #include "common/common_funcs.h"
@@ -96,8 +97,9 @@ std::optional<VAddr> AppLoader_NSO::LoadModule(Kernel::Process& process,
         if (nso_header.IsSegmentCompressed(i)) {
             data = DecompressSegment(data, nso_header.segments[i]);
         }
-        program_image.resize(nso_header.segments[i].location);
-        program_image.insert(program_image.end(), data.begin(), data.end());
+        program_image.resize(nso_header.segments[i].location + data.size());
+        std::memcpy(program_image.data() + nso_header.segments[i].location, data.data(),
+                    data.size());
         codeset.segments[i].addr = nso_header.segments[i].location;
         codeset.segments[i].offset = nso_header.segments[i].location;
         codeset.segments[i].size = PageAlignSize(static_cast<u32>(data.size()));
@@ -139,12 +141,12 @@ std::optional<VAddr> AppLoader_NSO::LoadModule(Kernel::Process& process,
         std::vector<u8> pi_header;
         pi_header.insert(pi_header.begin(), reinterpret_cast<u8*>(&nso_header),
                          reinterpret_cast<u8*>(&nso_header) + sizeof(NSOHeader));
-        pi_header.insert(pi_header.begin() + sizeof(NSOHeader), program_image.begin(),
-                         program_image.end());
+        pi_header.insert(pi_header.begin() + sizeof(NSOHeader), program_image.data(),
+                         program_image.data() + program_image.size());
 
         pi_header = pm->PatchNSO(pi_header, file.GetName());
 
-        std::copy(pi_header.begin() + sizeof(NSOHeader), pi_header.end(), program_image.begin());
+        std::copy(pi_header.begin() + sizeof(NSOHeader), pi_header.end(), program_image.data());
     }
 
     // Apply cheats if they exist and the program has a valid title ID
diff --git a/src/core/memory.cpp b/src/core/memory.cpp
index 3c2a29d9b..f0888327f 100644
--- a/src/core/memory.cpp
+++ b/src/core/memory.cpp
@@ -14,6 +14,7 @@
 #include "common/swap.h"
 #include "core/arm/arm_interface.h"
 #include "core/core.h"
+#include "core/hle/kernel/physical_memory.h"
 #include "core/hle/kernel/process.h"
 #include "core/hle/kernel/vm_manager.h"
 #include "core/memory.h"
@@ -38,6 +39,11 @@ struct Memory::Impl {
         system.ArmInterface(3).PageTableChanged(*current_page_table, address_space_width);
     }
 
+    void MapMemoryRegion(Common::PageTable& page_table, VAddr base, u64 size,
+                         Kernel::PhysicalMemory& memory, VAddr offset) {
+        MapMemoryRegion(page_table, base, size, memory.data() + offset);
+    }
+
     void MapMemoryRegion(Common::PageTable& page_table, VAddr base, u64 size, u8* target) {
         ASSERT_MSG((size & PAGE_MASK) == 0, "non-page aligned size: {:016X}", size);
         ASSERT_MSG((base & PAGE_MASK) == 0, "non-page aligned base: {:016X}", base);
@@ -601,6 +607,11 @@ void Memory::SetCurrentPageTable(Kernel::Process& process) {
     impl->SetCurrentPageTable(process);
 }
 
+void Memory::MapMemoryRegion(Common::PageTable& page_table, VAddr base, u64 size,
+                             Kernel::PhysicalMemory& memory, VAddr offset) {
+    impl->MapMemoryRegion(page_table, base, size, memory, offset);
+}
+
 void Memory::MapMemoryRegion(Common::PageTable& page_table, VAddr base, u64 size, u8* target) {
     impl->MapMemoryRegion(page_table, base, size, target);
 }
diff --git a/src/core/memory.h b/src/core/memory.h
index 1428a6d60..8913a9da4 100644
--- a/src/core/memory.h
+++ b/src/core/memory.h
@@ -19,8 +19,9 @@ class System;
 }
 
 namespace Kernel {
+class PhysicalMemory;
 class Process;
-}
+} // namespace Kernel
 
 namespace Memory {
 
@@ -66,6 +67,19 @@ public:
     void SetCurrentPageTable(Kernel::Process& process);
 
     /**
+     * Maps an physical buffer onto a region of the emulated process address space.
+     *
+     * @param page_table The page table of the emulated process.
+     * @param base       The address to start mapping at. Must be page-aligned.
+     * @param size       The amount of bytes to map. Must be page-aligned.
+     * @param memory     Physical buffer with the memory backing the mapping. Must be of length
+     *                   at least `size + offset`.
+     * @param offset     The offset within the physical memory. Must be page-aligned.
+     */
+    void MapMemoryRegion(Common::PageTable& page_table, VAddr base, u64 size,
+                         Kernel::PhysicalMemory& memory, VAddr offset);
+
+    /**
      * Maps an allocated buffer onto a region of the emulated process address space.
      *
      * @param page_table The page table of the emulated process.