Merge pull request #10996 from Kelebek1/readblock_optimisation

Use spans over guest memory where possible instead of copying data

src/common/page_table.cpp

@@ -66,6 +66,7 @@ void PageTable::Resize(std::size_t address_space_width_in_bits, std::size_t page
                                              << (address_space_width_in_bits - page_size_in_bits)};
     pointers.resize(num_page_table_entries);
     backing_addr.resize(num_page_table_entries);
+    blocks.resize(num_page_table_entries);
     current_address_space_width_in_bits = address_space_width_in_bits;
     page_size = 1ULL << page_size_in_bits;
 }

src/common/page_table.h

@@ -122,6 +122,7 @@ struct PageTable {
      * corresponding attribute element is of type `Memory`.
      */
     VirtualBuffer<PageInfo> pointers;
+    VirtualBuffer<u64> blocks;
 
     VirtualBuffer<u64> backing_addr;
 

src/common/scratch_buffer.h

@@ -40,8 +40,21 @@ public:
     ~ScratchBuffer() = default;
     ScratchBuffer(const ScratchBuffer&) = delete;
     ScratchBuffer& operator=(const ScratchBuffer&) = delete;
-    ScratchBuffer(ScratchBuffer&&) = default;
-    ScratchBuffer& operator=(ScratchBuffer&&) = default;
+
+    ScratchBuffer(ScratchBuffer&& other) noexcept {
+        swap(other);
+        other.last_requested_size = 0;
+        other.buffer_capacity = 0;
+        other.buffer.reset();
+    }
+
+    ScratchBuffer& operator=(ScratchBuffer&& other) noexcept {
+        swap(other);
+        other.last_requested_size = 0;
+        other.buffer_capacity = 0;
+        other.buffer.reset();
+        return *this;
+    }
 
     /// This will only grow the buffer's capacity if size is greater than the current capacity.
     /// The previously held data will remain intact.