The current way were doing it would require copying a 768 character
buffer (part of the Entry struct) to the new element in the vector.
Given it's a plain array, std::move won't eliminate that.
Instead, we can emplace an instance directly into the destination buffer
and then fill it out, avoiding the need to perform any unnecessary
copies.
Given this is done in a loop, we can request the destination to allocate
all of the necessary memory ahead of time, avoiding the need to
potentially keep reallocating over and over on every few insertions into
the vector.
We don't need to use a std::string here, given all that's done is
comparing the character sequence against another. This allows passing
regular const char* without needing to heap allocate.
These members don't need to be entirely exposed, we can instead expose
an API to operate on them without directly needing to mutate them
We can also guard against overflow/API misuse this way as well, given
active_sessions is an unsigned value.
All calling code assumes that the rasterizer will be in a valid state,
which is a totally fine assumption. The only way the rasterizer wouldn't
be is if initialization is done incorrectly or fails, which is checked
against in System::Init().
We move the initialization of the renderer to the core class, while
keeping the creation of it and any other specifics in video_core. This
way we can ensure that the renderer is initialized and doesn't give
unfettered access to the renderer. This also makes dependencies on types
more explicit.
For example, the GPU class doesn't need to depend on the
existence of a renderer, it only needs to care about whether or not it
has a rasterizer, but since it was accessing the global variable, it was
also making the renderer a part of its dependency chain. By adjusting
the interface, we can get rid of this dependency.
This amends cases where crashes can occur that were missed due to the
odd way the previous code was set up (using 3DS memory regions that
don't exist).
Using member variables for referencing the segments array increases the
size of the class in memory for little benefit. The same behavior can be
achieved through the use of accessors that just return the relevant
segment.
Avoids using a u32 to compare against a range of size_t, which can be a
source of warnings. While we're at it, compress a std::tie into a
structured binding.
General moving to keep kernel object types separate from the direct
kernel code. Also essentially a preliminary cleanup before eliminating
global kernel state in the kernel code.
Zach Hilman