On all platforms, this would result in out of bounds accesses when getting the component sizes (which uses stuff from VertexLoader_Position.h/VertexLoader_TextCoord.h/VertexLoader_Normal.h). On platforms other than x64 and ARM64, this would also be out of bounds accesses when getting function pointers for the non-JIT vertex loader (in VertexLoader_Position.cpp etc.). Usually both of these would get data from other entries in the same multi-dimensional array, but the last few entries would be truly out of bounds. This does mean that an out of bounds function pointer can be called on platforms that don't have a JIT vertex loader, but it is limited to invalid component formats with values 5/6/7 due to the size of the bitfield the formats come from, so it seems unlikely that this could be exploited in practice.
This issue affects a few games; Def Jam: Fight for New York (https://bugs.dolphin-emu.org/issues/12719) and Fifa Street are known to be affected.
I have not done any hardware testing for this PR specifically, though I *think* I previously determined that at least a value of 5 behaves the same as float (4). That's what I implemented in any case. I did previously determine that both Def Jam: Fight for New York and Fifa Street use an invalid normal format, but don't actually have lighting enabled when that normal vector is used, so it doesn't change rendering in practice.
The color component format also has two invalid values, but VertexLoader_Color.h/.cpp do check for those invalid ones and return a default value instead of doing an out of bounds access.
This is the behavior in the x64 and ARM64 vertex loaders. I don't know if it makes sense (the whole skipped vertex system seems jank, but several games behave incorrectly without it).
DataReader is generally jank - it has a start and end pointer, but the end pointer is generally not used, and all of the vertex loaders mostly bypassed it anyways.
Wrapper code (the vertex loaer test, as well as Fifo.cpp and OpcodeDecoding.cpp) still uses it, as does the software vertex loader (which is not a subclass of VertexLoader). These can probably be eliminated later.
I originally added these in 2b1d1038a6, for both the TPipelineFunction and the size. The size was moved into the header in fdcd2b7d00 (making the size functions obsolete), but it seems that the functions themselves are no longer needed now.
I think I didn't use this approach before because it would have required ComponentFormatTable and ComponentCountRow to be templated, which would end up resulting in lines that were too long and thus wrapped in awkward places. (I *think* they didn't get inferred properly.) Now that we only need TPipelineFunction, the templating is not needed, and this ends up being a more readable version of the version with the wrapper functions.
This more accurately represents what's going on, and also ends at 0 instead of 1, making some indexing operations easier. This also changes it so that position_matrix_index_cache actually starts from index 0 instead of index 1.
SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
Additionally, VCacheEnhance has been added to UVAT_group1. According to YAGCD, this field is always 1.
TVtxDesc also now has separate low and high fields whose hex values correspond with the proper registers, instead of having one 33-bit value. This change was made in a way that should be backwards-compatible.
We can use u32 instead of unsigned int to shorten up these definitions
and make them much nicer to read.
While we're at it, change the size array to house u32 elements to match
the return value of the function.
This moves all the byte swapping utilities into a header named Swap.h.
A dedicated header is much more preferable here due to the size of the
code itself. In general usage throughout the codebase, CommonFuncs.h was
generally only included for these functions anyway. These being in their
own header avoids dumping the lesser used utilities into scope. As well
as providing a localized area for more utilities related to byte
swapping in the future (should they be needed). This also makes it nicer
to identify which files depend on the byte swapping utilities in
particular.
Since this is a completely new header, moving the code uncovered a few
indirect includes, as well as making some other inclusions unnecessary.
This is required to make packing consistent between compilers: with u32, MSVC
would not allocate a bitfield that spans two u32s (it would leave a "hole").
Pokechu22