ATOM operates atomically on global memory. For now only add ATOM.ADD
since that's what was found in commercial games.
This asserts for ATOM.ADD.S32 (handling the others as unimplemented),
although ATOM.ADD.U32 shouldn't be any different.
This change forces us to change the default type on SPIR-V storage
buffers from float to uint. We could also alias the buffers, but it's
simpler for now to just use uint. While we are at it, abstract the code
to avoid repetition.
Using the same technique we used for u8 on LDG, implement u16.
In the case of STG, load memory and insert the value we want to set
into it with bitfieldInsert. Then set that value.
This commit introduces a mechanism by which shader IR code can be
amended and extended. This useful for track algorithms where certain
information can derived from before the track such as indexes to array
samplers.
LDG can load single bytes instead of full integers or packs of integers.
These have the advantage of loading bytes that are not aligned to 4
bytes.
To emulate these this commit gets the byte being referenced (by doing
"address & 3" and then using that to extract the byte from the loaded
integer:
result = bitfieldExtract(loaded_integer, (address % 4) * 8, 8)
I2F's byte selector is used to choose what bytes to convert to float.
e.g. if the input is 0xaabbccdd and the selector is ".B3" it will
convert 0xaa. The default (when it's not shown in nvdisasm) is ".B0", in
that example the default would convert 0xdd to float.
When a image format mismatches we were inserting zeroes to the texture
itself. This was not handling cases were the mismatch uses less
coordinates than the guest shader code. Address that by resizing the
vector.
Some games like "Fire Emblem: Three Houses" bind 2D textures to offsets
used by instructions of 1D textures. To handle the discrepancy this
commit uses the the texture type from the binding and modifies the
emitted code IR to build a valid backend expression.
E.g.: Bound texture is 2D and instruction is 1D, the emitted IR samples
a 2D texture in the coordinate ivec2(X, 0).
While DEPBAR is stubbed it doesn't change anything from our end. Shading
languages handle what this instruction does implicitly. We are not
getting anything out fo this log except noise.
