Avoid minimum integer literals in HLSL (and remaining ones in MSL) #7504
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…-negative value minus one As we did for MSL in gfx-rs#7437. eg `-2147483648` becomes `-2147483647 - 1`. Neither FXC nor DXC currently have any issues parsing the most negative value literals. However, we have been informed this is not guaranteed to always be the case, so are making this change as a precaution.
… and modulo avoid using minimum value literals As we know that minimum value integer literals can cause problems for some compilers. (See gfx-rs#7437) Make the code which generates these functions call msl::Writer::put_literal() and hlsl::Writer::write_literal() respectively to output the minimum value integer literals instead of just writing them directly, ensuring we only have to handle this workaround in a single location (per backend).
ErichDonGubler
approved these changes
Apr 10, 2025
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Connections
Follow up from #7437
Description
DXC and FXC currently can parse the most negative value integer literals fine (unlike the metal compiler). However, we have been informed on the DX discord that this is not guaranteed. So let's avoid them on HLSL too just to be safe.
Additionally we need to update the workarounds for signed integer division and modulo to avoid using them.
Testing
Snapshots cover it well
Squash or Rebase?
Rebase plz
Checklist
cargo fmt.cargo clippy --tests. If applicable, add:cargo xtask testto run tests.