Making it easier to work with shaders https://git.yummers.dev/slang.git/atom?h=master 2019-03-25T21:39:13+00:00 2019-03-25T21:39:13+00:00 Tim Foley tfoleyNV@users.noreply.github.com 2019-03-25T21:39:13+00:00 urn:sha1:bedcb920045dd68f522e29d90fc3804f84bc08d0 An `enum` case currently lowers to the IR as the value of its tag expression, so if we have: ```hlsl enum E { X = 99, } ``` then `X` will lower as IR for the expression `99` which is just a literal. If instead we have: ```hlsl enum E { X = 99u, } ``` then after type checking the expression is `int(99u)`, which will get emitted to the global (module) scope as a cast/conversion instruction, that then gets referenced at the use sites of `E.X`. The emit logic wasn't set up to handle the case of referencing something directly from the global scope, so this change makes it so that side-effect-free global instructions are treated just like literal constants. This simple handling is fine for now since it will only apply to `enum` tag values (true global constants declared with `static const` have different handling).