Making it easier to work with shaders https://git.yummers.dev/slang.git/atom?h=master 2024-03-23T17:54:01+00:00 2024-03-23T17:54:01+00:00 Yong He yonghe@outlook.com 2024-03-23T17:54:01+00:00 urn:sha1:a23adc221b1ea26db3f3313226b629eb9e308b0f 2018-10-11T18:17:40+00:00 Tim Foley tfoleyNV@users.noreply.github.com 2018-10-11T18:17:40+00:00 urn:sha1:13c6b69cc2601ff4764f095fb45ad9573d34ff2f * Fix error when one constant is defined equal to another Fixes #666 When a user declares one constant (usually a `static const` variable) to be exactly equal to another by name: ```hlsl static const a = 999; static const b = a; ``` Then the IR-level representation of `b` is an `IRGlobalConstant` whose value expression is just a pointer to the definition of `a`. The logic in `emitIRGlobalConstantInitializer()` was trying to always call `emitIRInstExpr` to emit the value of the constant as an expression, but that function only handles complex/compound expressions and not the case of simple named values (e.g., constants like `a`). The intention is for code to call `emitIROperand()` instead, and let it decide whether to emit an expression or a named reference using its own decision-making. The `IRGlobalConstant` case really just wants to pass in the "mode" flag it uses to influence that decision-making, but shouldn't be working around it. This change just replaces the `emitIRInstExp()` call with `emitIROpernad()` and adds a test case to confirm that this fixes the reported problem. * Fixups for bugs in previous change The first problem was that certain instruction ops were being special-cased to opt out of "folding" into expressions *before* we make the universal check to always fold when inside an initializer for a global constant. The second problem is that the `emitIROperand()` logic was always putting expressions around sub-expressions, which breaks parsing when the sub-expression is an initializer list (`{...}`). This fixup is pretty much a hack, but will be something we can remove once we don't emit unncessary parentheses overall, which is a better fix.