slang.git - Making it easier to work with shaders

	Commit message (Collapse)	Author	Age
*	Remove non-IR codegen paths (#398)	Tim Foley	2018-02-03
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	The basic change is simple: remove support for all code generation paths other than the IR. There is a lot of vestigial code left, but the main logic in `ast-legalize.` is gone. Doing this breaks a lot* of tests, for various reasons: - We can no longer guarantee exactly matching DXBC or SPIR-V output after things pass through out IR - Many builtins don't have matching versions defined for GLSL output via IR (even when they had versions defined via the earlier approach that worked with the AST) - A lot of code creates intermediate values of opaque types in the IR, which turn into opaque-type temporaries that aren't allowed (this breaks many GLSL tests, but also some HLSL) I implemented some small fixes for issues that I could get working in the time I had, but most of the above are larger than made sense to fix in this commit. For now I'm disabling the tests that cause problems, but we will need to make a concerted effort to get things working on this new substrate if we are going to make good on our goals.
*	Fixup for the glslang bug workaround	Tim Foley	2017-07-23
\| \| \| \| \| \|	There was a bug where the intialization expression for a variable was being lowered after the declaration was added to the output code, so that any sub-expressions that get hoisted out actually get computed after the original variable. This obviously led to downstream compilation failure. I've updated the test case to stress this scenario.
*	Work around glslang issue 988	Tim Foley	2017-07-23
	The basic bug there is that if you have a member of `struct` type in a `uniform` block and then pass a reference to that member directly to a call: ``` struct Foo { vec4 bar; }; uniform U { Foo foo; }; void main() { doSomething(foo); } ``` then glslang generates invalid SPIR-V which seems to cause an issue for some drivers. This change works around the problem by detecting cases where an argument to a function call is a reference to `uniform` block member (of `struct` type) and then rewrites the code to move that value to a temporary before the call.