Add GLSL Compatibility. (#3321)

* Parse glsl buffer blocks to GLSLInterfaceBlockDecl

* Parse glsl local size layout declarations

* Parse (and ignore) glsl version directives

* spelling

* Better l-value interpretation for glsl interface blocks

* Better l-value interpretation for glsl interface blocks

* Add compile flag for enabling glsl

* Parse and ignore precision modifiers.

* Automatically import `glsl` module for compatiblity.

* Complete vector and matrix types for glsl

* Remove generated file from repo

* Bump .gitignore

* do not mark out globals as params

* Synthesize entrypoint layout from global inout vars.

* update test result.

* Allow HLSL semantic on global variables.

* Fix.

* Fix test.

* Fix win32 compile error.

* Add more builtin input/output and texture intrinsics.

* Add struct/array constructor syntax.

* Skip `#extension` lines.

* overide operator * for matrix/vector multiplication.

* Add `matrixCompMult`.

* Parse modifiers in for loop init var declr.

* Add more glsl intrinsics, add stage into to var layout.

* Allow `int[3] x` syntax.

* Fix array type syntax.

---------

Co-authored-by: Ellie Hermaszewska <ellieh@nvidia.com>
Co-authored-by: Yong He <yhe@nvidia.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/source/slang/slang-check-decl.cpp b/source/slang/slang-check-decl.cpp
index 8d7337318..c31c94a85 100644
--- a/source/slang/slang-check-decl.cpp
+++ b/source/slang/slang-check-decl.cpp
@@ -389,6 +389,11 @@ namespace Slang
         //
         if(decl->hasModifier<HLSLStaticModifier>()) return false;
 
+        // While not normally allowed, out variables are not constant
+        // parameters, this can happen for example in GLSL mode
+        if(decl->hasModifier<OutModifier>()) return false;
+        if(decl->hasModifier<InModifier>()) return false;
+
         // The `groupshared` modifier indicates that a variable cannot
         // be a shader parameters, but is instead transient storage
         // allocated for the duration of a thread-group's execution.
@@ -1219,6 +1224,22 @@ namespace Slang
                     varDecl->type.type = m_astBuilder->getConstantBufferType(varDecl->type);
                 }
             }
+
+            if (getLinkage()->getAllowGLSLInput())
+            {
+                // If we are in GLSL compatiblity mode, we want to treat all global variables
+                // without any `uniform` modifiers as true global variables by default.
+                if (!varDecl->findModifier<HLSLUniformModifier>() &&
+                    !varDecl->findModifier<InModifier>() &&
+                    !varDecl->findModifier<OutModifier>())
+                {
+                    if (!as<ResourceType>(varDecl->type) && !as<PointerLikeType>(varDecl->type))
+                    {
+                        auto staticModifier = m_astBuilder->create<HLSLStaticModifier>();
+                        addModifier(varDecl, staticModifier);
+                    }
+                }
+            }
         }
     }