Implement glsl atomic's [non image or memory scope] with optional extension(s); resolves #3587 for GLSL & SPIR-V targets (#3755)

The following commit implements atomic operations & types associated with OpenGL 4.6, GL_EXT_vulkan_glsl_relaxed, GLSL_EXT_shader_atomic_float, GLSL_EXT_shader_atomic_float2, for GLSL & SPIR-V targets.

Fully implements all functions, and built-in type's, resolves https://github.com/shader-slang/slang/issues/3560 for GLSL & SPRI-V targets.

[Atomic extensions for GLSL can be found here](https://github.com/KhronosGroup/GLSL/tree/main)

Notes of worth:

* atomic_uint is well defined in GLSL->OpenGL, although was removed in GLSL->VK unless a compiler extension is supported (GL_EXT_vulkan_glsl_relaxed). This support entails transforming all atomic_uint operations and references into a storage buffer. SPIR-V has AtomicCounter+AtomicStorage (atomic_uint parallel) but does not implement these capabilities for SPIR-V->VK in any scenario. Due to the case we transform atomic_uint ourselves (GLSL_Syntax->Slang_IR) to accommodate transforming atomic_uint into valid syntax.
* GLSL_EXT_shader_atomic_float2 (all float16_t & some float/double operations) support is minimal and worth watching out for if enabling the tests. 

1 files changed, 6 insertions, 0 deletions

diff --git a/source/slang/slang-parameter-binding.cpp b/source/slang/slang-parameter-binding.cpp
index 267f23e6c..ebaa58adb 100644
--- a/source/slang/slang-parameter-binding.cpp
+++ b/source/slang/slang-parameter-binding.cpp
@@ -934,6 +934,12 @@ static void addExplicitParameterBinding(
 
         if (overlappedVarLayout)
         {
+            //legal if atomicUint
+            if(parameterInfo->varLayout->varDecl.getDecl()->getType()->astNodeType == ASTNodeType::GLSLAtomicUintType
+                && overlappedVarLayout->varDecl.getDecl()->getType()->astNodeType == ASTNodeType::GLSLAtomicUintType)
+            {
+                return;
+            }
             auto paramA = parameterInfo->varLayout->varDecl.getDecl();
             auto paramB = overlappedVarLayout->varDecl.getDecl();