Add Mesh and Task shader support to GFX (#3190)

* Bump vulkan headers

Also just use vulkan-headers as a submodule

* Add drawMeshTasks to gfx graphics pipelines

* Add DispatchMesh overload with no payload, with GLSL intrinsic

* Require spirv 1.4 for mesh shaders

* Add vulkan mesh shader feature discovery

* Add mesh shader stage bits to vk-util

* Add mesh and task shader support to render-test

* Add mesh and task tests

* Preserve "payload" specifier in task shaders

* Add mesh shader pipeline support to gfx

* Add TODO

* Add numThreads attribute for amplification stage

* Add payload to task shader test

* Drop dependency on d3dx12

* Allow passing payloads from task to mesh shaders

* regenerate vs projects

* check DispatchMesh name correctly

* Add mesh shader tests to failing tests

* Detect wave-ops feature on vulkan

* Add fuse-product to expected failures

This fails because the global varaible `count` is not initialized

* Add required extension to WaveMaskMatch SPIR-V impl

* Remove meshShader member from pipeline desc

* Identify mesh shader support on d3d12

1 files changed, 17 insertions, 4 deletions

diff --git a/source/slang/slang-emit-hlsl.cpp b/source/slang/slang-emit-hlsl.cpp
index 66902a624..9defc9adc 100644
--- a/source/slang/slang-emit-hlsl.cpp
+++ b/source/slang/slang-emit-hlsl.cpp
@@ -442,6 +442,11 @@ void HLSLSourceEmitter::emitEntryPointAttributesImpl(IRFunc* irFunc, IREntryPoin
             }
             break;
         }
+        case Stage::Amplification:
+        {
+            emitNumThreadsAttribute();
+            break;
+        }
         // TODO: There are other stages that will need this kind of handling.
         default:
             break;
@@ -1032,7 +1037,7 @@ void HLSLSourceEmitter::emitSimpleTypeImpl(IRType* type)
     }
 }
 
-void HLSLSourceEmitter::emitRateQualifiersImpl(IRRate* rate)
+void HLSLSourceEmitter::emitRateQualifiersAndAddressSpaceImpl(IRRate* rate, [[maybe_unused]] IRIntegerValue addressSpace)
 {
     if (as<IRGroupSharedRate>(rate))
     {
@@ -1138,8 +1143,11 @@ void HLSLSourceEmitter::_emitPrefixTypeAttr(IRAttr* attr)
 
 void HLSLSourceEmitter::emitSimpleFuncParamImpl(IRParam* param)
 {
-    emitRateQualifiers(param);
-    emitMeshOutputModifiers(param);
+    // A mesh shader input payload has it's own weird stuff going on, handled
+    // in emitMeshShaderModifiers, skip this bit which will introduce an
+    // invalid "groupshared" keyword.
+    if (!param->findDecoration<IRHLSLMeshPayloadDecoration>())
+        emitRateQualifiersAndAddressSpace(param);
 
     if (auto decor = param->findDecoration<IRGeometryInputPrimitiveTypeDecoration>())
     {
@@ -1200,7 +1208,7 @@ void HLSLSourceEmitter::emitPackOffsetModifier(IRInst* varInst, IRType* valueTyp
     // We emit packoffset as a semantic in `emitSemantic`, so nothing to do here.
 }
 
-void HLSLSourceEmitter::emitMeshOutputModifiersImpl(IRInst* varInst)
+void HLSLSourceEmitter::emitMeshShaderModifiersImpl(IRInst* varInst)
 {
     if(auto modifier = varInst->findDecoration<IRMeshOutputDecoration>())
     {
@@ -1212,6 +1220,11 @@ void HLSLSourceEmitter::emitMeshOutputModifiersImpl(IRInst* varInst)
         SLANG_ASSERT(s && "Unhandled type of mesh output decoration");
         m_writer->emit(s);
     }
+    if(varInst->findDecoration<IRHLSLMeshPayloadDecoration>())
+    {
+        // DXC requires that mesh payload parameters have "in" specified
+        m_writer->emit("in payload ");
+    }
 }
 
 void HLSLSourceEmitter::emitVarDecorationsImpl(IRInst* varDecl)