Feature/early depth stencil (#727)

* First pass support for early depth stencil.

* Add a simple test to check if output has attributes.

* Use cross compilation to test [earlydepthstencil] on glsl.

* If target is dxil, use dxc to test against.
Add hlsl to test earlydepthstencil against.

* * Added spSessionHasCompileTargetSupport
* Made slang-test use spSessionHasCompileTargetSupport to ignore tests that cannot run

14 files changed, 141 insertions, 7 deletions

diff --git a/source/core/platform.cpp b/source/core/platform.cpp
index b96240def..d160fd37c 100644
--- a/source/core/platform.cpp
+++ b/source/core/platform.cpp
@@ -85,10 +85,13 @@ namespace Slang
 	void* h = dlopen(platformFileName, RTLD_NOW | RTLD_LOCAL);
 	if(!h)
 	{
+#if 0
+        // We can't output the error message here, because it will cause output when testing what code gen is available
 		if(auto msg = dlerror())
 		{
 			fprintf(stderr, "error: %s\n", msg);
 		}
+#endif
         return SLANG_FAIL;
 	}
     handleOut = (Handle)h;
@@ -116,4 +119,4 @@ namespace Slang
 
 #endif // _WIN32
 
-}
\ No newline at end of file
+}
diff --git a/source/slang-glslang/slang-glslang.vcxproj b/source/slang-glslang/slang-glslang.vcxproj
index 28e64e8de..eb53fc311 100644
--- a/source/slang-glslang/slang-glslang.vcxproj
+++ b/source/slang-glslang/slang-glslang.vcxproj
@@ -200,6 +200,7 @@
     <ClInclude Include="..\..\external\glslang\glslang\MachineIndependent\iomapper.h" />
     <ClInclude Include="..\..\external\glslang\glslang\MachineIndependent\localintermediate.h" />
     <ClInclude Include="..\..\external\glslang\glslang\MachineIndependent\parseVersions.h" />
+    <ClInclude Include="..\..\external\glslang\glslang\MachineIndependent\pch.h" />
     <ClInclude Include="..\..\external\glslang\glslang\MachineIndependent\preprocessor\PpContext.h" />
     <ClInclude Include="..\..\external\glslang\glslang\MachineIndependent\preprocessor\PpTokens.h" />
     <ClInclude Include="..\..\external\glslang\glslang\MachineIndependent\propagateNoContraction.h" />
@@ -242,6 +243,7 @@
     <ClCompile Include="..\..\external\glslang\glslang\MachineIndependent\limits.cpp" />
     <ClCompile Include="..\..\external\glslang\glslang\MachineIndependent\linkValidate.cpp" />
     <ClCompile Include="..\..\external\glslang\glslang\MachineIndependent\parseConst.cpp" />
+    <ClCompile Include="..\..\external\glslang\glslang\MachineIndependent\pch.cpp" />
     <ClCompile Include="..\..\external\glslang\glslang\MachineIndependent\preprocessor\Pp.cpp" />
     <ClCompile Include="..\..\external\glslang\glslang\MachineIndependent\preprocessor\PpAtom.cpp" />
     <ClCompile Include="..\..\external\glslang\glslang\MachineIndependent\preprocessor\PpContext.cpp" />
diff --git a/source/slang-glslang/slang-glslang.vcxproj.filters b/source/slang-glslang/slang-glslang.vcxproj.filters
index 2e15ff5bd..482728c71 100644
--- a/source/slang-glslang/slang-glslang.vcxproj.filters
+++ b/source/slang-glslang/slang-glslang.vcxproj.filters
@@ -111,6 +111,9 @@
     <ClInclude Include="..\..\external\glslang\glslang\MachineIndependent\parseVersions.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\external\glslang\glslang\MachineIndependent\pch.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
     <ClInclude Include="..\..\external\glslang\glslang\MachineIndependent\preprocessor\PpContext.h">
       <Filter>Header Files</Filter>
     </ClInclude>
@@ -233,6 +236,9 @@
     <ClCompile Include="..\..\external\glslang\glslang\MachineIndependent\parseConst.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\external\glslang\glslang\MachineIndependent\pch.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
     <ClCompile Include="..\..\external\glslang\glslang\MachineIndependent\preprocessor\Pp.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
diff --git a/source/slang/check.cpp b/source/slang/check.cpp
index 00c6f6dd0..e07bdf156 100644
--- a/source/slang/check.cpp
+++ b/source/slang/check.cpp
@@ -311,7 +311,10 @@ namespace Slang
             const char* libName = DefaultSharedLibraryLoader::getSharedLibraryNameFromType(type);
             if (SLANG_FAILED(sharedLibraryLoader->loadSharedLibrary(libName, sharedLibraries[int(type)].writeRef())))
             {
-                sink->diagnose(SourceLoc(), Diagnostics::failedToLoadDynamicLibrary, libName);
+                if (sink)
+                {
+                    sink->diagnose(SourceLoc(), Diagnostics::failedToLoadDynamicLibrary, libName);
+                }
                 return nullptr;
             }
         }
@@ -2072,6 +2075,11 @@ namespace Slang
                     // Has no args
                     SLANG_ASSERT(attr->args.Count() == 0);
                 }
+                else if (attr.As<EarlyDepthStencilAttribute>())
+                {
+                    // Has no args
+                    SLANG_ASSERT(attr->args.Count() == 0);
+                }
                 else
                 {
                     if(attr->args.Count() == 0)
diff --git a/source/slang/compiler.cpp b/source/slang/compiler.cpp
index cab6355c1..1e514812a 100644
--- a/source/slang/compiler.cpp
+++ b/source/slang/compiler.cpp
@@ -181,6 +181,64 @@ namespace Slang
     }
 
 
+    bool hasCodeGenTarget(Session* session, CodeGenTarget target)
+    {
+        switch (target)
+        {
+            case CodeGenTarget::Unknown:     return false;
+            case CodeGenTarget::None:       return true;
+            case CodeGenTarget::GLSL:
+            case CodeGenTarget::GLSL_Vulkan:
+            case CodeGenTarget::GLSL_Vulkan_OneDesc:
+            {
+                // Can always output GLSL
+                return true;
+            }
+            case CodeGenTarget::HLSL:
+            {
+                // Can always output HLSL
+                return true;
+            }
+            case CodeGenTarget::SPIRVAssembly:
+            case CodeGenTarget::SPIRV:
+            {
+#if SLANG_ENABLE_GLSLANG_SUPPORT
+                return session->getOrLoadSharedLibrary(Slang::SharedLibraryType::Glslang, nullptr) != nullptr;
+#else
+                return false;
+#endif
+            }            
+            case CodeGenTarget::DXBytecode:
+            case CodeGenTarget::DXBytecodeAssembly:
+            {
+#if SLANG_ENABLE_DXBC_SUPPORT
+                // Must have fxc
+                return session->getOrLoadSharedLibrary(SharedLibraryType::Fxc, nullptr) != nullptr;
+#else
+                return false;
+#endif
+            }
+
+            case CodeGenTarget::DXIL:
+            case CodeGenTarget::DXILAssembly:
+            {
+#if SLANG_ENABLE_DXIL_SUPPORT
+                // Must have dxc
+                return session->getOrLoadSharedLibrary(SharedLibraryType::Dxc, nullptr) &&
+                    session->getOrLoadSharedLibrary(SharedLibraryType::Dxil, nullptr);
+#else
+                return false;
+#endif
+            }
+
+            default:
+            {
+                SLANG_ASSERT(!"Unhandled target");
+                return false;
+            }
+        }
+    }
+
     //
 
     String emitHLSLForEntryPoint(
diff --git a/source/slang/compiler.h b/source/slang/compiler.h
index c8c242568..0eaf6e8e9 100644
--- a/source/slang/compiler.h
+++ b/source/slang/compiler.h
@@ -1,4 +1,4 @@
-#ifndef SLANG_COMPILER_H_INCLUDED
+#ifndef SLANG_COMPILER_H_INCLUDED
 #define SLANG_COMPILER_H_INCLUDED
 
 #include "../core/basic.h"
@@ -499,6 +499,9 @@ namespace Slang
         char const*     text,
         CodeGenTarget   target);
 
+    /* Returns true if a codeGen target is available. */
+    bool hasCodeGenTarget(Session* session, CodeGenTarget target);
+
     struct TypeCheckingCache;
     //
 
diff --git a/source/slang/emit.cpp b/source/slang/emit.cpp
index a3b99691d..bf98a1b24 100644
--- a/source/slang/emit.cpp
+++ b/source/slang/emit.cpp
@@ -4702,6 +4702,14 @@ struct EmitVisitor
 
             break;
         }
+        case Stage::Pixel:
+        {
+            if (irFunc->findDecoration<IREarlyDepthStencilDecoration>())
+            {
+                emit("[earlydepthstencil]\n");
+            }
+            break;
+        }
         // TODO: There are other stages that will need this kind of handling.
         default:
             break;
@@ -4709,7 +4717,7 @@ struct EmitVisitor
     }
 
     void emitIREntryPointAttributes_GLSL(
-        IRFunc*             /*irFunc*/,
+        IRFunc*             irFunc,
         EmitContext*        /*ctx*/,
         EntryPointLayout*   entryPointLayout)
     {
@@ -4805,6 +4813,15 @@ struct EmitVisitor
 
         }
         break;
+        case Stage::Pixel:
+        {
+            if (irFunc->findDecoration<IREarlyDepthStencilDecoration>())
+            {
+                // https://www.khronos.org/opengl/wiki/Early_Fragment_Test
+                emit("layout(early_fragment_tests) in;\n");
+            }
+            break;
+        }
         // TODO: There are other stages that will need this kind of handling.
         default:
             break;
diff --git a/source/slang/ir-insts.h b/source/slang/ir-insts.h
index 5cbdf326e..fc0c5f884 100644
--- a/source/slang/ir-insts.h
+++ b/source/slang/ir-insts.h
@@ -160,6 +160,11 @@ struct IRReadNoneDecoration : IRDecoration
     enum { kDecorationOp = kIRDecorationOp_ReadNone };
 };
 
+struct IREarlyDepthStencilDecoration : IRDecoration
+{
+    enum { kDecorationOp = kIRDecorationOp_EarlyDepthStencil };
+};
+
 // An instruction that specializes another IR value
 // (representing a generic) to a particular set of generic arguments 
 // (instructions representing types, witness tables, etc.)
diff --git a/source/slang/ir-serialize.cpp b/source/slang/ir-serialize.cpp
index 7e7c6c8a7..d8a01fb56 100644
--- a/source/slang/ir-serialize.cpp
+++ b/source/slang/ir-serialize.cpp
@@ -706,6 +706,7 @@ Result IRSerialWriter::write(IRModule* module, SourceManager* sourceManager, Opt
                 case kIRDecorationOp_VulkanRayPayload:
                 case kIRDecorationOp_VulkanCallablePayload:
                 case kIRDecorationOp_VulkanHitAttributes:
+                case kIRDecorationOp_EarlyDepthStencil:
                 case kIRDecorationOp_ReadNone:
                 {
                     dstInst.m_payloadType = PayloadType::Empty;
@@ -1567,6 +1568,12 @@ IRDecoration* IRSerialReader::_createDecoration(const Ser::Inst& srcInst)
             SLANG_ASSERT(srcInst.m_payloadType == PayloadType::Empty);
             return decor;
         }
+        case kIRDecorationOp_EarlyDepthStencil:
+        {
+            auto decor = createEmptyDecoration<IREarlyDepthStencilDecoration>(m_module);
+            SLANG_ASSERT(srcInst.m_payloadType == PayloadType::Empty);
+            return decor;
+        }
         case kIRDecorationOp_VulkanHitAttributes:
         {
             auto decor = createEmptyDecoration<IRVulkanHitAttributesDecoration>(m_module);
diff --git a/source/slang/ir.cpp b/source/slang/ir.cpp
index 356648212..664927e8a 100644
--- a/source/slang/ir.cpp
+++ b/source/slang/ir.cpp
@@ -2949,6 +2949,11 @@ namespace Slang
                     dump(context, "\n[__readNone]");
                 }
                 break;
+            case kIRDecorationOp_EarlyDepthStencil:
+                {
+                    dump(context, "\n[earlydepthstencil]");
+                }
+                break;
             }
         }
     }
@@ -5387,7 +5392,11 @@ namespace Slang
                     context->builder->addDecoration<IRVulkanCallablePayloadDecoration>(clonedValue);
                 }
                 break;
-
+            case kIRDecorationOp_EarlyDepthStencil:
+                {
+                    context->builder->addDecoration<IREarlyDepthStencilDecoration>(clonedValue);
+                }
+                break;
             case kIRDecorationOp_VulkanHitAttributes:
                 {
                     context->builder->addDecoration<IRVulkanHitAttributesDecoration>(clonedValue);
diff --git a/source/slang/ir.h b/source/slang/ir.h
index b3c690c26..b8c8e85f2 100644
--- a/source/slang/ir.h
+++ b/source/slang/ir.h
@@ -160,6 +160,8 @@ enum IRDecorationOp : uint16_t
     kIRDecorationOp_ReadNone,
     kIRDecorationOp_VulkanCallablePayload,
 
+    kIRDecorationOp_EarlyDepthStencil,
+
     kIRDecorationOp_CountOf
 };
 
diff --git a/source/slang/lower-to-ir.cpp b/source/slang/lower-to-ir.cpp
index 4f40b4af6..1390cddaf 100644
--- a/source/slang/lower-to-ir.cpp
+++ b/source/slang/lower-to-ir.cpp
@@ -5146,6 +5146,11 @@ struct DeclLoweringVisitor : DeclVisitor<DeclLoweringVisitor, LoweredValInfo>
             getBuilder()->addDecoration<IRReadNoneDecoration>(irFunc);
         }
 
+        if (decl->FindModifier<EarlyDepthStencilAttribute>())
+        {
+            getBuilder()->addDecoration<IREarlyDepthStencilDecoration>(irFunc);
+        }
+
         // For convenience, ensure that any additional global
         // values that were emitted while outputting the function
         // body appear before the function itself in the list
diff --git a/source/slang/modifier-defs.h b/source/slang/modifier-defs.h
index f6f55ecbd..5c86301ad 100644
--- a/source/slang/modifier-defs.h
+++ b/source/slang/modifier-defs.h
@@ -327,6 +327,7 @@ SIMPLE_SYNTAX_CLASS(FlattenAttribute, Attribute)            // `[flatten]`
 SIMPLE_SYNTAX_CLASS(ForceCaseAttribute, Attribute)          // `[forcecase]`
 SIMPLE_SYNTAX_CLASS(CallAttribute, Attribute)               // `[call]`
 
+
 // [[vk_push_constant]] [[push_constant]]
 SIMPLE_SYNTAX_CLASS(PushConstantAttribute, Attribute)
 
@@ -348,7 +349,7 @@ SYNTAX_CLASS(PatchConstantFuncAttribute, Attribute)
 END_SYNTAX_CLASS()
 SIMPLE_SYNTAX_CLASS(DomainAttribute, Attribute)
 
-SIMPLE_SYNTAX_CLASS(EarlyDepthStencilAttribute, Attribute)
+SIMPLE_SYNTAX_CLASS(EarlyDepthStencilAttribute, Attribute)  // `[earlydepthstencil]`
 
 // An HLSL `[numthreads(x,y,z)]` attribute
 SYNTAX_CLASS(NumThreadsAttribute, Attribute)
diff --git a/source/slang/slang.cpp b/source/slang/slang.cpp
index 28b504831..ef71430fc 100644
--- a/source/slang/slang.cpp
+++ b/source/slang/slang.cpp
@@ -1,4 +1,4 @@
-#include "../../slang.h"
+#include "../../slang.h"
 
 #include "../core/slang-io.h"
 #include "../core/slang-string-util.h"
@@ -1147,6 +1147,14 @@ SLANG_API ISlangSharedLibraryLoader* spSessionGetSharedLibraryLoader(
     return (s->sharedLibraryLoader == Slang::DefaultSharedLibraryLoader::getSingleton()) ? nullptr : s->sharedLibraryLoader.get();
 }
 
+SLANG_API SlangResult spSessionHasCompileTargetSupport(
+    SlangSession*                session,
+    SlangCompileTarget           target)
+{
+    auto s = SESSION(session);
+    return Slang::hasCodeGenTarget(s, Slang::CodeGenTarget(target)) ? SLANG_OK : SLANG_FAIL;
+}
+
 SLANG_API SlangCompileRequest* spCreateCompileRequest(
     SlangSession* session)
 {