Fix up emission of shader parameter semantics when using IR (#226)

* Fix up emission of shader parameter semantics when using IR

- Make sure to propagate entry point parameter layouts down to IR parameters when doing the initial cloning to form target-specific IR

- When layout information is present on an IR node, prefer to use that over the original high-level declaration for outputting semantics in final HLSL

- Fix up test runner to generate `.actual` files when running compute tests, in cases where the `render-test` application errors out (e.g., because of a Slang compilation error)

- Add a first test of generics functionality, to show that they generate valid code through the IR
  - Right now this test is *not* using any "interesting" operations on the type parameter, so this is not a test that can confirm that interface constraints work

* fixup: skip compute tests when running on Linux

4 files changed, 58 insertions, 1 deletions

diff --git a/source/slang/emit.cpp b/source/slang/emit.cpp
index 971f0345b..1b5db065f 100644
--- a/source/slang/emit.cpp
+++ b/source/slang/emit.cpp
@@ -5090,6 +5090,37 @@ emitDeclImpl(decl, nullptr);
         EmitContext*    context,
         IRValue*         inst)
     {
+        // Don't emit semantics if we aren't translating down to HLSL
+        switch (context->shared->target)
+        {
+        case CodeGenTarget::HLSL:
+            break;
+
+        default:
+            return;
+        }
+
+        if(auto layoutDecoration = inst->findDecoration<IRLayoutDecoration>())
+        {
+            if(auto varLayout = layoutDecoration->layout.As<VarLayout>())
+            {
+                if(varLayout->flags & VarLayoutFlag::HasSemantic)
+                {
+                    Emit(" : ");
+                    emit(varLayout->semanticName);
+                    if(varLayout->semanticIndex)
+                    {
+                        Emit(varLayout->semanticIndex);
+                    }
+
+                    return;
+                }
+            }
+        }
+
+        // TODO(tfoley): should we ever need to use the high-level declaration
+        // for this? It seems like the wrong approach...
+
         auto decoration = inst->findDecoration<IRHighLevelDeclDecoration>();
         if( decoration )
         {
diff --git a/source/slang/glsl.meta.slang.h b/source/slang/glsl.meta.slang.h
index e43a51ea9..a4aade3c2 100644
--- a/source/slang/glsl.meta.slang.h
+++ b/source/slang/glsl.meta.slang.h
@@ -173,7 +173,7 @@ sb << "syntax patch : GLSLPatchModifier;\n";
 // [GLSL 4.5] Interpolation Qualifiers
 sb << "syntax smooth : SimpleModifier;\n";
 sb << "syntax flat : SimpleModifier;\n";
-sb << "syntax noperspectie : SimpleModifier;\n";
+sb << "syntax noperspective : SimpleModifier;\n";
 
 
 // [GLSL 4.3.2] Constant Qualifier
diff --git a/source/slang/ir.cpp b/source/slang/ir.cpp
index 5ace50397..4c01e4fc1 100644
--- a/source/slang/ir.cpp
+++ b/source/slang/ir.cpp
@@ -3094,6 +3094,31 @@ namespace Slang
             clonedFunc,
             entryPointLayout);
 
+        // We will also go on and attach layout information
+        // to the function parameters, so that we have it
+        // available directly on the parameters, rather
+        // than having to look it up on the original entry-point layout.
+        if( auto firstBlock = clonedFunc->getFirstBlock() )
+        {
+            UInt paramLayoutCount = entryPointLayout->fields.Count();
+            UInt paramCounter = 0;
+            for( auto pp = firstBlock->getFirstParam(); pp; pp = pp->getNextParam() )
+            {
+                UInt paramIndex = paramCounter++;
+                if( paramIndex < paramLayoutCount )
+                {
+                    auto paramLayout = entryPointLayout->fields[paramIndex];
+                    context->builder->addLayoutDecoration(
+                        pp,
+                        paramLayout);
+                }
+                else
+                {
+                    SLANG_UNEXPECTED("too many parameters");
+                }
+            }
+        }
+
         return clonedFunc;
     }
 
diff --git a/source/slang/slang.cpp b/source/slang/slang.cpp
index dff322c29..da7601d41 100644
--- a/source/slang/slang.cpp
+++ b/source/slang/slang.cpp
@@ -918,6 +918,7 @@ SLANG_API int spCompile(
     catch (...)
     {
         req->mSink.diagnose(Slang::SourceLoc(), Slang::Diagnostics::compilationAborted);
+        req->mDiagnosticOutput = req->mSink.outputBuffer.ProduceString();
         return 1;
     }
 #else