Fix hit object emit for HLSL + FuncType specialization bug fix. (#2976)

* Fix hit object emit for HLSL.

* Fix a bug involving specialization of functon type.

* Add a test case.

---------

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

6 files changed, 50 insertions, 9 deletions

diff --git a/source/slang/slang-emit-hlsl.cpp b/source/slang/slang-emit-hlsl.cpp
index 76300c18b..bc6b7a159 100644
--- a/source/slang/slang-emit-hlsl.cpp
+++ b/source/slang/slang-emit-hlsl.cpp
@@ -926,7 +926,7 @@ void HLSLSourceEmitter::emitSimpleTypeImpl(IRType* type)
         }
         case kIROp_HitObjectType:
         {
-            m_writer->emit("HitObject");
+            m_writer->emit("NvHitObject");
             return;
         }
         default: break;
diff --git a/source/slang/slang-ir-link.cpp b/source/slang/slang-ir-link.cpp
index 14e79560e..f57919e44 100644
--- a/source/slang/slang-ir-link.cpp
+++ b/source/slang/slang-ir-link.cpp
@@ -1198,10 +1198,11 @@ IRInst* cloneInst(
         IRInst* clonedArg = cloneValue(context, originalArg);
         newArgs[aa] = clonedArg;
     }
+    auto funcType = cloneType(context, originalInst->getFullType());
     context->builder = oldBuilder;
 
     IRInst* clonedInst = builder->createIntrinsicInst(
-        cloneType(context, originalInst->getFullType()),
+        funcType,
         originalInst->getOp(),
         argCount, newArgs.getArrayView().getBuffer());
     builder->addInst(clonedInst);
diff --git a/source/slang/slang-ir-lower-witness-lookup.cpp b/source/slang/slang-ir-lower-witness-lookup.cpp
index 841617ac8..b94059238 100644
--- a/source/slang/slang-ir-lower-witness-lookup.cpp
+++ b/source/slang/slang-ir-lower-witness-lookup.cpp
@@ -106,7 +106,7 @@ struct WitnessLookupLoweringContext
                     translatedOperands.add(translateType(builder, type->getOperand(i)));
                 }
                 auto translated = builder.emitIntrinsicInst(
-                    builder.getTypeKind(),
+                    type->getFullType(),
                     type->getOp(),
                     (UInt)translatedOperands.getCount(),
                     translatedOperands.getBuffer());
diff --git a/source/slang/slang-ir.cpp b/source/slang/slang-ir.cpp
index 74679de96..84730c913 100644
--- a/source/slang/slang-ir.cpp
+++ b/source/slang/slang-ir.cpp
@@ -1570,6 +1570,10 @@ namespace Slang
 
             parent = mergeCandidateParentsForHoistableInst(parent, operandParent);
         }
+        if (inst->getFullType())
+        {
+            parent = mergeCandidateParentsForHoistableInst(parent, inst->getFullType()->getParent());
+        }
 
         // We better have ended up with a parent to insert into,
         // or else the invariants of our IR have been violated.
diff --git a/source/slang/slang-lower-to-ir.cpp b/source/slang/slang-lower-to-ir.cpp
index cf564605c..7b649ff0d 100644
--- a/source/slang/slang-lower-to-ir.cpp
+++ b/source/slang/slang-lower-to-ir.cpp
@@ -8577,6 +8577,12 @@ struct DeclLoweringVisitor : DeclVisitor<DeclLoweringVisitor, LoweredValInfo>
         else
             outerGeneric = emitOuterGenerics(subContext, decl, decl);
 
+        FuncDeclBaseTypeInfo info;
+        _lowerFuncDeclBaseTypeInfo(
+            subContext,
+            createDefaultSpecializedDeclRef(context, nullptr, decl),
+            info);
+
         // need to create an IR function here
 
         IRFunc* irFunc = subBuilder->createFunc();
@@ -8598,12 +8604,6 @@ struct DeclLoweringVisitor : DeclVisitor<DeclLoweringVisitor, LoweredValInfo>
             }
         }
 
-        FuncDeclBaseTypeInfo info;
-        _lowerFuncDeclBaseTypeInfo(
-            subContext,
-            createDefaultSpecializedDeclRef(context, nullptr, decl),
-            info);
-
         auto irFuncType = info.type;
         auto& irResultType = info.resultType;
         auto& parameterLists = info.parameterLists;
diff --git a/tests/bugs/func-type-specialize.slang b/tests/bugs/func-type-specialize.slang
new file mode 100644
index 000000000..7e17c5c3d
--- /dev/null
+++ b/tests/bugs/func-type-specialize.slang
@@ -0,0 +1,36 @@
+//TEST:SIMPLE(filecheck=CHECK):-target hlsl -entry computeMain -profile cs_6_5 -validate-ir
+//TEST_INPUT:ubuffer(data=[0 0 0], stride=4):out,name=outputBuffer
+RWStructuredBuffer<float> outputBuffer;
+
+// CHECK: void computeMain
+// CHECK: RayQuery<0
+interface IFoo
+{
+    int doThing<let f : int>(RayQuery<f> arr);
+}
+
+
+struct HitInfo
+{
+    static int makeHitInfo<let f : int>(RayQuery<f> q)
+    {
+        return 0;
+    }
+}
+
+struct Impl : IFoo
+{
+    int doThing<let f : int>(RayQuery<f> arr)
+    {
+        return HitInfo.makeHitInfo(arr);
+    }
+}
+
+RWStructuredBuffer<int> outVal;
+[numthreads(1, 1, 1)]
+void computeMain(uint3 dispatchThreadID: SV_DispatchThreadID)
+{
+    Impl impl;
+    RayQuery<0> q;
+    outVal[dispatchThreadID.x] = impl.doThing(q);
+}
\ No newline at end of file