1 files changed, 101 insertions, 0 deletions
diff --git a/source/slang/slang-ir-generics-lowering-context.cpp b/source/slang/slang-ir-generics-lowering-context.cpp
new file mode 100644
index 000000000..6ee0a17f0
--- /dev/null
+++ b/source/slang/slang-ir-generics-lowering-context.cpp
@@ -0,0 +1,101 @@
+//slang-ir-generics-lowering-context.cpp
+
+#include "slang-ir-generics-lowering-context.h"
+
+#include "slang-ir-layout.h"
+
+namespace Slang
+{
+    bool isPolymorphicType(IRInst* typeInst)
+    {
+        if (as<IRParam>(typeInst) && as<IRTypeType>(typeInst->getDataType()))
+            return true;
+        switch (typeInst->op)
+        {
+        case kIROp_ThisType:
+        case kIROp_AssociatedType:
+        case kIROp_InterfaceType:
+            return true;
+        case kIROp_Specialize:
+        {
+            for (UInt i = 0; i < typeInst->getOperandCount(); i++)
+            {
+                if (isPolymorphicType(typeInst->getOperand(i)))
+                    return true;
+            }
+            return false;
+        }
+        default:
+            break;
+        }
+        if (auto ptrType = as<IRPtrTypeBase>(typeInst))
+        {
+            return isPolymorphicType(ptrType->getValueType());
+        }
+        return false;
+    }
+
+    bool isTypeValue(IRInst* typeInst)
+    {
+        if (typeInst)
+        {
+            switch (typeInst->op)
+            {
+            case kIROp_TypeType:
+                return true;
+            case kIROp_lookup_interface_method:
+                return typeInst->getDataType()->op == kIROp_TypeKind;
+            default:
+                return false;
+            }
+        }
+        return false;
+    }
+
+    IRInst* SharedGenericsLoweringContext::maybeEmitRTTIObject(IRInst* typeInst)
+    {
+        IRInst* result = nullptr;
+        if (mapTypeToRTTIObject.TryGetValue(typeInst, result))
+            return result;
+        IRBuilder builderStorage;
+        auto builder = &builderStorage;
+        builder->sharedBuilder = &sharedBuilderStorage;
+        builder->setInsertBefore(typeInst->next);
+
+        result = builder->emitMakeRTTIObject(typeInst);
+
+        // For now the only type info we encapsualte is type size.
+        IRSizeAndAlignment sizeAndAlignment;
+        getNaturalSizeAndAlignment((IRType*)typeInst, &sizeAndAlignment);
+        builder->addRTTITypeSizeDecoration(result, sizeAndAlignment.size);
+
+        // Give a name to the rtti object.
+        if (auto exportDecoration = typeInst->findDecoration<IRExportDecoration>())
+        {
+            String rttiObjName = String(exportDecoration->getMangledName()) + "_rtti";
+            builder->addExportDecoration(result, rttiObjName.getUnownedSlice());
+        }
+        mapTypeToRTTIObject[typeInst] = result;
+        return result;
+    }
+
+    IRInst* SharedGenericsLoweringContext::findInterfaceRequirementVal(IRInterfaceType* interfaceType, IRInst* requirementKey)
+    {
+        if (auto dict = mapInterfaceRequirementKeyValue.TryGetValue(interfaceType))
+            return (*dict)[requirementKey].GetValue();
+        _builldInterfaceRequirementMap(interfaceType);
+        return findInterfaceRequirementVal(interfaceType, requirementKey);
+    }
+
+    void SharedGenericsLoweringContext::_builldInterfaceRequirementMap(IRInterfaceType* interfaceType)
+    {
+        mapInterfaceRequirementKeyValue.Add(interfaceType,
+            Dictionary<IRInst*, IRInst*>());
+        auto dict = mapInterfaceRequirementKeyValue.TryGetValue(interfaceType);
+        for (UInt i = 0; i < interfaceType->getOperandCount(); i++)
+        {
+            auto entry = cast<IRInterfaceRequirementEntry>(interfaceType->getOperand(i));
+            (*dict)[entry->getRequirementKey()] = entry->getRequirementVal();
+        }
+    }
+}