Propagate storage class attribute from SPIRV to DWARF

Storage class attribute indicates address space being pointed to. This
attribute is present in SPIRV binary. The change adds implementation to
lower this attribute to llvm IR and then later propagate it to DWARF.

Author: pratikashar

IGC/AdaptorOCL/SPIRV/SPIRVReader.cpp

@@ -520,19 +520,20 @@ class SPIRVToLLVMDbgTran {
       OpDebugPtrType ptrType(inst);
 
       auto pointeeType = createType(BM->get<SPIRVExtInst>(ptrType.getBaseType()));
+      auto storageClass = ptrType.getStorageClass();
       auto flags = ptrType.getFlags();
 
       if (flags & SPIRVDebug::Flag::FlagIsLValueReference)
-          return addMDNode(inst, Builder.createReferenceType(dwarf::DW_TAG_reference_type, pointeeType, M->getDataLayout().getPointerSizeInBits()));
+          return addMDNode(inst, Builder.createReferenceType(dwarf::DW_TAG_reference_type, pointeeType, M->getDataLayout().getPointerSizeInBits(), 0, storageClass));
       else if (flags & SPIRVDebug::Flag::FlagIsRValueReference)
-          return addMDNode(inst, Builder.createReferenceType(dwarf::DW_TAG_rvalue_reference_type, pointeeType, M->getDataLayout().getPointerSizeInBits()));
+          return addMDNode(inst, Builder.createReferenceType(dwarf::DW_TAG_rvalue_reference_type, pointeeType, M->getDataLayout().getPointerSizeInBits(), 0, storageClass));
       else if (flags & SPIRVDebug::Flag::FlagIsObjectPointer)
       {
-          auto objType = Builder.createPointerType(pointeeType, M->getDataLayout().getPointerSizeInBits());
+          auto objType = Builder.createPointerType(pointeeType, M->getDataLayout().getPointerSizeInBits(), 0, storageClass);
           return addMDNode(inst, Builder.createObjectPointerType(objType));
       }
       else
-          return addMDNode(inst, Builder.createPointerType(pointeeType, M->getDataLayout().getPointerSizeInBits()));
+          return addMDNode(inst, Builder.createPointerType(pointeeType, M->getDataLayout().getPointerSizeInBits(),0,storageClass));
   }
 
   DIType* createTypeQualifier(SPIRVExtInst* inst)

IGC/DebugInfo/DwarfCompileUnit.cpp

@@ -1760,6 +1760,13 @@ void CompileUnit::constructTypeDIE(DIE &Buffer, DIDerivedType *DTy) {
   // Add source line info if available and TyDesc is not a forward declaration.
   if (!DTy->isForwardDecl())
     addSourceLine(&Buffer, DTy);
+
+  // As per SPIRV spec, storage class value 4 corresponds to WG.
+  // We lower this value verbatim in SPIRV translator.
+  // So if dwarf address space = 4, mark it as SLM.
+  if (operator==(DTy->getDWARFAddressSpace(), 4u)) {
+    addUInt(&Buffer, dwarf::DW_AT_address_class, None, 1);
+  }
 }
 
 /// Return true if the type is appropriately scoped to be contained inside