Add unbounded array support by modifying LLVM IR -> SPIRV type lowering

Author: lbushi25

clang/lib/CodeGen/CodeGenTypes.cpp

@@ -807,8 +807,9 @@ llvm::Type *CodeGenTypes::ConvertType(QualType T) {
     if (!ResultType->isSized()) {
       SkippedLayout = true;
       ResultType = llvm::Type::getInt8Ty(getLLVMContext());
-    } 
-    ResultType = llvm::ArrayType::get(ResultType, Context.getLangOpts().SYCLIsDevice ? 1 : 0);
+    }
+    ResultType = llvm::ArrayType::get(
+        ResultType, 0);
     break;
   }
   case Type::ArrayParameter:

llvm-spirv/lib/SPIRV/SPIRVWriter.cpp

@@ -453,24 +453,19 @@ SPIRVType *LLVMToSPIRVBase::transType(Type *T) {
   if (T->isArrayTy()) {
     // SPIR-V 1.3 s3.32.6: Length is the number of elements in the array.
     //                     It must be at least 1.
-    if (T->getArrayNumElements() < 1) {
-      std::string Str;
-      llvm::raw_string_ostream OS(Str);
-      OS << *T;
-      SPIRVCK(T->getArrayNumElements() >= 1, InvalidArraySize, OS.str());
-    }
+    const auto ArraySize = T->getArrayNumElements() ? T->getArrayNumElements() : 1;
     Type *ElTy = T->getArrayElementType();
     SPIRVType *TransType = BM->addArrayType(
         transType(ElTy),
         static_cast<SPIRVConstant *>(transValue(
-            ConstantInt::get(getSizetType(), T->getArrayNumElements(), false),
+            ConstantInt::get(getSizetType(), ArraySize, false),
             nullptr)));
     mapType(T, TransType);
     if (ElTy->isPointerTy()) {
       mapType(
           ArrayType::get(TypedPointerType::get(Type::getInt8Ty(*Ctx),
                                                ElTy->getPointerAddressSpace()),
-                         T->getArrayNumElements()),
+                         ArraySize),
           TransType);
     }
     return TransType;