Restore types of byval kernel arguments

Before introduction of full  opaque pointers support in situations when
the frontend uses opaque pointers, but the backend still uses typed the
information about original kernel arguments pointer element types was
lost by spirv-translator and i8* was used instead. This is critical for
byval arguments, so these types must be restored using information from
genx.convert intrinsics.

Author: mshelego

GenXIntrinsics/lib/GenXIntrinsics/GenXSPIRVReaderAdaptor.cpp

@@ -481,6 +481,10 @@ transformKernelSignature(Function &F, const std::vector<SPIRVArgDesc> &Descs) {
                        return PointerType::get(Type::getInt8Ty(Ctx), AddrSpace);
                      }
 #endif
+                     if (!VCINTR::Type::isOpaquePointerTy(ArgTy) &&
+                         Arg.hasByValAttr())
+                       return OrigTy;
+
                      return ArgTy;
                    }
                    if (OrigTy->isPointerTy() && ArgTy->isPointerTy())

GenXIntrinsics/test/Adaptors/args_attributes_transform_reader.ll

@@ -20,4 +20,14 @@ define spir_kernel void @test(%foo addrspace(1)* byval(%foo) %arg) #0 {
   ret void
 }
 
+; CHECK: define dllexport spir_kernel void @test_restore(
+; CHECK-SAME: %foo* byval(%foo)
+; CHECK-SAME: [[ARG:%[^)]+]])
+define spir_kernel void @test_restore(i8 addrspace(1)* byval(i8) %arg) #0 {
+  %conv = call %foo* @llvm.genx.address.convert.p0foo.p1i8(i8 addrspace(1)* %arg)
+  ret void
+}
+
+declare %foo* @llvm.genx.address.convert.p0foo.p1i8(i8 addrspace(1)*) #0
+
 attributes #0 = { "VCFunction" }