Fix out of bound enum conversion (#13967)

This PR fixes Wenum-constexpr-conversion which is introduced in recent version of clang.
Explciitly use integer instead of enum to store the device that may contain invalid options.

Author: tqchen

include/tvm/runtime/ndarray.h

@@ -42,14 +42,6 @@ namespace tvm {
 // alias DLDevice
 using Device = DLDevice;
 
-// A 'null' device type, does not correspond to any DLDeviceType enum.
-// TODO(mbs): This is to help us as we transition away from representing the 'homogenous' case
-// as a singleton target map indexed by the invalid DLDeviceType '0'.
-constexpr DLDeviceType kNullDeviceType = static_cast<DLDeviceType>(0);
-
-// An 'invalid' device type, does not correspond to any DLDeviceType enum.
-constexpr DLDeviceType kInvalidDeviceType = static_cast<DLDeviceType>(-1);
-
 namespace runtime {
 
 /*!

include/tvm/target/virtual_device.h

@@ -44,6 +44,16 @@ namespace tvm {
  */
 using MemoryScope = String;
 
+// NOTE: cannot use enum as they are out of bound of the original enum
+// and results in an undefined behavior
+// A 'null' device type, does not correspond to any DLDeviceType enum.
+// TODO(mbs): This is to help us as we transition away from representing the 'homogenous' case
+// as a singleton target map indexed by the invalid DLDeviceType '0'.
+constexpr int kNullDeviceType = 0;
+
+// An 'invalid' device type, does not correspond to any DLDeviceType enum.
+constexpr int kInvalidDeviceType = -1;
+
 /*!
  * \brief Describes at compile time the constraints on where data is to be stored at runtime
  * down to the (virtual) device and memory scope level, and how to compile code to compute that
@@ -229,7 +239,7 @@ class VirtualDeviceNode : public AttrsNode<VirtualDeviceNode> {
    * Physical Devices" above.
    */
   Device ToDevice() const {
-    ICHECK(device_type() != kInvalidDeviceType);
+    ICHECK(device_type_int != kInvalidDeviceType);
     ICHECK(virtual_device_id != -1);
     Device device;
     device.device_type = device_type();
@@ -262,7 +272,7 @@ class VirtualDevice : public ObjectRef {
  public:
   /*!
    * \brief Construct a virtual device.
-   * \param device_type The device type for the virtual device, or \p kInvalidDeviceType if
+   * \param device_type_int The device type for the virtual device, or \p kInvalidDeviceType if
    * unconstrained.  If \p target is defined then must match its \p target->GetTargetDeviceType().
    * \param virtual_device_id The device id for the virtual device, or -1 if unconstrained.
    * \param target The target describing how to compile for the virtual device, or null if
@@ -271,7 +281,7 @@ class VirtualDevice : public ObjectRef {
    * unconstrained.
    * \return The virtual device.
    */
-  explicit VirtualDevice(DLDeviceType device_type = kInvalidDeviceType, int virtual_device_id = -1,
+  explicit VirtualDevice(int device_type_int = kInvalidDeviceType, int virtual_device_id = -1,
                          Target target = {}, MemoryScope memory_scope = {});
 
   /*! \brief Returns the unique fully unconstrained \p VirtualDevice. */
@@ -349,7 +359,7 @@ class VirtualDevice : public ObjectRef {
 class VirtualDeviceCache {
  public:
   /*! \brief Returns the unique \p VirtualDevice representing given fields. */
-  VirtualDevice Make(DLDeviceType device_type = kInvalidDeviceType, int virtual_device_id = -1,
+  VirtualDevice Make(int device_type = kInvalidDeviceType, int virtual_device_id = -1,
                      Target target = {}, MemoryScope memory_scope = {});
 
   /*!

src/target/virtual_device.cc

@@ -66,13 +66,13 @@ TVM_STATIC_IR_FUNCTOR(ReprPrinter, vtable)
       p->stream << ")";
     });
 
-VirtualDevice::VirtualDevice(DLDeviceType device_type, int virtual_device_id, Target target,
+VirtualDevice::VirtualDevice(int device_type_int, int virtual_device_id, Target target,
                              MemoryScope memory_scope) {
-  ICHECK(!target.defined() || device_type == target->GetTargetDeviceType())
+  ICHECK(!target.defined() || device_type_int == target->GetTargetDeviceType())
       << "target " << target->ToDebugString() << " has device type "
-      << target->GetTargetDeviceType() << " but virtual device has device type " << device_type;
+      << target->GetTargetDeviceType() << " but virtual device has device type " << device_type_int;
   auto node = make_object<VirtualDeviceNode>();
-  node->device_type_int = device_type;
+  node->device_type_int = device_type_int;
   node->virtual_device_id = virtual_device_id;
   node->target = std::move(target);
   node->memory_scope = std::move(memory_scope);
@@ -166,8 +166,8 @@ VirtualDevice VirtualDevice::Default(const VirtualDevice& lhs, const VirtualDevi
                        defaulted_memory_scope);
 }
 
-VirtualDevice VirtualDeviceCache::Make(DLDeviceType device_type, int virtual_device_id,
-                                       Target target, MemoryScope memory_scope) {
+VirtualDevice VirtualDeviceCache::Make(int device_type, int virtual_device_id, Target target,
+                                       MemoryScope memory_scope) {
   VirtualDevice prototype(device_type, virtual_device_id, std::move(target),
                           std::move(memory_scope));
   if (prototype->IsFullyUnconstrained()) {