[DLPack][runtime] Update DLPack to v0.7

- Update the `3rdparty/dlpack` git submodule from v0.5 to v0.7, so that
the `DLDeviceType` enumeration has an explicitly-stated underlying
storage type.  This addresses a compiler warning generated by clang
15.0.3.

- Remove `kDLHexagon` and `kDLWebGPU` from `TVMDeviceExtType`, because
those enumerators are now provided by `DLDeviceType`.

- Renumber the members of `TVMDeviceExtType` to reduce the chance of
unnoticed collision with members of `DLDeviceType`.

include/tvm/runtime/c_runtime_api.h

@@ -80,14 +80,40 @@ extern "C" {
 /*! \brief type of array index. */
 typedef int64_t tvm_index_t;
 
-/*! \brief Extension device types in TVM */
+/*! \brief Extension device types in TVM
+ *
+ * An extended version of DLPack's `DLDeviceType` enumeration.
+ *
+ * These enumerators are a supsetset of those provided by
+ * `DLDeviceType`.
+ *
+ * MAINTAINERS NOTE #1: We need to ensure that these two
+ * enumerations don't use conflicting symbols for the same
+ * integer.  Currently this requires manual verification.
+ * Discussed here: https://github.com/dmlc/dlpack/issues/111
+ * As of DLPack v0.7, the highest-valued enumerator in
+ * `DLDeviceType` is kDLHexagon = 16.
+ *
+ * MAINTAINERS NOTE #2: It's important that when C/C++ compilers
+ * choose the underlying storage type for `DLDeviceType` and
+ * `TVMDeviceExtType`, the underlying type can store whatever
+ * integer values appear in *either* enumeration.
+ * For C++, we enforce this by specifying `int32_t` for both
+ * enumerations.  For C, this is currently unenforced, and
+ * may be a latent bug.
+ */
+#ifdef __cplusplus
+typedef enum : int32_t {
+#else
 typedef enum {
-  kDLAOCL = 5,
-  kDLSDAccel = 6,
-  kOpenGL = 11,
-  kDLMicroDev = 13,
-  kDLHexagon = 14,
-  kDLWebGPU = 15
+#endif
+  // To help avoid accidental conflicts between `DLDeviceType`
+  // and this enumeration, start numbering the new enumerators
+  // a little higher than (currently) seems necessary.
+  kDLAOCL = kDLHexagon + 10,
+  kDLSDAccel,
+  kOpenGL,
+  kDLMicroDev,
   // AddExtraTVMType which is not in DLPack here
 } TVMDeviceExtType;
 

src/runtime/aot_executor/aot_executor.cc

@@ -49,8 +49,8 @@ AotExecutor::AotExecutor(tvm::runtime::Module module, const std::vector<Device>&
   ICHECK_EQ(devices_[0].device_id, expected_device.device_id)
       << "At this time, AOTExecutor supports only execution on kDLCPU 0";
   // TODO(tvm-team): Temporary hack since Hexagon is defined different than kDLCPU.
-  bool is_valid_device = (TVMDeviceExtType(devices_[0].device_type) == kDLHexagon) ||
-                         (DLDeviceType(devices_[0].device_type) == kDLCPU);
+  bool is_valid_device =
+      (devices_[0].device_type == kDLHexagon) || (devices_[0].device_type == kDLCPU);
   CHECK(is_valid_device)
       << "At this time, AOTExecutor supports only execution on kDLCPU 0 or kDLHexagon 0";
 

src/runtime/hexagon/hexagon_common.h

@@ -45,9 +45,7 @@
     }                                                                             \
   } while (0)
 
-inline bool IsHexagonDevice(DLDevice dev) {
-  return TVMDeviceExtType(dev.device_type) == kDLHexagon;
-}
+inline bool IsHexagonDevice(DLDevice dev) { return dev.device_type == kDLHexagon; }
 
 constexpr int kHexagonAllocAlignment = 2048;
 

src/runtime/hexagon/hexagon_device_api.cc

@@ -81,7 +81,7 @@ void* HexagonDeviceAPI::AllocDataSpace(Device dev, int ndim, const int64_t* shap
 
   // NOTE: This check should be superfluous, but it's probably a good idea to leave it in
   // until the AoT executor's multi-device dispatch code is mature. --cconvey 2022-08-26
-  CHECK(TVMDeviceExtType(dev.device_type) == kDLHexagon)
+  CHECK(dev.device_type == kDLHexagon)
       << "dev.device_type: " << dev.device_type << " DeviceName(" << dev.device_type
       << "): " << DeviceName(dev.device_type) << "";
 
@@ -162,14 +162,14 @@ void HexagonDeviceAPI::FreeWorkspace(Device dev, void* data) {
 void* HexagonDeviceAPI::AllocVtcmWorkspace(Device dev, int ndim, const int64_t* shape,
                                            DLDataType dtype, Optional<String> mem_scope) {
   // must be Hexagon device (not CPU)
-  CHECK(TVMDeviceExtType(dev.device_type) == kDLHexagon) << "dev.device_type: " << dev.device_type;
+  CHECK(dev.device_type == kDLHexagon) << "dev.device_type: " << dev.device_type;
   CHECK((ndim == 1 || ndim == 2) && "Hexagon Device API supports only 1d and 2d allocations");
   return AllocDataSpace(dev, ndim, shape, dtype, mem_scope);
 }
 
 void HexagonDeviceAPI::FreeVtcmWorkspace(Device dev, void* ptr) {
   // must be Hexagon device (not CPU)
-  CHECK(TVMDeviceExtType(dev.device_type) == kDLHexagon) << "dev.device_type: " << dev.device_type;
+  CHECK(dev.device_type == kDLHexagon) << "dev.device_type: " << dev.device_type;
   FreeDataSpace(dev, ptr);
 }
 

src/runtime/hexagon/hexagon_device_api.h

@@ -189,8 +189,7 @@ class HexagonDeviceAPI final : public DeviceAPI {
    */
   bool IsValidDevice(DLDevice dev) {
     // Added kDLCPU since we use hexagon as a sub-target of LLVM which by default maps to kDLCPU
-    return (TVMDeviceExtType(dev.device_type) == kDLHexagon) ||
-           (DLDeviceType(dev.device_type) == kDLCPU);
+    return (dev.device_type == kDLHexagon) || (dev.device_type == kDLCPU);
   }
 
   //! \brief Manages runtime HexagonBuffer allocations