[SYCL][Graph] Implement dynamic command-groups

sycl/doc/design/CommandGraph.md

@@ -282,6 +282,29 @@ requirements for these new accessors to correctly trigger allocations before
 updating. This is similar to how individual graph commands are enqueued when
 accessors are used in a graph node.
 
+### Dynamic Command-Group
+
+To implement the `dynamic_command_group` class for updating the command-groups (CG)
+associated with nodes, the CG member of the node implementation class changes
+from a `std::unique_ptr` to a `std::shared_ptr` so that multiple nodes and the
+`dynamic_command_group_impl` object can share the same CG object. This avoids
+the overhead of having to allocate and free copies of the CG when a new active
+CG is selected.
+
+The `dynamic_command_group_impl` class contains a list of weak pointers to the
+nodes which have been created with it, so that when a new active CG is selected
+it can propagate the change to those nodes. The `dynamic_parameter_impl` class
+also contains a list of weak pointers, but to the `dynamic_command_group_impl`
+instances of any dynamic command-groups where they are used. This allows
+updating the dynamic parameter to propagate to dynamic command-group nodes.
+
+The `sycl::detail::CGExecKernel` class has been added to, so that if the
+object was created from an element in the dynamic command-group list, the class
+stores a vector of weak pointers to the other alternative command-groups created
+from the same dynamic command-group object. This allows the SYCL runtime to
+access the list of alternative kernels when calling the UR API to append a
+kernel command to a command-buffer.
+
 ## Optimizations
 ### Interactions with Profiling
 

sycl/include/sycl/ext/oneapi/experimental/graph.hpp

@@ -96,6 +96,7 @@ class node_impl;
 class graph_impl;
 class exec_graph_impl;
 class dynamic_parameter_impl;
+class dynamic_command_group_impl;
 } // namespace detail
 
 enum class node_type {
@@ -216,6 +217,23 @@ class depends_on_all_leaves : public ::sycl::detail::DataLessProperty<
 } // namespace node
 } // namespace property
 
+class __SYCL_EXPORT dynamic_command_group {
+public:
+  dynamic_command_group(
+      const command_graph<graph_state::modifiable> &Graph,
+      const std::vector<std::function<void(handler &)>> &CGFList);
+
+  size_t get_active_cgf() const;
+  void set_active_cgf(size_t Index);
+
+private:
+  template <class Obj>
+  friend const decltype(Obj::impl) &
+  sycl::detail::getSyclObjImpl(const Obj &SyclObject);
+
+  std::shared_ptr<detail::dynamic_command_group_impl> impl;
+};
+
 namespace detail {
 // Templateless modifiable command-graph base class.
 class __SYCL_EXPORT modifiable_command_graph {
@@ -337,6 +355,12 @@ class __SYCL_EXPORT modifiable_command_graph {
   modifiable_command_graph(const std::shared_ptr<detail::graph_impl> &Impl)
       : impl(Impl) {}
 
+  /// Template-less implementation of add() for dynamic command-group nodes.
+  /// @param DynCGF Dynamic Command-group function object to add.
+  /// @param Dep List of predecessor nodes.
+  /// @return Node added to the graph.
+  node addImpl(dynamic_command_group &DynCGF, const std::vector<node> &Dep);
+
   /// Template-less implementation of add() for CGF nodes.
   /// @param CGF Command-group function to add.
   /// @param Dep List of predecessor nodes.

sycl/include/sycl/handler.hpp

@@ -1175,7 +1175,6 @@ class __SYCL_EXPORT handler {
       StoreLambda<KName, decltype(Wrapper), Dims, TransformedArgType>(
           std::move(Wrapper));
       setType(detail::CGType::Kernel);
-      setNDRangeUsed(false);
 #endif
     } else
 #endif // !__SYCL_DISABLE_PARALLEL_FOR_RANGE_ROUNDING__ &&
@@ -1198,7 +1197,6 @@ class __SYCL_EXPORT handler {
       StoreLambda<NameT, KernelType, Dims, TransformedArgType>(
           std::move(KernelFunc));
       setType(detail::CGType::Kernel);
-      setNDRangeUsed(false);
 #endif
 #else
       (void)KernelFunc;
@@ -1249,7 +1247,6 @@ class __SYCL_EXPORT handler {
     StoreLambda<NameT, KernelType, Dims, TransformedArgType>(
         std::move(KernelFunc));
     setType(detail::CGType::Kernel);
-    setNDRangeUsed(true);
 #endif
   }
 
@@ -1272,7 +1269,6 @@ class __SYCL_EXPORT handler {
     setNDRangeDescriptor(std::move(NumWorkItems));
     processLaunchProperties<PropertiesT>(Props);
     setType(detail::CGType::Kernel);
-    setNDRangeUsed(false);
     extractArgsAndReqs();
     MKernelName = getKernelName();
 #endif
@@ -1298,7 +1294,6 @@ class __SYCL_EXPORT handler {
     setNDRangeDescriptor(std::move(NDRange));
     processLaunchProperties(Props);
     setType(detail::CGType::Kernel);
-    setNDRangeUsed(true);
     extractArgsAndReqs();
     MKernelName = getKernelName();
 #endif
@@ -1339,7 +1334,6 @@ class __SYCL_EXPORT handler {
     setNDRangeDescriptor(NumWorkGroups, /*SetNumWorkGroups=*/true);
     StoreLambda<NameT, KernelType, Dims, LambdaArgType>(std::move(KernelFunc));
     setType(detail::CGType::Kernel);
-    setNDRangeUsed(false);
 #endif // __SYCL_DEVICE_ONLY__
   }
 
@@ -1971,7 +1965,6 @@ class __SYCL_EXPORT handler {
     StoreLambda<NameT, KernelType, Dims, TransformedArgType>(
         std::move(KernelFunc));
     setType(detail::CGType::Kernel);
-    setNDRangeUsed(false);
 #endif
   }
 
@@ -2069,7 +2062,6 @@ class __SYCL_EXPORT handler {
     detail::checkValueRange<Dims>(NumWorkItems, WorkItemOffset);
     setNDRangeDescriptor(std::move(NumWorkItems), std::move(WorkItemOffset));
     setType(detail::CGType::Kernel);
-    setNDRangeUsed(false);
     extractArgsAndReqs();
     MKernelName = getKernelName();
 #endif
@@ -2148,7 +2140,6 @@ class __SYCL_EXPORT handler {
     setNDRangeDescriptor(std::move(NumWorkItems));
     MKernel = detail::getSyclObjImpl(std::move(Kernel));
     setType(detail::CGType::Kernel);
-    setNDRangeUsed(false);
     if (!lambdaAndKernelHaveEqualName<NameT>()) {
       extractArgsAndReqs();
       MKernelName = getKernelName();
@@ -2189,7 +2180,6 @@ class __SYCL_EXPORT handler {
     setNDRangeDescriptor(std::move(NumWorkItems), std::move(WorkItemOffset));
     MKernel = detail::getSyclObjImpl(std::move(Kernel));
     setType(detail::CGType::Kernel);
-    setNDRangeUsed(false);
     if (!lambdaAndKernelHaveEqualName<NameT>()) {
       extractArgsAndReqs();
       MKernelName = getKernelName();
@@ -2229,7 +2219,6 @@ class __SYCL_EXPORT handler {
     setNDRangeDescriptor(std::move(NDRange));
     MKernel = detail::getSyclObjImpl(std::move(Kernel));
     setType(detail::CGType::Kernel);
-    setNDRangeUsed(true);
     if (!lambdaAndKernelHaveEqualName<NameT>()) {
       extractArgsAndReqs();
       MKernelName = getKernelName();
@@ -3357,6 +3346,7 @@ class __SYCL_EXPORT handler {
                                  size_t Size, bool Block = false);
   friend class ext::oneapi::experimental::detail::graph_impl;
   friend class ext::oneapi::experimental::detail::dynamic_parameter_impl;
+  friend class ext::oneapi::experimental::detail::dynamic_command_group_impl;
 
   bool DisableRangeRounding();
 
@@ -3626,8 +3616,10 @@ class __SYCL_EXPORT handler {
   }
 #endif
 
+#ifndef __INTEL_PREVIEW_BREAKING_CHANGES
   // Set that an ND Range was used during a call to parallel_for
   void setNDRangeUsed(bool Value);
+#endif
 
   inline void internalProfilingTagImpl() {
     throwIfActionIsCreated();

sycl/source/detail/cg.hpp

@@ -257,6 +257,9 @@ class CGExecKernel : public CG {
   std::string MKernelName;
   std::vector<std::shared_ptr<detail::stream_impl>> MStreams;
   std::vector<std::shared_ptr<const void>> MAuxiliaryResources;
+  /// Used to implement ext_oneapi_graph dynamic_command_group. Stores the list
+  /// of command-groups that a kernel command can be updated to.
+  std::vector<std::weak_ptr<CGExecKernel>> MAlternativeKernels;
   ur_kernel_cache_config_t MKernelCacheConfig;
   bool MKernelIsCooperative = false;
   bool MKernelUsesClusterLaunch = false;
@@ -277,7 +280,7 @@ class CGExecKernel : public CG {
         MKernelBundle(std::move(KernelBundle)), MArgs(std::move(Args)),
         MKernelName(std::move(KernelName)), MStreams(std::move(Streams)),
         MAuxiliaryResources(std::move(AuxiliaryResources)),
-        MKernelCacheConfig(std::move(KernelCacheConfig)),
+        MAlternativeKernels{}, MKernelCacheConfig(std::move(KernelCacheConfig)),
         MKernelIsCooperative(KernelIsCooperative),
         MKernelUsesClusterLaunch(MKernelUsesClusterLaunch) {
     assert(getType() == CGType::Kernel && "Wrong type of exec kernel CG.");