[SYCL][Graph] Fix bugs with HIP/CUDA UR sync points. (#14858)

Tests UR PR oneapi-src/unified-runtime#1910

Author: Ewan Crawford

sycl/cmake/modules/FetchUnifiedRuntime.cmake

@@ -117,13 +117,13 @@ if(SYCL_PI_UR_USE_FETCH_CONTENT)
   endfunction()
 
   set(UNIFIED_RUNTIME_REPO "https://github.com/oneapi-src/unified-runtime.git")
-  # commit 83f7ad9551ce0134931b44804b5a254ae2e93068
-  # Merge: ab9baf57 8fb6824d
+  # commit 3c12bbceec33cf5cf5fc4fa85e641b4f95e820b7
+  # Merge: 83f7ad95 ac7eb171
   # Author: Omar Ahmed <omar.ahmed@codeplay.com>
-  # Date:   Thu Aug 8 11:11:13 2024 +0100
-  #     Merge pull request #1860 from PietroGhg/pietro/fill
-  #     [NATIVECPU] Fix pointer arithmetic in USMfill
-  set(UNIFIED_RUNTIME_TAG 83f7ad9551ce0134931b44804b5a254ae2e93068)
+  # Date:   Fri Aug 9 10:51:05 2024 +0100
+  #     Merge pull request #1910 from Bensuo/sync_point
+  #     [CUDA][HIP] Improve command-buffer sync points
+  set(UNIFIED_RUNTIME_TAG 3c12bbceec33cf5cf5fc4fa85e641b4f95e820b7)
 
   set(UMF_BUILD_EXAMPLES OFF CACHE INTERNAL "EXAMPLES")
   # Due to the use of dependentloadflag and no installer for UMF and hwloc we need

sycl/doc/design/CommandGraph.md

@@ -480,6 +480,14 @@ An executable CUDA Graph, which contains all commands and synchronization
 information, is saved in the UR command-buffer to allow for efficient graph
 resubmission.
 
+#### Prefetch & Advise
+
+The `urCommandBufferAppendUSMPrefetchExp` and
+`urCommandBufferAppendUSMAdviseExp` UR entry-points used to implement
+`handler::prefetch` and `handler::mem_advise` are implemented in the CUDA UR
+adapter as empty nodes enforcing the node dependencies. As such the
+optimization hints are a no-op.
+
 ### HIP
 
 The HIP backend offers a graph management API very similar to CUDA Graph
@@ -502,6 +510,14 @@ An executable HIP Graph, which contains all commands and synchronization
 information, is saved in the UR command-buffer to allow for efficient
 graph resubmission.
 
+#### Prefetch & Advise
+
+The `urCommandBufferAppendUSMPrefetchExp` and
+`urCommandBufferAppendUSMAdviseExp` UR entry-points used to implement
+`handler::prefetch` and `handler::mem_advise` are implemented in the HIP UR
+adapter as empty nodes enforcing the node dependencies. As such the
+optimization hints are a no-op.
+
 ### OpenCL
 
 SYCL-Graph is only enabled for an OpenCL backend when the