[llvm] [offload] add support for aligned allocations (PR #203353)

[Piotr Balcer via llvm-commits]

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@@ -600,20 +615,44 @@ struct CUDADeviceTy : public GenericDeviceTy {
     switch (Kind) {
     case TARGET_ALLOC_DEFAULT:
     case TARGET_ALLOC_DEVICE:
+      if (Alignment > 0 && Alignment > Granularity) {
+        return Plugin::error(
+            ErrorCode::UNSUPPORTED,
+            "too large alignment size for the device allocation");
+      }
+
       Res = cuMemAlloc(&DevicePtr, Size);
       MemAlloc = (void *)DevicePtr;
       break;
     case TARGET_ALLOC_HOST:
+      if (Alignment > 0 && Alignment > Granularity) {
+        return Plugin::error(
+            ErrorCode::UNSUPPORTED,
+            "too large alignment size for the host allocation");
+      }
+
       Res = cuMemAllocHost(&MemAlloc, Size);
       break;
     case TARGET_ALLOC_SHARED:
+      if (Alignment > 0 && Alignment > Granularity) {
+        return Plugin::error(
+            ErrorCode::UNSUPPORTED,
+            "too large alignment size for the shared allocation");
+      }
+
       Res = cuMemAllocManaged(&DevicePtr, Size, CU_MEM_ATTACH_GLOBAL);
       MemAlloc = (void *)DevicePtr;
       break;
     }
 
     if (auto Err = Plugin::check(Res, "error in cuMemAlloc[Host|Managed]: %s"))
       return std::move(Err);
+
+    if (Alignment > 0 && !isAddrAligned(Align(Alignment), MemAlloc)) {
+      return Plugin::error(ErrorCode::UNSUPPORTED,
+                           "unsupported alignment size");
----------------
pbalcer wrote:

ditto, this will leak MemAlloc.

https://github.com/llvm/llvm-project/pull/203353