[llvm] [offload] Fix minor memory manager alignment bugs (PR #223979)

[Łukasz Plewa via llvm-commits]

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@@ -260,7 +261,14 @@ class MemoryManagerTy {
     if (Size == 0)
       return nullptr;
 
-    size_t AllocationSize = Alignment > 0 ? (Size + Alignment - 1) : Size;
+    if (Alignment > 0 &&
+        Size > std::numeric_limits<size_t>::max() - (Alignment - 1)) {
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lplewa wrote:

NIT: for sure there is helper for it in llvm

https://github.com/llvm/llvm-project/pull/223979