[llvm] [offload][SYCL] Add Module splitting by categories. (PR #131347)

[Arvind Sudarsanam via llvm-commits]

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@@ -22,21 +22,23 @@ namespace llvm {
 class Module;
 class Function;
 
-namespace sycl {
-
-/// FunctionCategorizer returns integer category for the given Function.
-/// Otherwise, it returns std::nullopt if function doesn't have a category.
-using FunctionCategorizer = function_ref<std::optional<int>(const Function &F)>;
-
-using PostSplitCallbackType = function_ref<void(std::unique_ptr<Module> Part)>;
-
-/// Splits the given module \p M.
-/// Every split image is being passed to \p Callback for further possible
+/// Splits the given module \p M using the given \p FunctionCategorizer.
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asudarsa wrote:

Sorry. But it is still not clear what a function category means here and what are some examples of it.

https://github.com/llvm/llvm-project/pull/131347