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

[Johannes Doerfert via llvm-commits]

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@@ -0,0 +1,325 @@
+//===-------- SplitModuleByCategory.cpp - split a module by categories ----===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// See comments in the header.
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Utils/SplitModuleByCategory.h"
+#include "llvm/ADT/SetVector.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/InstIterator.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Transforms/Utils/Cloning.h"
+
+#include <map>
+#include <string>
+#include <utility>
+
+using namespace llvm;
+
+#define DEBUG_TYPE "split-module-by-category"
+
+namespace {
+
+// A vector that contains a group of function with the same category.
+using EntryPointSet = SetVector<const Function *>;
+
+/// Represents a group of functions with one category.
+struct EntryPointGroup {
+  int ID;
+  EntryPointSet Functions;
+
+  EntryPointGroup() = default;
+
+  EntryPointGroup(int ID, EntryPointSet Functions = EntryPointSet())
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jdoerfert wrote:

Doesn't this copy the set first before you move it below?

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