xref: /freebsd/contrib/llvm-project/llvm/include/llvm/Transforms/Utils/SplitModule.h (revision 700637cbb5e582861067a11aaca4d053546871d2)
1 //===- SplitModule.h - Split a module into partitions -----------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines the function llvm::SplitModule, which splits a module
10 // into multiple linkable partitions. It can be used to implement parallel code
11 // generation for link-time optimization.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_TRANSFORMS_UTILS_SPLITMODULE_H
16 #define LLVM_TRANSFORMS_UTILS_SPLITMODULE_H
17 
18 #include "llvm/ADT/STLFunctionalExtras.h"
19 #include "llvm/Support/Compiler.h"
20 #include <memory>
21 
22 namespace llvm {
23 
24 class Module;
25 
26 /// Splits the module M into N linkable partitions. The function ModuleCallback
27 /// is called N times passing each individual partition as the MPart argument.
28 /// PreserveLocals: Split without externalizing locals.
29 /// RoundRobin: Use round-robin distribution of functions to modules instead
30 /// of the default name-hash-based one.
31 ///
32 /// FIXME: This function does not deal with the somewhat subtle symbol
33 /// visibility issues around module splitting, including (but not limited to):
34 ///
35 /// - Internal symbols should not collide with symbols defined outside the
36 ///   module.
37 /// - Internal symbols defined in module-level inline asm should be visible to
38 ///   each partition.
39 LLVM_ABI void
40 SplitModule(Module &M, unsigned N,
41             function_ref<void(std::unique_ptr<Module> MPart)> ModuleCallback,
42             bool PreserveLocals = false, bool RoundRobin = false);
43 
44 } // end namespace llvm
45 
46 #endif // LLVM_TRANSFORMS_UTILS_SPLITMODULE_H
47