File: BarrierNoopPass.cpp

package info (click to toggle)
llvm-toolchain-3.7 1%3A3.7.1-5
  • links: PTS, VCS
  • area: main
  • in suites: stretch
  • size: 345,556 kB
  • ctags: 362,199
  • sloc: cpp: 2,156,381; ansic: 458,339; objc: 91,547; python: 89,988; asm: 86,305; sh: 21,479; makefile: 6,853; perl: 5,601; ml: 5,458; pascal: 3,933; lisp: 2,429; xml: 686; cs: 239; php: 202; csh: 117
file content (47 lines) | stat: -rw-r--r-- 1,655 bytes parent folder | download | duplicates (13)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
//===- BarrierNoopPass.cpp - A barrier pass for the pass manager ----------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// NOTE: DO NOT USE THIS IF AVOIDABLE
//
// This pass is a nonce pass intended to allow manipulation of the implicitly
// nesting pass manager. For example, it can be used to cause a CGSCC pass
// manager to be closed prior to running a new collection of function passes.
//
// FIXME: This is a huge HACK. This should be removed when the pass manager's
// nesting is made explicit instead of implicit.
//
//===----------------------------------------------------------------------===//

#include "llvm/Pass.h"
#include "llvm/Transforms/IPO.h"
using namespace llvm;

namespace {
/// \brief A nonce module pass used to place a barrier in a pass manager.
///
/// There is no mechanism for ending a CGSCC pass manager once one is started.
/// This prevents extension points from having clear deterministic ordering
/// when they are phrased as non-module passes.
class BarrierNoop : public ModulePass {
public:
  static char ID; // Pass identification.

  BarrierNoop() : ModulePass(ID) {
    initializeBarrierNoopPass(*PassRegistry::getPassRegistry());
  }

  bool runOnModule(Module &M) override { return false; }
};
}

ModulePass *llvm::createBarrierNoopPass() { return new BarrierNoop(); }

char BarrierNoop::ID = 0;
INITIALIZE_PASS(BarrierNoop, "barrier", "A No-Op Barrier Pass",
                false, false)