1//===----------------------- MIRNamer.cpp - MIR Namer ---------------------===//
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// The purpose of this pass is to rename virtual register operands with the goal
10// of making it easier to author easier to read tests for MIR. This pass reuses
11// the vreg renamer used by MIRCanonicalizerPass.
12//
13// Basic Usage:
14//
15// llc -o - -run-pass mir-namer example.mir
16//
17//===----------------------------------------------------------------------===//
18
19#include "MIRVRegNamerUtils.h"
20#include "llvm/ADT/PostOrderIterator.h"
21#include "llvm/ADT/STLExtras.h"
22#include "llvm/CodeGen/MachineFunctionPass.h"
23#include "llvm/CodeGen/MachineInstrBuilder.h"
24#include "llvm/CodeGen/MachineRegisterInfo.h"
25#include "llvm/CodeGen/Passes.h"
26#include "llvm/InitializePasses.h"
27
28using namespace llvm;
29
30namespace llvm {
31extern char &MIRNamerID;
32} // namespace llvm
33
34#define DEBUG_TYPE "mir-namer"
35
36namespace {
37
38class MIRNamer : public MachineFunctionPass {
39public:
40  static char ID;
41  MIRNamer() : MachineFunctionPass(ID) {}
42
43  StringRef getPassName() const override {
44    return "Rename virtual register operands";
45  }
46
47  void getAnalysisUsage(AnalysisUsage &AU) const override {
48    AU.setPreservesCFG();
49    MachineFunctionPass::getAnalysisUsage(AU);
50  }
51
52  bool runOnMachineFunction(MachineFunction &MF) override {
53    bool Changed = false;
54
55    if (MF.empty())
56      return Changed;
57
58    VRegRenamer Renamer(MF.getRegInfo());
59
60    unsigned BBIndex = 0;
61    ReversePostOrderTraversal<MachineBasicBlock *> RPOT(&*MF.begin());
62    for (auto &MBB : RPOT)
63      Changed |= Renamer.renameVRegs(MBB, BBIndex++);
64
65    return Changed;
66  }
67};
68
69} // end anonymous namespace
70
71char MIRNamer::ID;
72
73char &llvm::MIRNamerID = MIRNamer::ID;
74
75INITIALIZE_PASS_BEGIN(MIRNamer, "mir-namer", "Rename Register Operands", false,
76                      false)
77
78INITIALIZE_PASS_END(MIRNamer, "mir-namer", "Rename Register Operands", false,
79                    false)
80