File: OrderedInstructions.cpp

package info (click to toggle)
llvm-toolchain-7 1%3A7.0.1-8~deb9u3
  • links: PTS, VCS
  • area: main
  • in suites: stretch
  • size: 733,456 kB
  • sloc: cpp: 3,776,651; ansic: 633,271; asm: 350,301; python: 142,716; objc: 107,612; sh: 22,626; lisp: 11,056; perl: 7,999; pascal: 6,742; ml: 5,537; awk: 3,536; makefile: 2,557; cs: 2,027; xml: 841; ruby: 156
file content (51 lines) | stat: -rw-r--r-- 2,101 bytes parent folder | download | duplicates (3)
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
48
49
50
51
//===-- OrderedInstructions.cpp - Instruction dominance function ---------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines utility to check dominance relation of 2 instructions.
//
//===----------------------------------------------------------------------===//

#include "llvm/Transforms/Utils/OrderedInstructions.h"
using namespace llvm;

bool OrderedInstructions::localDominates(const Instruction *InstA,
                                         const Instruction *InstB) const {
  assert(InstA->getParent() == InstB->getParent() &&
         "Instructions must be in the same basic block");

  const BasicBlock *IBB = InstA->getParent();
  auto OBB = OBBMap.find(IBB);
  if (OBB == OBBMap.end())
    OBB = OBBMap.insert({IBB, make_unique<OrderedBasicBlock>(IBB)}).first;
  return OBB->second->dominates(InstA, InstB);
}

/// Given 2 instructions, use OrderedBasicBlock to check for dominance relation
/// if the instructions are in the same basic block, Otherwise, use dominator
/// tree.
bool OrderedInstructions::dominates(const Instruction *InstA,
                                    const Instruction *InstB) const {
  // Use ordered basic block to do dominance check in case the 2 instructions
  // are in the same basic block.
  if (InstA->getParent() == InstB->getParent())
    return localDominates(InstA, InstB);
  return DT->dominates(InstA->getParent(), InstB->getParent());
}

bool OrderedInstructions::dfsBefore(const Instruction *InstA,
                                    const Instruction *InstB) const {
  // Use ordered basic block in case the 2 instructions are in the same basic
  // block.
  if (InstA->getParent() == InstB->getParent())
    return localDominates(InstA, InstB);

  DomTreeNode *DA = DT->getNode(InstA->getParent());
  DomTreeNode *DB = DT->getNode(InstB->getParent());
  return DA->getDFSNumIn() < DB->getDFSNumIn();
}