1 //===- Interval.cpp - Interval class code ---------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file contains the definition of the Interval class, which represents a
11 // partition of a control flow graph of some kind.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "llvm/Analysis/Interval.h"
16 #include "llvm/IR/BasicBlock.h"
17 #include "llvm/IR/CFG.h"
18 #include "llvm/Support/raw_ostream.h"
19 #include <algorithm>
20 
21 using namespace llvm;
22 
23 //===----------------------------------------------------------------------===//
24 // Interval Implementation
25 //===----------------------------------------------------------------------===//
26 
27 // isLoop - Find out if there is a back edge in this interval...
28 //
29 bool Interval::isLoop() const {
30   // There is a loop in this interval iff one of the predecessors of the header
31   // node lives in the interval.
32   for (BasicBlock *Pred : predecessors(HeaderNode))
33     if (contains(Pred))
34       return true;
35   return false;
36 }
37 
38 
39 void Interval::print(raw_ostream &OS) const {
40   OS << "-------------------------------------------------------------\n"
41        << "Interval Contents:\n";
42 
43   // Print out all of the basic blocks in the interval...
44   for (std::vector<BasicBlock*>::const_iterator I = Nodes.begin(),
45          E = Nodes.end(); I != E; ++I)
46     OS << **I << "\n";
47 
48   OS << "Interval Predecessors:\n";
49   for (std::vector<BasicBlock*>::const_iterator I = Predecessors.begin(),
50          E = Predecessors.end(); I != E; ++I)
51     OS << **I << "\n";
52 
53   OS << "Interval Successors:\n";
54   for (std::vector<BasicBlock*>::const_iterator I = Successors.begin(),
55          E = Successors.end(); I != E; ++I)
56     OS << **I << "\n";
57 }
58