lib/Analysis/CFGPrinter.cpp

   1 //===- CFGPrinter.cpp - DOT printer for the control flow graph ------------===//
   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 defines a '-dot-cfg' analysis pass, which emits the
  11 // cfg.<fnname>.dot file for each function in the program, with a graph of the
  12 // CFG for that function.
  13 //
  14 // The other main feature of this file is that it implements the
  15 // Function::viewCFG method, which is useful for debugging passes which operate
  16 // on the CFG.
  17 //
  18 //===----------------------------------------------------------------------===//
  19
  20 #include "llvm/Analysis/CFGPrinter.h"
  21
  22 #include "llvm/Pass.h"
  23 using namespace llvm;
  24
  25 namespace {
  26   struct CFGViewer : public FunctionPass {
  27     static char ID; // Pass identifcation, replacement for typeid
  28     CFGViewer() : FunctionPass(ID) {
  29       initializeCFGOnlyViewerPass(*PassRegistry::getPassRegistry());
  30     }
  31
  32     virtual bool runOnFunction(Function &F) {
  33       F.viewCFG();
  34       return false;
  35     }
  36
  37     void print(raw_ostream &OS, const Module* = 0) const {}
  38
  39     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
  40       AU.setPreservesAll();
  41     }
  42   };
  43 }
  44
  45 char CFGViewer::ID = 0;
  46 INITIALIZE_PASS(CFGViewer, "view-cfg", "View CFG of function", false, true)
  47
  48 namespace {
  49   struct CFGOnlyViewer : public FunctionPass {
  50     static char ID; // Pass identifcation, replacement for typeid
  51     CFGOnlyViewer() : FunctionPass(ID) {
  52       initializeCFGOnlyViewerPass(*PassRegistry::getPassRegistry());
  53     }
  54
  55     virtual bool runOnFunction(Function &F) {
  56       F.viewCFGOnly();
  57       return false;
  58     }
  59
  60     void print(raw_ostream &OS, const Module* = 0) const {}
  61
  62     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
  63       AU.setPreservesAll();
  64     }
  65   };
  66 }
  67
  68 char CFGOnlyViewer::ID = 0;
  69 INITIALIZE_PASS(CFGOnlyViewer, "view-cfg-only",
  70                 "View CFG of function (with no function bodies)", false, true)
  71
  72 namespace {
  73   struct CFGPrinter : public FunctionPass {
  74     static char ID; // Pass identification, replacement for typeid
  75     CFGPrinter() : FunctionPass(ID) {
  76       initializeCFGPrinterPass(*PassRegistry::getPassRegistry());
  77     }
  78
  79     virtual bool runOnFunction(Function &F) {
  80       std::string Filename = "cfg." + F.getNameStr() + ".dot";
  81       errs() << "Writing '" << Filename << "'...";
  82
  83       std::string ErrorInfo;
  84       raw_fd_ostream File(Filename.c_str(), ErrorInfo);
  85
  86       if (ErrorInfo.empty())
  87         WriteGraph(File, (const Function*)&F);
  88       else
  89         errs() << "  error opening file for writing!";
  90       errs() << "\n";
  91       return false;
  92     }
  93
  94     void print(raw_ostream &OS, const Module* = 0) const {}
  95
  96     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
  97       AU.setPreservesAll();
  98     }
  99   };
 100 }
 101
 102 char CFGPrinter::ID = 0;
 103 INITIALIZE_PASS(CFGPrinter, "dot-cfg", "Print CFG of function to 'dot' file",
 104                 false, true)
 105
 106 namespace {
 107   struct CFGOnlyPrinter : public FunctionPass {
 108     static char ID; // Pass identification, replacement for typeid
 109     CFGOnlyPrinter() : FunctionPass(ID) {
 110       initializeCFGOnlyPrinterPass(*PassRegistry::getPassRegistry());
 111     }
 112
 113     virtual bool runOnFunction(Function &F) {
 114       std::string Filename = "cfg." + F.getNameStr() + ".dot";
 115       errs() << "Writing '" << Filename << "'...";
 116
 117       std::string ErrorInfo;
 118       raw_fd_ostream File(Filename.c_str(), ErrorInfo);
 119
 120       if (ErrorInfo.empty())
 121         WriteGraph(File, (const Function*)&F, true);
 122       else
 123         errs() << "  error opening file for writing!";
 124       errs() << "\n";
 125       return false;
 126     }
 127     void print(raw_ostream &OS, const Module* = 0) const {}
 128
 129     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
 130       AU.setPreservesAll();
 131     }
 132   };
 133 }
 134
 135 char CFGOnlyPrinter::ID = 0;
 136 INITIALIZE_PASS(CFGOnlyPrinter, "dot-cfg-only",
 137    "Print CFG of function to 'dot' file (with no function bodies)",
 138    false, true)
 139
 140 /// viewCFG - This function is meant for use from the debugger.  You can just
 141 /// say 'call F->viewCFG()' and a ghostview window should pop up from the
 142 /// program, displaying the CFG of the current function.  This depends on there
 143 /// being a 'dot' and 'gv' program in your path.
 144 ///
 145 void Function::viewCFG() const {
 146   ViewGraph(this, "cfg" + getNameStr());
 147 }
 148
 149 /// viewCFGOnly - This function is meant for use from the debugger.  It works
 150 /// just like viewCFG, but it does not include the contents of basic blocks
 151 /// into the nodes, just the label.  If you are only interested in the CFG t
 152 /// his can make the graph smaller.
 153 ///
 154 void Function::viewCFGOnly() const {
 155   ViewGraph(this, "cfg" + getNameStr(), true);
 156 }
 157
 158 FunctionPass *llvm::createCFGPrinterPass () {
 159   return new CFGPrinter();
 160 }
 161
 162 FunctionPass *llvm::createCFGOnlyPrinterPass () {
 163   return new CFGOnlyPrinter();
 164 }
 165