MachineFunction.cpp revision ce9c41e77a2ec75d48a173b9baf0f4a3bf49fac7 
1//===-- MachineFunction.cpp -----------------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by the LLVM research group and is distributed under
6// the University of Illinois Open Source License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// Collect native machine code information for a function.  This allows
11// target-specific information about the generated code to be stored with each
12// function.
13//
14//===----------------------------------------------------------------------===//
15
16#include "llvm/CodeGen/MachineFunctionPass.h"
17#include "llvm/CodeGen/MachineInstr.h"
18#include "llvm/CodeGen/SSARegMap.h"
19#include "llvm/CodeGen/MachineFrameInfo.h"
20#include "llvm/CodeGen/MachineConstantPool.h"
21#include "llvm/CodeGen/Passes.h"
22#include "llvm/Target/TargetMachine.h"
23#include "llvm/Target/TargetFrameInfo.h"
24#include "llvm/Function.h"
25#include "llvm/Instructions.h"
26#include "llvm/Support/LeakDetector.h"
27#include "llvm/Support/GraphWriter.h"
28#include <fstream>
29#include <iostream>
30#include <sstream>
31
32using namespace llvm;
33
34static AnnotationID MF_AID(
35  AnnotationManager::getID("CodeGen::MachineCodeForFunction"));
36
37
38namespace {
39  struct Printer : public MachineFunctionPass {
40    std::ostream *OS;
41    const std::string Banner;
42
43    Printer (std::ostream *_OS, const std::string &_Banner) :
44      OS (_OS), Banner (_Banner) { }
45
46    const char *getPassName() const { return "MachineFunction Printer"; }
47
48    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
49      AU.setPreservesAll();
50    }
51
52    bool runOnMachineFunction(MachineFunction &MF) {
53      (*OS) << Banner;
54      MF.print (*OS);
55      return false;
56    }
57  };
58}
59
60/// Returns a newly-created MachineFunction Printer pass. The default output
61/// stream is std::cerr; the default banner is empty.
62///
63FunctionPass *llvm::createMachineFunctionPrinterPass(std::ostream *OS,
64                                                     const std::string &Banner){
65  return new Printer(OS, Banner);
66}
67
68namespace {
69  struct Deleter : public MachineFunctionPass {
70    const char *getPassName() const { return "Machine Code Deleter"; }
71
72    bool runOnMachineFunction(MachineFunction &MF) {
73      // Delete the annotation from the function now.
74      MachineFunction::destruct(MF.getFunction());
75      return true;
76    }
77  };
78}
79
80/// MachineCodeDeletion Pass - This pass deletes all of the machine code for
81/// the current function, which should happen after the function has been
82/// emitted to a .s file or to memory.
83FunctionPass *llvm::createMachineCodeDeleter() {
84  return new Deleter();
85}
86
87
88
89//===---------------------------------------------------------------------===//
90// MachineFunction implementation
91//===---------------------------------------------------------------------===//
92MachineBasicBlock* ilist_traits<MachineBasicBlock>::createNode()
93{
94  MachineBasicBlock* dummy = new MachineBasicBlock();
95  LeakDetector::removeGarbageObject(dummy);
96  return dummy;
97}
98
99void ilist_traits<MachineBasicBlock>::transferNodesFromList(
100  iplist<MachineBasicBlock, ilist_traits<MachineBasicBlock> >& toList,
101  ilist_iterator<MachineBasicBlock> first,
102  ilist_iterator<MachineBasicBlock> last)
103{
104  if (Parent != toList.Parent)
105    for (; first != last; ++first)
106      first->Parent = toList.Parent;
107}
108
109MachineFunction::MachineFunction(const Function *F,
110                                 const TargetMachine &TM)
111  : Annotation(MF_AID), Fn(F), Target(TM), UsedPhysRegs(0) {
112  SSARegMapping = new SSARegMap();
113  MFInfo = 0;
114  FrameInfo = new MachineFrameInfo();
115  ConstantPool = new MachineConstantPool();
116  BasicBlocks.Parent = this;
117}
118
119MachineFunction::~MachineFunction() {
120  BasicBlocks.clear();
121  delete SSARegMapping;
122  delete MFInfo;
123  delete FrameInfo;
124  delete ConstantPool;
125  delete[] UsedPhysRegs;
126}
127
128void MachineFunction::dump() const { print(std::cerr); }
129
130void MachineFunction::print(std::ostream &OS) const {
131  OS << "# Machine code for " << Fn->getName () << "():\n";
132
133  // Print Frame Information
134  getFrameInfo()->print(*this, OS);
135
136  // Print Constant Pool
137  getConstantPool()->print(OS);
138
139  for (const_iterator BB = begin(); BB != end(); ++BB)
140    BB->print(OS);
141
142  OS << "\n# End machine code for " << Fn->getName () << "().\n\n";
143}
144
145/// CFGOnly flag - This is used to control whether or not the CFG graph printer
146/// prints out the contents of basic blocks or not.  This is acceptable because
147/// this code is only really used for debugging purposes.
148///
149static bool CFGOnly = false;
150
151namespace llvm {
152  template<>
153  struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits {
154    static std::string getGraphName(const MachineFunction *F) {
155      return "CFG for '" + F->getFunction()->getName() + "' function";
156    }
157
158    static std::string getNodeLabel(const MachineBasicBlock *Node,
159                                    const MachineFunction *Graph) {
160      if (CFGOnly && Node->getBasicBlock() &&
161          !Node->getBasicBlock()->getName().empty())
162        return Node->getBasicBlock()->getName() + ":";
163
164      std::ostringstream Out;
165      if (CFGOnly) {
166        Out << Node->getNumber() << ':';
167        return Out.str();
168      }
169
170      Node->print(Out);
171
172      std::string OutStr = Out.str();
173      if (OutStr[0] == '\n') OutStr.erase(OutStr.begin());
174
175      // Process string output to make it nicer...
176      for (unsigned i = 0; i != OutStr.length(); ++i)
177        if (OutStr[i] == '\n') {                            // Left justify
178          OutStr[i] = '\\';
179          OutStr.insert(OutStr.begin()+i+1, 'l');
180        }
181      return OutStr;
182    }
183  };
184}
185
186void MachineFunction::viewCFG() const
187{
188  std::string Filename = "/tmp/cfg." + getFunction()->getName() + ".dot";
189  std::cerr << "Writing '" << Filename << "'... ";
190  std::ofstream F(Filename.c_str());
191
192  if (!F) {
193    std::cerr << "  error opening file for writing!\n";
194    return;
195  }
196
197  WriteGraph(F, this);
198  F.close();
199  std::cerr << "\n";
200
201  std::cerr << "Running 'dot' program... " << std::flush;
202  if (system(("dot -Tps -Nfontname=Courier -Gsize=7.5,10 " + Filename
203              + " > /tmp/cfg.tempgraph.ps").c_str())) {
204    std::cerr << "Error running dot: 'dot' not in path?\n";
205  } else {
206    std::cerr << "\n";
207    system("gv /tmp/cfg.tempgraph.ps");
208  }
209  system(("rm " + Filename + " /tmp/cfg.tempgraph.ps").c_str());
210}
211
212void MachineFunction::viewCFGOnly() const
213{
214  CFGOnly = true;
215  viewCFG();
216  CFGOnly = false;
217}
218
219// The next two methods are used to construct and to retrieve
220// the MachineCodeForFunction object for the given function.
221// construct() -- Allocates and initializes for a given function and target
222// get()       -- Returns a handle to the object.
223//                This should not be called before "construct()"
224//                for a given Function.
225//
226MachineFunction&
227MachineFunction::construct(const Function *Fn, const TargetMachine &Tar)
228{
229  assert(Fn->getAnnotation(MF_AID) == 0 &&
230         "Object already exists for this function!");
231  MachineFunction* mcInfo = new MachineFunction(Fn, Tar);
232  Fn->addAnnotation(mcInfo);
233  return *mcInfo;
234}
235
236void MachineFunction::destruct(const Function *Fn) {
237  bool Deleted = Fn->deleteAnnotation(MF_AID);
238  assert(Deleted && "Machine code did not exist for function!");
239}
240
241MachineFunction& MachineFunction::get(const Function *F)
242{
243  MachineFunction *mc = (MachineFunction*)F->getAnnotation(MF_AID);
244  assert(mc && "Call construct() method first to allocate the object");
245  return *mc;
246}
247
248void MachineFunction::clearSSARegMap() {
249  delete SSARegMapping;
250  SSARegMapping = 0;
251}
252
253//===----------------------------------------------------------------------===//
254//  MachineFrameInfo implementation
255//===----------------------------------------------------------------------===//
256
257/// CreateStackObject - Create a stack object for a value of the specified type.
258///
259int MachineFrameInfo::CreateStackObject(const Type *Ty, const TargetData &TD) {
260  return CreateStackObject((unsigned)TD.getTypeSize(Ty),
261                           TD.getTypeAlignment(Ty));
262}
263
264
265void MachineFrameInfo::print(const MachineFunction &MF, std::ostream &OS) const{
266  int ValOffset = MF.getTarget().getFrameInfo()->getOffsetOfLocalArea();
267
268  for (unsigned i = 0, e = Objects.size(); i != e; ++i) {
269    const StackObject &SO = Objects[i];
270    OS << "  <fi #" << (int)(i-NumFixedObjects) << "> is ";
271    if (SO.Size == 0)
272      OS << "variable sized";
273    else
274      OS << SO.Size << " byte" << (SO.Size != 1 ? "s" : " ");
275
276    if (i < NumFixedObjects)
277      OS << " fixed";
278    if (i < NumFixedObjects || SO.SPOffset != -1) {
279      int Off = SO.SPOffset - ValOffset;
280      OS << " at location [SP";
281      if (Off > 0)
282        OS << "+" << Off;
283      else if (Off < 0)
284        OS << Off;
285      OS << "]";
286    }
287    OS << "\n";
288  }
289
290  if (HasVarSizedObjects)
291    OS << "  Stack frame contains variable sized objects\n";
292}
293
294void MachineFrameInfo::dump(const MachineFunction &MF) const {
295  print(MF, std::cerr);
296}
297
298
299//===----------------------------------------------------------------------===//
300//  MachineConstantPool implementation
301//===----------------------------------------------------------------------===//
302
303void MachineConstantPool::print(std::ostream &OS) const {
304  for (unsigned i = 0, e = Constants.size(); i != e; ++i)
305    OS << "  <cp #" << i << "> is" << *(Value*)Constants[i] << "\n";
306}
307
308void MachineConstantPool::dump() const { print(std::cerr); }
309