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 "llvm/Config/config.h"
29 #include <fstream>
30 #include <iostream>
31 #include <sstream>
32 
33 using namespace llvm;
34 
35 static AnnotationID MF_AID(
36   AnnotationManager::getID("CodeGen::MachineCodeForFunction"));
37 
38 
39 namespace {
40   struct Printer : public MachineFunctionPass {
41     std::ostream *OS;
42     const std::string Banner;
43 
44     Printer (std::ostream *_OS, const std::string &_Banner) :
45       OS (_OS), Banner (_Banner) { }
46 
47     const char *getPassName() const { return "MachineFunction Printer"; }
48 
49     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
50       AU.setPreservesAll();
51     }
52 
53     bool runOnMachineFunction(MachineFunction &MF) {
54       (*OS) << Banner;
55       MF.print (*OS);
56       return false;
57     }
58   };
59 }
60 
61 /// Returns a newly-created MachineFunction Printer pass. The default output
62 /// stream is std::cerr; the default banner is empty.
63 ///
64 FunctionPass *llvm::createMachineFunctionPrinterPass(std::ostream *OS,
65                                                      const std::string &Banner){
66   return new Printer(OS, Banner);
67 }
68 
69 namespace {
70   struct Deleter : public MachineFunctionPass {
71     const char *getPassName() const { return "Machine Code Deleter"; }
72 
73     bool runOnMachineFunction(MachineFunction &MF) {
74       // Delete the annotation from the function now.
75       MachineFunction::destruct(MF.getFunction());
76       return true;
77     }
78   };
79 }
80 
81 /// MachineCodeDeletion Pass - This pass deletes all of the machine code for
82 /// the current function, which should happen after the function has been
83 /// emitted to a .s file or to memory.
84 FunctionPass *llvm::createMachineCodeDeleter() {
85   return new Deleter();
86 }
87 
88 
89 
90 //===---------------------------------------------------------------------===//
91 // MachineFunction implementation
92 //===---------------------------------------------------------------------===//
93 
94 MachineBasicBlock* ilist_traits<MachineBasicBlock>::createSentinel() {
95   MachineBasicBlock* dummy = new MachineBasicBlock();
96   LeakDetector::removeGarbageObject(dummy);
97   return dummy;
98 }
99 
100 void ilist_traits<MachineBasicBlock>::transferNodesFromList(
101   iplist<MachineBasicBlock, ilist_traits<MachineBasicBlock> >& toList,
102   ilist_iterator<MachineBasicBlock> first,
103   ilist_iterator<MachineBasicBlock> last) {
104   if (Parent != toList.Parent)
105     for (; first != last; ++first)
106       first->Parent = toList.Parent;
107 }
108 
109 MachineFunction::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 
119 MachineFunction::~MachineFunction() {
120   BasicBlocks.clear();
121   delete SSARegMapping;
122   delete MFInfo;
123   delete FrameInfo;
124   delete ConstantPool;
125   delete[] UsedPhysRegs;
126 }
127 
128 void MachineFunction::dump() const { print(std::cerr); }
129 
130 void 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   const MRegisterInfo *MRI = getTarget().getRegisterInfo();
140 
141   if (livein_begin() != livein_end()) {
142     OS << "Live Ins:";
143     for (livein_iterator I = livein_begin(), E = livein_end(); I != E; ++I) {
144       if (MRI)
145         OS << " " << MRI->getName(I->first);
146       else
147         OS << " Reg #" << I->first;
148     }
149     OS << "\n";
150   }
151   if (liveout_begin() != liveout_end()) {
152     OS << "Live Outs:";
153     for (liveout_iterator I = liveout_begin(), E = liveout_end(); I != E; ++I)
154       if (MRI)
155         OS << " " << MRI->getName(*I);
156       else
157         OS << " Reg #" << *I;
158     OS << "\n";
159   }
160 
161   for (const_iterator BB = begin(); BB != end(); ++BB)
162     BB->print(OS);
163 
164   OS << "\n# End machine code for " << Fn->getName () << "().\n\n";
165 }
166 
167 /// CFGOnly flag - This is used to control whether or not the CFG graph printer
168 /// prints out the contents of basic blocks or not.  This is acceptable because
169 /// this code is only really used for debugging purposes.
170 ///
171 static bool CFGOnly = false;
172 
173 namespace llvm {
174   template<>
175   struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits {
176     static std::string getGraphName(const MachineFunction *F) {
177       return "CFG for '" + F->getFunction()->getName() + "' function";
178     }
179 
180     static std::string getNodeLabel(const MachineBasicBlock *Node,
181                                     const MachineFunction *Graph) {
182       if (CFGOnly && Node->getBasicBlock() &&
183           !Node->getBasicBlock()->getName().empty())
184         return Node->getBasicBlock()->getName() + ":";
185 
186       std::ostringstream Out;
187       if (CFGOnly) {
188         Out << Node->getNumber() << ':';
189         return Out.str();
190       }
191 
192       Node->print(Out);
193 
194       std::string OutStr = Out.str();
195       if (OutStr[0] == '\n') OutStr.erase(OutStr.begin());
196 
197       // Process string output to make it nicer...
198       for (unsigned i = 0; i != OutStr.length(); ++i)
199         if (OutStr[i] == '\n') {                            // Left justify
200           OutStr[i] = '\\';
201           OutStr.insert(OutStr.begin()+i+1, 'l');
202         }
203       return OutStr;
204     }
205   };
206 }
207 
208 void MachineFunction::viewCFG() const
209 {
210 #ifndef NDEBUG
211   std::string Filename = "/tmp/cfg." + getFunction()->getName() + ".dot";
212   std::cerr << "Writing '" << Filename << "'... ";
213   std::ofstream F(Filename.c_str());
214 
215   if (!F) {
216     std::cerr << "  error opening file for writing!\n";
217     return;
218   }
219 
220   WriteGraph(F, this);
221   F.close();
222   std::cerr << "\n";
223 
224 #ifdef HAVE_GRAPHVIZ
225   std::cerr << "Running 'Graphviz' program... " << std::flush;
226   if (system((LLVM_PATH_GRAPHVIZ " " + Filename).c_str())) {
227     std::cerr << "Error viewing graph: 'Graphviz' not in path?\n";
228   } else {
229     system(("rm " + Filename).c_str());
230     return;
231   }
232 #endif  // HAVE_GRAPHVIZ
233 
234 #ifdef HAVE_GV
235   std::cerr << "Running 'dot' program... " << std::flush;
236   if (system(("dot -Tps -Nfontname=Courier -Gsize=7.5,10 " + Filename
237               + " > /tmp/cfg.tempgraph.ps").c_str())) {
238     std::cerr << "Error running dot: 'dot' not in path?\n";
239   } else {
240     std::cerr << "\n";
241     system("gv /tmp/cfg.tempgraph.ps");
242   }
243   system(("rm " + Filename + " /tmp/cfg.tempgraph.ps").c_str());
244   return;
245 #endif  // HAVE_GV
246 #endif  // NDEBUG
247   std::cerr << "MachineFunction::viewCFG is only available in debug builds on "
248             << "systems with Graphviz or gv!\n";
249 
250 #ifndef NDEBUG
251   system(("rm " + Filename).c_str());
252 #endif
253 }
254 
255 void MachineFunction::viewCFGOnly() const
256 {
257   CFGOnly = true;
258   viewCFG();
259   CFGOnly = false;
260 }
261 
262 // The next two methods are used to construct and to retrieve
263 // the MachineCodeForFunction object for the given function.
264 // construct() -- Allocates and initializes for a given function and target
265 // get()       -- Returns a handle to the object.
266 //                This should not be called before "construct()"
267 //                for a given Function.
268 //
269 MachineFunction&
270 MachineFunction::construct(const Function *Fn, const TargetMachine &Tar)
271 {
272   assert(Fn->getAnnotation(MF_AID) == 0 &&
273          "Object already exists for this function!");
274   MachineFunction* mcInfo = new MachineFunction(Fn, Tar);
275   Fn->addAnnotation(mcInfo);
276   return *mcInfo;
277 }
278 
279 void MachineFunction::destruct(const Function *Fn) {
280   bool Deleted = Fn->deleteAnnotation(MF_AID);
281   assert(Deleted && "Machine code did not exist for function!");
282 }
283 
284 MachineFunction& MachineFunction::get(const Function *F)
285 {
286   MachineFunction *mc = (MachineFunction*)F->getAnnotation(MF_AID);
287   assert(mc && "Call construct() method first to allocate the object");
288   return *mc;
289 }
290 
291 void MachineFunction::clearSSARegMap() {
292   delete SSARegMapping;
293   SSARegMapping = 0;
294 }
295 
296 //===----------------------------------------------------------------------===//
297 //  MachineFrameInfo implementation
298 //===----------------------------------------------------------------------===//
299 
300 /// CreateStackObject - Create a stack object for a value of the specified type.
301 ///
302 int MachineFrameInfo::CreateStackObject(const Type *Ty, const TargetData &TD) {
303   return CreateStackObject((unsigned)TD.getTypeSize(Ty),
304                            TD.getTypeAlignment(Ty));
305 }
306 
307 
308 void MachineFrameInfo::print(const MachineFunction &MF, std::ostream &OS) const{
309   int ValOffset = MF.getTarget().getFrameInfo()->getOffsetOfLocalArea();
310 
311   for (unsigned i = 0, e = Objects.size(); i != e; ++i) {
312     const StackObject &SO = Objects[i];
313     OS << "  <fi #" << (int)(i-NumFixedObjects) << ">: ";
314     if (SO.Size == 0)
315       OS << "variable sized";
316     else
317       OS << "size is " << SO.Size << " byte" << (SO.Size != 1 ? "s," : ",");
318     OS << " alignment is " << SO.Alignment << " byte"
319        << (SO.Alignment != 1 ? "s," : ",");
320 
321     if (i < NumFixedObjects)
322       OS << " fixed";
323     if (i < NumFixedObjects || SO.SPOffset != -1) {
324       int Off = SO.SPOffset - ValOffset;
325       OS << " at location [SP";
326       if (Off > 0)
327         OS << "+" << Off;
328       else if (Off < 0)
329         OS << Off;
330       OS << "]";
331     }
332     OS << "\n";
333   }
334 
335   if (HasVarSizedObjects)
336     OS << "  Stack frame contains variable sized objects\n";
337 }
338 
339 void MachineFrameInfo::dump(const MachineFunction &MF) const {
340   print(MF, std::cerr);
341 }
342 
343 
344 //===----------------------------------------------------------------------===//
345 //  MachineConstantPool implementation
346 //===----------------------------------------------------------------------===//
347 
348 void MachineConstantPool::print(std::ostream &OS) const {
349   for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
350     OS << "  <cp #" << i << "> is" << *(Value*)Constants[i].first;
351     if (Constants[i].second != 0) OS << " , align=" << Constants[i].second;
352     OS << "\n";
353   }
354 }
355 
356 void MachineConstantPool::dump() const { print(std::cerr); }
357