1 //===-- JSONExporter.cpp  - Export Scops as JSON  -------------------------===//
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 // Export the Scops build by ScopInfo pass as a JSON file.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "polly/LinkAllPasses.h"
15 #include "polly/Dependences.h"
16 #include "polly/Options.h"
17 #include "polly/ScopInfo.h"
18 #include "polly/ScopPass.h"
19 #include "llvm/ADT/Statistic.h"
20 #include "llvm/Support/FileSystem.h"
21 #include "llvm/Support/MemoryBuffer.h"
22 #include "llvm/Support/ToolOutputFile.h"
23 
24 #include "json/reader.h"
25 #include "json/writer.h"
26 
27 #include "isl/set.h"
28 #include "isl/map.h"
29 #include "isl/constraint.h"
30 #include "isl/printer.h"
31 
32 #include <memory>
33 #include <string>
34 #include <system_error>
35 
36 using namespace llvm;
37 using namespace polly;
38 
39 #define DEBUG_TYPE "polly-import-jscop"
40 
41 STATISTIC(NewAccessMapFound, "Number of updated access functions");
42 
43 namespace {
44 static cl::opt<std::string>
45 ImportDir("polly-import-jscop-dir",
46           cl::desc("The directory to import the .jscop files from."),
47           cl::Hidden, cl::value_desc("Directory path"), cl::ValueRequired,
48           cl::init("."), cl::cat(PollyCategory));
49 
50 static cl::opt<std::string>
51 ImportPostfix("polly-import-jscop-postfix",
52               cl::desc("Postfix to append to the import .jsop files."),
53               cl::Hidden, cl::value_desc("File postfix"), cl::ValueRequired,
54               cl::init(""), cl::cat(PollyCategory));
55 
56 struct JSONExporter : public ScopPass {
57   static char ID;
58   Scop *S;
59   explicit JSONExporter() : ScopPass(ID) {}
60 
61   std::string getFileName(Scop *S) const;
62   Json::Value getJSON(Scop &scop) const;
63   virtual bool runOnScop(Scop &S);
64   void printScop(raw_ostream &OS) const;
65   void getAnalysisUsage(AnalysisUsage &AU) const;
66 };
67 
68 struct JSONImporter : public ScopPass {
69   static char ID;
70   Scop *S;
71   std::vector<std::string> newAccessStrings;
72   explicit JSONImporter() : ScopPass(ID) {}
73 
74   std::string getFileName(Scop *S) const;
75   virtual bool runOnScop(Scop &S);
76   void printScop(raw_ostream &OS) const;
77   void getAnalysisUsage(AnalysisUsage &AU) const;
78 };
79 }
80 
81 char JSONExporter::ID = 0;
82 std::string JSONExporter::getFileName(Scop *S) const {
83   std::string FunctionName = S->getRegion().getEntry()->getParent()->getName();
84   std::string FileName = FunctionName + "___" + S->getNameStr() + ".jscop";
85   return FileName;
86 }
87 
88 void JSONExporter::printScop(raw_ostream &OS) const { S->print(OS); }
89 
90 Json::Value JSONExporter::getJSON(Scop &scop) const {
91   Json::Value root;
92 
93   root["name"] = S->getRegion().getNameStr();
94   root["context"] = S->getContextStr();
95   root["statements"];
96 
97   for (Scop::iterator SI = S->begin(), SE = S->end(); SI != SE; ++SI) {
98     ScopStmt *Stmt = *SI;
99 
100     Json::Value statement;
101 
102     statement["name"] = Stmt->getBaseName();
103     statement["domain"] = Stmt->getDomainStr();
104     statement["schedule"] = Stmt->getScatteringStr();
105     statement["accesses"];
106 
107     for (MemoryAccess *MA : *Stmt) {
108       Json::Value access;
109 
110       access["kind"] = MA->isRead() ? "read" : "write";
111       access["relation"] = MA->getAccessRelationStr();
112 
113       statement["accesses"].append(access);
114     }
115 
116     root["statements"].append(statement);
117   }
118 
119   return root;
120 }
121 
122 bool JSONExporter::runOnScop(Scop &scop) {
123   S = &scop;
124   Region &R = S->getRegion();
125 
126   std::string FileName = ImportDir + "/" + getFileName(S);
127 
128   Json::Value jscop = getJSON(scop);
129   Json::StyledWriter writer;
130   std::string fileContent = writer.write(jscop);
131 
132   // Write to file.
133   std::string ErrInfo;
134   tool_output_file F(FileName.c_str(), ErrInfo, llvm::sys::fs::F_Text);
135 
136   std::string FunctionName = R.getEntry()->getParent()->getName();
137   errs() << "Writing JScop '" << R.getNameStr() << "' in function '"
138          << FunctionName << "' to '" << FileName << "'.\n";
139 
140   if (ErrInfo.empty()) {
141     F.os() << fileContent;
142     F.os().close();
143     if (!F.os().has_error()) {
144       errs() << "\n";
145       F.keep();
146       return false;
147     }
148   }
149 
150   errs() << "  error opening file for writing!\n";
151   F.os().clear_error();
152 
153   return false;
154 }
155 
156 void JSONExporter::getAnalysisUsage(AnalysisUsage &AU) const {
157   AU.setPreservesAll();
158   AU.addRequired<ScopInfo>();
159 }
160 
161 Pass *polly::createJSONExporterPass() { return new JSONExporter(); }
162 
163 char JSONImporter::ID = 0;
164 std::string JSONImporter::getFileName(Scop *S) const {
165   std::string FunctionName = S->getRegion().getEntry()->getParent()->getName();
166   std::string FileName = FunctionName + "___" + S->getNameStr() + ".jscop";
167 
168   if (ImportPostfix != "")
169     FileName += "." + ImportPostfix;
170 
171   return FileName;
172 }
173 
174 void JSONImporter::printScop(raw_ostream &OS) const {
175   S->print(OS);
176   for (std::vector<std::string>::const_iterator I = newAccessStrings.begin(),
177                                                 E = newAccessStrings.end();
178        I != E; I++)
179     OS << "New access function '" << *I << "'detected in JSCOP file\n";
180 }
181 
182 typedef Dependences::StatementToIslMapTy StatementToIslMapTy;
183 
184 bool JSONImporter::runOnScop(Scop &scop) {
185   S = &scop;
186   Region &R = S->getRegion();
187   Dependences *D = &getAnalysis<Dependences>();
188 
189   std::string FileName = ImportDir + "/" + getFileName(S);
190 
191   std::string FunctionName = R.getEntry()->getParent()->getName();
192   errs() << "Reading JScop '" << R.getNameStr() << "' in function '"
193          << FunctionName << "' from '" << FileName << "'.\n";
194   std::unique_ptr<MemoryBuffer> result;
195   std::error_code ec = MemoryBuffer::getFile(FileName, result);
196 
197   if (ec) {
198     errs() << "File could not be read: " << ec.message() << "\n";
199     return false;
200   }
201 
202   Json::Reader reader;
203   Json::Value jscop;
204 
205   bool parsingSuccessful = reader.parse(result->getBufferStart(), jscop);
206 
207   if (!parsingSuccessful) {
208     errs() << "JSCoP file could not be parsed\n";
209     return false;
210   }
211 
212   isl_set *OldContext = S->getContext();
213   isl_set *NewContext =
214       isl_set_read_from_str(S->getIslCtx(), jscop["context"].asCString());
215 
216   for (unsigned i = 0; i < isl_set_dim(OldContext, isl_dim_param); i++) {
217     isl_id *id = isl_set_get_dim_id(OldContext, isl_dim_param, i);
218     NewContext = isl_set_set_dim_id(NewContext, isl_dim_param, i, id);
219   }
220 
221   isl_set_free(OldContext);
222   S->setContext(NewContext);
223 
224   StatementToIslMapTy &NewScattering = *(new StatementToIslMapTy());
225 
226   int index = 0;
227 
228   for (Scop::iterator SI = S->begin(), SE = S->end(); SI != SE; ++SI) {
229     Json::Value schedule = jscop["statements"][index]["schedule"];
230     isl_map *m = isl_map_read_from_str(S->getIslCtx(), schedule.asCString());
231     isl_space *Space = (*SI)->getDomainSpace();
232 
233     // Copy the old tuple id. This is necessary to retain the user pointer,
234     // that stores the reference to the ScopStmt this scattering belongs to.
235     m = isl_map_set_tuple_id(m, isl_dim_in,
236                              isl_space_get_tuple_id(Space, isl_dim_set));
237     isl_space_free(Space);
238     NewScattering[*SI] = m;
239     index++;
240   }
241 
242   if (!D->isValidScattering(&NewScattering)) {
243     errs() << "JScop file contains a scattering that changes the "
244            << "dependences. Use -disable-polly-legality to continue anyways\n";
245     for (StatementToIslMapTy::iterator SI = NewScattering.begin(),
246                                        SE = NewScattering.end();
247          SI != SE; ++SI)
248       isl_map_free(SI->second);
249     return false;
250   }
251 
252   for (Scop::iterator SI = S->begin(), SE = S->end(); SI != SE; ++SI) {
253     ScopStmt *Stmt = *SI;
254 
255     if (NewScattering.find(Stmt) != NewScattering.end())
256       Stmt->setScattering(NewScattering[Stmt]);
257   }
258 
259   int statementIdx = 0;
260   for (Scop::iterator SI = S->begin(), SE = S->end(); SI != SE; ++SI) {
261     ScopStmt *Stmt = *SI;
262 
263     int memoryAccessIdx = 0;
264     for (MemoryAccess *MA : *Stmt) {
265       Json::Value accesses = jscop["statements"][statementIdx]["accesses"]
266                                   [memoryAccessIdx]["relation"];
267       isl_map *newAccessMap =
268           isl_map_read_from_str(S->getIslCtx(), accesses.asCString());
269       isl_map *currentAccessMap = MA->getAccessRelation();
270 
271       if (isl_map_dim(newAccessMap, isl_dim_param) !=
272           isl_map_dim(currentAccessMap, isl_dim_param)) {
273         errs() << "JScop file changes the number of parameter dimensions\n";
274         isl_map_free(currentAccessMap);
275         isl_map_free(newAccessMap);
276         return false;
277       }
278 
279       // We need to copy the isl_ids for the parameter dimensions to the new
280       // map. Without doing this the current map would have different
281       // ids then the new one, even though both are named identically.
282       for (unsigned i = 0; i < isl_map_dim(currentAccessMap, isl_dim_param);
283            i++) {
284         isl_id *id = isl_map_get_dim_id(currentAccessMap, isl_dim_param, i);
285         newAccessMap = isl_map_set_dim_id(newAccessMap, isl_dim_param, i, id);
286       }
287 
288       // Copy the old tuple id. This is necessary to retain the user pointer,
289       // that stores the reference to the ScopStmt this access belongs to.
290       isl_id *Id = isl_map_get_tuple_id(currentAccessMap, isl_dim_in);
291       newAccessMap = isl_map_set_tuple_id(newAccessMap, isl_dim_in, Id);
292 
293       if (!isl_map_has_equal_space(currentAccessMap, newAccessMap)) {
294         errs() << "JScop file contains access function with incompatible "
295                << "dimensions\n";
296         isl_map_free(currentAccessMap);
297         isl_map_free(newAccessMap);
298         return false;
299       }
300       if (isl_map_dim(newAccessMap, isl_dim_out) != 1) {
301         errs() << "New access map in JScop file should be single dimensional\n";
302         isl_map_free(currentAccessMap);
303         isl_map_free(newAccessMap);
304         return false;
305       }
306       if (!isl_map_is_equal(newAccessMap, currentAccessMap)) {
307         // Statistics.
308         ++NewAccessMapFound;
309         newAccessStrings.push_back(accesses.asCString());
310         MA->setNewAccessRelation(newAccessMap);
311       } else {
312         isl_map_free(newAccessMap);
313       }
314       isl_map_free(currentAccessMap);
315       memoryAccessIdx++;
316     }
317     statementIdx++;
318   }
319 
320   return false;
321 }
322 
323 void JSONImporter::getAnalysisUsage(AnalysisUsage &AU) const {
324   ScopPass::getAnalysisUsage(AU);
325   AU.addRequired<Dependences>();
326 }
327 Pass *polly::createJSONImporterPass() { return new JSONImporter(); }
328 
329 INITIALIZE_PASS_BEGIN(JSONExporter, "polly-export-jscop",
330                       "Polly - Export Scops as JSON"
331                       " (Writes a .jscop file for each Scop)",
332                       false, false);
333 INITIALIZE_PASS_DEPENDENCY(Dependences)
334 INITIALIZE_PASS_END(JSONExporter, "polly-export-jscop",
335                     "Polly - Export Scops as JSON"
336                     " (Writes a .jscop file for each Scop)",
337                     false, false)
338 
339 INITIALIZE_PASS_BEGIN(JSONImporter, "polly-import-jscop",
340                       "Polly - Import Scops from JSON"
341                       " (Reads a .jscop file for each Scop)",
342                       false, false);
343 INITIALIZE_PASS_DEPENDENCY(Dependences)
344 INITIALIZE_PASS_END(JSONImporter, "polly-import-jscop",
345                     "Polly - Import Scops from JSON"
346                     " (Reads a .jscop file for each Scop)",
347                     false, false)
348