TableGen subtarget emitter. Generate resolveSchedClass generated hook for resolving instruction variants.

llvm-svn: 164095

llvm/utils/TableGen/SubtargetEmitter.cpp

@@ -87,6 +87,7 @@ class SubtargetEmitter {
   void EmitSchedClassTables(SchedClassTables &SchedTables, raw_ostream &OS);
   void EmitProcessorModels(raw_ostream &OS);
   void EmitProcessorLookup(raw_ostream &OS);
+  void EmitSchedModelHelpers(std::string ClassName, raw_ostream &OS);
   void EmitSchedModel(raw_ostream &OS);
   void ParseFeaturesFunction(raw_ostream &OS, unsigned NumFeatures,
                              unsigned NumProcs);
@@ -1109,6 +1110,85 @@ void SubtargetEmitter::EmitSchedModel(raw_ostream &OS) {
   OS << "#undef DBGFIELD";
 }
 
+void SubtargetEmitter::EmitSchedModelHelpers(std::string ClassName,
+                                             raw_ostream &OS) {
+  OS << "unsigned " << ClassName
+     << "\n::resolveSchedClass(unsigned SchedClass, const MachineInstr *MI,"
+     << " const TargetSchedModel *SchedModel) const {\n";
+
+  std::vector<Record*> Prologs = Records.getAllDerivedDefinitions("PredicateProlog");
+  std::sort(Prologs.begin(), Prologs.end(), LessRecord());
+  for (std::vector<Record*>::const_iterator
+         PI = Prologs.begin(), PE = Prologs.end(); PI != PE; ++PI) {
+    OS << (*PI)->getValueAsString("Code") << '\n';
+  }
+  IdxVec VariantClasses;
+  for (CodeGenSchedModels::SchedClassIter SCI = SchedModels.schedClassBegin(),
+         SCE = SchedModels.schedClassEnd(); SCI != SCE; ++SCI) {
+    if (SCI->Transitions.empty())
+      continue;
+    VariantClasses.push_back(SCI - SchedModels.schedClassBegin());
+  }
+  if (!VariantClasses.empty()) {
+    OS << "  switch (SchedClass) {\n";
+    for (IdxIter VCI = VariantClasses.begin(), VCE = VariantClasses.end();
+         VCI != VCE; ++VCI) {
+      const CodeGenSchedClass &SC = SchedModels.getSchedClass(*VCI);
+      OS << "  case " << *VCI << ": // " << SC.Name << '\n';
+      IdxVec ProcIndices;
+      for (std::vector<CodeGenSchedTransition>::const_iterator
+             TI = SC.Transitions.begin(), TE = SC.Transitions.end();
+           TI != TE; ++TI) {
+        IdxVec PI;
+        std::set_union(TI->ProcIndices.begin(), TI->ProcIndices.end(),
+                       ProcIndices.begin(), ProcIndices.end(),
+                       std::back_inserter(PI));
+        ProcIndices.swap(PI);
+      }
+      for (IdxIter PI = ProcIndices.begin(), PE = ProcIndices.end();
+           PI != PE; ++PI) {
+        OS << "    ";
+        if (*PI != 0)
+          OS << "if (SchedModel->getProcessorID() == " << *PI << ") ";
+        OS << "{ // " << (SchedModels.procModelBegin() + *PI)->ModelName
+           << '\n';
+        for (std::vector<CodeGenSchedTransition>::const_iterator
+               TI = SC.Transitions.begin(), TE = SC.Transitions.end();
+             TI != TE; ++TI) {
+          OS << "      if (";
+          if (*PI != 0 && !std::count(TI->ProcIndices.begin(),
+                                      TI->ProcIndices.end(), *PI)) {
+              continue;
+          }
+          for (RecIter RI = TI->PredTerm.begin(), RE = TI->PredTerm.end();
+               RI != RE; ++RI) {
+            if (RI != TI->PredTerm.begin())
+              OS << "\n          && ";
+            OS << "(" << (*RI)->getValueAsString("Predicate") << ")";
+          }
+          OS << ")\n"
+             << "        return " << TI->ToClassIdx << "; // "
+             << SchedModels.getSchedClass(TI->ToClassIdx).Name << '\n';
+        }
+        OS << "    }\n";
+        if (*PI == 0)
+          break;
+      }
+      unsigned SCIdx = 0;
+      if (SC.ItinClassDef)
+        SCIdx = SchedModels.getSchedClassIdxForItin(SC.ItinClassDef);
+      else
+        SCIdx = SchedModels.findSchedClassIdx(SC.Writes, SC.Reads);
+      if (SCIdx != *VCI)
+        OS << "    return " << SCIdx << ";\n";
+      OS << "    break;\n";
+    }
+    OS << "  };\n";
+  }
+  OS << "  report_fatal_error(\"Expected a variant SchedClass\");\n"
+     << "} // " << ClassName << "::resolveSchedClass\n";
+}
+
 //
 // ParseFeaturesFunction - Produces a subtarget specific function for parsing
 // the subtarget features string.
@@ -1238,6 +1318,8 @@ void SubtargetEmitter::run(raw_ostream &OS) {
      << "  explicit " << ClassName << "(StringRef TT, StringRef CPU, "
      << "StringRef FS);\n"
      << "public:\n"
+     << "  unsigned resolveSchedClass(unsigned SchedClass, const MachineInstr *DefMI,"
+     << " const TargetSchedModel *SchedModel) const;\n"
      << "  DFAPacketizer *createDFAPacketizer(const InstrItineraryData *IID)"
      << " const;\n"
      << "};\n";
@@ -1292,6 +1374,8 @@ void SubtargetEmitter::run(raw_ostream &OS) {
     OS << "0, 0, 0, ";
   OS << NumFeatures << ", " << NumProcs << ");\n}\n\n";
 
+  EmitSchedModelHelpers(ClassName, OS);
+
   OS << "} // End llvm namespace \n";
 
   OS << "#endif // GET_SUBTARGETINFO_CTOR\n\n";