[llvm-commits] [llvm] r113171 - /llvm/trunk/utils/TableGen/AsmMatcherEmitter.cpp

[Chris Lattner]

Author: lattner
Date: Mon Sep  6 16:22:45 2010
New Revision: 113171

URL: http://llvm.org/viewvc/llvm-project?rev=113171&view=rev
Log:
now that the opcode is trivially exposed, start matching instructions
by doing a binary search over the mnemonic instead of doing a linear
search through all possible instructions.  This implements rdar://7785064

Modified:
    llvm/trunk/utils/TableGen/AsmMatcherEmitter.cpp

Modified: llvm/trunk/utils/TableGen/AsmMatcherEmitter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/utils/TableGen/AsmMatcherEmitter.cpp?rev=113171&r1=113170&r2=113171&view=diff
==============================================================================
--- llvm/trunk/utils/TableGen/AsmMatcherEmitter.cpp (original)
+++ llvm/trunk/utils/TableGen/AsmMatcherEmitter.cpp Mon Sep  6 16:22:45 2010
@@ -1629,7 +1629,18 @@
   OS << "    ConversionKind ConvertFn;\n";
   OS << "    MatchClassKind Classes[" << MaxNumOperands << "];\n";
   OS << "    unsigned RequiredFeatures;\n";
+  OS << "  };\n\n";
+  
+  OS << "// Predicate for searching for an opcode.\n";
+  OS << "  struct LessOpcode {\n";
+  OS << "    bool operator()(const MatchEntry &LHS, StringRef RHS) {\n";
+  OS << "      return StringRef(LHS.Mnemonic) < RHS;\n";
+  OS << "    }\n";
+  OS << "    bool operator()(StringRef LHS, const MatchEntry &RHS) {\n";
+  OS << "      return LHS < StringRef(RHS.Mnemonic);\n";
+  OS << "    }\n";
   OS << "  };\n";
+  
   OS << "} // end anonymous namespace.\n\n";
   
   OS << "static const MatchEntry MatchTable["
@@ -1699,16 +1710,21 @@
   OS << "  // Get the instruction mneumonic, which is the first token.\n";
   OS << "  StringRef Mnemonic = ((" << Target.getName()
      << "Operand*)Operands[0])->getToken();\n\n";
-  
+
+  OS << "  bool HadMatchOtherThanFeatures = false;\n\n";
+
   // Emit code to search the table.
   OS << "  // Search the table.\n";
-  OS << "  bool HadMatchOtherThanFeatures = false;\n";
-  OS << "  for (const MatchEntry *it = MatchTable, "
-     << "*ie = MatchTable + " << Info.Instructions.size()
-     << "; it != ie; ++it) {\n";
+  OS << "  std::pair<const MatchEntry*, const MatchEntry*> MnemonicRange =\n";
+  OS << "    std::equal_range(MatchTable, MatchTable+"
+     << Info.Instructions.size() << ", Mnemonic, LessOpcode());\n\n";
+  
+  OS << "  for (const MatchEntry *it = MnemonicRange.first, "
+     << "*ie = MnemonicRange.second;\n"
+  OS << "       it != ie; ++it) {\n";
 
   OS << "    // Instruction mneumonic must match.\n";
-  OS << "    if (Mnemonic != it->Mnemonic) continue;";
+  OS << "    if (Mnemonic != it->Mnemonic) continue;\n";
   
   // Emit check that the subclasses match.
   for (unsigned i = 0; i != MaxNumOperands; ++i) {