[TableGen] Adapt more places to getValueAsString now returning a StringRef instead of a std::string.

llvm-svn: 304347
diff --git a/llvm/utils/TableGen/FixedLenDecoderEmitter.cpp b/llvm/utils/TableGen/FixedLenDecoderEmitter.cpp
index e1aaecc..75fd730 100644
--- a/llvm/utils/TableGen/FixedLenDecoderEmitter.cpp
+++ b/llvm/utils/TableGen/FixedLenDecoderEmitter.cpp
@@ -1145,16 +1145,15 @@
     if (!Pred->getValue("AssemblerMatcherPredicate"))
       continue;
 
-    std::string P = Pred->getValueAsString("AssemblerCondString");
+    StringRef P = Pred->getValueAsString("AssemblerCondString");
 
-    if (!P.length())
+    if (P.empty())
       continue;
 
     if (!IsFirstEmission)
       o << " && ";
 
-    StringRef SR(P);
-    std::pair<StringRef, StringRef> pairs = SR.split(',');
+    std::pair<StringRef, StringRef> pairs = P.split(',');
     while (!pairs.second.empty()) {
       emitSinglePredicateMatch(o, pairs.first, Emitter->PredicateNamespace);
       o << " && ";
@@ -1174,9 +1173,9 @@
     if (!Pred->getValue("AssemblerMatcherPredicate"))
       continue;
 
-    std::string P = Pred->getValueAsString("AssemblerCondString");
+    StringRef P = Pred->getValueAsString("AssemblerCondString");
 
-    if (!P.length())
+    if (P.empty())
       continue;
 
     return true;
@@ -1744,7 +1743,7 @@
 
   // If the instruction has specified a custom decoding hook, use that instead
   // of trying to auto-generate the decoder.
-  std::string InstDecoder = Def.getValueAsString("DecoderMethod");
+  StringRef InstDecoder = Def.getValueAsString("DecoderMethod");
   if (InstDecoder != "") {
     bool HasCompleteInstDecoder = Def.getValueAsBit("hasCompleteDecoder");
     InsnOperands.push_back(OperandInfo(InstDecoder, HasCompleteInstDecoder));
@@ -2261,7 +2260,7 @@
         Def->getValueAsBit("isCodeGenOnly"))
       continue;
 
-    std::string DecoderNamespace = Def->getValueAsString("DecoderNamespace");
+    StringRef DecoderNamespace = Def->getValueAsString("DecoderNamespace");
 
     if (Size) {
       if (populateInstruction(Target, *Inst, i, Operands)) {