[TableGen] Make Record::getValueAsString and getValueAsListOfStrings return StringRefs instead of std::string

Internally both these methods just return the result of getValue on either a StringInit or a CodeInit object. In both cases this returns a StringRef pointing to a string allocated in the BumpPtrAllocator so its not going anywhere. So we can just pass that StringRef along.

This is a fairly naive patch that targets just the build failures caused by this change. There's additional work that can be done to avoid creating std::string at call sites that still think getValueAsString returns a std::string. I'll try to clean those up in future patches.

Differential Revision: https://reviews.llvm.org/D33710

llvm-svn: 304325

6 files changed, 32 insertions, 24 deletions

diff --git a/llvm/utils/TableGen/AsmMatcherEmitter.cpp b/llvm/utils/TableGen/AsmMatcherEmitter.cpp
index 264175ae967..3814ce8db6a 100644
--- a/llvm/utils/TableGen/AsmMatcherEmitter.cpp
+++ b/llvm/utils/TableGen/AsmMatcherEmitter.cpp
@@ -2486,14 +2486,18 @@ static void emitMnemonicAliasVariant(raw_ostream &OS,const AsmMatcherInfo &Info,
       if (!MatchCode.empty())
         MatchCode += "else ";
       MatchCode += "if ((Features & " + FeatureMask + ") == "+FeatureMask+")\n";
-      MatchCode += "  Mnemonic = \"" +R->getValueAsString("ToMnemonic")+"\";\n";
+      MatchCode += "  Mnemonic = \"";
+      MatchCode += R->getValueAsString("ToMnemonic");
+      MatchCode += "\";\n";
     }
 
     if (AliasWithNoPredicate != -1) {
       Record *R = ToVec[AliasWithNoPredicate];
       if (!MatchCode.empty())
         MatchCode += "else\n  ";
-      MatchCode += "Mnemonic = \"" + R->getValueAsString("ToMnemonic")+"\";\n";
+      MatchCode += "Mnemonic = \"";
+      MatchCode += R->getValueAsString("ToMnemonic");
+      MatchCode += "\";\n";
     }
 
     MatchCode += "return;";
diff --git a/llvm/utils/TableGen/AsmWriterEmitter.cpp b/llvm/utils/TableGen/AsmWriterEmitter.cpp
index 40b7857ab99..4b06e9e247f 100644
--- a/llvm/utils/TableGen/AsmWriterEmitter.cpp
+++ b/llvm/utils/TableGen/AsmWriterEmitter.cpp
@@ -523,7 +523,7 @@ emitRegisterNameString(raw_ostream &O, StringRef AltName,
       // If the register has an alternate name for this index, use it.
       // Otherwise, leave it empty as an error flag.
       if (Idx < e) {
-        std::vector<std::string> AltNames =
+        std::vector<StringRef> AltNames =
           Reg.TheDef->getValueAsListOfStrings("AltNames");
         if (AltNames.size() <= Idx)
           PrintFatalError(Reg.TheDef->getLoc(),
diff --git a/llvm/utils/TableGen/CodeEmitterGen.cpp b/llvm/utils/TableGen/CodeEmitterGen.cpp
index 565235d8214..26b007250eb 100644
--- a/llvm/utils/TableGen/CodeEmitterGen.cpp
+++ b/llvm/utils/TableGen/CodeEmitterGen.cpp
@@ -278,11 +278,11 @@ void CodeEmitterGen::run(raw_ostream &o) {
     if (R->getValueAsString("Namespace") == "TargetOpcode" ||
         R->getValueAsBit("isPseudo"))
       continue;
-    const std::string &InstName = R->getValueAsString("Namespace") + "::"
-      + R->getName().str();
+    std::string InstName =
+        (R->getValueAsString("Namespace") + "::" + R->getName()).str();
     std::string Case = getInstructionCase(R, Target);
 
-    CaseMap[Case].push_back(InstName);
+    CaseMap[Case].push_back(std::move(InstName));
   }
 
   // Emit initial function code
diff --git a/llvm/utils/TableGen/CodeGenDAGPatterns.cpp b/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
index ef2cb4208ea..241fabf8631 100644
--- a/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
+++ b/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
@@ -893,7 +893,9 @@ std::string PatternToMatch::getPredicateCheck() const {
   for (Record *Pred : PredicateRecs) {
     if (!PredicateCheck.empty())
       PredicateCheck += " && ";
-    PredicateCheck += "(" + Pred->getValueAsString("CondString") + ")";
+    PredicateCheck += "(";
+    PredicateCheck += Pred->getValueAsString("CondString");
+    PredicateCheck += ")";
   }
 
   return PredicateCheck.str();
diff --git a/llvm/utils/TableGen/GlobalISelEmitter.cpp b/llvm/utils/TableGen/GlobalISelEmitter.cpp
index e0303b7b1ab..88ded1f25ff 100644
--- a/llvm/utils/TableGen/GlobalISelEmitter.cpp
+++ b/llvm/utils/TableGen/GlobalISelEmitter.cpp
@@ -118,7 +118,7 @@ static std::string explainPredicates(const TreePatternNode *N) {
 
 std::string explainOperator(Record *Operator) {
   if (Operator->isSubClassOf("SDNode"))
-    return " (" + Operator->getValueAsString("Opcode") + ")";
+    return (" (" + Operator->getValueAsString("Opcode") + ")").str();
 
   if (Operator->isSubClassOf("Intrinsic"))
     return (" (Operator is an Intrinsic, " + Operator->getName() + ")").str();
diff --git a/llvm/utils/TableGen/OptParserEmitter.cpp b/llvm/utils/TableGen/OptParserEmitter.cpp
index c1b5e651032..04e6537f3d1 100644
--- a/llvm/utils/TableGen/OptParserEmitter.cpp
+++ b/llvm/utils/TableGen/OptParserEmitter.cpp
@@ -21,6 +21,8 @@ using namespace llvm;
 
 // Ordering on Info. The logic should match with the consumer-side function in
 // llvm/Option/OptTable.h.
+// FIXME: Mmake this take StringRefs instead of null terminated strings to
+// simplify callers.
 static int StrCmpOptionName(const char *A, const char *B) {
   const char *X = A, *Y = B;
   char a = tolower(*A), b = tolower(*B);
@@ -53,22 +55,22 @@ static int CompareOptionRecords(Record *const *Av, Record *const *Bv) {
 
   // Compare options by name, unless they are sentinels.
   if (!ASent)
-    if (int Cmp = StrCmpOptionName(A->getValueAsString("Name").c_str(),
-                                   B->getValueAsString("Name").c_str()))
+    if (int Cmp = StrCmpOptionName(A->getValueAsString("Name").str().c_str(),
+                                   B->getValueAsString("Name").str().c_str()))
       return Cmp;
 
   if (!ASent) {
-    std::vector<std::string> APrefixes = A->getValueAsListOfStrings("Prefixes");
-    std::vector<std::string> BPrefixes = B->getValueAsListOfStrings("Prefixes");
-
-    for (std::vector<std::string>::const_iterator APre = APrefixes.begin(),
-                                                  AEPre = APrefixes.end(),
-                                                  BPre = BPrefixes.begin(),
-                                                  BEPre = BPrefixes.end();
-                                                  APre != AEPre &&
-                                                  BPre != BEPre;
-                                                  ++APre, ++BPre) {
-      if (int Cmp = StrCmpOptionName(APre->c_str(), BPre->c_str()))
+    std::vector<StringRef> APrefixes = A->getValueAsListOfStrings("Prefixes");
+    std::vector<StringRef> BPrefixes = B->getValueAsListOfStrings("Prefixes");
+
+    for (std::vector<StringRef>::const_iterator APre = APrefixes.begin(),
+                                                AEPre = APrefixes.end(),
+                                                BPre = BPrefixes.begin(),
+                                                BEPre = BPrefixes.end();
+                                                APre != AEPre &&
+                                                BPre != BEPre;
+                                                ++APre, ++BPre) {
+      if (int Cmp = StrCmpOptionName(APre->str().c_str(), BPre->str().c_str()))
         return Cmp;
     }
   }
@@ -122,7 +124,7 @@ void EmitOptParser(RecordKeeper &Records, raw_ostream &OS) {
   unsigned CurPrefix = 0;
   for (unsigned i = 0, e = Opts.size(); i != e; ++i) {
     const Record &R = *Opts[i];
-    std::vector<std::string> prf = R.getValueAsListOfStrings("Prefixes");
+    std::vector<StringRef> prf = R.getValueAsListOfStrings("Prefixes");
     PrefixKeyT prfkey(prf.begin(), prf.end());
     unsigned NewPrefix = CurPrefix + 1;
     if (Prefixes.insert(std::make_pair(prfkey, (Twine("prefix_") +
@@ -207,7 +209,7 @@ void EmitOptParser(RecordKeeper &Records, raw_ostream &OS) {
     OS << "OPTION(";
 
     // The option prefix;
-    std::vector<std::string> prf = R.getValueAsListOfStrings("Prefixes");
+    std::vector<StringRef> prf = R.getValueAsListOfStrings("Prefixes");
     OS << Prefixes[PrefixKeyT(prf.begin(), prf.end())] << ", ";
 
     // The option string.
@@ -240,7 +242,7 @@ void EmitOptParser(RecordKeeper &Records, raw_ostream &OS) {
     // would become "foo\0bar\0". Note that the compiler adds an implicit
     // terminating \0 at the end.
     OS << ", ";
-    std::vector<std::string> AliasArgs = R.getValueAsListOfStrings("AliasArgs");
+    std::vector<StringRef> AliasArgs = R.getValueAsListOfStrings("AliasArgs");
     if (AliasArgs.size() == 0) {
       OS << "nullptr";
     } else {