diff --git a/llvm/utils/TableGen/CodeGenDAGPatterns.cpp b/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
index d4c81c327abb..393076aa06a1 100644
--- a/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
+++ b/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
@@ -238,10 +238,14 @@ bool TypeSetByHwMode::operator==(const TypeSetByHwMode &VTS) const {
   return true;
 }
 
+raw_ostream &operator<<(raw_ostream &OS, const TypeSetByHwMode &T) {
+  T.writeToStream(OS);
+  return OS;
+}
+
 LLVM_DUMP_METHOD
 void TypeSetByHwMode::dump() const {
-  writeToStream(dbgs());
-  dbgs() << '\n';
+  dbgs() << *this << '\n';
 }
 
 bool TypeSetByHwMode::intersect(SetType &Out, const SetType &In) {
diff --git a/llvm/utils/TableGen/CodeGenDAGPatterns.h b/llvm/utils/TableGen/CodeGenDAGPatterns.h
index 37bfe022b4d1..f75e49a38218 100644
--- a/llvm/utils/TableGen/CodeGenDAGPatterns.h
+++ b/llvm/utils/TableGen/CodeGenDAGPatterns.h
@@ -240,6 +240,8 @@ private:
   bool intersect(SetType &Out, const SetType &In);
 };
 
+raw_ostream &operator<<(raw_ostream &OS, const TypeSetByHwMode &T);
+
 struct TypeInfer {
   TypeInfer(TreePattern &T) : TP(T), ForceMode(0) {}
 
diff --git a/llvm/utils/TableGen/CodeGenRegisters.cpp b/llvm/utils/TableGen/CodeGenRegisters.cpp
index f3b01eb5a946..a6b0a4beb8ea 100644
--- a/llvm/utils/TableGen/CodeGenRegisters.cpp
+++ b/llvm/utils/TableGen/CodeGenRegisters.cpp
@@ -836,7 +836,7 @@ bool CodeGenRegisterClass::contains(const CodeGenRegister *Reg) const {
 namespace llvm {
 
   raw_ostream &operator<<(raw_ostream &OS, const CodeGenRegisterClass::Key &K) {
-    OS << "{ " << K.RSI.getAsString();
+    OS << "{ " << K.RSI;
     for (const auto R : *K.Members)
       OS << ", " << R->getName();
     return OS << " }";
diff --git a/llvm/utils/TableGen/InfoByHwMode.cpp b/llvm/utils/TableGen/InfoByHwMode.cpp
index aee0dd6fa6a2..d4de490feeb2 100644
--- a/llvm/utils/TableGen/InfoByHwMode.cpp
+++ b/llvm/utils/TableGen/InfoByHwMode.cpp
@@ -76,34 +76,31 @@ StringRef ValueTypeByHwMode::getMVTName(MVT T) {
   return N;
 }
 
-std::string ValueTypeByHwMode::getAsString() const {
-  if (isSimple())
-    return getMVTName(getSimple());
+void ValueTypeByHwMode::writeToStream(raw_ostream &OS) const {
+  if (isSimple()) {
+    OS << getMVTName(getSimple());
+    return;
+  }
 
   std::vector<const PairType*> Pairs;
   for (const auto &P : Map)
     Pairs.push_back(&P);
   std::sort(Pairs.begin(), Pairs.end(), deref<std::less<PairType>>());
 
-  std::stringstream str;
-  str << '{';
+  OS << '{';
   for (unsigned i = 0, e = Pairs.size(); i != e; ++i) {
     const PairType *P = Pairs[i];
-    str << '(' << getModeName(P->first)
-        << ':' << getMVTName(P->second).str() << ')';
+    OS << '(' << getModeName(P->first)
+       << ':' << getMVTName(P->second).str() << ')';
     if (i != e-1)
-      str << ',';
+      OS << ',';
   }
-  str << '}';
-  return str.str();
+  OS << '}';
 }
 
 LLVM_DUMP_METHOD
 void ValueTypeByHwMode::dump() const {
-  dbgs() << "size=" << Map.size() << '\n';
-  for (const auto &P : Map)
-    dbgs() << "  " << P.first << " -> "
-           << llvm::getEnumName(P.second.SimpleTy) << '\n';
+  dbgs() << *this << '\n';
 }
 
 ValueTypeByHwMode llvm::getValueTypeByHwMode(Record *Rec,
@@ -136,11 +133,9 @@ bool RegSizeInfo::isSubClassOf(const RegSizeInfo &I) const {
          SpillSize <= I.SpillSize;
 }
 
-std::string RegSizeInfo::getAsString() const {
-  std::stringstream str;
-  str << "[R=" << RegSize << ",S=" << SpillSize
-      << ",A=" << SpillAlignment << ']';
-  return str.str();
+void RegSizeInfo::writeToStream(raw_ostream &OS) const {
+  OS << "[R=" << RegSize << ",S=" << SpillSize
+     << ",A=" << SpillAlignment << ']';
 }
 
 RegSizeInfoByHwMode::RegSizeInfoByHwMode(Record *R,
@@ -177,22 +172,35 @@ bool RegSizeInfoByHwMode::hasStricterSpillThan(const RegSizeInfoByHwMode &I)
          std::tie(B0.SpillSize, B0.SpillAlignment);
 }
 
-std::string RegSizeInfoByHwMode::getAsString() const {
+void RegSizeInfoByHwMode::writeToStream(raw_ostream &OS) const {
   typedef typename decltype(Map)::value_type PairType;
   std::vector<const PairType*> Pairs;
   for (const auto &P : Map)
     Pairs.push_back(&P);
   std::sort(Pairs.begin(), Pairs.end(), deref<std::less<PairType>>());
 
-  std::stringstream str;
-  str << '{';
+  OS << '{';
   for (unsigned i = 0, e = Pairs.size(); i != e; ++i) {
     const PairType *P = Pairs[i];
-    str << '(' << getModeName(P->first)
-        << ':' << P->second.getAsString() << ')';
+    OS << '(' << getModeName(P->first) << ':' << P->second << ')';
     if (i != e-1)
-      str << ',';
+      OS << ',';
   }
-  str << '}';
-  return str.str();
+  OS << '}';
 }
+
+raw_ostream &operator<<(raw_ostream &OS, const ValueTypeByHwMode &T) {
+  T.writeToStream(OS);
+  return OS;
+}
+
+raw_ostream &operator<<(raw_ostream &OS, const RegSizeInfo &T) {
+  T.writeToStream(OS);
+  return OS;
+}
+
+raw_ostream &operator<<(raw_ostream &OS, const RegSizeInfoByHwMode &T) {
+  T.writeToStream(OS);
+  return OS;
+}
+
diff --git a/llvm/utils/TableGen/InfoByHwMode.h b/llvm/utils/TableGen/InfoByHwMode.h
index 57640fc3025b..b2e217498888 100644
--- a/llvm/utils/TableGen/InfoByHwMode.h
+++ b/llvm/utils/TableGen/InfoByHwMode.h
@@ -27,6 +27,7 @@ namespace llvm {
 
 struct CodeGenHwModes;
 class Record;
+class raw_ostream;
 
 template <typename InfoT> struct InfoByHwMode;
 
@@ -130,7 +131,7 @@ struct ValueTypeByHwMode : public InfoByHwMode<MVT> {
   MVT &getOrCreateTypeForMode(unsigned Mode, MVT Type);
 
   static StringRef getMVTName(MVT T);
-  std::string getAsString() const;
+  void writeToStream(raw_ostream &OS) const;
   void dump() const;
 };
 
@@ -154,7 +155,7 @@ struct RegSizeInfo {
   }
 
   bool isSubClassOf(const RegSizeInfo &I) const;
-  std::string getAsString() const;
+  void writeToStream(raw_ostream &OS) const;
 };
 
 struct RegSizeInfoByHwMode : public InfoByHwMode<RegSizeInfo> {
@@ -169,8 +170,13 @@ struct RegSizeInfoByHwMode : public InfoByHwMode<RegSizeInfo> {
   bool isSubClassOf(const RegSizeInfoByHwMode &I) const;
   bool hasStricterSpillThan(const RegSizeInfoByHwMode &I) const;
 
-  std::string getAsString() const;
+  void writeToStream(raw_ostream &OS) const;
 };
+
+raw_ostream &operator<<(raw_ostream &OS, const ValueTypeByHwMode &T);
+raw_ostream &operator<<(raw_ostream &OS, const RegSizeInfo &T);
+raw_ostream &operator<<(raw_ostream &OS, const RegSizeInfoByHwMode &T);
+
 } // namespace llvm
 
 #endif // LLVM_UTILS_TABLEGEN_INFOBYHWMODE_H