[tablegen] Avoid creating temporary strings

If a method / function returns a StringRef but the 
variable is of type const std::string& a temporary string is
created (StringRef has a cast operator to std::string),
which is a suboptimal behavior.

Differential revision: https://reviews.llvm.org/D34994

Test plan: make check-all

llvm-svn: 307195

1 files changed, 1 insertions, 3 deletions

diff --git a/llvm/utils/TableGen/FixedLenDecoderEmitter.cpp b/llvm/utils/TableGen/FixedLenDecoderEmitter.cpp
index 75fd73082b9..03930d7132d 100644
--- a/llvm/utils/TableGen/FixedLenDecoderEmitter.cpp
+++ b/llvm/utils/TableGen/FixedLenDecoderEmitter.cpp
@@ -1691,9 +1691,7 @@ void FilterChooser::emitTableEntries(DecoderTableInfo &TableInfo) const {
   dumpStack(errs(), "\t\t");
 
   for (unsigned i = 0; i < Opcodes.size(); ++i) {
-    const std::string &Name = nameWithID(Opcodes[i]);
-
-    errs() << '\t' << Name << " ";
+    errs() << '\t' << nameWithID(Opcodes[i]) << " ";
     dumpBits(errs(),
              getBitsField(*AllInstructions[Opcodes[i]]->TheDef, "Inst"));
     errs() << '\n';