[ARM64] Fix a heap-use-after-free spotted by ASan.

StringRef::lower() returns a std::string. Better yet, we can now stop
thinking about what it returns and write 'auto'. It does the right
thing. =]

llvm-svn: 205135

diff --git a/llvm/lib/Target/ARM64/AsmParser/ARM64AsmParser.cpp b/llvm/lib/Target/ARM64/AsmParser/ARM64AsmParser.cpp
index e72189e766a0244ff59e93322adf7b07abbd773e..705d192356e029ef36991219c6a1fbf80209ef41 100644 (file)
--- a/llvm/lib/Target/ARM64/AsmParser/ARM64AsmParser.cpp
+++ b/llvm/lib/Target/ARM64/AsmParser/ARM64AsmParser.cpp
@@ -2653,7 +2653,7 @@ ARM64AsmParser::tryParseSystemRegister(OperandVector &Operands) {
   if (Tok.isNot(AsmToken::Identifier))
     return MatchOperand_NoMatch;
 
-  StringRef ID = Tok.getString().lower();
+  auto ID = Tok.getString().lower();
   ARM64SYS::SystemRegister Reg =
       StringSwitch<ARM64SYS::SystemRegister>(ID)
           .Case("spsr_el1", ARM64SYS::SPSR_svc)