Use unique_ptr to hold AsmInfo,MRI,MII,STI

Reviewers: pcc, dblaikie

Reviewed By: dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D52389

llvm-svn: 342945
diff --git a/llvm/lib/Target/TargetMachine.cpp b/llvm/lib/Target/TargetMachine.cpp
index b3de6c1..39d5705 100644
--- a/llvm/lib/Target/TargetMachine.cpp
+++ b/llvm/lib/Target/TargetMachine.cpp
@@ -40,12 +40,7 @@
       RequireStructuredCFG(false), DefaultOptions(Options), Options(Options) {
 }
 
-TargetMachine::~TargetMachine() {
-  delete AsmInfo;
-  delete MRI;
-  delete MII;
-  delete STI;
-}
+TargetMachine::~TargetMachine() = default;
 
 bool TargetMachine::isPositionIndependent() const {
   return getRelocationModel() == Reloc::PIC_;