Add optimize-for-size knob.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48793 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/TargetMachine.cpp b/lib/Target/TargetMachine.cpp
index 15164ca2..b9a6878 100644
--- a/lib/Target/TargetMachine.cpp
+++ b/lib/Target/TargetMachine.cpp
@@ -34,6 +34,7 @@
   Reloc::Model RelocationModel;
   CodeModel::Model CMModel;
   bool PerformTailCallOpt;
+  bool OptimizeForSize;
 }
 namespace {
   cl::opt<bool, true> PrintCode("print-machineinstrs",
@@ -123,6 +124,11 @@
                            cl::desc("Turn on tail call optimization."),
                            cl::location(PerformTailCallOpt),
                            cl::init(false));
+  cl::opt<bool, true>
+  EnableOptimizeForSize("optimizeforsize",
+                        cl::desc("Optimize for size."),
+                           cl::location(OptimizeForSize),
+                           cl::init(false));
 }
 
 //---------------------------------------------------------------------------