Enable proper constant island alignment by default.

The code size increase is tiny (< 0.05%) because so little code uses
16-byte constant pool entries.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146690 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMConstantIslandPass.cpp b/lib/Target/ARM/ARMConstantIslandPass.cpp
index f710cfa..2039d41 100644
--- a/lib/Target/ARM/ARMConstantIslandPass.cpp
+++ b/lib/Target/ARM/ARMConstantIslandPass.cpp
@@ -53,7 +53,7 @@
           cl::desc("Adjust basic block layout to better use TB[BH]"));
 
 static cl::opt<bool>
-AlignConstantIslands("arm-align-constant-islands", cl::Hidden,
+AlignConstantIslands("arm-align-constant-islands", cl::Hidden, cl::init(true),
           cl::desc("Align constant islands in code"));
 
 /// UnknownPadding - Return the worst case padding that could result from