Enable Local CSE by default

src/IceDefs.h

Index: src/IceDefs.h
diff --git a/src/IceDefs.h b/src/IceDefs.h
index 2c09ba9941f091b1388bcba420787a1a178f7b43..edd63fc3aadea06864236cd2e4552b12d813388a 100644
--- a/src/IceDefs.h
+++ b/src/IceDefs.h
@@ -308,6 +308,12 @@ enum LivenessMode {
   Liveness_Intervals
 };
 
+enum class LCSEOptions {

[Jim Stichnoth, 2016/07/29 14:49:02]

Bikeshed: For consistency with these other enums, I would use "enum" instead of
"enum class", and then pick a "unique" short prefix for the enum values.  E.g.:

enum LcseOptions {
  LCSE_Disabled,
  LCSE_EnabledSSA,
  LCSE_EnabledNoSSA
};

I agree though that "enum class" is a cleaner way to deal with the global
namespace pollution.  This is probably a legacy of pre-C++11 code.

[manasijm, 2016/08/01 17:39:24]

Done.

+  Disabled,
+  EnabledSSA,  // Default Mode, assumes SSA.
+  EnabledNoSSA // Does not assume SSA, to be enabled if CSE is done later.
+};
+
 enum RegAllocKind {
   RAK_Unknown,
   RAK_Global,       /// full, global register allocation