Introduction of improved switch lowering.

src/IceTargetLoweringMIPS32.h

Index: src/IceTargetLoweringMIPS32.h
diff --git a/src/IceTargetLoweringMIPS32.h b/src/IceTargetLoweringMIPS32.h
index a72c8dbfb388658bfaf39a67aea6cdbe4fabe1fd..d9629229eeee8eb43ce8ca01eb10ed7a5aae39a2 100644
--- a/src/IceTargetLoweringMIPS32.h
+++ b/src/IceTargetLoweringMIPS32.h
@@ -53,6 +53,10 @@ public:
     // i8, and i16 are rounded up to 4 bytes.
     return (typeWidthInBytes(Ty) + 3) & ~3;
   }
+
+  // TODO(ascull): what is the best size of ARM?
+  SizeT getMinJumpTableSize() const override { return 3; }
+
   void emitVariable(const Variable *Var) const override;
 
   const char *getConstantPrefix() const final { return ""; }