Subzero: Align spill locations to natural alignment.

src/IceTargetLowering.h

Index: src/IceTargetLowering.h
diff --git a/src/IceTargetLowering.h b/src/IceTargetLowering.h
index 91512a9fb47189ad7f322bb1d18e8c08816f076b..39e08def9b2c1a684d2437773f4ff76312e9ae80 100644
--- a/src/IceTargetLowering.h
+++ b/src/IceTargetLowering.h
@@ -134,7 +134,7 @@ public:
 
   virtual bool hasFramePointer() const { return false; }
   virtual SizeT getFrameOrStackReg() const = 0;
-  virtual size_t typeWidthInBytesOnStack(Type Ty) = 0;
+  virtual size_t typeWidthInBytesOnStack(Type Ty) const = 0;
   bool hasComputedFrame() const { return HasComputedFrame; }
   int32_t getStackAdjustment() const { return StackAdjustment; }
   void updateStackAdjustment(int32_t Offset) { StackAdjustment += Offset; }