[shortcut fetching of a constant value
John Meacham <john@repetae.net>**20060124081305] hunk ./Grin/Simplify.hs 42
+at_OptSimplifyConstFetch  = toAtom "Optimize.simplify.const-fetch"
hunk ./Grin/Simplify.hs 81
+    gs (Fetch (Const n)) = do
+        lift $ tick stats at_OptSimplifyConstFetch
+        gs (Return n)