Add tests for bitshift PrelRules

testsuite/tests/ghc-regress/simplCore/should_run/all.T

@@ -15,3 +15,4 @@ test('simplrun003', normal, compile_and_run, [''])
 test('simplrun004', normal, compile_and_run, [''])
 test('simplrun005', normal, compile_and_run, [''])
 test('simplrun006', normal, compile_and_run, [''])
+test('simplrun007', normal, compile_and_run, [''])

testsuite/tests/ghc-regress/simplCore/should_run/simplrun007.hs

+{-# OPTIONS_GHC -fglasgow-exts #-}
+
+-- Actually, this exercises prelude/PrelRules, but this is the closest
+-- place I could find to put it...
+
+import GHC.Exts
+import Numeric
+import Data.Bits
+
+main = do phex (I# (uncheckedIShiftL#  (negateInt# 5#) 2#))
+          phex (I# (uncheckedIShiftRA# (negateInt# 5#) 1#))
+          phex (I# (uncheckedIShiftRL# (negateInt# 5#) 1#))
+          phex (W# (uncheckedShiftL#   (int2Word# (negateInt# 5#)) 2#))
+          phex (W# (uncheckedShiftRL#  (int2Word# (negateInt# 5#)) 1#))
+
+phex x = putStrLn (showSigned (\x -> ("0x"++) . showHex x) 0 x "")
+
+{- Too wordsize-dependant
+phex x = putStrLn (hex x)
+hex x = "0x" ++ [onedigit (fromIntegral ((x `shiftR` (i*4)) .&. 0xF))
+                 | i <- [digits-1,digits-2..0]]
+    where
+    digits = bitSize x `div` 4
+    onedigit n = "0123456789abcdef" !! n
+-}
+
+

testsuite/tests/ghc-regress/simplCore/should_run/simplrun007.stdout

+-0x14
+-0x3
+0x7ffffffd
+0xffffffec
+0x7ffffffd