[project @ 1997-11-20 16:45:38 by simonm]

* fix minBound::Int32 in view of the fact that minBound::Int is wrong.
* fix shift direction (it was reversed)
* fix complement to be a 1's complement instead of 2's complement

diff --git a/ghc/lib/glaExts/Int.lhs b/ghc/lib/glaExts/Int.lhs
index b539bae..1ef116f 100644 (file)
--- a/ghc/lib/glaExts/Int.lhs
+++ b/ghc/lib/glaExts/Int.lhs
@@ -244,9 +244,11 @@ instance Num Int32 where
     fromInteger   = to . fromInteger
     fromInt       = to
 
-instance Bounded Int32 where
-    minBound = to minBound
-    maxBound = to maxBound
+-- ToDo: remove LitLit when minBound::Int is fixed (currently it's one
+-- too high, and doesn't allow the correct minBound to be defined here).
+instance Bounded Int32 where 
+    minBound = I32 ``0x80000000''
+    maxBound = I32   0x7fffffff
 
 instance Real Int32 where
     toRational x = toInteger x % 1
@@ -284,12 +286,12 @@ instance Bits Int32 where
   x .&. y              = to (binop (wordop and#) x y)
   x .|. y              = to (binop (wordop or# ) x y)
   x `xor` y            = to (binop (wordop xor#) x y)
-  complement x         = (x `xor` maxBound) + 1
+  complement x         = x `xor` -1
   shift (I32 (I# x)) i@(I# i#)
-       | i > 0     = I32 (I# (iShiftRL# x i#))
-       | otherwise = I32 (I# (iShiftL# x i#))
+       | i > 0     = I32 (I# (iShiftL# x i#))
+       | otherwise = I32 (I# (iShiftRA# x i#))
 --  rotate        
-  bit i                = 1 `shift` -i
+  bit i                = 1 `shift` i
   setBit x i    = x .|. bit i
   clearBit x i  = x .&. complement (bit i)
   complementBit x i = x `xor` bit i