/* -----------------------------------------------------------------------------
- * $Id: PrimOps.h,v 1.55 2000/05/28 20:22:08 panne Exp $
+ * $Id: PrimOps.h,v 1.56 2000/06/04 18:27:45 panne Exp $
*
* (c) The GHC Team, 1998-1999
*
(r) = RET_PRIM_STGCALL2(I_,mpz_cmp_si,&arg,i); \
}
-/* I think mp_limb_t must be the same size as StgInt for this to work
- * properly --SDM
- */
+/* NOTE: gcdIntzh and gcdIntegerIntzh work only for positive inputs! */
+
+/* mp_limb_t must be able to hold an StgInt for this to work properly */
#define gcdIntzh(r,a,b) \
-{ StgInt aa = a; \
- r = (aa) ? (b) ? \
- RET_STGCALL3(StgInt, mpn_gcd_1, (mp_limb_t *)(&aa), 1, (mp_limb_t)(b)) \
- : abs(aa) \
- : abs(b); \
+{ mp_limb_t aa = (mp_limb_t)(a); \
+ RET_STGCALL3(StgInt, mpn_gcd_1, (mp_limb_t *)(&aa), 1, (mp_limb_t)(b)); \
}
#define gcdIntegerIntzh(r,sa,a,b) \
minusInt(I# x) (I# y) = I# (x -# y)
timesInt(I# x) (I# y) = I# (x *# y)
quotInt (I# x) (I# y) = I# (quotInt# x y)
-remInt (I# x) (I# y) = I# (remInt# x y)
-gcdInt (I# a) (I# b) = I# (gcdInt# a b)
+remInt (I# x) (I# y) = I# (remInt# x y)
+
+gcdInt (I# 0#) (I# 0#) = error "PrelBase.gcdInt: gcd 0 0 is undefined"
+gcdInt a (I# 0#) = a
+gcdInt (I# 0#) b = b
+gcdInt (I# a) (I# b) = I# (gcdInt# (absInt a) (absInt b))
+ where absInt x = if x <# 0# then negateInt# x else x
negateInt :: Int -> Int
-negateInt (I# x) = I# (negateInt# x)
+negateInt (I# x) = I# (negateInt# x)
divInt, modInt :: Int -> Int -> Int
x `divInt` y
\begin{code}
gcdInteger :: Integer -> Integer -> Integer
+-- SUP: Do we really need the first two cases?
gcdInteger a@(S# (-2147483648#)) b = gcdInteger (toBig a) b
gcdInteger a b@(S# (-2147483648#)) = gcdInteger a (toBig b)
-gcdInteger (S# a) (S# b) = S# (gcdInt# a b)
-gcdInteger ia@(S# a) ib@(J# sb b)
+gcdInteger (S# a) (S# b) = case gcdInt (I# a) (I# b) of { I# c -> S# c }
+gcdInteger ia@(S# 0#) ib@(J# 0# _) = error "PrelNum.gcdInteger: gcd 0 0 is undefined"
+gcdInteger ia@(S# a) ib@(J# sb b)
| a ==# 0# = abs ib
| sb ==# 0# = abs ia
- | otherwise = S# (gcdIntegerInt# sb b a)
-gcdInteger ia@(J# sa a) ib@(S# b)
- | sa ==# 0# = abs ib
- | b ==# 0# = abs ia
- | otherwise = S# (gcdIntegerInt# sa a b)
+ | otherwise = S# (gcdIntegerInt# absSb b absA)
+ where absA = if a <# 0# then negateInt# a else a
+ absSb = if sb <# 0# then negateInt# sb else sb
+gcdInteger ia@(J# _ _) ib@(S# _) = gcdInteger ib ia
+gcdInteger (J# 0# _) (J# 0# _) = error "PrelNum.gcdInteger: gcd 0 0 is undefined"
gcdInteger (J# sa a) (J# sb b)
= case gcdInteger# sa a sb b of (# sg, g #) -> J# sg g