X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=includes%2FStg.h;h=5cd3701c0fae311128ec7d4ba0762d8f8acc258c;hb=807c4b5f58800a069092fc82fbb48a04f4e6cacd;hp=a63b7ec2d6f43d980375f2fd9b90c9238c7a3620;hpb=0065d5ab628975892cea1ec7303f968c3338cbe1;p=ghc-hetmet.git

diff --git a/includes/Stg.h b/includes/Stg.h
index a63b7ec..5cd3701 100644
--- a/includes/Stg.h
+++ b/includes/Stg.h
@@ -127,8 +127,8 @@ typedef StgWord64       LW_;
 #define EF_(f)		extern F_ f(void)
 
 typedef StgWord StgWordArray[];
-#define EI_             extern StgWordArray
-#define II_             static StgWordArray
+#define EI_(X)          extern StgWordArray (X) GNU_ATTRIBUTE(aligned (8))
+#define II_(X)          static StgWordArray (X) GNU_ATTRIBUTE(aligned (8))
 
 /* -----------------------------------------------------------------------------
    Tail calls
@@ -442,7 +442,9 @@ typedef union {
 
 /* Approximate version when we don't have long arithmetic (on 64-bit archs) */
 
-#define HALF_POS_INT  (((I_)1) << (BITS_IN (I_) / 2))
+/* If we have n-bit words then we have n-1 bits after accounting for the
+ * sign bit, so we can fit the result of multiplying 2 (n-1)/2-bit numbers */
+#define HALF_POS_INT  (((I_)1) << ((BITS_IN (I_) - 1) / 2))
 #define HALF_NEG_INT  (-HALF_POS_INT)
 
 #define mulIntMayOflo(a,b)			\