Make LDV_FILL_SLOP use a forwards loop rather than a backwards loop

rts/LdvProfile.h

@@ -24,11 +24,11 @@ extern void LdvCensusKillAll ( void );
 // Invoked when: 
 //   1) Hp is incremented and exceeds HpLim (in Updates.hc).
 //   2) copypart() is called (in GC.c).
-#define LDV_FILL_SLOP(from, howManyBackwards)	\
+#define LDV_FILL_SLOP(from, howMany)	\
   if (era > 0) {				\
     int i;					\
-    for (i = 1;i <= (howManyBackwards); i++)	\
-      ((StgWord *)(from))[-i] = 0;		\
+    for (i = 0;i < (howMany); i++)	\
+      ((StgWord *)(from))[i] = 0;		\
   }
 
 // Informs the LDV profiler that closure c has just been evacuated.

rts/sm/Evac.c

@@ -212,7 +212,7 @@ spin:
     SET_EVACUAEE_FOR_LDV(from, size_to_reserve);
     // fill the slop
     if (size_to_reserve - size_to_copy > 0)
-	LDV_FILL_SLOP(to + size_to_reserve, (int)(size_to_reserve - size_to_copy));
+	LDV_FILL_SLOP(to + size_to_copy, (int)(size_to_reserve - size_to_copy));
 #endif
 
     return rtsTrue;