Simplify fix_sdescs by removing redundant check

yiannist · Mar 29, 2014 · 789c452 · 789c452
1 parent c28b0d5
commit 789c452
Showing 1 changed file with 8 additions and 12 deletions.
diff --git a/lib/hipe/llvm/hipe_llvm_main.erl b/lib/hipe/llvm/hipe_llvm_main.erl
@@ -427,25 +427,21 @@ find_offsets([{Off,Arity}|Rest], Offsets, Acc) ->
   [I | RestOffsets] = lists:dropwhile(fun (Y) -> Y<Off end, Offsets),
   find_offsets(Rest, RestOffsets, [{I, Arity}|Acc]).
 
-%% The function below corrects the arity of calls, that are identified
+%% The function below corrects the stack descriptors of calls with arguments
-%% by offset, in the stack descriptors.
+%% that are passed on the stack (more the NR_ARG_REGS) by subtracting the
+%% number of stacked arguments from the frame size and from the offset of the
+%% roots.
 fix_sdescs([], SDescs) -> SDescs;
 fix_sdescs([{Offset, Arity} | Rest], SDescs) ->
   case lists:keyfind(Offset, 2, SDescs) of
     false ->
       fix_sdescs(Rest, SDescs);
-    {?SDESC, Offset, SDesc} ->
+    {?SDESC, Offset, {ExnHandler, FrameSize, StkArity, Roots}} ->
-      {ExnHandler, FrameSize, StkArity, Roots} = SDesc,
       FixedRoots = [X - Arity || X <- tuple_to_list(Roots)],
-      NewRoots =
+      FixedSDesc =
-        case FixedRoots of
+        {?SDESC, Offset, {ExnHandler, FrameSize - Arity, StkArity, FixedRoots}},
-          [H|_] when H >= 0 -> list_to_tuple(FixedRoots);
-          _ -> Roots
-        end,
-      NewSDesc =
-        {?SDESC, Offset, {ExnHandler, FrameSize - Arity, StkArity, NewRoots}},
       RestSDescs = lists:keydelete(Offset, 2, SDescs),
-      fix_sdescs(Rest, [NewSDesc | RestSDescs])
+      fix_sdescs(Rest, [FixedSDesc | RestSDescs])
   end.