diff options
Diffstat (limited to 'lib/hipe/flow/cfg.inc')
| -rw-r--r-- | lib/hipe/flow/cfg.inc | 51 |
1 files changed, 46 insertions, 5 deletions
diff --git a/lib/hipe/flow/cfg.inc b/lib/hipe/flow/cfg.inc index a18bfbc526..cb5f397f64 100644 --- a/lib/hipe/flow/cfg.inc +++ b/lib/hipe/flow/cfg.inc @@ -32,6 +32,8 @@ %% bb(CFG, Label) - returns the basic block named 'Label' from the CFG. %% bb_add(CFG, Label, NewBB) - makes NewBB the basic block associated %% with Label. +%% map_bbs(Fun, CFG) - map over all code without changing control flow. +%% fold_bbs(Fun, Acc, CFG) - fold over the basic blocks in a CFG. %% succ(Map, Label) - returns a list of successors of basic block 'Label'. %% pred(Map, Label) - returns the predecessors of basic block 'Label'. %% fallthrough(CFG, Label) - returns fall-through successor of basic @@ -89,6 +91,7 @@ -define(BREADTH_ORDER,true). % for linear scan -define(PARAMS_NEEDED,true). -define(START_LABEL_UPDATE_NEEDED,true). +-define(MAP_FOLD_NEEDED,true). -endif. %%===================================================================== @@ -307,11 +310,7 @@ redirect_phis([I|Rest], OldPred, NewPred, Acc) -> %% @doc Adds a new basic block to a CFG (or updates an existing block). bb_add(CFG, Label, NewBB) -> %% Asserting that the NewBB is a legal basic block - Last = hipe_bb:last(NewBB), - case is_branch(Last) of - true -> ok; - false -> throw({?MODULE, {"Basic block ends without branch", Last}}) - end, + Last = assert_bb(NewBB), %% The order of the elements from branch_successors/1 is %% significant. It determines the basic block order when the CFG is %% converted to linear form. That order may have been tuned for @@ -339,6 +338,48 @@ bb_add(CFG, Label, NewBB) -> HT2, OldSucc -- Succ), CFG#cfg{table = HT3}. +-ifdef(MAP_FOLD_NEEDED). +-spec map_bbs(fun((cfg_lbl(), hipe_bb:bb()) -> hipe_bb:bb()), cfg()) -> cfg(). +%% @doc Map over the code in a CFG without changing any control flow. +map_bbs(Fun, CFG = #cfg{table=HT0}) -> + HT = gb_trees:map( + fun(Lbl, {OldBB, OldSucc, OldPred}) -> + NewBB = Fun(Lbl, OldBB), + %% Assert preconditions + NewLast = assert_bb(NewBB), + OldSucc = remove_duplicates(branch_successors(NewLast)), + {NewBB, OldSucc, OldPred} + end, HT0), + CFG#cfg{table=HT}. + +-spec fold_bbs(fun((cfg_lbl(), hipe_bb:bb(), Acc) -> Acc), Acc, cfg()) -> Acc. +%% @doc Fold over the basic blocks in a CFG in unspecified order. +fold_bbs(Fun, InitAcc, #cfg{table=HT}) -> + gb_trees_fold(fun(Lbl, {BB, _, _}, Acc) -> Fun(Lbl, BB, Acc) end, + InitAcc, HT). + +gb_trees_fold(Fun, InitAcc, Tree) -> + gb_trees_fold_1(Fun, InitAcc, gb_trees:iterator(Tree)). + +gb_trees_fold_1(Fun, InitAcc, Iter0) -> + case gb_trees:next(Iter0) of + none -> InitAcc; + {Key, Value, Iter} -> + gb_trees_fold_1(Fun, Fun(Key, Value, InitAcc), Iter) + end. +-endif. % MAP_FOLD_NEEDED + +assert_bb(BB) -> + assert_bb_is(hipe_bb:code(BB)). + +assert_bb_is([Last]) -> + true = is_branch(Last), + Last; +assert_bb_is([I|Is]) -> + false = is_branch(I), + false = is_label(I), + assert_bb_is(Is). + remove_pred(HT, FromL, PredL) -> case gb_trees:lookup(FromL, HT) of {value, {Block, Succ, Preds}} -> |