Minor cleanups and bug fixes of the compiler

lib/compiler/src/beam_a.erl

@@ -59,6 +59,9 @@ rename_instrs([{test,is_eq_exact,_,[Dst,Src]}=Test,
 rename_instrs([{test,is_eq_exact,_,[Same,Same]}|Is]) ->
     %% Same literal or same register. Will always succeed.
     rename_instrs(Is);
+rename_instrs([{loop_rec,{f,Fail},{x,0}},{loop_rec_end,_},{label,Fail}|Is]) ->
+    %% This instruction sequence does nothing.
+    rename_instrs(Is);
 rename_instrs([{apply_last,A,N}|Is]) ->
     [{apply,A},{deallocate,N},return|rename_instrs(Is)];
 rename_instrs([{call_last,A,F,N}|Is]) ->

lib/compiler/src/beam_block.erl

@@ -49,9 +49,6 @@ function({function,Name,Arity,CLabel,Is0}) ->
 blockify(Is) ->
     blockify(Is, []).
 
-blockify([{loop_rec,{f,Fail},{x,0}},{loop_rec_end,_Lbl},{label,Fail}|Is], Acc) ->
-    %% Useless instruction sequence.
-    blockify(Is, Acc);
 blockify([I|Is0]=IsAll, Acc) ->
     case collect(I) of
 	error -> blockify(Is0, [I|Acc]);

lib/compiler/src/beam_clean.erl

@@ -23,17 +23,15 @@
 
 -export([module/2]).
 -export([clean_labels/1]).
--import(lists, [foldl/3]).
 
 -spec module(beam_utils:module_code(), [compile:option()]) ->
                     {'ok',beam_utils:module_code()}.
 
 module({Mod,Exp,Attr,Fs0,_}, Opts) ->
     Order = [Lbl || {function,_,_,Lbl,_} <- Fs0],
-    All = foldl(fun({function,_,_,Lbl,_}=Func,D) -> dict:store(Lbl, Func, D) end,
-		dict:new(), Fs0),
+    All = maps:from_list([{Lbl,Func} || {function,_,_,Lbl,_}=Func <- Fs0]),
     WorkList = rootset(Fs0, Exp, Attr),
-    Used = find_all_used(WorkList, All, sets:from_list(WorkList)),
+    Used = find_all_used(WorkList, All, cerl_sets:from_list(WorkList)),
     Fs1 = remove_unused(Order, Used, All),
     {Fs2,Lc} = clean_labels(Fs1),
     Fs = maybe_remove_lines(Fs2, Opts),
@@ -55,16 +53,16 @@ rootset(Fs, Root0, Attr) ->
 %% Remove the unused functions.
 
 remove_unused([F|Fs], Used, All) ->
-    case sets:is_element(F, Used) of
+    case cerl_sets:is_element(F, Used) of
 	false -> remove_unused(Fs, Used, All);
-	true -> [dict:fetch(F, All)|remove_unused(Fs, Used, All)]
+	true -> [map_get(F, All)|remove_unused(Fs, Used, All)]
     end;
 remove_unused([], _, _) -> [].
-	    
+
 %% Find all used functions.
 
 find_all_used([F|Fs0], All, Used0) ->
-    {function,_,_,_,Code} = dict:fetch(F, All),
+    {function,_,_,_,Code} = map_get(F, All),
     {Fs,Used} = update_work_list(Code, {Fs0,Used0}),
     find_all_used(Fs, All, Used);
 find_all_used([], _All, Used) -> Used.
@@ -78,9 +76,9 @@ update_work_list([_|Is], Sets) ->
 update_work_list([], Sets) -> Sets.
 
 add_to_work_list(F, {Fs,Used}=Sets) ->
-    case sets:is_element(F, Used) of
+    case cerl_sets:is_element(F, Used) of
 	true -> Sets;
-	false -> {[F|Fs],sets:add_element(F, Used)}
+	false -> {[F|Fs],cerl_sets:add_element(F, Used)}
     end.
 
 

lib/compiler/src/beam_flatten.erl

@@ -32,8 +32,7 @@ module({Mod,Exp,Attr,Fs,Lc}, _Opt) ->
     {ok,{Mod,Exp,Attr,[function(F) || F <- Fs],Lc}}.
 
 function({function,Name,Arity,CLabel,Is0}) ->
-    Is1 = block(Is0),
-    Is = opt(Is1),
+    Is = block(Is0),
     {function,Name,Arity,CLabel,Is}.
 
 block(Is) ->
@@ -43,21 +42,12 @@ block([{block,Is0}|Is1], Acc) -> block(Is1, norm_block(Is0, Acc));
 block([I|Is], Acc) -> block(Is, [I|Acc]);
 block([], Acc) -> reverse(Acc).
 
-norm_block([{set,[],[],{alloc,R,{_,nostack,_,_}=Alloc}}|Is], Acc0) ->
-    case insert_alloc_in_bs_init(Acc0, Alloc) of
-	impossible ->
-	    norm_block(Is, reverse(norm_allocate(Alloc, R), Acc0));
-	Acc ->
-	    norm_block(Is, Acc)
-    end;
 norm_block([{set,[],[],{alloc,R,Alloc}}|Is], Acc0) ->
     norm_block(Is, reverse(norm_allocate(Alloc, R), Acc0));
-norm_block([{set,[D1],[S],get_hd},{set,[D2],[S],get_tl}|Is], Acc) ->
-    I = {get_list,S,D1,D2},
-    norm_block(Is, [I|Acc]);
-norm_block([I|Is], Acc) -> norm_block(Is, [norm(I)|Acc]);
+norm_block([I|Is], Acc) ->
+    norm_block(Is, [norm(I)|Acc]);
 norm_block([], Acc) -> Acc.
-    
+
 norm({set,[D],As,{bif,N,F}})      -> {bif,N,F,As,D};
 norm({set,[D],As,{alloc,R,{gc_bif,N,F}}}) -> {gc_bif,N,F,R,As,D};
 norm({set,[D],[],init})           -> {init,D};
@@ -91,57 +81,3 @@ norm_allocate({nozero,Ns,0,Inits}, Regs) ->
     [{allocate,Ns,Regs}|Inits];
 norm_allocate({nozero,Ns,Nh,Inits}, Regs) ->
     [{allocate_heap,Ns,Nh,Regs}|Inits].
-
-%% insert_alloc_in_bs_init(ReverseInstructionStream, AllocationInfo) ->
-%%                                  impossible | ReverseInstructionStream'
-%%   A bs_init/6 instruction should not be followed by a test heap instruction.
-%%   Given the AllocationInfo from a test heap instruction, merge the
-%%   allocation amounts into the previous bs_init/6 instruction (if any).
-%%
-insert_alloc_in_bs_init([{bs_put,_,_,_}=I|Is], Alloc) ->
-    %% The instruction sequence ends with an bs_put/4 instruction.
-    %% We'll need to search backwards for the bs_init/6 instruction.
-    insert_alloc_1(Is, Alloc, [I]);
-insert_alloc_in_bs_init(_, _) -> impossible.
-
-insert_alloc_1([{bs_init=Op,Fail,Info0,Live,Ss,Dst}|Is],
-	       {_,nostack,Ws2,[]}, Acc) when is_integer(Live) ->
-    %% The number of extra heap words is always in the second position
-    %% in the Info tuple.
-    Ws1 = element(2, Info0),
-    Al = beam_utils:combine_heap_needs(Ws1, Ws2),
-    Info = setelement(2, Info0, Al),
-    I = {Op,Fail,Info,Live,Ss,Dst},
-    reverse(Acc, [I|Is]);
-insert_alloc_1([{bs_put,_,_,_}=I|Is], Alloc, Acc) ->
-    insert_alloc_1(Is, Alloc, [I|Acc]).
-
-%% opt(Is0) -> Is
-%%  Simple peep-hole optimization to move a {move,Any,{x,0}} past
-%%  any kill up to the next call instruction. (To give the loader
-%%  an opportunity to combine the 'move' and the 'call' instructions.)
-%%
-opt(Is) ->
-    opt_1(Is, []).
-
-opt_1([{move,_,{x,0}}=I|Is0], Acc0) ->
-    case move_past_kill(Is0, I, Acc0) of
-	impossible -> opt_1(Is0, [I|Acc0]);
-	{Is,Acc} -> opt_1(Is, Acc)
-    end;
-opt_1([I|Is], Acc) ->
-    opt_1(Is, [I|Acc]);
-opt_1([], Acc) -> reverse(Acc).
-
-move_past_kill([{kill,Src}|_], {move,Src,_}, _) ->
-    impossible;
-move_past_kill([{kill,_}=I|Is], Move, Acc) ->
-    move_past_kill(Is, Move, [I|Acc]);
-move_past_kill([{trim,N,_}=I|Is], {move,Src,Dst}=Move, Acc) ->
-    case Src of
-	{y,Y} when Y < N-> impossible;
-	{y,Y} -> {Is,[{move,{y,Y-N},Dst},I|Acc]};
-	_ -> {Is,[Move,I|Acc]}
-    end;
-move_past_kill(Is, Move, Acc) ->
-    {Is,[Move|Acc]}.