diff options
Diffstat (limited to 'lib/compiler/src/v3_codegen.erl')
-rw-r--r-- | lib/compiler/src/v3_codegen.erl | 73 |
1 files changed, 49 insertions, 24 deletions
diff --git a/lib/compiler/src/v3_codegen.erl b/lib/compiler/src/v3_codegen.erl index 2a89305f4d..f5f3c73793 100644 --- a/lib/compiler/src/v3_codegen.erl +++ b/lib/compiler/src/v3_codegen.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1999-2012. All Rights Reserved. +%% Copyright Ericsson AB 1999-2016. All Rights Reserved. %% %% Licensed under the Apache License, Version 2.0 (the "License"); %% you may not use this file except in compliance with the License. @@ -827,21 +827,24 @@ select_extract_bin([{var,Hd},{var,Tl}], Size0, Unit, Type, Flags, Vf, {bs_save2,CtxReg,{Ctx,Tl}}],Int1} end, {Es,clear_dead(Aft, I, Vdb),St}; -select_extract_bin([{var,Hd}], Size0, Unit, binary, Flags, Vf, +select_extract_bin([{var,Hd}], Size, Unit, binary, Flags, Vf, I, Vdb, Bef, Ctx, Body, St) -> - SizeReg = get_bin_size_reg(Size0, Bef), + %% Match the last segment of a binary. We KNOW that the size + %% must be 'all'. + Size = {atom,all}, %Assertion. {Es,Aft} = case vdb_find(Hd, Vdb) of {_,_,Lhd} when Lhd =< I -> + %% The result will not be used. Furthermore, since we + %% we are at the end of the binary, the position will + %% not be used again; thus, it is safe to do a cheaper + %% test of the unit. CtxReg = fetch_var(Ctx, Bef), - {case SizeReg =:= {atom,all} andalso is_context_unused(Body) of - true when Unit =:= 1 -> + {case Unit of + 1 -> []; - true -> - [{test,bs_test_unit,{f,Vf},[CtxReg,Unit]}]; - false -> - [{test,bs_skip_bits2,{f,Vf}, - [CtxReg,SizeReg,Unit,{field_flags,Flags}]}] + _ -> + [{test,bs_test_unit,{f,Vf},[CtxReg,Unit]}] end,Bef}; {_,_,_} -> case is_context_unused(Body) of @@ -853,7 +856,7 @@ select_extract_bin([{var,Hd}], Size0, Unit, binary, Flags, Vf, Name = bs_get_binary2, Live = max_reg(Bef#sr.reg), {[{test,Name,{f,Vf},Live, - [CtxReg,SizeReg,Unit,{field_flags,Flags}],Rhd}], + [CtxReg,Size,Unit,{field_flags,Flags}],Rhd}], Int1}; true -> %% Since the matching context will not be used again, @@ -868,7 +871,7 @@ select_extract_bin([{var,Hd}], Size0, Unit, binary, Flags, Vf, Name = bs_get_binary2, Live = max_reg(Int1#sr.reg), {[{test,Name,{f,Vf},Live, - [CtxReg,SizeReg,Unit,{field_flags,Flags}],CtxReg}], + [CtxReg,Size,Unit,{field_flags,Flags}],CtxReg}], Int1} end end, @@ -1086,6 +1089,23 @@ protected_cg(Ts, Rs, _Fail, I, Vdb, Bef, St0) -> %% test_cg(TestName, Args, Fail, I, Vdb, Bef, St) -> {[Ainstr],Aft,St}. %% Generate test instruction. Use explicit fail label here. +test_cg(is_map, [A], Fail, I, Vdb, Bef, St) -> + %% We must avoid creating code like this: + %% + %% move x(0) y(0) + %% is_map Fail [x(0)] + %% make_fun => x(0) %% Overwrite x(0) + %% put_map_assoc y(0) ... + %% + %% The code is safe, but beam_validator does not understand that. + %% Extending beam_validator to handle such (rare) code as the + %% above would make it slower for all programs. Instead, change + %% the code generator to always prefer the Y register for is_map() + %% and put_map_assoc() instructions, ensuring that they use the + %% same register. + Arg = cg_reg_arg_prefer_y(A, Bef), + Aft = clear_dead(Bef, I, Vdb), + {[{test,is_map,{f,Fail},[Arg]}],Aft,St}; test_cg(Test, As, Fail, I, Vdb, Bef, St) -> Args = cg_reg_args(As, Bef), Aft = clear_dead(Bef, I, Vdb), @@ -1152,19 +1172,15 @@ call_cg(Func, As, Rs, Le, Vdb, Bef, St0) -> %% Inside a guard. The only allowed function call is to %% erlang:error/1,2. We will generate the following code: %% - %% jump FailureLabel %% move {atom,ok} DestReg - %% - %% The 'move' instruction will never be executed, but we - %% generate it anyway in case the beam_validator is run - %% on unoptimized code. + %% jump FailureLabel {remote,{atom,erlang},{atom,error}} = Func, %Assertion. [{var,DestVar}] = Rs, Int0 = clear_dead(Bef, Le#l.i, Vdb), Reg = put_reg(DestVar, Int0#sr.reg), Int = Int0#sr{reg=Reg}, Dst = fetch_reg(DestVar, Reg), - {[{jump,{f,Fail}},{move,{atom,ok},Dst}], + {[{move,{atom,ok},Dst},{jump,{f,Fail}}], clear_dead(Int, Le#l.i, Vdb),St0}; #cg{} -> %% Ordinary function call in a function body. @@ -1542,7 +1558,7 @@ set_cg([{var,R}], {map,Op,Map,[{map_pair,{var,_}=K,V}]}, Le, Vdb, Bef, Fail = {f,Bfail}, {Sis,Int0} = maybe_adjust_stack(Bef, Le#l.i, Le#l.i+1, Vdb, St), - SrcReg = cg_reg_arg(Map,Int0), + SrcReg = cg_reg_arg_prefer_y(Map, Int0), Line = line(Le#l.a), List = [cg_reg_arg(K,Int0),cg_reg_arg(V,Int0)], @@ -1569,7 +1585,7 @@ set_cg([{var,R}], {map,Op,Map,Es}, Le, Vdb, Bef, Fail = {f,Bfail}, {Sis,Int0} = maybe_adjust_stack(Bef, Le#l.i, Le#l.i+1, Vdb, St), - SrcReg = cg_reg_arg(Map,Int0), + SrcReg = cg_reg_arg_prefer_y(Map, Int0), Line = line(Le#l.a), %% fetch registers for values to be put into the map @@ -1842,6 +1858,9 @@ cg_reg_args(As, Bef) -> [cg_reg_arg(A, Bef) || A <- As]. cg_reg_arg({var,V}, Bef) -> fetch_var(V, Bef); cg_reg_arg(Literal, _) -> Literal. +cg_reg_arg_prefer_y({var,V}, Bef) -> fetch_var_prefer_y(V, Bef); +cg_reg_arg_prefer_y(Literal, _) -> Literal. + %% cg_setup_call([Arg], Bef, Cur, Vdb) -> {[Instr],Aft}. %% Do the complete setup for a call/enter. @@ -2083,6 +2102,12 @@ fetch_var(V, Sr) -> error -> fetch_stack(V, Sr#sr.stk) end. +fetch_var_prefer_y(V, #sr{reg=Reg,stk=Stk}) -> + case find_stack(V, Stk) of + {ok,R} -> R; + error -> fetch_reg(V, Reg) + end. + load_vars(Vs, Regs) -> foldl(fun ({var,V}, Rs) -> put_reg(V, Rs) end, Regs, Vs). @@ -2156,11 +2181,11 @@ fetch_stack(Var, Stk) -> fetch_stack(Var, Stk, 0). fetch_stack(V, [{V}|_], I) -> {yy,I}; fetch_stack(V, [_|Stk], I) -> fetch_stack(V, Stk, I+1). -% find_stack(Var, Stk) -> find_stack(Var, Stk, 0). +find_stack(Var, Stk) -> find_stack(Var, Stk, 0). -% find_stack(V, [{V}|Stk], I) -> {ok,{yy,I}}; -% find_stack(V, [O|Stk], I) -> find_stack(V, Stk, I+1); -% find_stack(V, [], I) -> error. +find_stack(V, [{V}|_], I) -> {ok,{yy,I}}; +find_stack(V, [_|Stk], I) -> find_stack(V, Stk, I+1); +find_stack(_, [], _) -> error. on_stack(V, Stk) -> keymember(V, 1, Stk). |