diff options
Diffstat (limited to 'lib/compiler/src/beam_utils.erl')
| -rw-r--r-- | lib/compiler/src/beam_utils.erl | 58 |
1 files changed, 54 insertions, 4 deletions
diff --git a/lib/compiler/src/beam_utils.erl b/lib/compiler/src/beam_utils.erl index ffeff9ea81..cc6e54ca16 100644 --- a/lib/compiler/src/beam_utils.erl +++ b/lib/compiler/src/beam_utils.erl @@ -28,11 +28,31 @@ live_opt/1,delete_live_annos/1,combine_heap_needs/2, split_even/1]). +-export_type([code_index/0,module_code/0,instruction/0]). + -import(lists, [member/2,sort/1,reverse/1,splitwith/2]). +%% instruction() describes all instructions that are used during optimzation +%% (from beam_a to beam_z). +-type instruction() :: atom() | tuple(). + +-type code_index() :: gb_trees:tree(beam_asm:label(), [instruction()]). + +-type int_function() :: {'function',beam_asm:function_name(),arity(), + beam_asm:label(),[instruction()]}. + +-type module_code() :: + {module(),[_],[_],[int_function()],pos_integer()}. + +%% Internal types. +-type fail() :: beam_asm:fail() | 'fail'. +-type test() :: {'test',atom(),fail(),[beam_asm:src()]} | + {'test',atom(),fail(),integer(),list(),beam_asm:reg()}. +-type result_cache() :: gb_trees:tree(beam_asm:label(), 'killed' | 'used'). + -record(live, - {lbl, %Label to code index. - res}). %Result cache for each label. + {lbl :: code_index(), %Label to code index. + res :: result_cache()}). %Result cache for each label. %% is_killed_block(Register, [Instruction]) -> true|false @@ -44,6 +64,8 @@ %% i.e. it is OK to enter the instruction sequence with Register %% containing garbage. +-spec is_killed_block(beam_asm:reg(), [instruction()]) -> boolean(). + is_killed_block({x,X}, [{set,_,_,{alloc,Live,_}}|_]) -> X >= Live; is_killed_block(R, [{set,Ds,Ss,_Op}|Is]) -> @@ -65,6 +87,8 @@ is_killed_block(_, []) -> false. %% The state (constructed by index_instructions/1) is used to allow us %% to determine the kill state across branches. +-spec is_killed(beam_asm:reg(), [instruction()], code_index()) -> boolean(). + is_killed(R, Is, D) -> St = #live{lbl=D,res=gb_trees:empty()}, case check_liveness(R, Is, St) of @@ -75,6 +99,8 @@ is_killed(R, Is, D) -> %% is_killed_at(Reg, Lbl, State) -> true|false %% Determine whether Reg is killed at label Lbl. +-spec is_killed_at(beam_asm:reg(), beam_asm:label(), code_index()) -> boolean(). + is_killed_at(R, Lbl, D) when is_integer(Lbl) -> St0 = #live{lbl=D,res=gb_trees:empty()}, case check_liveness_at(R, Lbl, St0) of @@ -89,6 +115,8 @@ is_killed_at(R, Lbl, D) when is_integer(Lbl) -> %% The state is used to allow us to determine the usage state %% across branches. +-spec is_not_used(beam_asm:reg(), [instruction()], code_index()) -> boolean(). + is_not_used(R, Is, D) -> St = #live{lbl=D,res=gb_trees:empty()}, case check_liveness(R, Is, St) of @@ -100,18 +128,25 @@ is_not_used(R, Is, D) -> %% Index the instruction sequence so that we can quickly %% look up the instruction following a specific label. +-spec index_labels([instruction()]) -> code_index(). + index_labels(Is) -> index_labels_1(Is, []). %% empty_label_index() -> State %% Create an empty label index. +-spec empty_label_index() -> code_index(). + empty_label_index() -> gb_trees:empty(). %% index_label(Label, [Instruction], State) -> State %% Add an index for a label. +-spec index_label(beam_asm:label(), [instruction()], code_index()) -> + code_index(). + index_label(Lbl, Is0, Acc) -> Is = drop_labels(Is0), gb_trees:enter(Lbl, Is, Acc). @@ -120,12 +155,16 @@ index_label(Lbl, Is0, Acc) -> %% code_at(Label, State) -> [I]. %% Retrieve the code at the given label. +-spec code_at(beam_asm:label(), code_index()) -> [instruction()]. + code_at(L, Ll) -> gb_trees:get(L, Ll). %% bif_to_test(Bif, [Op], Fail) -> {test,Test,Fail,[Op]} %% Convert a BIF to a test. Fail if not possible. +-spec bif_to_test(atom(), list(), fail()) -> test(). + bif_to_test(is_atom, [_]=Ops, Fail) -> {test,is_atom,Fail,Ops}; bif_to_test(is_boolean, [_]=Ops, Fail) -> {test,is_boolean,Fail,Ops}; bif_to_test(is_binary, [_]=Ops, Fail) -> {test,is_binary,Fail,Ops}; @@ -158,6 +197,9 @@ bif_to_test(is_record, [_,_,_]=Ops, Fail) -> {test,is_record,Fail,Ops}. %% Return 'true' if the test instruction does not modify any %% registers and/or bit syntax matching state. %% + +-spec is_pure_test(test()) -> boolean(). + is_pure_test({test,is_eq,_,[_,_]}) -> true; is_pure_test({test,is_ne,_,[_,_]}) -> true; is_pure_test({test,is_eq_exact,_,[_,_]}) -> true; @@ -180,7 +222,9 @@ is_pure_test({test,Op,_,Ops}) -> %% whose destination is a register that will not be used. %% Also insert {'%live',Live,Regs} annotations at the beginning %% and end of each block. -%% + +-spec live_opt([instruction()]) -> [instruction()]. + live_opt(Is0) -> {[{label,Fail}|_]=Bef,[Fi|Is]} = splitwith(fun({func_info,_,_,_}) -> false; @@ -193,7 +237,9 @@ live_opt(Is0) -> %% delete_live_annos([Instruction]) -> [Instruction]. %% Delete all live annotations. -%% + +-spec delete_live_annos([instruction()]) -> [instruction()]. + delete_live_annos([{block,Bl0}|Is]) -> case delete_live_annos(Bl0) of [] -> delete_live_annos(Is); @@ -208,6 +254,8 @@ delete_live_annos([]) -> []. %% combine_heap_needs(HeapNeed1, HeapNeed2) -> HeapNeed %% Combine the heap need for two allocation instructions. +-spec combine_heap_needs(term(), term()) -> term(). + combine_heap_needs({alloc,Alloc1}, {alloc,Alloc2}) -> {alloc,combine_alloc_lists(Alloc1, Alloc2)}; combine_heap_needs({alloc,Alloc}, Words) when is_integer(Words) -> @@ -220,6 +268,8 @@ combine_heap_needs(H1, H2) when is_integer(H1), is_integer(H2) -> %% split_even/1 %% [1,2,3,4,5,6] -> {[1,3,5],[2,4,6]} +-spec split_even(list()) -> {list(),list()}. + split_even(Rs) -> split_even(Rs, [], []). |