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-rw-r--r--lib/compiler/src/v3_codegen.erl94
1 files changed, 61 insertions, 33 deletions
diff --git a/lib/compiler/src/v3_codegen.erl b/lib/compiler/src/v3_codegen.erl
index 8189420c1c..62c6c54b9f 100644
--- a/lib/compiler/src/v3_codegen.erl
+++ b/lib/compiler/src/v3_codegen.erl
@@ -446,7 +446,7 @@ cg_fun(Les, Hvs, Vdb, AtomMod, NameArity, Anno, St0) ->
put_reg(V, Reg)
end, [], Hvs),
stk=[]}, 0, Vdb),
- {B,_Aft,St} = cg_list(Les, 0, Vdb, Bef,
+ {B,_Aft,St} = cg_list(Les, Vdb, Bef,
St3#cg{bfail=0,
ultimate_failure=UltimateMatchFail,
is_top_block=true}),
@@ -498,19 +498,19 @@ cg(#cg_need_heap{h=H}, _Vdb, Bef, St) ->
%% cg_list([Kexpr], FirstI, Vdb, StackReg, St) -> {[Ainstr],StackReg,St}.
-cg_list(Kes, I, Vdb, Bef, St0) ->
+cg_list(Kes, Vdb, Bef, St0) ->
{Keis,{Aft,St1}} =
flatmapfoldl(fun (Ke, {Inta,Sta}) ->
{Keis,Intb,Stb} = cg(Ke, Vdb, Inta, Sta),
{Keis,{Intb,Stb}}
- end, {Bef,St0}, need_heap(Kes, I)),
+ end, {Bef,St0}, need_heap(Kes)),
{Keis,Aft,St1}.
%% need_heap([Lkexpr], I, St) -> [Lkexpr].
%% Insert need_heap instructions in Kexpr list. Try to be smart and
%% collect them together as much as possible.
-need_heap(Kes0, _I) ->
+need_heap(Kes0) ->
{Kes,H} = need_heap_0(reverse(Kes0), 0, []),
%% Prepend need_heap if necessary.
@@ -741,26 +741,55 @@ block_cg(Es, Le, _Vdb, Bef, St) ->
block_cg(Es, Le, Bef, St).
block_cg(Es, Le, Bef, #cg{is_top_block=false}=St) ->
- cg_block(Es, Le#l.i, Le#l.vdb, Bef, St);
-block_cg(Es, Le, Bef, St0) ->
- {Is0,Aft,St} = cg_block(Es, Le#l.i, Le#l.vdb, Bef,
- St0#cg{is_top_block=false,need_frame=false}),
- Is = top_level_block(Is0, Aft, max_reg(Bef#sr.reg), St),
- {Is,Aft,St#cg{is_top_block=true}}.
-
-cg_block([], _I, _Vdb, Bef, St0) ->
+ cg_block(Es, Le#l.vdb, Bef, St);
+block_cg(Es, Le, Bef, #cg{is_top_block=true}=St0) ->
+ %% No stack frame has been established yet. Do we need one?
+ case need_stackframe(Es) of
+ true ->
+ %% We need a stack frame. Generate the code and add the
+ %% code for creating and deallocating the stack frame.
+ {Is0,Aft,St} = cg_block(Es, Le#l.vdb, Bef,
+ St0#cg{is_top_block=false,need_frame=false}),
+ Is = top_level_block(Is0, Aft, max_reg(Bef#sr.reg), St),
+ {Is,Aft,St#cg{is_top_block=true}};
+ false ->
+ %% This sequence of instructions ending in a #k_match{} (a
+ %% 'case' or 'if') in the Erlang code does not need a
+ %% stack frame yet. Delay the creation (if a stack frame
+ %% is needed at all, it will be created inside the
+ %% #k_match{}).
+ cg_list(Es, Le#l.vdb, Bef, St0)
+ end.
+
+%% need_stackframe([Kexpr]) -> true|false.
+%% Does this list of instructions need a stack frame?
+%%
+%% A sequence of instructions that don't clobber the X registers
+%% followed by a single #k_match{} doesn't need a stack frame.
+
+need_stackframe([H|T]) ->
+ case H of
+ #k_bif{op=#k_internal{}} -> true;
+ #k_put{arg=#k_binary{}} -> true;
+ #k_bif{} -> need_stackframe(T);
+ #k_put{} -> need_stackframe(T);
+ #k_guard_match{} -> need_stackframe(T);
+ #k_match{} when T =:= [] -> false;
+ _ -> true
+ end;
+need_stackframe([]) -> false.
+
+cg_block([], _Vdb, Bef, St0) ->
{[],Bef,St0};
-cg_block(Kes0, I, Vdb, Bef, St0) ->
+cg_block(Kes0, Vdb, Bef, St0) ->
{Kes2,Int1,St1} =
case basic_block(Kes0) of
{Kes1,LastI,Args,Rest} ->
- Ke = hd(Kes1),
- #l{i=Fb} = get_kanno(Ke),
- cg_basic_block(Kes1, Fb, LastI, Args, Vdb, Bef, St0);
+ cg_basic_block(Kes1, LastI, Args, Vdb, Bef, St0);
{Kes1,Rest} ->
- cg_list(Kes1, I, Vdb, Bef, St0)
+ cg_list(Kes1, Vdb, Bef, St0)
end,
- {Kes3,Int2,St2} = cg_block(Rest, I, Vdb, Int1, St1),
+ {Kes3,Int2,St2} = cg_block(Rest, Vdb, Int1, St1),
{Kes2 ++ Kes3,Int2,St2}.
basic_block(Kes) -> basic_block(Kes, []).
@@ -838,12 +867,12 @@ func_vars(_) -> [].
%% save_carefully/4 during code generation to only save the variables
%% that can be saved without growing the stack frame.
-cg_basic_block(Kes, Fb, Lf, As, Vdb, Bef, St0) ->
+cg_basic_block(Kes, Lf, As, Vdb, Bef, St0) ->
Int0 = reserve_arg_regs(As, Bef),
Int = extend_stack(Int0, Lf, Lf+1, Vdb),
{Keis,{Aft,St1}} =
flatmapfoldl(fun(Ke, St) -> cg_basic_block(Ke, St, Lf, Vdb) end,
- {Int,St0}, need_heap(Kes, Fb)),
+ {Int,St0}, need_heap(Kes)),
{Keis,Aft,St1}.
cg_basic_block(#cg_need_heap{}=Ke, {Bef,St0}, _Lf, Vdb) ->
@@ -1478,8 +1507,8 @@ guard_clause_cg(#k_guard_clause{anno=#l{vdb=Vdb},guard=G,body=B}, Fail, Bef, St0
%% the correct exit point. Primops and tests all go to the next
%% instruction on success or jump to a failure label.
-guard_cg(#k_protected{arg=Ts,ret=Rs,anno=#l{i=I,vdb=Pdb}}, Fail, _Vdb, Bef, St) ->
- protected_cg(Ts, Rs, Fail, I, Pdb, Bef, St);
+guard_cg(#k_protected{arg=Ts,ret=Rs,anno=#l{vdb=Pdb}}, Fail, _Vdb, Bef, St) ->
+ protected_cg(Ts, Rs, Fail, Pdb, Bef, St);
guard_cg(#k_test{anno=#l{i=I},op=Test0,args=As,inverted=Inverted},
Fail, Vdb, Bef, St0) ->
#k_remote{mod=#k_atom{val=erlang},name=#k_atom{val=Test}} = Test0,
@@ -1500,13 +1529,13 @@ guard_cg(G, _Fail, Vdb, Bef, St) ->
%% guard_cg_list([Kexpr], Fail, I, Vdb, StackReg, St) ->
%% {[Ainstr],StackReg,St}.
-guard_cg_list(Kes, Fail, I, Vdb, Bef, St0) ->
+guard_cg_list(Kes, Fail, Vdb, Bef, St0) ->
{Keis,{Aft,St1}} =
flatmapfoldl(fun (Ke, {Inta,Sta}) ->
{Keis,Intb,Stb} =
guard_cg(Ke, Fail, Vdb, Inta, Sta),
{Keis,{Intb,Stb}}
- end, {Bef,St0}, need_heap(Kes, I)),
+ end, {Bef,St0}, need_heap(Kes)),
{Keis,Aft,St1}.
%% protected_cg([Kexpr], [Ret], Fail, I, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
@@ -1516,15 +1545,14 @@ guard_cg_list(Kes, Fail, I, Vdb, Bef, St0) ->
%% return values then these must be set to 'false' on failure,
%% control always passes to the next instruction.
-protected_cg(Ts, [], Fail, I, Vdb, Bef, St0) ->
+protected_cg(Ts, [], Fail, Vdb, Bef, St0) ->
%% Protect these calls, revert when done.
- {Tis,Aft,St1} = guard_cg_list(Ts, Fail, I, Vdb, Bef,
- St0#cg{bfail=Fail}),
+ {Tis,Aft,St1} = guard_cg_list(Ts, Fail, Vdb, Bef, St0#cg{bfail=Fail}),
{Tis,Aft,St1#cg{bfail=St0#cg.bfail}};
-protected_cg(Ts, Rs, _Fail, I, Vdb, Bef, St0) ->
+protected_cg(Ts, Rs, _Fail, Vdb, Bef, St0) ->
{Pfail,St1} = new_label(St0),
{Psucc,St2} = new_label(St1),
- {Tis,Aft,St3} = guard_cg_list(Ts, Pfail, I, Vdb, Bef,
+ {Tis,Aft,St3} = guard_cg_list(Ts, Pfail, Vdb, Bef,
St2#cg{bfail=Pfail}),
%%ok = io:fwrite("cg ~w: ~p~n", [?LINE,{Rs,I,Vdb,Aft}]),
%% Set return values to false.
@@ -1896,17 +1924,17 @@ cg_recv_wait(#k_atom{val=infinity}, #cg_block{anno=Le,es=Tes}, I, Bef, St0) ->
%% But to keep the stack and register information up to date,
%% we will generate the code for the 'after' body, and then discard it.
Int1 = clear_dead(Bef, I, Le#l.vdb),
- {_,Int2,St1} = cg_block(Tes, Le#l.i, Le#l.vdb,
+ {_,Int2,St1} = cg_block(Tes, Le#l.vdb,
Int1#sr{reg=clear_regs(Int1#sr.reg)}, St0),
{[{wait,{f,St1#cg.recv}}],Int2,St1};
cg_recv_wait(#k_int{val=0}, #cg_block{anno=Le,es=Tes}, _I, Bef, St0) ->
- {Tis,Int,St1} = cg_block(Tes, Le#l.i, Le#l.vdb, Bef, St0),
+ {Tis,Int,St1} = cg_block(Tes, Le#l.vdb, Bef, St0),
{[timeout|Tis],Int,St1};
cg_recv_wait(Te, #cg_block{anno=Le,es=Tes}, I, Bef, St0) ->
Reg = cg_reg_arg(Te, Bef),
%% Must have empty registers here! Bug if anything in registers.
Int0 = clear_dead(Bef, I, Le#l.vdb),
- {Tis,Int,St1} = cg_block(Tes, Le#l.i, Le#l.vdb,
+ {Tis,Int,St1} = cg_block(Tes, Le#l.vdb,
Int0#sr{reg=clear_regs(Int0#sr.reg)}, St0),
{[{wait_timeout,{f,St1#cg.recv},Reg},timeout] ++ Tis,Int,St1}.
@@ -1967,7 +1995,7 @@ catch_cg(#cg_block{es=C}, #k_var{name=R}, Le, Vdb, Bef, St0) ->
CatchTag = Le#l.i,
Int1 = Bef#sr{stk=put_catch(CatchTag, Bef#sr.stk)},
CatchReg = fetch_stack({catch_tag,CatchTag}, Int1#sr.stk),
- {Cis,Int2,St2} = cg_block(C, Le#l.i, Le#l.vdb, Int1,
+ {Cis,Int2,St2} = cg_block(C, Le#l.vdb, Int1,
St1#cg{break=B,in_catch=true}),
[] = Int2#sr.reg, %Assertion.
Aft = Int2#sr{reg=[{0,R}],stk=drop_catch(CatchTag, Int2#sr.stk)},
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-07 08:40:51 +0000