File 6071-compiler-remove-NomatchGuard-from-strict-generators.patch of Package erlang
From 5e5d83c6de04e15ab1f45b5926a90c91bb4ae988 Mon Sep 17 00:00:00 2001
From: lucioleKi <isabell@erlang.org>
Date: Tue, 5 Nov 2024 13:26:05 +0100
Subject: [PATCH] compiler: remove NomatchGuard from strict generators
`NomatchGuard` was only needed for strict binary generators to test for non-empty
binaries. Now `TailPat` for strict binary generators is changed to an empty
binary, and `TailClause` is moved before `NomatchClause` for this case.
There is no need to have NomatchGuard anymore.
---
lib/compiler/src/v3_core.erl | 43 +++++++++++++++++++++---------------
1 file changed, 25 insertions(+), 18 deletions(-)
diff --git a/lib/compiler/src/v3_core.erl b/lib/compiler/src/v3_core.erl
index 448b321326..a7c04fe04e 100644
--- a/lib/compiler/src/v3_core.erl
+++ b/lib/compiler/src/v3_core.erl
@@ -121,7 +121,7 @@
-record(itry, {anno=#a{},args,vars,body,evars,handler}).
-record(ifilter, {anno=#a{},arg}).
-record(igen, {anno=#a{},acc_pat,acc_guard,
- nomatch_pat,nomatch_guard,nomatch_mode,
+ nomatch_pat,nomatch_mode,
tail,tail_pat,arg,
refill={nomatch,ignore}}).
-record(isimple, {anno=#a{},term :: cerl:cerl()}).
@@ -1605,7 +1605,6 @@ fun_tq(Cs0, L, St0, NameInfo) ->
lc_tq(Line, E, [#igen{anno=#a{anno=GA}=GAnno,
acc_pat=AccPat,acc_guard=AccGuard,
nomatch_pat=NomatchPat,
- nomatch_guard=NomatchGuard,
nomatch_mode=NomatchMode,
tail=Tail,tail_pat=TailPat,
refill={RefillPat,RefillAction},
@@ -1626,7 +1625,7 @@ lc_tq(Line, E, [#igen{anno=#a{anno=GA}=GAnno,
{[FcVar,Var],St2} = new_vars(2, St1),
Fc = bad_generator([FcVar], FcVar, Arg),
NomatchClause = make_clause([nomatch_clause,compiler_generated|LA],
- NomatchPat, [], NomatchGuard, [Nc]),
+ NomatchPat, [], [], [Nc]),
TailClause = make_clause(LA, TailPat, [], [], [Mc]),
{Lc,Lps,St3} = lc_tq(Line, E, Qs, Sc, St2),
AccClause = make_clause(LA, AccPat, [], AccGuard, Lps ++ [Lc]),
@@ -1640,7 +1639,15 @@ lc_tq(Line, E, [#igen{anno=#a{anno=GA}=GAnno,
AccPat, [], [], [Sc])
end,
RefillClause = make_clause(LA, RefillPat, [], [], [RefillAction,Sc]),
- Cs0 = [AccClause,AccClauseNoGuards,NomatchClause,TailClause,RefillClause],
+ Cs0 = [AccClause,AccClauseNoGuards|
+ case TailPat of
+ #ibinary{segments=[]} ->
+ %% Order clauses for strict binary generator.
+ [TailClause,NomatchClause,RefillClause];
+ _ ->
+ %% Order clauses for relaxed generator.
+ [NomatchClause,TailClause,RefillClause]
+ end],
Cs = [C || C <- Cs0, C =/= nomatch],
Fun = #ifun{anno=GAnno,id=[],vars=[Var],clauses=Cs,fc=Fc},
{#iletrec{anno=GAnno#a{anno=[list_comprehension|GA]},defs=[{{Name,1},Fun}],
@@ -1680,7 +1687,6 @@ bc_tq(Line, Exp, Qs0, St0) ->
bc_tq1(Line, E, [#igen{anno=#a{anno=GA}=GAnno,
acc_pat=AccPat,acc_guard=AccGuard,
nomatch_pat=NomatchPat,
- nomatch_guard=NomatchGuard,
nomatch_mode=NomatchMode,
tail=Tail,tail_pat=TailPat,
refill={RefillPat,RefillAction},
@@ -1704,7 +1710,7 @@ bc_tq1(Line, E, [#igen{anno=#a{anno=GA}=GAnno,
end,
Fc = bad_generator(FcVars, hd(FcVars), Arg),
NomatchClause = make_clause([compiler_generated,nomatch_clause|LA],
- NomatchPat, [IgnoreVar], NomatchGuard, [Nc]),
+ NomatchPat, [IgnoreVar], [], [Nc]),
TailClause = make_clause(LA, TailPat, [IgnoreVar], [], [AccVar]),
{Bc,Bps,St5} = bc_tq1(Line, E, Qs, AccVar, St4),
Body = Bps ++ [#iset{var=AccVar,arg=Bc},Sc],
@@ -1719,7 +1725,15 @@ bc_tq1(Line, E, [#igen{anno=#a{anno=GA}=GAnno,
AccPat, [IgnoreVar], [], [Sc])
end,
RefillClause = make_clause(LA, RefillPat, [AccVar], [], [RefillAction,Sc]),
- Cs0 = [AccClause,AccClauseNoGuards,NomatchClause,TailClause,RefillClause],
+ Cs0 = [AccClause,AccClauseNoGuards|
+ case TailPat of
+ #ibinary{segments=[]} ->
+ %% Order clauses for strict binary generator.
+ [TailClause,NomatchClause,RefillClause];
+ _ ->
+ %% Order clauses for relaxed generator.
+ [NomatchClause,TailClause,RefillClause]
+ end],
Cs = [C || C <- Cs0, C =/= nomatch],
Fun = #ifun{anno=GAnno,id=[],vars=Vars,clauses=Cs,fc=Fc},
@@ -1873,7 +1887,6 @@ get_qual_anno(Abstract) -> element(2, Abstract).
%% generator in the qualifier list input.
%% - nomatch_pat is the no-match pattern, e.g. <<X,_:X,Tail/bitstring>>
%% for <<X,1:X>> <= Expr.
-%% - nomatch_guard is the list of guards to add to the no-match clause.
%% - nomatch_mode is either skip (not matching elements of the relaxed
%% generator have to be silently skipped by the comprehension) or a
%% value X (to be used in the {badmatch, X} error a strict generator
@@ -1914,7 +1927,7 @@ generator(Line, {Generate,Lg,P0,E}, Gs, St0) when Generate =:= generate;
end,
{Ce,Pre,St4} = safe(E, St3),
Gen = #igen{anno=#a{anno=GA},acc_pat=AccPat,acc_guard=Cg,
- nomatch_pat=NomatchPat,nomatch_guard=[],nomatch_mode=NomatchMode,
+ nomatch_pat=NomatchPat,nomatch_mode=NomatchMode,
tail=Tail,tail_pat=#c_literal{anno=LA,val=[]},arg={Pre,Ce}},
{Gen,St4};
generator(Line, {Generate,Lg,P,E}, Gs, St0) when Generate =:= b_generate;
@@ -1965,7 +1978,7 @@ generator(Line, {Generate,Lg,P,E}, Gs, St0) when Generate =:= b_generate;
NomatchPat = Cp#ibinary{segments=SkipSegs},
{Ce,Pre,St5} = safe(E, St4),
Gen = #igen{anno=GAnno,acc_pat=AccPat,acc_guard=Cg,
- nomatch_pat=NomatchPat,nomatch_guard=[],nomatch_mode=skip,
+ nomatch_pat=NomatchPat,nomatch_mode=skip,
tail=Tail,tail_pat=#ibinary{anno=#a{anno=LA},segments=[TailSeg]},
arg={Pre,Ce}},
{Gen,St5};
@@ -1973,23 +1986,18 @@ generator(Line, {Generate,Lg,P,E}, Gs, St0) when Generate =:= b_generate;
{AccSegs,Tail,TailSeg,St2} = append_tail_segment(Segs, St1),
AccPat = Cp#ibinary{segments=AccSegs},
{Cg,St3} = lc_guard_tests(Gs, St2),
- Guard = #icall{anno=GAnno,
- module=#c_literal{anno=GA,val=erlang},
- name=#c_literal{anno=GA,val='=/='},
- args=[Tail,#c_literal{anno=GA,val= <<>>}]},
{Ce,Pre,St4} = safe(E, St3),
Gen = #igen{anno=GAnno,acc_pat=AccPat,acc_guard=Cg,
nomatch_pat=#ibinary{anno=#a{anno=LA},segments=[TailSeg]},
- nomatch_guard=[Guard],
nomatch_mode=Tail,
- tail=Tail,tail_pat=#ibinary{anno=#a{anno=LA},segments=[TailSeg]},
+ tail=Tail,tail_pat=#ibinary{anno=#a{anno=LA},segments=[]},
arg={Pre,Ce}},
{Gen,St4}
catch
throw:nomatch ->
{Ce,Pre,St1} = safe(E, St0),
Gen = #igen{anno=#a{anno=GA},acc_pat=nomatch,acc_guard=[],
- nomatch_pat=nomatch,nomatch_guard=[],nomatch_mode=skip,
+ nomatch_pat=nomatch,nomatch_mode=skip,
tail_pat=#c_var{name='_'},
arg={Pre,Ce}},
{Gen,St1}
@@ -2089,7 +2097,6 @@ generator(Line, {Generate,Lg,{map_field_exact,_,K0,V0},E}, Gs, St0) when
Gen = #igen{anno=#a{anno=GA},
acc_pat=AccPat,acc_guard=Cg,
nomatch_pat=NomatchPat,
- nomatch_guard=[],
nomatch_mode=NomatchMode,
tail=IterVar,tail_pat=#c_literal{anno=LA,val=none},
refill=Refill,
--
2.43.0
