Skip to content

Commit 7893fdb

Browse files
stereotype441commit-bot@chromium.org
stereotype441
authored and
[email protected]
committed
Flow analysis: Rename State to FlowModel.
This makes the terminology consistent with dart-lang/language#473. No change other than renaming the class, sorting the file, and reformatting some comments. Change-Id: I81ab759decd0495f18d2afbe9a4c9d734f393b04 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/112037 Reviewed-by: Konstantin Shcheglov <[email protected]>
1 parent 4d6adbf commit 7893fdb

File tree

2 files changed

+95
-95
lines changed

2 files changed

+95
-95
lines changed

‎pkg/front_end/lib/src/fasta/flow_analysis/flow_analysis.dart‎

Lines changed: 55 additions & 55 deletions
Original file line numberDiff line numberDiff line change
@@ -60,7 +60,7 @@ class FlowAnalysis<Statement, Expression, Variable, Type> {
6060
final FunctionBodyAccess<Variable> functionBody;
6161

6262
/// The stack of states of variables that are not definitely assigned.
63-
final List<State<Variable, Type>> _stack = [];
63+
final List<FlowModel<Variable, Type>> _stack = [];
6464

6565
/// The mapping from labeled [Statement]s to the index in the [_stack]
6666
/// where the first related element is located. The number of elements
@@ -71,16 +71,16 @@ class FlowAnalysis<Statement, Expression, Variable, Type> {
7171
/// List of all variables passed to [add].
7272
final List<Variable> _addedVariables = [];
7373

74-
State<Variable, Type> _current;
74+
FlowModel<Variable, Type> _current;
7575

7676
/// The last boolean condition, for [_conditionTrue] and [_conditionFalse].
7777
Expression _condition;
7878

7979
/// The state when [_condition] evaluates to `true`.
80-
State<Variable, Type> _conditionTrue;
80+
FlowModel<Variable, Type> _conditionTrue;
8181

8282
/// The state when [_condition] evaluates to `false`.
83-
State<Variable, Type> _conditionFalse;
83+
FlowModel<Variable, Type> _conditionFalse;
8484

8585
/// If assertions are enabled, keeps track of all variables that have been
8686
/// passed into the API (other than through a call to [add]). The [finish]
@@ -100,7 +100,7 @@ class FlowAnalysis<Statement, Expression, Variable, Type> {
100100
TypeOperations<Variable, Type> typeOperations,
101101
FunctionBodyAccess<Variable> functionBody,
102102
) {
103-
var emptySet = State<Variable, Type>(false).notAssigned;
103+
var emptySet = FlowModel<Variable, Type>(false).notAssigned;
104104
return FlowAnalysis._(
105105
nodeOperations,
106106
typeOperations,
@@ -115,7 +115,7 @@ class FlowAnalysis<Statement, Expression, Variable, Type> {
115115
this.functionBody,
116116
this._emptySet,
117117
) {
118-
_current = State<Variable, Type>(true);
118+
_current = FlowModel<Variable, Type>(true);
119119
}
120120

121121
/// Return `true` if the current state is reachable.
@@ -357,8 +357,8 @@ class FlowAnalysis<Statement, Expression, Variable, Type> {
357357
}
358358

359359
void ifStatement_end(bool hasElse) {
360-
State<Variable, Type> afterThen;
361-
State<Variable, Type> afterElse;
360+
FlowModel<Variable, Type> afterThen;
361+
FlowModel<Variable, Type> afterElse;
362362
if (hasElse) {
363363
afterThen = _stack.removeLast();
364364
afterElse = _current;
@@ -604,9 +604,9 @@ class FlowAnalysis<Statement, Expression, Variable, Type> {
604604
}
605605
}
606606

607-
State<Variable, Type> _join(
608-
State<Variable, Type> first, State<Variable, Type> second) =>
609-
State.join(typeOperations, first, second);
607+
FlowModel<Variable, Type> _join(
608+
FlowModel<Variable, Type> first, FlowModel<Variable, Type> second) =>
609+
FlowModel.join(typeOperations, first, second);
610610

611611
/// If assertions are enabled, records that the given variable has been
612612
/// referenced. The [finish] method will verify that all referenced variables
@@ -629,27 +629,14 @@ class FlowAnalysis<Statement, Expression, Variable, Type> {
629629
}
630630
}
631631

632-
/// Accessor for function body information.
633-
abstract class FunctionBodyAccess<Variable> {
634-
bool isPotentiallyMutatedInClosure(Variable variable);
635-
636-
bool isPotentiallyMutatedInScope(Variable variable);
637-
}
638-
639-
/// Operations on nodes, abstracted from concrete node interfaces.
640-
abstract class NodeOperations<Expression> {
641-
/// If the [node] is a parenthesized expression, recursively unwrap it.
642-
Expression unwrapParenthesized(Expression node);
643-
}
644-
645-
/// An instance of the [State] class represents the information gathered by flow
646-
/// analysis at a single point in the control flow of the function or method
647-
/// being analyzed.
632+
/// An instance of the [FlowModel] class represents the information gathered by
633+
/// flow analysis at a single point in the control flow of the function or
634+
/// method being analyzed.
648635
///
649636
/// Instances of this class are immutable, so the methods below that "update"
650637
/// the state actually leave `this` unchanged and return a new state object.
651638
@visibleForTesting
652-
class State<Variable, Type> {
639+
class FlowModel<Variable, Type> {
653640
/// Indicates whether this point in the control flow is reachable.
654641
final bool reachable;
655642

@@ -675,14 +662,14 @@ class State<Variable, Type> {
675662
/// Creates a state object with the given [reachable] status. All variables
676663
/// are assumed to be unpromoted and already assigned, so joining another
677664
/// state with this one will have no effect on it.
678-
State(bool reachable)
665+
FlowModel(bool reachable)
679666
: this._(
680667
reachable,
681668
_VariableSet<Variable>._(const []),
682669
const {},
683670
);
684671

685-
State._(
672+
FlowModel._(
686673
this.reachable,
687674
this.notAssigned,
688675
this.promoted,
@@ -691,14 +678,14 @@ class State<Variable, Type> {
691678
/// Updates the state to track a newly declared local [variable]. The
692679
/// optional [assigned] boolean indicates whether the variable is assigned at
693680
/// the point of declaration.
694-
State<Variable, Type> add(Variable variable, {bool assigned: false}) {
681+
FlowModel<Variable, Type> add(Variable variable, {bool assigned: false}) {
695682
var newNotAssigned = assigned ? notAssigned : notAssigned.add(variable);
696683

697684
if (identical(newNotAssigned, notAssigned)) {
698685
return this;
699686
}
700687

701-
return State<Variable, Type>._(
688+
return FlowModel<Variable, Type>._(
702689
reachable,
703690
newNotAssigned,
704691
promoted,
@@ -710,7 +697,7 @@ class State<Variable, Type> {
710697
///
711698
/// TODO(paulberry): should this method mark the variable as definitely
712699
/// assigned? Does it matter?
713-
State<Variable, Type> markNonNullable(
700+
FlowModel<Variable, Type> markNonNullable(
714701
TypeOperations<Variable, Type> typeOperations, Variable variable) {
715702
var previousType = promoted[variable];
716703
previousType ??= typeOperations.variableType(variable);
@@ -719,7 +706,7 @@ class State<Variable, Type> {
719706
if (!typeOperations.isSameType(type, previousType)) {
720707
var newPromoted = <Variable, Type>{}..addAll(promoted);
721708
newPromoted[variable] = type;
722-
return State<Variable, Type>._(
709+
return FlowModel<Variable, Type>._(
723710
reachable,
724711
notAssigned,
725712
newPromoted,
@@ -738,7 +725,7 @@ class State<Variable, Type> {
738725
///
739726
/// TODO(paulberry): if the type is non-nullable, should this method mark the
740727
/// variable as definitely assigned? Does it matter?
741-
State<Variable, Type> promote(
728+
FlowModel<Variable, Type> promote(
742729
TypeOperations<Variable, Type> typeOperations,
743730
Variable variable,
744731
Type type,
@@ -750,7 +737,7 @@ class State<Variable, Type> {
750737
!typeOperations.isSameType(type, previousType)) {
751738
var newPromoted = <Variable, Type>{}..addAll(promoted);
752739
newPromoted[variable] = type;
753-
return State<Variable, Type>._(
740+
return FlowModel<Variable, Type>._(
754741
reachable,
755742
notAssigned,
756743
newPromoted,
@@ -779,12 +766,12 @@ class State<Variable, Type> {
779766
/// and only remove promotions if it can be shown that they aren't restored
780767
/// later in the loop body. If we switch to a fixed point analysis, we should
781768
/// be able to remove this method.
782-
State<Variable, Type> removePromotedAll(Set<Variable> variables) {
769+
FlowModel<Variable, Type> removePromotedAll(Set<Variable> variables) {
783770
var newPromoted = _removePromotedAll(promoted, variables);
784771

785772
if (identical(newPromoted, promoted)) return this;
786773

787-
return State<Variable, Type>._(
774+
return FlowModel<Variable, Type>._(
788775
reachable,
789776
notAssigned,
790777
newPromoted,
@@ -811,10 +798,10 @@ class State<Variable, Type> {
811798
/// state from the `try` block). Variables that are assigned in the `finally`
812799
/// block are considered "unsafe" because the assignment might have cancelled
813800
/// the effect of any promotion that occurred inside the `try` block.
814-
State<Variable, Type> restrict(
801+
FlowModel<Variable, Type> restrict(
815802
TypeOperations<Variable, Type> typeOperations,
816803
_VariableSet<Variable> emptySet,
817-
State<Variable, Type> other,
804+
FlowModel<Variable, Type> other,
818805
Set<Variable> unsafe,
819806
) {
820807
var newReachable = reachable && other.reachable;
@@ -883,10 +870,10 @@ class State<Variable, Type> {
883870

884871
/// Updates the state to indicate whether the control flow path is
885872
/// [reachable].
886-
State<Variable, Type> setReachable(bool reachable) {
873+
FlowModel<Variable, Type> setReachable(bool reachable) {
887874
if (this.reachable == reachable) return this;
888875

889-
return State<Variable, Type>._(
876+
return FlowModel<Variable, Type>._(
890877
reachable,
891878
notAssigned,
892879
promoted,
@@ -901,7 +888,7 @@ class State<Variable, Type> {
901888
/// previous type promotion is removed.
902889
///
903890
/// TODO(paulberry): allow for writes that preserve type promotions.
904-
State<Variable, Type> write(TypeOperations<Variable, Type> typeOperations,
891+
FlowModel<Variable, Type> write(TypeOperations<Variable, Type> typeOperations,
905892
_VariableSet<Variable> emptySet, Variable variable) {
906893
var newNotAssigned = typeOperations.isLocalVariable(variable)
907894
? notAssigned.remove(emptySet, variable)
@@ -914,7 +901,7 @@ class State<Variable, Type> {
914901
return this;
915902
}
916903

917-
return State<Variable, Type>._(
904+
return FlowModel<Variable, Type>._(
918905
reachable,
919906
newNotAssigned,
920907
newPromoted,
@@ -971,10 +958,10 @@ class State<Variable, Type> {
971958
/// are kept only if they are common to both input states; if a variable is
972959
/// promoted to one type in one state and a subtype in the other state, the
973960
/// less specific type promotion is kept.
974-
static State<Variable, Type> join<Variable, Type>(
961+
static FlowModel<Variable, Type> join<Variable, Type>(
975962
TypeOperations<Variable, Type> typeOperations,
976-
State<Variable, Type> first,
977-
State<Variable, Type> second,
963+
FlowModel<Variable, Type> first,
964+
FlowModel<Variable, Type> second,
978965
) {
979966
if (first == null) return second;
980967
if (second == null) return first;
@@ -985,9 +972,9 @@ class State<Variable, Type> {
985972
var newReachable = first.reachable || second.reachable;
986973
var newNotAssigned = first.notAssigned.union(second.notAssigned);
987974
var newPromoted =
988-
State.joinPromoted(typeOperations, first.promoted, second.promoted);
975+
FlowModel.joinPromoted(typeOperations, first.promoted, second.promoted);
989976

990-
return State._identicalOrNew(
977+
return FlowModel._identicalOrNew(
991978
first,
992979
second,
993980
newReachable,
@@ -1036,11 +1023,11 @@ class State<Variable, Type> {
10361023
return result;
10371024
}
10381025

1039-
/// Creates a new [State] object, unless it is equivalent to either [first] or
1040-
/// [second], in which case one of those objects is re-used.
1041-
static State<Variable, Type> _identicalOrNew<Variable, Type>(
1042-
State<Variable, Type> first,
1043-
State<Variable, Type> second,
1026+
/// Creates a new [FlowModel] object, unless it is equivalent to either
1027+
/// [first] or [second], in which case one of those objects is re-used.
1028+
static FlowModel<Variable, Type> _identicalOrNew<Variable, Type>(
1029+
FlowModel<Variable, Type> first,
1030+
FlowModel<Variable, Type> second,
10441031
bool newReachable,
10451032
_VariableSet<Variable> newNotAssigned,
10461033
Map<Variable, Type> newPromoted,
@@ -1056,7 +1043,7 @@ class State<Variable, Type> {
10561043
return second;
10571044
}
10581045

1059-
return State<Variable, Type>._(
1046+
return FlowModel<Variable, Type>._(
10601047
newReachable,
10611048
newNotAssigned,
10621049
newPromoted,
@@ -1079,6 +1066,19 @@ class State<Variable, Type> {
10791066
}
10801067
}
10811068

1069+
/// Accessor for function body information.
1070+
abstract class FunctionBodyAccess<Variable> {
1071+
bool isPotentiallyMutatedInClosure(Variable variable);
1072+
1073+
bool isPotentiallyMutatedInScope(Variable variable);
1074+
}
1075+
1076+
/// Operations on nodes, abstracted from concrete node interfaces.
1077+
abstract class NodeOperations<Expression> {
1078+
/// If the [node] is a parenthesized expression, recursively unwrap it.
1079+
Expression unwrapParenthesized(Expression node);
1080+
}
1081+
10821082
/// Operations on types, abstracted from concrete type interfaces.
10831083
abstract class TypeOperations<Variable, Type> {
10841084
/// Return `true` if the [variable] is a local variable, not a parameter.

0 commit comments

Comments
 (0)