8196074: Remove uses of loose type equality tests
Summary: Drop loose type equality check and replace usages to go throuhg the strict version
Reviewed-by: vromero
Contributed-by: bsrbnd@gmail.com
--- a/src/jdk.compiler/share/classes/com/sun/tools/javac/code/Type.java Wed Jan 24 14:07:11 2018 +0530
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/code/Type.java Wed Jan 24 17:24:32 2018 +0000
@@ -2107,9 +2107,8 @@
List<Type> prevBounds = bounds.get(ib);
if (bound == qtype) return;
for (Type b : prevBounds) {
- //check for redundancy - use strict version of isSameType on tvars
- //(as the standard version will lead to false positives w.r.t. clones ivars)
- if (types.isSameType(b, bound2, true)) return;
+ //check for redundancy - do not add same bound twice
+ if (types.isSameType(b, bound2)) return;
}
bounds.put(ib, prevBounds.prepend(bound2));
notifyBoundChange(ib, bound2, false);
--- a/src/jdk.compiler/share/classes/com/sun/tools/javac/code/Types.java Wed Jan 24 14:07:11 2018 +0530
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/code/Types.java Wed Jan 24 17:24:32 2018 +0000
@@ -1291,12 +1291,9 @@
* lists are of different length, return false.
*/
public boolean isSameTypes(List<Type> ts, List<Type> ss) {
- return isSameTypes(ts, ss, false);
- }
- public boolean isSameTypes(List<Type> ts, List<Type> ss, boolean strict) {
while (ts.tail != null && ss.tail != null
/*inlined: ts.nonEmpty() && ss.nonEmpty()*/ &&
- isSameType(ts.head, ss.head, strict)) {
+ isSameType(ts.head, ss.head)) {
ts = ts.tail;
ss = ss.tail;
}
@@ -1325,15 +1322,15 @@
* Is t the same type as s?
*/
public boolean isSameType(Type t, Type s) {
- return isSameType(t, s, false);
- }
- public boolean isSameType(Type t, Type s, boolean strict) {
- return strict ?
- isSameTypeStrict.visit(t, s) :
- isSameTypeLoose.visit(t, s);
+ return isSameTypeVisitor.visit(t, s);
}
// where
- abstract class SameTypeVisitor extends TypeRelation {
+
+ /**
+ * Type-equality relation - type variables are considered
+ * equals if they share the same object identity.
+ */
+ TypeRelation isSameTypeVisitor = new TypeRelation() {
public Boolean visitType(Type t, Type s) {
if (t.equalsIgnoreMetadata(s))
@@ -1350,7 +1347,7 @@
if (s.hasTag(TYPEVAR)) {
//type-substitution does not preserve type-var types
//check that type var symbols and bounds are indeed the same
- return sameTypeVars((TypeVar)t, (TypeVar)s);
+ return t == s;
}
else {
//special case for s == ? super X, where upper(s) = u
@@ -1365,8 +1362,6 @@
}
}
- abstract boolean sameTypeVars(TypeVar tv1, TypeVar tv2);
-
@Override
public Boolean visitWildcardType(WildcardType t, Type s) {
if (!s.hasTag(WILDCARD)) {
@@ -1374,7 +1369,7 @@
} else {
WildcardType t2 = (WildcardType)s;
return (t.kind == t2.kind || (t.isExtendsBound() && s.isExtendsBound())) &&
- isSameType(t.type, t2.type, true);
+ isSameType(t.type, t2.type);
}
}
@@ -1411,10 +1406,8 @@
}
return t.tsym == s.tsym
&& visit(t.getEnclosingType(), s.getEnclosingType())
- && containsTypes(t.getTypeArguments(), s.getTypeArguments());
- }
-
- abstract protected boolean containsTypes(List<Type> ts1, List<Type> ts2);
+ && containsTypeEquivalent(t.getTypeArguments(), s.getTypeArguments());
+ }
@Override
public Boolean visitArrayType(ArrayType t, Type s) {
@@ -1471,70 +1464,6 @@
public Boolean visitErrorType(ErrorType t, Type s) {
return true;
}
- }
-
- /**
- * Standard type-equality relation - type variables are considered
- * equals if they share the same type symbol.
- */
- TypeRelation isSameTypeLoose = new LooseSameTypeVisitor();
-
- private class LooseSameTypeVisitor extends SameTypeVisitor {
-
- /** cache of the type-variable pairs being (recursively) tested. */
- private Set<TypePair> cache = new HashSet<>();
-
- @Override
- boolean sameTypeVars(TypeVar tv1, TypeVar tv2) {
- return tv1.tsym == tv2.tsym && checkSameBounds(tv1, tv2);
- }
- @Override
- protected boolean containsTypes(List<Type> ts1, List<Type> ts2) {
- return containsTypeEquivalent(ts1, ts2);
- }
-
- /**
- * Since type-variable bounds can be recursive, we need to protect against
- * infinite loops - where the same bounds are checked over and over recursively.
- */
- private boolean checkSameBounds(TypeVar tv1, TypeVar tv2) {
- TypePair p = new TypePair(tv1, tv2, true);
- if (cache.add(p)) {
- try {
- return visit(tv1.getUpperBound(), tv2.getUpperBound());
- } finally {
- cache.remove(p);
- }
- } else {
- return false;
- }
- }
- };
-
- /**
- * Strict type-equality relation - type variables are considered
- * equals if they share the same object identity.
- */
- TypeRelation isSameTypeStrict = new SameTypeVisitor() {
- @Override
- boolean sameTypeVars(TypeVar tv1, TypeVar tv2) {
- return tv1 == tv2;
- }
- @Override
- protected boolean containsTypes(List<Type> ts1, List<Type> ts2) {
- return isSameTypes(ts1, ts2, true);
- }
-
- @Override
- public Boolean visitWildcardType(WildcardType t, Type s) {
- if (!s.hasTag(WILDCARD)) {
- return false;
- } else {
- WildcardType t2 = (WildcardType)s;
- return t.kind == t2.kind &&
- isSameType(t.type, t2.type, true);
- }
- }
};
// </editor-fold>
@@ -3848,17 +3777,11 @@
// where
class TypePair {
final Type t1;
- final Type t2;
- boolean strict;
+ final Type t2;;
TypePair(Type t1, Type t2) {
- this(t1, t2, false);
- }
-
- TypePair(Type t1, Type t2, boolean strict) {
this.t1 = t1;
this.t2 = t2;
- this.strict = strict;
}
@Override
public int hashCode() {
@@ -3869,8 +3792,8 @@
if (!(obj instanceof TypePair))
return false;
TypePair typePair = (TypePair)obj;
- return isSameType(t1, typePair.t1, strict)
- && isSameType(t2, typePair.t2, strict);
+ return isSameType(t1, typePair.t1)
+ && isSameType(t2, typePair.t2);
}
}
Set<TypePair> mergeCache = new HashSet<>();
@@ -4460,7 +4383,7 @@
Type tmpLower = Si.lower.hasTag(UNDETVAR) ? ((UndetVar)Si.lower).qtype : Si.lower;
if (!Si.bound.hasTag(ERROR) &&
!Si.lower.hasTag(ERROR) &&
- isSameType(tmpBound, tmpLower, false)) {
+ isSameType(tmpBound, tmpLower)) {
currentS.head = Si.bound;
}
}
--- a/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Infer.java Wed Jan 24 14:07:11 2018 +0530
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Infer.java Wed Jan 24 17:24:32 2018 +0000
@@ -565,7 +565,7 @@
List<Type> argtypes) {
final Type restype;
- if (spMethod == null || types.isSameType(spMethod.getReturnType(), syms.objectType, true)) {
+ if (spMethod == null || types.isSameType(spMethod.getReturnType(), syms.objectType)) {
// The return type of the polymorphic signature is polymorphic,
// and is computed from the enclosing tree E, as follows:
// if E is a cast, then use the target type of the cast expression
@@ -1227,8 +1227,8 @@
} else {
IncorporationBinaryOp that = (IncorporationBinaryOp)o;
return opKind == that.opKind &&
- types.isSameType(op1, that.op1, true) &&
- types.isSameType(op2, that.op2, true);
+ types.isSameType(op1, that.op1) &&
+ types.isSameType(op2, that.op2);
}
}
--- a/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/TransTypes.java Wed Jan 24 14:07:11 2018 +0530
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/TransTypes.java Wed Jan 24 17:24:32 2018 +0000
@@ -788,7 +788,7 @@
JCTypeCast typeCast = newExpression.hasTag(Tag.TYPECAST)
? (JCTypeCast) newExpression
: null;
- tree.expr = typeCast != null && types.isSameType(typeCast.type, originalTarget, true)
+ tree.expr = typeCast != null && types.isSameType(typeCast.type, originalTarget)
? typeCast.expr
: newExpression;
}