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author | Adriaan Moors <adriaan.moors@typesafe.com> | 2016-03-14 19:17:52 -0700 |
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committer | Adriaan Moors <adriaan.moors@typesafe.com> | 2016-03-14 19:17:52 -0700 |
commit | d209a377bd73b71cb791f1b262acfe4b20b993c1 (patch) | |
tree | 55f100a96e152615502f2885066fd19e1c10017a /src/compiler | |
parent | 798462e739f23bb498b72675a57e4cc331404945 (diff) | |
parent | e7e1c77092ec0d64a6ecbb8b920d1b4cca74837f (diff) | |
download | scala-d209a377bd73b71cb791f1b262acfe4b20b993c1.tar.gz scala-d209a377bd73b71cb791f1b262acfe4b20b993c1.tar.bz2 scala-d209a377bd73b71cb791f1b262acfe4b20b993c1.zip |
Merge pull request #4974 from szeiger/wip/patmat-outertest
More conservative optimization for unnecessary outer ref checks
Diffstat (limited to 'src/compiler')
3 files changed, 31 insertions, 23 deletions
diff --git a/src/compiler/scala/tools/nsc/transform/ExplicitOuter.scala b/src/compiler/scala/tools/nsc/transform/ExplicitOuter.scala index 1a0b4cdec0..4abcc774da 100644 --- a/src/compiler/scala/tools/nsc/transform/ExplicitOuter.scala +++ b/src/compiler/scala/tools/nsc/transform/ExplicitOuter.scala @@ -486,7 +486,8 @@ abstract class ExplicitOuter extends InfoTransform // since we can't fix SI-4440 properly (we must drop the outer accessors of final classes when there's no immediate reference to them in sight) // at least don't crash... this duplicates maybeOmittable from constructors (acc.owner.isEffectivelyFinal && !acc.isOverridingSymbol)) { - currentRun.reporting.uncheckedWarning(tree.pos, "The outer reference in this type test cannot be checked at run time.") + if (!base.tpe.hasAnnotation(UncheckedClass)) + currentRun.reporting.uncheckedWarning(tree.pos, "The outer reference in this type test cannot be checked at run time.") transform(TRUE) // urgh... drop condition if there's no accessor (or if it may disappear after constructors) } else { // println("(base, acc)= "+(base, acc)) diff --git a/src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala b/src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala index ab3b25e76b..2b16995f0b 100644 --- a/src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala +++ b/src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala @@ -351,7 +351,7 @@ trait MatchApproximation extends TreeAndTypeAnalysis with ScalaLogic with MatchT object condStrategy extends TypeTestTreeMaker.TypeTestCondStrategy { type Result = Prop def and(a: Result, b: Result) = And(a, b) - def outerTest(testedBinder: Symbol, expectedTp: Type) = True // TODO OuterEqProp(testedBinder, expectedType) + def withOuterTest(testedBinder: Symbol, expectedTp: Type) = True // TODO OuterEqProp(testedBinder, expectedType) def typeTest(b: Symbol, pt: Type) = { // a type test implies the tested path is non-null (null.isInstanceOf[T] is false for all T) val p = binderToUniqueTree(b); And(uniqueNonNullProp(p), uniqueTypeProp(p, uniqueTp(pt))) } diff --git a/src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala b/src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala index c6e7f8fcda..8c59ced28f 100644 --- a/src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala +++ b/src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala @@ -316,7 +316,7 @@ trait MatchTreeMaking extends MatchCodeGen with Debugging { trait TypeTestCondStrategy { type Result - def outerTest(testedBinder: Symbol, expectedTp: Type): Result + def withOuterTest(orig: Result)(testedBinder: Symbol, expectedTp: Type): Result = orig // TODO: can probably always widen def typeTest(testedBinder: Symbol, expectedTp: Type): Result def nonNullTest(testedBinder: Symbol): Result @@ -336,18 +336,34 @@ trait MatchTreeMaking extends MatchCodeGen with Debugging { def equalsTest(pat: Tree, testedBinder: Symbol) = codegen._equals(pat, testedBinder) def eqTest(pat: Tree, testedBinder: Symbol) = REF(testedBinder) OBJ_EQ pat - def outerTest(testedBinder: Symbol, expectedTp: Type): Tree = { - val expectedOuter = expectedTp.prefix match { - case ThisType(clazz) => This(clazz) - case NoType => mkTRUE // fallback for SI-6183 - case pre => REF(pre.prefix, pre.termSymbol) + override def withOuterTest(orig: Tree)(testedBinder: Symbol, expectedTp: Type): Tree = { + val expectedPrefix = expectedTp.prefix + val testedPrefix = testedBinder.info.prefix + + // Check if a type is defined in a static location. Unlike `tp.isStatic` before `flatten`, + // this also includes methods and (possibly nested) objects inside of methods. + def definedInStaticLocation(tp: Type): Boolean = { + def isStatic(tp: Type): Boolean = + if (tp == NoType || tp.typeSymbol.isPackageClass || tp == NoPrefix) true + else if (tp.typeSymbol.isModuleClass) isStatic(tp.prefix) + else false + tp.typeSymbol.owner == tp.prefix.typeSymbol && isStatic(tp.prefix) } - // ExplicitOuter replaces `Select(q, outerSym) OBJ_EQ expectedPrefix` by `Select(q, outerAccessor(outerSym.owner)) OBJ_EQ expectedPrefix` - // if there's an outer accessor, otherwise the condition becomes `true` -- TODO: can we improve needsOuterTest so there's always an outerAccessor? - val outer = expectedTp.typeSymbol.newMethod(vpmName.outer, newFlags = SYNTHETIC | ARTIFACT) setInfo expectedTp.prefix - - (Select(codegen._asInstanceOf(testedBinder, expectedTp), outer)) OBJ_EQ expectedOuter + if ((expectedPrefix eq NoPrefix) + || definedInStaticLocation(expectedTp) + || testedPrefix =:= expectedPrefix) orig + else gen.mkAttributedQualifierIfPossible(expectedPrefix) match { + case None => orig + case Some(expectedOuterRef) => + // ExplicitOuter replaces `Select(q, outerSym) OBJ_EQ expectedPrefix` + // by `Select(q, outerAccessor(outerSym.owner)) OBJ_EQ expectedPrefix` + // if there's an outer accessor, otherwise the condition becomes `true` + // TODO: centralize logic whether there's an outer accessor and use here? + val synthOuterGetter = expectedTp.typeSymbol.newMethod(vpmName.outer, newFlags = SYNTHETIC | ARTIFACT) setInfo expectedPrefix + val outerTest = (Select(codegen._asInstanceOf(testedBinder, expectedTp), synthOuterGetter)) OBJ_EQ expectedOuterRef + and(orig, outerTest) + } } } @@ -356,7 +372,6 @@ trait MatchTreeMaking extends MatchCodeGen with Debugging { def typeTest(testedBinder: Symbol, expectedTp: Type): Result = true - def outerTest(testedBinder: Symbol, expectedTp: Type): Result = false def nonNullTest(testedBinder: Symbol): Result = false def equalsTest(pat: Tree, testedBinder: Symbol): Result = false def eqTest(pat: Tree, testedBinder: Symbol): Result = false @@ -368,7 +383,6 @@ trait MatchTreeMaking extends MatchCodeGen with Debugging { type Result = Boolean def typeTest(testedBinder: Symbol, expectedTp: Type): Result = testedBinder eq binder - def outerTest(testedBinder: Symbol, expectedTp: Type): Result = false def nonNullTest(testedBinder: Symbol): Result = testedBinder eq binder def equalsTest(pat: Tree, testedBinder: Symbol): Result = false // could in principle analyse pat and see if it's statically known to be non-null def eqTest(pat: Tree, testedBinder: Symbol): Result = false // could in principle analyse pat and see if it's statically known to be non-null @@ -405,12 +419,6 @@ trait MatchTreeMaking extends MatchCodeGen with Debugging { import TypeTestTreeMaker._ debug.patmat("TTTM"+((prevBinder, extractorArgTypeTest, testedBinder, expectedTp, nextBinderTp))) - lazy val outerTestNeeded = ( - (expectedTp.prefix ne NoPrefix) - && !expectedTp.prefix.typeSymbol.isPackageClass - && needsOuterTest(expectedTp, testedBinder.info, matchOwner) - ) - // the logic to generate the run-time test that follows from the fact that // a `prevBinder` is expected to have type `expectedTp` // the actual tree-generation logic is factored out, since the analyses generate Cond(ition)s rather than Trees @@ -429,12 +437,11 @@ trait MatchTreeMaking extends MatchCodeGen with Debugging { def isExpectedPrimitiveType = isAsExpected && isPrimitiveValueType(expectedTp) def isExpectedReferenceType = isAsExpected && (expectedTp <:< AnyRefTpe) def mkNullTest = nonNullTest(testedBinder) - def mkOuterTest = outerTest(testedBinder, expectedTp) def mkTypeTest = typeTest(testedBinder, expectedWide) def mkEqualsTest(lhs: Tree): cs.Result = equalsTest(lhs, testedBinder) def mkEqTest(lhs: Tree): cs.Result = eqTest(lhs, testedBinder) - def addOuterTest(res: cs.Result): cs.Result = if (outerTestNeeded) and(res, mkOuterTest) else res + def addOuterTest(res: cs.Result): cs.Result = withOuterTest(res)(testedBinder, expectedTp) // If we conform to expected primitive type: // it cannot be null and cannot have an outer pointer. No further checking. |