averello/swift-mirror
1
0
Fork 0
mirror of https://github.com/apple/swift.git synced 2025-12-21 12:14:44 +01:00
Code Issues Packages Projects Releases Wiki Activity

Merge pull request #5300 from DougGregor/constraint-solver-cleanups

Browse Source
This commit is contained in:
swift-ci
2016-10-14 16:59:09 -07:00
committed by GitHub
parent 8212646c10 2e800f4acc
commit a4104d87d5
4 changed files with 38 additions and 65 deletions
Download Patch File Download Diff File Expand all files Collapse all files

86
lib/Sema/CSSimplify.cpp
View File

@@ -1178,6 +1178,31 @@ ConstraintSystem::matchTypes(Type type1, Type type2, TypeMatchKind kind,
if (kind != TypeMatchKind::ConformsTo && desugar1->isEqual(desugar2))
return SolutionKind::Solved;
// Local function that should be used to produce the return value whenever
// this function was unable to resolve the constraint. It should be used
// within \c matchTypes() as
//
// return formUnsolvedResult();
//
// along any unsolved path. No other returns should produce
// SolutionKind::Unsolved or inspect TMF_GenerateConstraints.
auto formUnsolvedResult = [&] {
// If we're supposed to generate constraints (i.e., this is a
// newly-generated constraint), do so now.
if (flags & TMF_GenerateConstraints) {
// Add a new constraint between these types. We consider the current
// type-matching problem to the "solved" by this addition, because
// this new constraint will be solved at a later point.
// Obviously, this must not happen at the top level, or the
// algorithm would not terminate.
addConstraint(getConstraintKind(kind), type1, type2,
getConstraintLocator(locator));
return SolutionKind::Solved;
}
return SolutionKind::Unsolved;
};
// If either (or both) types are type variables, unify the type variables.
if (typeVar1 || typeVar2) {
switch (kind) {
@@ -1196,24 +1221,8 @@ ConstraintSystem::matchTypes(Type type1, Type type2, TypeMatchKind kind,
// If exactly one of the type variables can bind to an lvalue, we
// can't merge these two type variables.
if (rep1->getImpl().canBindToLValue()
!= rep2->getImpl().canBindToLValue()) {
if (flags & TMF_GenerateConstraints) {
if (kind == TypeMatchKind::BindToPointerType) {
increaseScore(ScoreKind::SK_ScalarPointerConversion);
}
// Add a new constraint between these types. We consider the current
// type-matching problem to the "solved" by this addition, because
// this new constraint will be solved at a later point.
// Obviously, this must not happen at the top level, or the
// algorithm would not terminate.
addConstraint(getConstraintKind(kind), rep1, rep2,
getConstraintLocator(locator));
return SolutionKind::Solved;
}
return SolutionKind::Unsolved;
}
!= rep2->getImpl().canBindToLValue())
return formUnsolvedResult();
// Merge the equivalence classes corresponding to these two variables.
mergeEquivalenceClasses(rep1, rep2);
@@ -1246,8 +1255,7 @@ ConstraintSystem::matchTypes(Type type1, Type type2, TypeMatchKind kind,
// A constraint that binds any pointer to a void pointer is
// ineffective, since any pointer can be converted to a void pointer.
if (kind == TypeMatchKind::BindToPointerType && desugar2->isVoid() &&
(flags & TMF_GenerateConstraints)) {
if (kind == TypeMatchKind::BindToPointerType && desugar2->isVoid()) {
// Bind type1 to Void only as a last resort.
addConstraint(ConstraintKind::Defaultable, typeVar1, type2,
getConstraintLocator(locator));
@@ -1301,7 +1309,8 @@ ConstraintSystem::matchTypes(Type type1, Type type2, TypeMatchKind kind,
return SolutionKind::Solved;
}
}
return SolutionKind::Unsolved;
return formUnsolvedResult();
}
case TypeMatchKind::ArgumentTupleConversion:
@@ -1323,22 +1332,13 @@ ConstraintSystem::matchTypes(Type type1, Type type2, TypeMatchKind kind,
case TypeMatchKind::ArgumentConversion:
case TypeMatchKind::OperatorArgumentTupleConversion:
case TypeMatchKind::OperatorArgumentConversion:
if (flags & TMF_GenerateConstraints) {
// Add a new constraint between these types. We consider the current
// type-matching problem to the "solved" by this addition, because
// this new constraint will be solved at a later point.
// Obviously, this must not happen at the top level, or the algorithm
// would not terminate.
addConstraint(getConstraintKind(kind), type1, type2,
getConstraintLocator(locator));
return SolutionKind::Solved;
}
// We couldn't solve this constraint. If only one of the types is a type
// variable, perhaps we can do something with it below.
if (typeVar1 && typeVar2)
return typeVar1 == typeVar2 ? SolutionKind::Solved
: SolutionKind::Unsolved;
if (typeVar1 && typeVar2) {
if (typeVar1 == typeVar2) return SolutionKind::Solved;
return formUnsolvedResult();
}
break;
}
@@ -1355,18 +1355,7 @@ ConstraintSystem::matchTypes(Type type1, Type type2, TypeMatchKind kind,
return ::matchCallArguments(*this, kind, type1, type2, locator);
}
if (flags & TMF_GenerateConstraints) {
// Add a new constraint between these types. We consider the current
// type-matching problem to the "solved" by this addition, because
// this new constraint will be solved at a later point.
// Obviously, this must not happen at the top level, or the algorithm
// would not terminate.
addConstraint(getConstraintKind(kind), type1, type2,
getConstraintLocator(locator));
return SolutionKind::Solved;
}
return SolutionKind::Unsolved;
return formUnsolvedResult();
}
// Decompose parallel structure.
@@ -2067,8 +2056,7 @@ commit_to_conversions:
if (conversionsOrFixes.empty()) {
// If one of the types is a type variable, we leave this unsolved.
if (typeVar1 || typeVar2)
return SolutionKind::Unsolved;
if (typeVar1 || typeVar2) return formUnsolvedResult();
return SolutionKind::Error;
}