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Type inference: Performance tweaks #22523

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78a4f9c
Shared: Add `InverseAppend` modules for effecient prefix matching
hvitved Sep 18, 2026
3720a8c
Type inference: Performance tweaks
hvitved Sep 18, 2026
80db2b2
Type inference: Revert inverse append changes
hvitved Sep 18, 2026
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65 changes: 52 additions & 13 deletions shared/typeinference/codeql/typeinference/internal/TypeInference.qll
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Original file line number Diff line number Diff line change
Expand Up @@ -1261,30 +1261,58 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
module MatchingWithEnvironment<MatchingWithEnvironmentInputSig Input> {
private import Input

private Type getTypeArgumentNonPseudo(Access a, int pos, TypePath path) {
result = a.getTypeArgument(pos, path) and
not result instanceof PseudoType
}

/**
* Gets the type of the type argument at `path` in `a` that corresponds to
* the type parameter `tp` in `target`, if any.
*
* Note that this predicate crucially does not depend on type inference,
* and hence can appear in negated position, e.g., as in
* `directTypeMatch`.
* and hence can appear in negated position, e.g., as in `directTypeMatch`.
*/
bindingset[a, target]
pragma[inline_late]
Type getTypeArgument(Access a, Declaration target, TypeParameter tp, TypePath path) {
exists(int pos |
result = a.getTypeArgument(pos, path) and
tp = target.getTypeParameter(pos) and
not result instanceof PseudoType
result = getTypeArgumentNonPseudo(a, pos, path) and
tp = target.getTypeParameter(pos)
)
}

bindingset[a, target]
pragma[inline_late]
private predicate hasNotTypeArgument0(Access a, Declaration target, TypeParameter tp) {
exists(int pos |
tp = target.getTypeParameter(pragma[only_bind_into](pos)) and
not exists(getTypeArgumentNonPseudo(a, pos, _))
)
}

bindingset[target, tp]
pragma[inline_late]
private predicate hasNotTypeArgument1(Declaration target, TypeParameter tp) {
not tp = target.getTypeParameter(_)
}

/**
* A join-order optimized version of `not exists(getTypeArgument(a, target, tp, _)`.
*/
pragma[inline]
private predicate hasNotTypeArgument(Access a, Declaration target, TypeParameter tp) {
hasNotTypeArgument0(a, target, tp)
or
hasNotTypeArgument1(target, tp)
}

pragma[nomagic]
private predicate directTypeMatch0(
Access a, DeclarationPosition dpos, AccessEnvironment e, Declaration target,
TypePath pathToTypeParam, TypeParameter tp
) {
not exists(getTypeArgument(a, target, tp, _)) and
hasNotTypeArgument(a, target, tp) and
tp = target.getDeclaredType(dpos, pathToTypeParam) and
target = a.getTarget(e)
}
Expand Down Expand Up @@ -1359,12 +1387,18 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
t = a.getInferredType(e, apos, TypePath::nil())
}

private predicate relevantAccessTarget(
Access a, AccessPosition apos, AccessEnvironment e, Declaration target
) {
exists(Type t |
accessTargetsWithArgRootType(a, e, target, apos, t) and
argRootTypeSatisfiesTargetTypeCand(t, target, apos, _, _)
)
}

private newtype TRelevantAccess =
MkRelevantAccess(Access a, AccessPosition apos, AccessEnvironment e) {
exists(Declaration target, Type t |
accessTargetsWithArgRootType(a, e, target, apos, t) and
argRootTypeSatisfiesTargetTypeCand(t, target, apos, _, _)
)
relevantAccessTarget(a, apos, e, _)
}

private class RelevantAccess extends MkRelevantAccess {
Expand All @@ -1374,7 +1408,12 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {

RelevantAccess() { this = MkRelevantAccess(a, apos, e) }

RelevantTarget getTarget() { result = MkRelevantTarget(a.getTarget(e), apos) }
RelevantTarget getTarget() {
exists(Declaration target |
relevantAccessTarget(a, apos, e, target) and
result = MkRelevantTarget(target, apos)
)
}

pragma[nomagic]
Type getTypeAt(TypePath path) { result = a.getInferredType(e, apos, path) }
Expand Down Expand Up @@ -1437,7 +1476,7 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
pragma[only_bind_into](apos), e),
MkRelevantTarget(target, pragma[only_bind_into](apos)), pathToTp.appendInverse(path),
t) and
not exists(getTypeArgument(a, target, tp, _))
hasNotTypeArgument(a, target, tp)
)
}
}
Expand Down Expand Up @@ -1595,7 +1634,7 @@ module Make1<LocationSig Location, InputSig1<Location> Input1> {
private predicate typeConstraintBaseTypeMatch(
Access a, AccessEnvironment e, Declaration target, TypePath path, Type t, TypeParameter tp
) {
not exists(getTypeArgument(a, target, tp, _)) and
hasNotTypeArgument(a, target, tp) and
exists(TypeMention constraint, TypeParameter constrainedTp, TypePath pathToTp |
typeParameterConstraintHasTypeParameter(target, constrainedTp, constraint, pathToTp, tp) and
AccessConstraint::satisfiesConstraint(a, e, target, constrainedTp, constraint,
Expand Down
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