// FindReferencesInScope finds all identifier expressions that refer to the given name, under the given
// scope.
func (g *SRG) FindReferencesInScope(name string, node compilergraph.GraphNode) compilergraph.NodeIterator {
// Note: This filter ensures that the name is accessible in the scope of the given node by checking that
// the node referencing the name is contained by the given node.
containingFilter := func(q compilergraph.GraphQuery) compilergraph.Query {
startRune := node.GetValue(parser.NodePredicateStartRune).Int()
endRune := node.GetValue(parser.NodePredicateEndRune).Int()
return q.
HasWhere(parser.NodePredicateStartRune, compilergraph.WhereGT, startRune).
HasWhere(parser.NodePredicateEndRune, compilergraph.WhereLT, endRune)
}
return g.layer.StartQuery(name).
In(parser.NodeIdentifierExpressionName).
IsKind(parser.NodeTypeIdentifierExpression).
Has(parser.NodePredicateSource, node.Get(parser.NodePredicateSource)).
FilterBy(containingFilter).
BuildNodeIterator()
}
// OutOfScope returns any resources that will be out of scope when context changes to the given reference
// node. Used to determine which resources need to be popped off of the stack when jumps occurr. Note that
// the reference node *must be an SRG node*.
func (s *ResourceStack) OutOfScope(referenceNode compilergraph.GraphNode) []resource {
resources := make([]resource, 0)
// Find the start and end location for the reference node.
referenceStart := referenceNode.GetValue(parser.NodePredicateStartRune).Int()
referenceEnd := referenceNode.GetValue(parser.NodePredicateEndRune).Int()
var current = s.top
for index := 0; index < s.size; index++ {
currentResource := current.value
// Find the start and end location for the resource node.
resourceStart := currentResource.basis.GetValue(parser.NodePredicateStartRune).Int()
resourceEnd := currentResource.basis.GetValue(parser.NodePredicateEndRune).Int()
if !(referenceStart >= resourceStart && referenceEnd <= resourceEnd) {
resources = append(resources, currentResource)
}
current = current.next
}
return resources
}
// salForNode returns a SourceAndLocation for the given graph node.
func salForNode(node compilergraph.GraphNode) compilercommon.SourceAndLocation {
return compilercommon.NewSourceAndLocation(
compilercommon.InputSource(node.Get(parser.NodePredicateSource)),
node.GetValue(parser.NodePredicateStartRune).Int())
}
// findAddedNameInScope finds the {parameter, with, loop, var} node exposing the given name, if any.
func (g *SRG) findAddedNameInScope(name string, node compilergraph.GraphNode) (compilergraph.GraphNode, bool) {
nodeSource := node.Get(parser.NodePredicateSource)
nodeStartIndex := node.GetValue(parser.NodePredicateStartRune).Int()
// Note: This filter ensures that the name is accessible in the scope of the given node by checking that
// the node adding the name contains the given node.
containingFilter := func(q compilergraph.GraphQuery) compilergraph.Query {
startRune := node.GetValue(parser.NodePredicateStartRune).Int()
endRune := node.GetValue(parser.NodePredicateEndRune).Int()
return q.
In(parser.NodePredicateTypeMemberParameter,
parser.NodeLambdaExpressionInferredParameter,
parser.NodeLambdaExpressionParameter,
parser.NodePredicateTypeMemberGeneric,
parser.NodeStatementNamedValue,
parser.NodeAssignedDestination,
parser.NodeAssignedRejection,
parser.NodePredicateChild,
parser.NodeStatementBlockStatement).
InIfKind(parser.NodeStatementBlockStatement, parser.NodeTypeResolveStatement).
HasWhere(parser.NodePredicateStartRune, compilergraph.WhereLTE, startRune).
HasWhere(parser.NodePredicateEndRune, compilergraph.WhereGTE, endRune)
}
nit := g.layer.StartQuery(name).
In("named").
Has(parser.NodePredicateSource, nodeSource).
IsKind(parser.NodeTypeParameter, parser.NodeTypeNamedValue, parser.NodeTypeAssignedValue,
parser.NodeTypeVariableStatement, parser.NodeTypeLambdaParameter, parser.NodeTypeGeneric).
FilterBy(containingFilter).
BuildNodeIterator(parser.NodePredicateStartRune, parser.NodePredicateEndRune)
// Sort the nodes found by location and choose the closest node.
var results = make(scopeResultNodes, 0)
for nit.Next() {
node := nit.Node()
startIndex := nit.GetPredicate(parser.NodePredicateStartRune).Int()
// If the node is a variable statement or assigned value, we have do to additional checks
// (since they are not block scoped but rather statement scoped).
if node.Kind() == parser.NodeTypeVariableStatement || node.Kind() == parser.NodeTypeAssignedValue {
endIndex := nit.GetPredicate(parser.NodePredicateEndRune).Int()
if node.Kind() == parser.NodeTypeAssignedValue {
if parentNode, ok := node.TryGetIncomingNode(parser.NodeAssignedDestination); ok {
endIndex = parentNode.GetValue(parser.NodePredicateEndRune).Int()
} else if parentNode, ok := node.TryGetIncomingNode(parser.NodeAssignedRejection); ok {
endIndex = parentNode.GetValue(parser.NodePredicateEndRune).Int()
} else {
panic("Missing assigned parent")
}
}
// Check that the startIndex of the variable statement is <= the startIndex of the parent node
if startIndex > nodeStartIndex {
continue
}
// Ensure that the scope starts after the end index of the variable. Otherwise, the variable
// name could be used in its initializer expression (which is expressly disallowed).
if nodeStartIndex <= endIndex {
continue
}
}
results = append(results, scopeResultNode{node, startIndex})
}
if len(results) == 1 {
// If there is a single result, return it.
return results[0].node, true
} else if len(results) > 1 {
// Otherwise, sort the list by startIndex and choose the one closest to the scope node.
sort.Sort(results)
return results[0].node, true
}
return compilergraph.GraphNode{}, false
}
// GetUniqueId returns a unique hash ID for the SRG node that is stable across compilations.
func GetUniqueId(srgNode compilergraph.GraphNode) string {
hashBytes := []byte(srgNode.Get(parser.NodePredicateSource) + ":" + strconv.Itoa(srgNode.GetValue(parser.NodePredicateStartRune).Int()))
sha256bytes := sha256.Sum256(hashBytes)
return hex.EncodeToString(sha256bytes[:])[0:8]
}
