// Builds the graph + StratifiedSets for a function.
CFLAAResult::FunctionInfo CFLAAResult::buildSetsFrom(Function *Fn) {
CFLGraphBuilder GraphBuilder(*this, TLI, *Fn);
StratifiedSetsBuilder<Value *> SetBuilder;
auto &Graph = GraphBuilder.getCFLGraph();
SmallVector<Value *, 16> Worklist;
for (auto Node : Graph.nodes())
Worklist.push_back(Node);
while (!Worklist.empty()) {
auto *CurValue = Worklist.pop_back_val();
SetBuilder.add(CurValue);
if (canSkipAddingToSets(CurValue))
continue;
auto Attr = Graph.attrFor(CurValue);
SetBuilder.noteAttributes(CurValue, Attr);
for (const auto &Edge : Graph.edgesFor(CurValue)) {
auto Label = Edge.Type;
auto *OtherValue = Edge.Other;
if (canSkipAddingToSets(OtherValue))
continue;
bool Added;
switch (directionOfEdgeType(Label)) {
case Level::Above:
Added = SetBuilder.addAbove(CurValue, OtherValue);
break;
case Level::Below:
Added = SetBuilder.addBelow(CurValue, OtherValue);
break;
case Level::Same:
Added = SetBuilder.addWith(CurValue, OtherValue);
break;
}
if (Added)
Worklist.push_back(OtherValue);
}
}
// Special handling for globals and arguments
for (auto *External : GraphBuilder.getExternalValues()) {
SetBuilder.add(External);
auto Attr = valueToAttr(External);
if (Attr.hasValue()) {
SetBuilder.noteAttributes(External, *Attr);
if (*Attr == AttrGlobal)
SetBuilder.addAttributesBelow(External, 1, AttrUnknown);
else
SetBuilder.addAttributesBelow(External, 1, AttrCaller);
}
}
// Special handling for interprocedural aliases
for (auto &Edge : GraphBuilder.getInterprocEdges()) {
auto FromVal = Edge.From.Val;
auto ToVal = Edge.To.Val;
SetBuilder.add(FromVal);
SetBuilder.add(ToVal);
SetBuilder.addBelowWith(FromVal, Edge.From.DerefLevel, ToVal,
Edge.To.DerefLevel);
}
// Special handling for interprocedural attributes
for (auto &IPAttr : GraphBuilder.getInterprocAttrs()) {
auto Val = IPAttr.Node.Val;
SetBuilder.add(Val);
SetBuilder.addAttributesBelow(Val, IPAttr.Node.DerefLevel, IPAttr.Attr);
}
// Special handling for opaque external functions
for (auto *Escape : GraphBuilder.getEscapedValues()) {
SetBuilder.add(Escape);
SetBuilder.noteAttributes(Escape, AttrEscaped);
SetBuilder.addAttributesBelow(Escape, 1, AttrUnknown);
}
return FunctionInfo(*Fn, GraphBuilder.getReturnValues(), SetBuilder.build());
}
