+void SCCPSolver::visitExtractValueInst(ExtractValueInst &EVI) {
+ Value *Aggr = EVI.getAggregateOperand();
+
+ // If the operand to the extractvalue is an undef, the result is undef.
+ if (isa<UndefValue>(Aggr))
+ return;
+
+ // Currently only handle single-index extractvalues.
+ if (EVI.getNumIndices() != 1) {
+ markOverdefined(&EVI);
+ return;
+ }
+
+ Function *F = 0;
+ if (CallInst *CI = dyn_cast<CallInst>(Aggr))
+ F = CI->getCalledFunction();
+ else if (InvokeInst *II = dyn_cast<InvokeInst>(Aggr))
+ F = II->getCalledFunction();
+
+ // TODO: If IPSCCP resolves the callee of this function, we could propagate a
+ // result back!
+ if (F == 0 || TrackedMultipleRetVals.empty()) {
+ markOverdefined(&EVI);
+ return;
+ }
+
+ // See if we are tracking the result of the callee. If not tracking this
+ // function (for example, it is a declaration) just move to overdefined.
+ if (!TrackedMultipleRetVals.count(std::make_pair(F, *EVI.idx_begin()))) {
+ markOverdefined(&EVI);
+ return;
+ }
+
+ // Otherwise, the value will be merged in here as a result of CallSite
+ // handling.
+}
+
+void SCCPSolver::visitInsertValueInst(InsertValueInst &IVI) {
+ Value *Aggr = IVI.getAggregateOperand();
+ Value *Val = IVI.getInsertedValueOperand();
+
+ // If the operands to the insertvalue are undef, the result is undef.
+ if (isa<UndefValue>(Aggr) && isa<UndefValue>(Val))
+ return;
+
+ // Currently only handle single-index insertvalues.
+ if (IVI.getNumIndices() != 1) {
+ markOverdefined(&IVI);
+ return;
+ }
+
+ // Currently only handle insertvalue instructions that are in a single-use
+ // chain that builds up a return value.
+ for (const InsertValueInst *TmpIVI = &IVI; ; ) {
+ if (!TmpIVI->hasOneUse()) {
+ markOverdefined(&IVI);
+ return;
+ }
+ const Value *V = *TmpIVI->use_begin();
+ if (isa<ReturnInst>(V))
+ break;
+ TmpIVI = dyn_cast<InsertValueInst>(V);
+ if (!TmpIVI) {
+ markOverdefined(&IVI);
+ return;
+ }
+ }
+
+ // See if we are tracking the result of the callee.
+ Function *F = IVI.getParent()->getParent();
+ DenseMap<std::pair<Function*, unsigned>, LatticeVal>::iterator
+ It = TrackedMultipleRetVals.find(std::make_pair(F, *IVI.idx_begin()));
+
+ // Merge in the inserted member value.
+ if (It != TrackedMultipleRetVals.end())
+ mergeInValue(It->second, F, getValueState(Val));
+
+ // Mark the aggregate result of the IVI overdefined; any tracking that we do
+ // will be done on the individual member values.
+ markOverdefined(&IVI);
+}
+