bool AllowIdenticalEdges = false);
/// SplitCriticalEdge - If this edge is a critical edge, insert a new node to
-/// split the critical edge. This will update ETForest, ImmediateDominator,
-/// DominatorTree, and DominatorFrontier information if it is available, thus
-/// calling this pass will not invalidate either of them. This returns true if
-/// the edge was split, false otherwise. If MergeIdenticalEdges is true (the
-/// default), *all* edges from TI to the specified successor will be merged into
-/// the same critical edge block. This is most commonly interesting with switch
-/// instructions, which may have many edges to any one destination. This
-/// ensures that all edges to that dest go to one block instead of each going to
-/// a different block, but isn't the standard definition of a "critical edge".
+/// split the critical edge. This will update DominatorTree, and DominatorFrontier
+/// information if it is available, thus calling this pass will not invalidate
+/// either of them. This returns true if the edge was split, false otherwise.
+/// If MergeIdenticalEdges is true (the default), *all* edges from TI to the
+/// specified successor will be merged into the same critical edge block.
+/// This is most commonly interesting with switch instructions, which may
+/// have many edges to any one destination. This ensures that all edges to that
+/// dest go to one block instead of each going to a different block, but isn't
+/// the standard definition of a "critical edge".
///
bool SplitCriticalEdge(TerminatorInst *TI, unsigned SuccNum, Pass *P = 0,
bool MergeIdenticalEdges = false);
virtual bool runOnFunction(Function &F);
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
- AU.addPreserved<ETForest>();
AU.addPreserved<DominatorTree>();
AU.addPreserved<DominanceFrontier>();
AU.addPreserved<LoopInfo>();
}
// SplitCriticalEdge - If this edge is a critical edge, insert a new node to
-// split the critical edge. This will update ETForest, ImmediateDominator,
-// DominatorTree, and DominatorFrontier information if it is available, thus
-// calling this pass will not invalidate any of them. This returns true if
-// the edge was split, false otherwise. This ensures that all edges to that
-// dest go to one block instead of each going to a different block.
+// split the critical edge. This will update DominatorTree, and DominatorFrontier
+// information if it is available, thus calling this pass will not invalidate
+// any of them. This returns true if the edge was split, false otherwise.
+// This ensures that all edges to that dest go to one block instead of each
+// going to a different block.
//
bool llvm::SplitCriticalEdge(TerminatorInst *TI, unsigned SuccNum, Pass *P,
bool MergeIdenticalEdges) {
bool NewBBDominatesDestBB = true;
- // Update the forest?
- if (ETForest *EF = P->getAnalysisToUpdate<ETForest>()) {
- // NewBB is dominated by TIBB.
- EF->addNewBlock(NewBB, TIBB);
-
- // If NewBBDominatesDestBB hasn't been computed yet, do so with EF.
- if (!OtherPreds.empty()) {
- while (!OtherPreds.empty() && NewBBDominatesDestBB) {
- NewBBDominatesDestBB = EF->dominates(DestBB, OtherPreds.back());
- OtherPreds.pop_back();
- }
- OtherPreds.clear();
- }
-
- // If NewBBDominatesDestBB, then NewBB dominates DestBB, otherwise it
- // doesn't dominate anything.
- if (NewBBDominatesDestBB)
- EF->setImmediateDominator(DestBB, NewBB);
- }
-
// Should we update DominatorTree information?
if (DominatorTree *DT = P->getAnalysisToUpdate<DominatorTree>()) {
DomTreeNode *TINode = DT->getNode(TIBB);