RegioInfo: Add getExpandedRegion().
getExpandedRegion() enables us to create non canonical regions. Those regions
can be used to define the largerst region, that fullfills a certain property.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116397 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/Analysis/RegionInfo.h b/include/llvm/Analysis/RegionInfo.h
index 1626abb..f982b9f 100644
--- a/include/llvm/Analysis/RegionInfo.h
+++ b/include/llvm/Analysis/RegionInfo.h
@@ -292,6 +292,14 @@
/// @return The depth of the region.
unsigned getDepth() const;
+ /// @brief Return a new (non canonical) region, that is obtained by joining
+ /// this region with its predecessors.
+ ///
+ /// @return A region also starting at getEntry(), but reaching to the next
+ /// basic block that forms with getEntry() a (non canonical) region.
+ /// NULL if such a basic block does not exist.
+ Region *getExpandedRegion() const;
+
/// @brief Is this a simple region?
///
/// A region is simple if it has exactly one exit and one entry edge.
diff --git a/lib/Analysis/RegionInfo.cpp b/lib/Analysis/RegionInfo.cpp
index 0bf6aad..2576d4e 100644
--- a/lib/Analysis/RegionInfo.cpp
+++ b/lib/Analysis/RegionInfo.cpp
@@ -373,6 +373,38 @@
return Depth;
}
+Region *Region::getExpandedRegion() const {
+ unsigned NumSuccessors = exit->getTerminator()->getNumSuccessors();
+
+ if (NumSuccessors == 0)
+ return NULL;
+
+ for (pred_iterator PI = pred_begin(getExit()), PE = pred_end(getExit());
+ PI != PE; ++PI)
+ if (!DT->dominates(getEntry(), *PI))
+ return NULL;
+
+ Region *R = RI->getRegionFor(exit);
+
+ if (R->getEntry() != exit) {
+ if (exit->getTerminator()->getNumSuccessors() == 1)
+ return new Region(getEntry(), *succ_begin(exit), RI, DT);
+ else
+ return NULL;
+ }
+
+ while (R->getParent() && R->getParent()->getEntry() == exit)
+ R = R->getParent();
+
+ if (!DT->dominates(getEntry(), R->getExit()))
+ for (pred_iterator PI = pred_begin(getExit()), PE = pred_end(getExit());
+ PI != PE; ++PI)
+ if (!DT->dominates(R->getExit(), *PI))
+ return NULL;
+
+ return new Region(getEntry(), R->getExit(), RI, DT);
+}
+
void Region::print(raw_ostream &OS, bool print_tree, unsigned level) const {
if (print_tree)
OS.indent(level*2) << "[" << level << "] " << getNameStr();