add a new Region::block_iterator which actually iterates over the basic
blocks of the region.
The old iterator, now call 'block_node_iterator' iterates over
RegionNodes which contain a single basic block. This works well with the
GraphTraits-based iterator design, however most users actually want an
iterator over the BasicBlocks inside these RegionNodes. Now the
'block_iterator' is a wrapper which exposes exactly this interface.
Internally it uses the block_node_iterator to walk all nodes which are
single basic blocks, but transparently unwraps the basic block to make
user code simpler.
While this patch is a bit of a wash, most of the updates are to internal
users, not external users of the RegionInfo. I have an accompanying
patch to Polly that is a strict simplification of every user of this
interface, and I'm working on a pass that also wants the same simplified
interface.
This patch alone should have no functional impact.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156202 91177308-0d34-0410-b5e6-96231b3b80d8
Add methods for accessing the (single) entry / exit edge of a region. If no such
edge exists, null is returned. Both accessors return the start block of the
corresponding edge. The edge can finally be formed by utilizing
Region::getEntry() or Region::getExit();
Contributed by: Andreas Simbuerger <simbuerg@fim.uni-passau.de>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123410 91177308-0d34-0410-b5e6-96231b3b80d8
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
* contains(Loop), * getOutermostLoop()
* Improve getNameStr() to return a sensible name, if basic blocks are not named.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109490 91177308-0d34-0410-b5e6-96231b3b80d8
The RegionInfo pass detects single entry single exit regions in a function,
where a region is defined as any subgraph that is connected to the remaining
graph at only two spots.
Furthermore an hierarchical region tree is built.
Use it by calling "opt -regions analyze" or "opt -view-regions".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109089 91177308-0d34-0410-b5e6-96231b3b80d8
