class RegionBase

Declaration

template <class Tr>
class RegionBase { /* full declaration omitted */ };

Description

A single entry single exit Region. A Region is a connected subgraph of a control flow graph that has exactly two connections to the remaining graph. It can be used to analyze or optimize parts of the control flow graph. A simple Region is connected to the remaining graph by just two edges. One edge entering the Region and another one leaving the Region. An extended Region (or just Region) is a subgraph that can be transform into a simple Region. The transformation is done by adding BasicBlocks that merge several entry or exit edges so that after the merge just one entry and one exit edge exists. The \e Entry of a Region is the first BasicBlock that is passed after entering the Region. It is an element of the Region. The entry BasicBlock dominates all BasicBlocks in the Region. The \e Exit of a Region is the first BasicBlock that is passed after leaving the Region. It is not an element of the Region. The exit BasicBlock, postdominates all BasicBlocks in the Region. A canonical Region cannot be constructed by combining smaller Regions. Region A is the \e parent of Region B, if B is completely contained in A. Two canonical Regions either do not intersect at all or one is the parent of the other. The Program Structure Tree is a graph (V, E) where V is the set of Regions in the control flow graph and E is the \e parent relation of these Regions. Example: You can obtain more examples by either calling "opt -regions -analyze anyprogram.ll" or "opt -view-regions-only anyprogram.ll" on any LLVM file you are interested in. The first call returns a textual representation of the program structure tree, the second one creates a graphical representation using graphviz.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:255

Templates

Tr

Method Overview

• public RegionBase<RegionTr>(const RegionBase<RegionTr> &)
• public RegionBase<RegionTr>(llvm::RegionBase::BlockT * Entry, llvm::RegionBase::BlockT * Exit, llvm::RegionBase::RegionInfoT * RI, llvm::RegionBase::DomTreeT * DT, llvm::RegionBase::RegionT * Parent = nullptr)
• public void addSubRegion(llvm::RegionBase::RegionT * SubRegion, bool moveChildren = false)
• public llvm::RegionBase::iterator begin()
• public llvm::RegionBase::const_iterator begin() const
• public llvm::RegionBase::const_block_iterator block_begin() const
• public llvm::RegionBase::block_iterator block_begin()
• public llvm::RegionBase::const_block_iterator block_end() const
• public llvm::RegionBase::block_iterator block_end()
• public inline llvm::RegionBase::const_block_range blocks() const
• public inline llvm::RegionBase::block_range blocks()
• public void clearNodeCache()
• public bool contains(const llvm::RegionBase::LoopT * L) const
• public bool contains(const llvm::RegionBase::InstT * Inst) const
• public bool contains(const llvm::RegionBase::RegionT * SubRegion) const
• public bool contains(const llvm::RegionBase::BlockT * BB) const
• public void dump() const
• public llvm::RegionBase::element_iterator element_begin()
• public llvm::RegionBase::const_element_iterator element_begin() const
• public llvm::RegionBase::element_iterator element_end()
• public llvm::RegionBase::const_element_iterator element_end() const
• public iterator_range<llvm::RegionBase::const_element_iterator> elements() const
• public iterator_range<llvm::RegionBase::element_iterator> elements()
• public llvm::RegionBase::const_iterator end() const
• public llvm::RegionBase::iterator end()
• public llvm::RegionBase::RegionNodeT * getBBNode(llvm::RegionBase::BlockT * BB) const
• public unsigned int getDepth() const
• public llvm::RegionBase::BlockT * getEnteringBlock() const
• public llvm::RegionBase::BlockT * getEntry() const
• public llvm::RegionBase::BlockT * getExit() const
• public llvm::RegionBase::BlockT * getExitingBlock() const
• public bool getExitingBlocks(SmallVectorImpl<llvm::RegionBase::BlockT *> & Exitings) const
• public llvm::RegionBase::RegionT * getExpandedRegion() const
• public std::string getNameStr() const
• public llvm::RegionBase::RegionNodeT * getNode() const
• public llvm::RegionBase::RegionNodeT * getNode(llvm::RegionBase::BlockT * BB) const
• public llvm::RegionBase::RegionT * getParent() const
• public llvm::RegionBase::RegionInfoT * getRegionInfo() const
• public llvm::RegionBase::RegionT * getSubRegionNode(llvm::RegionBase::BlockT * BB) const
• public bool isSimple() const
• public bool isTopLevelRegion() const
• public llvm::RegionBase::LoopT * outermostLoopInRegion(llvm::RegionBase::LoopInfoT * LI, llvm::RegionBase::BlockT * BB) const
• public llvm::RegionBase::LoopT * outermostLoopInRegion(llvm::RegionBase::LoopT * L) const
• public void print(llvm::raw_ostream & OS, bool printTree = true, unsigned int level = 0, llvm::RegionBase::PrintStyle Style = PrintNone) const
• public llvm::RegionBase::RegionT * removeSubRegion(llvm::RegionBase::RegionT * SubRegion)
• public void replaceEntry(llvm::RegionBase::BlockT * BB)
• public void replaceEntryRecursive(llvm::RegionBase::BlockT * NewEntry)
• public void replaceExit(llvm::RegionBase::BlockT * BB)
• public void replaceExitRecursive(llvm::RegionBase::BlockT * NewExit)
• public void transferChildrenTo(llvm::RegionBase::RegionT * To)
• public void verifyRegion() const
• public ~RegionBase<RegionTr>()

Methods

¶RegionBase<RegionTr>(const RegionBase<RegionTr>&)

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:315

Parameters

const RegionBase<RegionTr>&

¶RegionBase<RegionTr>(
    llvm::RegionBase::BlockT* Entry,
    llvm::RegionBase::BlockT* Exit,
    llvm::RegionBase::RegionInfoT* RI,
    llvm::RegionBase::DomTreeT* DT,
    llvm::RegionBase::RegionT* Parent = nullptr)

Description

Create a new region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:312

Parameters

llvm::RegionBase::BlockT* Entry

The entry basic block of the region.

llvm::RegionBase::BlockT* Exit

The exit basic block of the region.

llvm::RegionBase::RegionInfoT* RI

The region info object that is managing this region.

llvm::RegionBase::DomTreeT* DT

The dominator tree of the current function.

llvm::RegionBase::RegionT* Parent = nullptr

The surrounding region or NULL if this is a top level region.

¶void addSubRegion(
    llvm::RegionBase::RegionT* SubRegion,
    bool moveChildren = false)

Description

Add a new subregion to this Region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:527

Parameters

llvm::RegionBase::RegionT* SubRegion

The new subregion that will be added.

bool moveChildren = false

Move the children of this region, that are also contained in SubRegion into SubRegion.

¶llvm::RegionBase::iterator begin()

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:561

¶llvm::RegionBase::const_iterator begin() const

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:564

¶llvm::RegionBase::const_block_iterator
block_begin() const

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:615

¶llvm::RegionBase::block_iterator block_begin()

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:611

¶llvm::RegionBase::const_block_iterator block_end()
    const

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:618

¶llvm::RegionBase::block_iterator block_end()

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:613

¶inline llvm::RegionBase::const_block_range
blocks() const

Description

Returns a range view of the basic blocks in the region. This is the 'const' version of the range view.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:631

¶inline llvm::RegionBase::block_range blocks()

Description

Returns a range view of the basic blocks in the region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:624

¶void clearNodeCache()

Description

Clear the cache for BB RegionNodes. After calling this function the BasicBlock RegionNodes will be stored at different memory locations. RegionNodes obtained before this function is called are therefore not comparable to RegionNodes abtained afterwords.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:552

¶bool contains(
    const llvm::RegionBase::LoopT* L) const

Description

Check if the region contains a loop.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:479

Parameters

const llvm::RegionBase::LoopT* L

The loop that might be contained in this region.

Returns

True if the loop is contained in the region otherwise false. In case a NULL pointer is passed to this function the result is false, except for the region that describes the whole function. In that case true is returned.

¶bool contains(
    const llvm::RegionBase::InstT* Inst) const

Description

Check if the region contains an Instruction.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:470

Parameters

const llvm::RegionBase::InstT* Inst

The Instruction that might be contained in this region.

Returns

True if the Instruction is contained in the region otherwise false.

¶bool contains(const llvm::RegionBase::RegionT*
                  SubRegion) const

Description

Check if the region contains another region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:455

Parameters

const llvm::RegionBase::RegionT* SubRegion

The region that might be contained in this Region.

Returns

True if SubRegion is contained in the region otherwise false.

¶bool contains(
    const llvm::RegionBase::BlockT* BB) const

Description

Check if the region contains a BasicBlock.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:449

Parameters

const llvm::RegionBase::BlockT* BB

The BasicBlock that might be contained in this Region.

Returns

True if the block is contained in the region otherwise false.

¶void dump() const

Description

Print the region to stderr.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:442

¶llvm::RegionBase::element_iterator element_begin()

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:651

¶llvm::RegionBase::const_element_iterator
element_begin() const

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:657

¶llvm::RegionBase::element_iterator element_end()

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:652

¶llvm::RegionBase::const_element_iterator
element_end() const

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:658

¶iterator_range<
    llvm::RegionBase::const_element_iterator>
elements() const

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:659

¶iterator_range<llvm::RegionBase::element_iterator>
elements()

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:653

¶llvm::RegionBase::const_iterator end() const

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:565

¶llvm::RegionBase::iterator end()

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:562

¶llvm::RegionBase::RegionNodeT* getBBNode(
    llvm::RegionBase::BlockT* BB) const

Description

Get the BasicBlock RegionNode for a BasicBlock

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:520

Parameters

llvm::RegionBase::BlockT* BB

The BasicBlock for which the RegionNode is requested.

Returns

The RegionNode representing the BB.

¶unsigned int getDepth() const

Description

Get the nesting level of this Region. An toplevel Region has depth 0.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:381

Returns

The depth of the region.

¶llvm::RegionBase::BlockT* getEnteringBlock() const

Description

Return the first block of this region's single entry edge, if existing.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:401

Returns

The BasicBlock starting this region's single entry edge, else NULL.

¶llvm::RegionBase::BlockT* getEntry() const

Description

Get the entry BasicBlock of the Region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:323

Returns

The entry BasicBlock of the region.

¶llvm::RegionBase::BlockT* getExit() const

Description

Get the exit BasicBlock of the Region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:360

Returns

The exit BasicBlock of the Region, NULL if this is the TopLevel Region.

¶llvm::RegionBase::BlockT* getExitingBlock() const

Description

Return the first block of this region's single exit edge, if existing.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:408

Returns

The BasicBlock starting this region's single exit edge, else NULL.

¶bool getExitingBlocks(
    SmallVectorImpl<llvm::RegionBase::BlockT*>&
        Exitings) const

Description

Collect all blocks of this region's single exit edge, if existing.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:413

Parameters

SmallVectorImpl<llvm::RegionBase::BlockT*>& Exitings

Returns

True if this region contains all the predecessors of the exit.

¶llvm::RegionBase::RegionT* getExpandedRegion()
    const

Description

Return a new (non-canonical) region, that is obtained by joining this region with its predecessors.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:394

Returns

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.

¶std::string getNameStr() const

Description

Returns the name of the Region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:424

Returns

The Name of the Region.

¶llvm::RegionBase::RegionNodeT* getNode() const

Description

Get the RegionNode representing the current Region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:371

Returns

The RegionNode representing the current Region.

¶llvm::RegionBase::RegionNodeT* getNode(
    llvm::RegionBase::BlockT* BB) const

Description

Get the RegionNode for a BasicBlock

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:514

Parameters

llvm::RegionBase::BlockT* BB

The BasicBlock at which the RegionNode should start.

Returns

If available, the RegionNode that represents the subregion starting at BB. If no subregion starts at BB, the RegionNode representing BB.

¶llvm::RegionBase::RegionT* getParent() const

Description

Get the parent of the Region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:365

Returns

The parent of the Region or NULL if this is a top level Region.

¶llvm::RegionBase::RegionInfoT* getRegionInfo()
    const

Description

Return the RegionInfo object, that belongs to this Region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:427

¶llvm::RegionBase::RegionT* getSubRegionNode(
    llvm::RegionBase::BlockT* BB) const

Description

Get the subregion that starts at a BasicBlock

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:506

Parameters

llvm::RegionBase::BlockT* BB

The BasicBlock the subregion should start.

Returns

The Subregion if available, otherwise NULL.

¶bool isSimple() const

Description

Is this a simple region? A region is simple if it has exactly one exit and one entry edge.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:420

Returns

True if the Region is simple.

¶bool isTopLevelRegion() const

Description

Check if a Region is the TopLevel region. The toplevel region represents the whole function.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:386

¶llvm::RegionBase::LoopT* outermostLoopInRegion(
    llvm::RegionBase::LoopInfoT* LI,
    llvm::RegionBase::BlockT* BB) const

Description

Get the outermost loop in the region that contains a basic block. Find for a basic block BB the outermost loop L that contains BB and is itself contained in the region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:500

Parameters

llvm::RegionBase::LoopInfoT* LI

A pointer to a LoopInfo analysis.

llvm::RegionBase::BlockT* BB

The basic block surrounded by the loop.

Returns

The outermost loop in the region, NULL if such a loop does not exist or if the region describes the whole function.

¶llvm::RegionBase::LoopT* outermostLoopInRegion(
    llvm::RegionBase::LoopT* L) const

Description

Get the outermost loop in the region that contains a loop. Find for a Loop L the outermost loop OuterL that is a parent loop of L and is itself contained in the region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:489

Parameters

llvm::RegionBase::LoopT* L

The loop the lookup is started.

Returns

The outermost loop in the region, NULL if such a loop does not exist or if the region describes the whole function.

¶void print(llvm::raw_ostream& OS,
           bool printTree = true,
           unsigned int level = 0,
           llvm::RegionBase::PrintStyle Style =
               PrintNone) const

Description

Print the region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:437

Parameters

llvm::raw_ostream& OS

The output stream the Region is printed to.

bool printTree = true

Print also the tree of subregions.

unsigned int level = 0

The indentation level used for printing.

llvm::RegionBase::PrintStyle Style = PrintNone

¶llvm::RegionBase::RegionT* removeSubRegion(
    llvm::RegionBase::RegionT* SubRegion)

Description

Remove a subregion from this Region. The subregion is not deleted, as it will probably be inserted into another region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:534

Parameters

llvm::RegionBase::RegionT* SubRegion

The SubRegion that will be removed.

¶void replaceEntry(llvm::RegionBase::BlockT* BB)

Description

Replace the entry basic block of the region with the new basic block.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:331

Parameters

llvm::RegionBase::BlockT* BB

The new entry basic block of the region.

¶void replaceEntryRecursive(
    llvm::RegionBase::BlockT* NewEntry)

Description

Recursively replace the entry basic block of the region. This function replaces the entry basic block with a new basic block. It also updates all child regions that have the same entry basic block as this region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:346

Parameters

llvm::RegionBase::BlockT* NewEntry

The new entry basic block.

¶void replaceExit(llvm::RegionBase::BlockT* BB)

Description

Replace the exit basic block of the region with the new basic block.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:337

Parameters

llvm::RegionBase::BlockT* BB

The new exit basic block of the region.

¶void replaceExitRecursive(
    llvm::RegionBase::BlockT* NewExit)

Description

Recursively replace the exit basic block of the region. This function replaces the exit basic block with a new basic block. It also updates all child regions that have the same exit basic block as this region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:355

Parameters

llvm::RegionBase::BlockT* NewExit

The new exit basic block.

¶void transferChildrenTo(
    llvm::RegionBase::RegionT* To)

Description

Move all direct child nodes of this Region to another Region.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:539

Parameters

llvm::RegionBase::RegionT* To

The Region the child nodes will be transferred to.

¶void verifyRegion() const

Description

Verify if the region is a correct region. Check if this is a correctly build Region. This is an expensive check, as the complete CFG of the Region will be walked.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:545

¶~RegionBase<RegionTr>()

Description

Delete the Region and all its subregions.

Declared at: llvm/include/llvm/Analysis/RegionInfo.h:319