struct OutlinableRegion

Declaration

struct OutlinableRegion { /* full declaration omitted */ };

Description

The OutlinableRegion holds all the information for a specific region, or sequence of instructions. This includes what values need to be hoisted to arguments from the extracted function, inputs and outputs to the region, and mapping from the extracted function arguments to overall function arguments.

Declared at: llvm/include/llvm/Transforms/IPO/IROutliner.h:63

Member Variables

public llvm::IRSimilarity::IRSimilarityCandidate* Candidate = nullptr
Describes the region of code.
public llvm::IRSimilarity::IRInstructionData* NewFront = nullptr
If this region is outlined, the front and back IRInstructionData could potentially become invalidated if the only new instruction is a call. This ensures that we replace in the instruction in the IRInstructionData.
public llvm::IRSimilarity::IRInstructionData* NewBack = nullptr
public unsigned int NumExtractedInputs = 0
The number of extracted inputs from the CodeExtractor.
public unsigned int OutputBlockNum = -1
The corresponding BasicBlock with the appropriate stores for this OutlinableRegion in the overall function.
public DenseMap<unsigned int, unsigned int> ExtractedArgToAgg
Mapping the extracted argument number to the argument number in the overall function. Since there will be inputs, such as elevated constants that are not the same in each region in a SimilarityGroup, or values that cannot be sunk into the extracted section in every region, we must keep track of which extracted argument maps to which overall argument.
public DenseMap<unsigned int, unsigned int> AggArgToExtracted
public DenseMap<llvm::Value*, llvm::Value*> RemappedArguments
Values in the outlined functions will often be replaced by arguments. When finding corresponding values from one region to another, the found value will be the value the argument previously replaced. This structure maps any replaced values for the region to the aggregate aggregate argument in the overall function.
public bool ChangedArgOrder = false
Marks whether we need to change the order of the arguments when mapping the old extracted function call to the new aggregate outlined function call.
public bool EndsInBranch = false
Marks whether this region ends in a branch, there is special handling required for the following basic blocks in this case.
public DenseMap<llvm::Value*, llvm::BasicBlock*> PHIBlocks
The PHIBlocks with their corresponding return block based on the return value as the key.
public DenseMap<unsigned int, llvm::Constant*> AggArgToConstant
Mapping of the argument number in the deduplicated function to a given constant, which is used when creating the arguments to the call to the newly created deduplicated function. This is handled separately since the CodeExtractor does not recognize constants.
public SmallVector<unsigned int, 4> GVNStores
The global value numbers that are used as outputs for this section. Once extracted, each output will be stored to an output register. This documents the global value numbers that are used in this pattern.
public llvm::CodeExtractor* CE = nullptr
Used to create an outlined function.
public llvm::CallInst* Call = nullptr
The call site of the extracted region.
public llvm::Function* ExtractedFunction = nullptr
The function for the extracted region.
public bool CandidateSplit = false
Flag for whether we have split out the IRSimilarityCanidate. That is, make the region contained the IRSimilarityCandidate its own BasicBlock.
public bool IgnoreRegion = false
Flag for whether we should not consider this region for extraction.
public llvm::BasicBlock* PrevBB = nullptr
The BasicBlock that is before the start of the region BasicBlock, only defined when the region has been split.
public llvm::BasicBlock* StartBB = nullptr
The BasicBlock that contains the starting instruction of the region.
public llvm::BasicBlock* EndBB = nullptr
The BasicBlock that contains the ending instruction of the region.
public llvm::BasicBlock* FollowBB = nullptr
The BasicBlock that is after the start of the region BasicBlock, only defined when the region has been split.
public OutlinableGroup* Parent = nullptr
The Outlinable Group that contains this region and structurally similar regions to this region.

Method Overview

Methods

OutlinableRegion(
    llvm::IRSimilarity::IRSimilarityCandidate& C,
    OutlinableGroup& Group)

Declared at: llvm/include/llvm/Transforms/IPO/IROutliner.h:153

Parameters

llvm::IRSimilarity::IRSimilarityCandidate& C
OutlinableGroup& Group

llvm::BasicBlock* findCorrespondingBlockIn(
    const llvm::OutlinableRegion& Other,
    llvm::BasicBlock* BB)

Description

Find a corresponding BasicBlock for \p BB in similar OutlinableRegion \p Other.

Declared at: llvm/include/llvm/Transforms/IPO/IROutliner.h:183

Parameters

const llvm::OutlinableRegion& Other
[in] - The OutlinableRegion to find the corresponding BasicBlock in.
llvm::BasicBlock* BB
[in] - The BasicBlock to look for in the other region.

Returns

The corresponding Value to \p V if it exists, otherwise nullptr.

llvm::Value* findCorrespondingValueIn(
    const llvm::OutlinableRegion& Other,
    llvm::Value* V)

Description

Find a corresponding value for \p V in similar OutlinableRegion \p Other.

Declared at: llvm/include/llvm/Transforms/IPO/IROutliner.h:175

Parameters

const llvm::OutlinableRegion& Other
[in] - The OutlinableRegion to find the corresponding Value in.
llvm::Value* V
[in] - The Value to look for in the other region.

Returns

The corresponding Value to \p V if it exists, otherwise nullptr.

llvm::InstructionCost getBenefit(
    llvm::TargetTransformInfo& TTI)

Description

Get the size of the code removed from the region.

Declared at: llvm/include/llvm/Transforms/IPO/IROutliner.h:190

Parameters

llvm::TargetTransformInfo& TTI
- The TargetTransformInfo for the parent function.

Returns

the code size of the region

void reattachCandidate()

Description

For the contained region, reattach the BasicBlock at the starting and ending instructions of the contained IRSimilarityCandidate, or if the function has been extracted, the start and end of the BasicBlock containing the called function.

Declared at: llvm/include/llvm/Transforms/IPO/IROutliner.h:167

void splitCandidate()

Description

For the contained region, split the parent BasicBlock at the starting and ending instructions of the contained IRSimilarityCandidate.

Declared at: llvm/include/llvm/Transforms/IPO/IROutliner.h:161