Class GreedyRegisterAllocator<TRegister>

An analysis that greedily allocates registers to values. The set of values is assumed to be unbounded: the analysis is allowed to "create" an arbitrarily large amount of registers.

Inheritance

object

GreedyRegisterAllocator<TRegister>

Implements

IFlowGraphAnalysis<RegisterAllocation<TRegister>>

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: Flame.Compiler.Analysis

Assembly: Flame.Compiler.dll

Syntax

public abstract class GreedyRegisterAllocator<TRegister> : IFlowGraphAnalysis<RegisterAllocation<TRegister>>

Type Parameters

Name	Description
TRegister	The type of register allocated to values.

Methods

Analyze(FlowGraph)

Analyzes a flow graph from scratch.

Declaration

public RegisterAllocation<TRegister> Analyze(FlowGraph graph)

Parameters

Type	Name	Description
FlowGraph	graph	The flow graph to analyze.

Returns

Type	Description
RegisterAllocation<TRegister>	The analysis' output.

AnalyzeWithUpdates(FlowGraph, RegisterAllocation<TRegister>, IReadOnlyList<FlowGraphUpdate>)

Analyzes a flow graph based on the flow graph, the previous result, and a list of updates that were applied to the graph since the previous result.

Declaration

public RegisterAllocation<TRegister> AnalyzeWithUpdates(FlowGraph graph, RegisterAllocation<TRegister> previousResult, IReadOnlyList<FlowGraphUpdate> updates)

Parameters

Type	Name	Description
FlowGraph	graph	The current version of the flow graph to analyze.
RegisterAllocation<TRegister>	previousResult	A previous result produced by this analysis.
IReadOnlyList<FlowGraphUpdate>	updates	A list of updates that were applied to the flow graph since the previous result was computed.

Returns

Type	Description
RegisterAllocation<TRegister>	The analysis' output, which must be equal to a call to Analyze.

CreateRegister(IType)

Creates a brand new register for a value of a particular type.

Declaration

protected abstract TRegister CreateRegister(IType type)

Parameters

Type	Name	Description
IType	type	The type of value to create a register for.

Returns

Type	Description
TRegister	A register suitable for the value.

RequiresRegister(ValueTag, FlowGraph)

Tells if a register should be allocated for a particular value.

Declaration

protected virtual bool RequiresRegister(ValueTag value, FlowGraph graph)

Parameters

Type	Name	Description
ValueTag	value	The value for which register allocation may or may not be necessary.
FlowGraph	graph	The control flow graph that defines value.

Returns

Type	Description
bool	true if a register must be allocated to value; otherwise, false.

Remarks

Implementations may override this method to suppress register allocation for values that are, e.g., stored on an evaluation stack.

TryGetPreallocatedRegister(ValueTag, FlowGraph, out TRegister)

Tries to get a preallocated register for a particular value. If it exists, then the preallocated register will be used for the value, no questions asked. The preallocated register may be reused.

Declaration

protected virtual bool TryGetPreallocatedRegister(ValueTag value, FlowGraph graph, out TRegister register)

Parameters

Type	Name	Description
ValueTag	value	The value that may have a preallocated register.
FlowGraph	graph	The graph that defines the value.
TRegister	register	A preallocated register, if any.

Returns

Type	Description
bool	true if there is a preallocated register for value; otherwise, false.

TryRecycleRegister(IType, IEnumerable<TRegister>, out TRegister)

Tries to recycle a register from a set of registers.

Declaration

protected abstract bool TryRecycleRegister(IType type, IEnumerable<TRegister> registers, out TRegister result)

Parameters

Type	Name	Description
IType	type	The type of value to store in the recycled register.
IEnumerable<TRegister>	registers	A set of registers that are eligible for recycling.
TRegister	result	A register to recycle, if any.

Returns

Type	Description
bool	true if a register has been selected for recyling; otherwise, false.

Implements

IFlowGraphAnalysis<T>