org.apache.drill.exec.compile.bytecode

Class ReplacingBasicValue

java.lang.Object

org.objectweb.asm.tree.analysis.BasicValue

org.apache.drill.exec.compile.bytecode.ReplacingBasicValue

All Implemented Interfaces:

org.objectweb.asm.tree.analysis.Value

public class ReplacingBasicValue
extends org.objectweb.asm.tree.analysis.BasicValue

BasicValue with additional tracking information used to determine the replaceability of the value (a holder, or boxed value) for scalar replacement purposes.

Contains a set of flags that indicate how the value is used. These are updated throughout the life of the function, via the Analyzer/Interpreter, which simulate execution of the function. After the analysis is complete, the flags indicate how the value/variable was used, and that in turn indicates whether or not we can replace it.

Field Summary

Fields inherited from class org.objectweb.asm.tree.analysis.BasicValue

DOUBLE_VALUE, FLOAT_VALUE, INT_VALUE, LONG_VALUE, REFERENCE_VALUE, RETURNADDRESS_VALUE, UNINITIALIZED_VALUE

Method Summary

Methods

Modifier and Type	Method and Description
void	associate(ReplacingBasicValue other) Associate this value with another.
static ReplacingBasicValue	create(org.objectweb.asm.Type type, org.apache.drill.exec.compile.bytecode.ValueHolderIden iden, int index, List<ReplacingBasicValue> valueList) Create a new value representing a holder (boxed value).
void	disableFunctionReturn() Clear the indication that this value is used as a function return value.
void	dump(StringBuilder sb, int indentLevel) Dump the value's members to a StringBuilder.
org.apache.drill.exec.compile.bytecode.ValueHolderIden	getIden() Return the ValueHolder identity for this value.
int	getIndex() Get the original local variable slot assigned to this value/holder.
boolean	isAssignedToMember() Indicates whether or not this value is assigned to a class member variable.
boolean	isFunctionArgument() Indicates whether or not this value is used as a function argument.
boolean	isFunctionReturn() Indicates whether or not this value is used as a function return value.
boolean	isReplaceable() Indicates whether or not this value is replaceable.
boolean	isThis() Indicates whether or not this value is a "this" reference.
void	markFunctionReturn() Mark this value as being used as a function return value.
void	setAssignedToMember() Mark this value as being assigned to a class member variable.
void	setFrameSlot(int frameSlot)
void	setFunctionArgument() Mark this value as being used as a function argument.
void	setThis() Mark this value as a "this" reference.

Methods inherited from class org.objectweb.asm.tree.analysis.BasicValue

equals, getSize, getType, hashCode, isReference, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

create

public static ReplacingBasicValue create(org.objectweb.asm.Type type,
                         org.apache.drill.exec.compile.bytecode.ValueHolderIden iden,
                         int index,
                         List<ReplacingBasicValue> valueList)

Create a new value representing a holder (boxed value).

Parameters:

type - the type of the holder

iden - the ValueHolderIden for the holder

index - the original local variable slot assigned to the value

valueList - TODO

Returns:

dump

public void dump(StringBuilder sb,
        int indentLevel)

Dump the value's members to a StringBuilder.

For logging and/or debugging.

Parameters:

sb - the StringBuilder

indentLevel - the amount of indentation (in spaces) to prepend to each line

isReplaceable

public boolean isReplaceable()

Indicates whether or not this value is replaceable.

Returns:

whether or not the value is replaceable

setFrameSlot

public void setFrameSlot(int frameSlot)

associate

public void associate(ReplacingBasicValue other)

Associate this value with another.

This value and/or the other may each already have their own set of associates.

Once associated, these values will share flag values, and a change to any one of them will be shared with all other members of the association.

Parameters:

other - the other value

markFunctionReturn

public void markFunctionReturn()

Mark this value as being used as a function return value.

disableFunctionReturn

public void disableFunctionReturn()

Clear the indication that this value is used as a function return value.

isFunctionReturn

public boolean isFunctionReturn()

Indicates whether or not this value is used as a function return value.

Returns:

whether or not this value is used as a function return value

setFunctionArgument

public void setFunctionArgument()

Mark this value as being used as a function argument.

isFunctionArgument

public boolean isFunctionArgument()

Indicates whether or not this value is used as a function argument.

Returns:

whether or not this value is used as a function argument

setAssignedToMember

public void setAssignedToMember()

Mark this value as being assigned to a class member variable.

isAssignedToMember

public boolean isAssignedToMember()

Indicates whether or not this value is assigned to a class member variable.

Returns:

whether or not this value is assigned to a class member variable

getIden

public org.apache.drill.exec.compile.bytecode.ValueHolderIden getIden()

Return the ValueHolder identity for this value.

Returns:

the ValueHolderIden for this value

getIndex

public int getIndex()

Get the original local variable slot assigned to this value/holder.

Returns:

the original local variable slot assigned to this value/holder

setThis

public void setThis()

Mark this value as a "this" reference.

isThis

public boolean isThis()

Indicates whether or not this value is a "this" reference.

Returns:

whether or not this value is a "this" reference