Package serp.bytecode
Class StackInstruction
java.lang.Object
serp.bytecode.CodeEntry
serp.bytecode.Instruction
serp.bytecode.TypedInstruction
serp.bytecode.StackInstruction
- All Implemented Interfaces:
BCEntity
,VisitAcceptor
Represents an instruction that manipulates the stack of the current
frame. Using the
setType(java.lang.String)
methods is a hint about the type being
manipulated that might cause this instruction to use the wide version
of the opcode it represents (if manipulating a long or double). This
saves the developer from having to decide at compile time whether to
use pop
or pop2
, etc.-
Field Summary
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Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionvoid
acceptVisit
(BCVisitor visit) Accept a visit from aBCVisitor
, calling the appropriate methods to notify the visitor that it has entered this entity, and to provide it with the proper callbacks for each sub-entity owned by this one.int
Return the number of stack positions this instruction pushes or pops during its execution.This method will always return null; useisWide()
to determine if this is pop2, dup2, etc.boolean
isWide()
Return whether to use the wide form of the current opcode for operations on longs or doubles.Set the type of this instruction.setWide
(boolean wide) Set whether to use the wide form of the current opcode for operations on longs or doubles.Methods inherited from class serp.bytecode.TypedInstruction
getType, getTypeBC, mapType, setType, setType
Methods inherited from class serp.bytecode.Instruction
equalsInstruction, getByteIndex, getClassLoader, getCode, getLength, getLineNumber, getLogicalStackChange, getName, getOpcode, getPool, getProject, invalidate, invalidateByteIndexes, isValid, read, read, setOpcode, write
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Constructor Details
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StackInstruction
StackInstruction(Code owner, int opcode)
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Method Details
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getStackChange
public int getStackChange()Description copied from class:Instruction
Return the number of stack positions this instruction pushes or pops during its execution.- Overrides:
getStackChange
in classInstruction
- Returns:
- 0 if the stack is not affected by this instruction, a positive number if it pushes onto the stack, and a negative number if it pops from the stack
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getTypeName
This method will always return null; useisWide()
to determine if this is pop2, dup2, etc.- Specified by:
getTypeName
in classTypedInstruction
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setType
Description copied from class:TypedInstruction
Set the type of this instruction. Types that have no direct support will be converted accordingly.- Specified by:
setType
in classTypedInstruction
- Returns:
- this instruction, for method chaining
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isWide
public boolean isWide()Return whether to use the wide form of the current opcode for operations on longs or doubles. -
setWide
Set whether to use the wide form of the current opcode for operations on longs or doubles.- Returns:
- this instruction, for method chaining
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acceptVisit
Description copied from interface:VisitAcceptor
Accept a visit from aBCVisitor
, calling the appropriate methods to notify the visitor that it has entered this entity, and to provide it with the proper callbacks for each sub-entity owned by this one.- Specified by:
acceptVisit
in interfaceVisitAcceptor
- Overrides:
acceptVisit
in classInstruction
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