org.jruby.ir.instructions

Class ToggleBacktraceInstr

java.lang.Object

org.jruby.ir.instructions.Instr

org.jruby.ir.instructions.NoOperandInstr

org.jruby.ir.instructions.ToggleBacktraceInstr

public class ToggleBacktraceInstr
extends NoOperandInstr

This instruction toggles a single per thread field which specifies whether an exception being thrown needs to generate backtrace info. At any point after toggling this to be false (no backtrace) you may encounter a nested exception which does require a backtrace. This nested exception will toggle back to needing an exception. In theory, we could restore this field as we unwind frames but largely this optimization only occurs in very simple scenarios. Also important to note this is only requesting for a backtrace or not. If you request no backtrace but the error is not a StandardError exception it will still be required to generate a backtrace.

Field Summary

Fields inherited from class org.jruby.ir.instructions.Instr

EMPTY_OPERANDS

Constructor Summary

Constructors

Constructor and Description
ToggleBacktraceInstr(boolean requiresBacktrace)

Method Summary

Methods

Modifier and Type	Method and Description
Instr	clone(CloneInfo info) Clone the instruction for use in an inlining context (either when a scope is inlined into another scope, or when a block has to be cloned because its associated call belongs to an inlined scope).
static ToggleBacktraceInstr	decode(IRReaderDecoder d)
void	encode(IRWriterEncoder e)
boolean	requiresBacktrace()
String[]	toStringNonOperandArgs()
void	visit(IRVisitor visitor)

Methods inherited from class org.jruby.ir.instructions.NoOperandInstr

getOperands, setOperand

Methods inherited from class org.jruby.ir.instructions.Instr

canBeDeletedFromScope, canRaiseException, cloneOperands, computeScopeFlags, dumpableFields, getIPC, getOperation, getRPC, getUsedVariables, hasSideEffects, interpret, interpretAndGetNewIPC, isDead, isDeletable, markDead, renameVars, setIPC, setRPC, simplifyAndGetResult, simplifyOperands, toString, transfersControl

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

ToggleBacktraceInstr

public ToggleBacktraceInstr(boolean requiresBacktrace)

Method Detail

requiresBacktrace

public boolean requiresBacktrace()

toStringNonOperandArgs

public String[] toStringNonOperandArgs()

Overrides:

toStringNonOperandArgs in class Instr

encode

public void encode(IRWriterEncoder e)

Overrides:

encode in class Instr

decode

public static ToggleBacktraceInstr decode(IRReaderDecoder d)

visit

public void visit(IRVisitor visitor)

Overrides:

visit in class Instr

clone

public Instr clone(CloneInfo info)

Description copied from class: Instr

Clone the instruction for use in an inlining context (either when a scope is inlined into another scope, or when a block has to be cloned because its associated call belongs to an inlined scope). This might renaming variables and labels to eliminate naming conflicts. The implementation might vary on the cloning mode.

Specified by:

clone in class Instr

Parameters:

info - This object manages renaming of variables and labels, handles args and return values.

Returns:

a new instruction that can be used in the target scope.