avail/avail.compiler.instruction/AvailPushLocalVariable

AvailPushLocalVariable

class AvailPushLocalVariable(var relevantTokens: A_Tuple, variableIndex: Int) : AvailPushVariable

Push either a local variable (the variable itself), a local constant, or an argument.

Author

Mark van Gulik

Parameters

relevantTokens

The A_Tuple of A_Tokens that are associated with this instruction.

variableIndex

The index that the local variable will occupy at runtime within a continuation.

Constructors

AvailPushLocalVariable

fun AvailPushLocalVariable(relevantTokens: A_Tuple, variableIndex: Int)

Construct a new AvailPushLocalVariable.

Functions

fixUsageFlags

open override fun fixUsageFlags( localData: MutableList<AvailVariableAccessNote?>, outerData: MutableList<AvailVariableAccessNote?>, codeGenerator: AvailCodeGenerator)

The instructions of a block are being iterated over. Coordinate optimizations between instructions using localData and outerData, two lists manipulated by overrides of this method. Treat each instruction as though it is the last one in the block, and save enough information in the lists to be able to undo consequences of this assumption when a later instruction shows it to be unwarranted.

writeLineNumberDeltasOn

open fun writeLineNumberDeltasOn(encodedLineNumberDeltas: MutableList<Int>, currentLineNumber: Int): Int

Write an entry to the encoded line number deltas for each L1 instruction generated. Most AvailInstructions write a single L1 instruction, so that implementation is here.

writeNybblesOn

open override fun writeNybblesOn(aStream: NybbleOutputStream)

Write nybbles representing this instruction to the NybbleOutputStream.

Properties

index

val index: Int

A generic index to be interpreted by subclasses. Must be non-negative.

isLastAccess

var isLastAccess: Boolean = false

true iff this instruction is the last use of its variable.

isOuterUse

open val isOuterUse: Boolean

true iff this instruction is a use of an outer variable.

lineNumber

val lineNumber: Int

Answer which line number to say that this instruction occurs on. Use the relevantTokens as an approximation, but subclasses might be able to be more precise. Answer -1 if this instruction doesn't seem to have a location in the source associated with it.

relevantTokens

var relevantTokens: A_Tuple

The tuple of tokens that contributed to producing this instruction.