Class AssignExpressionToSymbol

java.lang.Object

org.ek9lang.compiler.phase7.generator.AbstractGenerator

org.ek9lang.compiler.phase7.generator.AssignExpressionToSymbol

All Implemented Interfaces:

BiFunction<ISymbol, EK9Parser.AssignmentExpressionContext, List<IRInstr>>

final class AssignExpressionToSymbol
extends AbstractGenerator
implements BiFunction<ISymbol, EK9Parser.AssignmentExpressionContext, List<IRInstr>>

Field Summary

Fields inherited from class AbstractGenerator

constantCopyOnAccessLoader, debugInfoCreator, instructionBuilder, MAX_MESSAGE_LENGTH, stackContext, synthesisedCallMetaData, typeNameOrException

Constructor Summary

Constructors

Constructor	Description
AssignExpressionToSymbol(IRGenerationContext stackContext, VariableMemoryManagement variableMemoryManagement, ScopeRegisterOnly scopeRegisterOnly, PromotionCallGenerator promotionCallGenerator, boolean release, Function<String, List<IRInstr>> assignmentGenerator)

Method Summary

Modifier and Type	Method	Description
List<IRInstr>	apply(ISymbol lhsSymbol, EK9Parser.AssignmentExpressionContext ctx)
(package private) static boolean	isEscapingResultExpression(EK9Parser.AssignmentExpressionContext ctx)	True when the RHS hands back a temp that ALREADY carries a producer +1 (so this consumer must SCOPE_REGISTER only, never a second RETAIN — a second RETAIN leaves two RETAINs against one SCOPE_REGISTER = a +1 ARC leak on the LLVM backend).

Methods inherited from class AbstractGenerator

addCoverageProbe, createTempVariable, createTempVariableFromContext, extractReturnType, getRecordedSymbolOrException, processBlockStatements, processBlockStatements, truncateMessage, truncateMessage

Methods inherited from class Object

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

Methods inherited from interface BiFunction

andThen

Constructor Details

AssignExpressionToSymbol

AssignExpressionToSymbol(IRGenerationContext stackContext,
 VariableMemoryManagement variableMemoryManagement,
 ScopeRegisterOnly scopeRegisterOnly,
 PromotionCallGenerator promotionCallGenerator,
 boolean release,
 Function<String, List<IRInstr>> assignmentGenerator)

Method Details

apply

public List<IRInstr> apply(ISymbol lhsSymbol,
 EK9Parser.AssignmentExpressionContext ctx)

Specified by:

apply in interface BiFunction<ISymbol, EK9Parser.AssignmentExpressionContext, List<IRInstr>>

isEscapingResultExpression

static boolean isEscapingResultExpression(EK9Parser.AssignmentExpressionContext ctx)

True when the RHS hands back a temp that ALREADY carries a producer +1 (so this consumer must SCOPE_REGISTER only, never a second RETAIN — a second RETAIN leaves two RETAINs against one SCOPE_REGISTER = a +1 ARC leak on the LLVM backend). Two families qualify:

• the control-flow expression forms (switch/while/for/try) that AssignmentExprInstrGenerator.processControlFlowExpression STOREs+RETAINs; and
• the coalescing (?? ?: <? >? <=? >=?) and ternary (control<-then:else) expressions, which lower to a CONTROL_FLOW_CHAIN whose body-results are RETAIN'd to escape the chain's inner scope (see ControlFlowChainGenerator.produceEscapingResult and generateTernary). Detected on ctx.expression() exactly as ExprInstrGenerator routes them.

THE predicate for this choice: a try-with-resources resource initialiser asks it too (TryCatchStatementGenerator), so the two consumers of an assignmentExpression cannot disagree about which forms hand back a +1.