Table of Contents

5.4.2.15 Return Statement

Note

This section describes the implementation of MS-VBAL §5.4.2.15 Return Statement.

Syntax

AST node Instruction kind Notes
ReturnStatementNode Return No resolved target.

Return lowers to the InstructionKind Return (RD-VBAL §3.5.2 Instruction).

Runtime Semantics

Return reads the activation's GoSub Resumption List, the per-activation LIFO stack of return offsets that GoSub and a successful On…GoSub branch push onto (RD-VBAL §5.4.2.14 GoSub Statement).

  1. Return pops the GoSub Resumption List.
  2. Execution branches to the popped offset.
Condition Run-time error
The GoSub Resumption List is empty. 3 — Return without GoSub

Nested GoSubs unwind in LIFO order: the innermost Return is taken first.

Return's runtime semantics resolve no target label at execution time: the offset it branches to is the one the matching GoSub pushed.

The GoSub Resumption List is a plain stack because Return depends only on the order of its entries, not on which GoSub pushed each one.

Implementation

  • RDCore.Runtime.Execution.ProcedureExecutor dispatches Return instructions.
  • Return pops the list through CallStackFrame.TryPopGoSubReturn (RD-VBAL §3.5.4 Execution).

⏮️ RD-VBAL §5.4.2.14 GoSub Statement | ⏭️ RD-VBAL §5.4.2.16 On...GoSub Statement

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