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arch.x86.fault.idoe

Into Detected Overflow Exception handler (CPU vector 4).

Overview

Handles the x86 Overflow exception (#OF, vector 4), which is raised when the INTO instruction is executed and the overflow flag (OF) is set. The handler disables interrupts and triggers a kernel panic.

Dependencies

  • arch.x86.util
  • arch.x86.panic
  • arch.x86.isr.types
  • arch.x86.isr.mgr
  • arch.x86.idt

Functions and Procedures

register

procedure register();

Registers the overflow handler with arch.x86.isr.mgr at ISR vector 4. Must be called during fault subsystem initialisation.

Notes

  • The handler calls correctInterruptRegisters(false) because vector 4 does not push an error code.
  • After adjusting register pointers, x86_panic is called with fault identifier 'arch.x86.fault.idoe' and description 'Into Detected Overflow Exception.'.
  • The INTO instruction is rarely used in modern code; this exception is primarily a legacy compatibility handler.