# C++ exception handling

The exception handling model for the Hexagon processor is based on
the DWARF2 stack unwinding mechanism.

Registers R0 to R3 are reserved to communicate between exception
handling library routines and exception handlers.

The stack location for saved LR (see [Software stack](https://docs.qualcomm.com/doc/80-N3040-23/topic/abi-software-stack.html#software-stack))
is used to store the address of an exception handler to which the
procedure returns.

Last Published: Oct 06, 2026

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