HomePhabricator

[libunwind] Add support for PC reg column in arm64

Authored by charco on Feb 17 2021, 1:42 PM.

Description

[libunwind] Add support for PC reg column in arm64

This change adds support for the dwarf PC register column in arm64, allowing
CFI directives to make use of it.

As of the last revision of the DWARF for ARM 64-bit architecture[0], the pc
register has been added as a valir register, with number 32.

This allows libunwinder to restore both pc and lr, which is useful
for stack switches and signal contexts.

[0]:
https://github.com/ARM-software/abi-aa/blob/f52e1ad3f81254497a83578dc102f6aac89e52d0/aadwarf64/aadwarf64.rst

Reviewed By: phosek, #libunwind

Differential Revision: https://reviews.llvm.org/D96901

Details

Committed
charcoFeb 17 2021, 5:42 PM
Reviewer
Restricted Project
Differential Revision
D96901: [libunwind] Add support for PC reg column in arm64
Parents
rG2628e9146120: [NetBSD] Use cortex-a8 as default CPU for ARMv7
Branches
Unknown
Tags
Unknown