Landing: cfe20dd118f5
Project / Subsystem
gcc / xtensa
Date
2026-09-12
Author
Takayuki 'January June' Suwa
Commit
cfe20dd118f5b83cb5dfac890e02b5b0a169abc1
Source
github
Perf win
No
Breaking
No
All attributes
- project
- gcc
- subsystem
- xtensa
- patch_id
- —
- commit_hash
- cfe20dd118f5b83cb5dfac890e02b5b0a169abc1
- source_type
- github
- headline
- XTENSA: Exclude A0 from RL_REGS when Windowed ABI is active
- tldr
- Xtensa target excludes A0 register from preferred reload set when using Windowed ABI.
- author
- Takayuki 'January June' Suwa
- outcome
- committed
- performance_win
- false
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • xtensa
- • register allocation
- • ABI
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-09-12T00:00:00.000Z
On Xtensa targets using the Windowed Register ABI, the A0 register is reserved for return addresses and cannot be used for general purposes. This commit modifies the xtensa_conditional_register_usage function to exclude the A0 register from the RL_REGS register class, which represents preferred reload registers. This ensures that the compiler does not attempt to use A0 for reloads, preventing potential conflicts with its dedicated role for return addresses.