Xtensa GPR and ABI
来自Jack's Lab
目录 |
1 Overview
Two different ABI:
- Windowed register ABI, works with the Windowed Register Option (ESP32 use this ABI by default)
- CALL0 ABI, used with any Xtensa processor (worse performance)
Instruction CALL0 is for the CALL0 ABI
Instruction CALL4/CALL8/CALL12 is for the windowed register ABI
2 Windowed Register ABI
2.1 Argument passing
2.2 Return value
3 CALL0 ABI
3.1 Argument passing
3.2 Return value
