For the Power Architecture
® architecture, the Linux kernel uses the following registers:
- stack pointer
- pointer to task_struct for the current task
- parameter passing and return values
- parameter passing
- small data area pointer
- GOT pointer
- frame pointer
A function can use
without saving and restoring them.
have to be preserved
so they must be saved and restored when you want to use them.
must be preserved,
can be used without saving & restoring them.
[ Posted Tue, 15 Jul 2003 by Paul Mackerras to email@example.com
See also the (E)ABI specifications for the Power Architecture
Developing PowerPC Embedded Application Binary Interface (EABI) Compliant Programs