| |
|
CALLEE |
| REGISTER |
USAGE |
SAVE |
| Integer Registers |
| r01 |
Used in prolog/epilog |
NO |
| r1 |
Stack pointer |
YES |
| r2 |
TOC pointer (reserved) |
YES |
| r3 |
1st para/return val |
NO |
| r4-r10 |
3-8th para |
NO |
| r11 |
Environment pointer |
NO |
| r12 |
Used by global linkage |
NO |
| r13 |
reserved system thread ID |
N/A |
| r14-31 |
Global int registers |
YES |
| Floating Point Registers |
| f0 |
Scratch reg |
NO |
| f1-13 |
1-13th fp para |
NO |
| f14-f31 |
Global fp regs |
YES |
| Special Registers |
| LR |
Link register |
YES |
| CTR |
Count register |
NO |
| XER |
Fixed pt exception |
NO |
| FPSCR |
fp status & ctrl |
NO |
| CR0-CR7 |
Condition reg fields, each 4 bits wide |
2, 3, 4 : YES |
| Vector Registers |
| v0-v1 |
scratch regs |
NO |
| v2-v13 |
vec para regs |
NO |
| v14-v19 |
scratch regs |
NO |
| v20-v31 |
global vregs |
YES |
| vrsave |
(32 bits) |
YES |
.
|
