2022.08.25
Flags in Gem5
X86 Jump Condition (Jcc)
amd64.pdf: General-Purpose Instruction Reference: Jcc
vim-markdown TableFormat does not handle \| well,
use v to represent logic operation OR.
| Cond | F | Cond | !F |
|---|---|---|---|
| O | O | NO | !O |
| B,C,NAE | C | NB,NC,AE | !C |
| Z,E | Z | NZ,NE | !Z |
| BE,NA | CvZ | NBE,A | !C&!Z |
| S | S | NS | !S |
| P,PE | P | NP,PO | !P |
| L,NGE | S!=O | NL,GE | S==O |
| LE,NG | Zv(S!=O) | NLE,G | !Z&(S==O) |
A64 Jump Condtion (B.cond)
2021.armv8.pdf: C6.2.25 B.cond => J1.3.3 shared/functions/system/ConditionHolds:
v: or
| Cond | F | Cond | !F |
|---|---|---|---|
| EQ | Z | NE | !Z |
| CS | C | CC | !C |
| MI | N | PL | !N |
| VS | V | VC | !V |
| HI | C&!Z | LS | !CvZ |
| GE | N==V | LT | N!=V |
| GT | (N==V)&!Z | LE | (N!=V)vZ |
| AL | True |
mapping
N?OF=(SF!=OF)?OF 0=0?0=(0!=0)?0 0=1?1=(0!=1)?1 1=1?0=(1!=0)?0 1=0?1=(1!=1)?1 Therefor, ? is !=
OF:V CF:C ZF:Z SF:N!=V PF
Z:ZF C:CF N:SF!=OF V:OF