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instruction: 0.744
runtime: 0.148
syscall: 0.108
x86 ADOX and ADCX semantic bug
Description of problem:
The result of instruction ADOX and ADCX are different from the CPU. The value of one of EFLAGS is different.
Steps to reproduce:
1. Compile this code
```
void main() {
asm("push 512; popfq;");
asm("mov rax, 0xffffffff84fdbf24");
asm("mov rbx, 0xb197d26043bec15d");
asm("adox eax, ebx");
}
```
2. Execute and compare the result with the CPU. This problem happens with ADCX, too (with CF).
- CPU
- OF = 0
- QEMU
- OF = 1
Additional information:
This bug is discovered by research conducted by KAIST SoftSec.
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