semantic: 0.995 graphic: 0.860 device: 0.736 vnc: 0.420 boot: 0.411 debug: 0.352 permissions: 0.340 socket: 0.263 network: 0.171 other: 0.159 PID: 0.153 performance: 0.140 files: 0.125 KVM: 0.083 x86 BEXTR semantic bug Description of problem: The result of instruction BEXTR is different with from the CPU. The value of destination register is different. I think QEMU does not consider the operand size limit. Steps to reproduce: 1. Compile this code ``` void main() { asm("mov rax, 0x17b3693f77fb6e9"); asm("mov rbx, 0x8f635a775ad3b9b4"); asm("mov rcx, 0xb717b75da9983018"); asm("bextr eax, ebx, ecx"); } ``` 2. Execute and compare the result with the CPU. - CPU - RAX = 0x5a - QEMU - RAX = 0x635a775a Additional information: This bug is discovered by research conducted by KAIST SoftSec.