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Intel BLSI CF computation bug
Description of problem:
CF flag computation of BLSI instruction is wrong. It seems #1370 was not completely fixed.
Steps to reproduce:
1. Compile `example.c` using this command: `gcc -o example.bin example.c`. My gcc version is 12.3.0, but other versions may work.
```
int main() {
__asm__ (
"movq $0x1, %r8\n"
"mov $0xedbf530a, %r9\n"
"push $0x1\n"
"popf\n"
"blsi %r9d, %r8d\n"
"pushf\n"
"pop %rax\n"
"pop %rbp\n"
"ret\n"
);
return 0;
}
```
2. Run `./example.bin`. Then check the return code using `echo $?`. It should be 3.
```
$ ./example.bin
$ echo $?
3
```
3. Run `./qemu-x86_64 ./example.bin`. Then check the return code using `echo $?`. It should be 2.
```
$ ./qemu-x86_64 ./example.bin
$ echo $?
2
```
The return code of `./example.bin` contains the value of the `RFLAGS` register after executing the `BLSI` instruction.
Additional information:
|