instruction: 0.901
syscall: 0.049
runtime: 0.049


x86 CVT* series instructions fault
Description of problem:
For example, CVTSD2SS instruction converts SRC[63:0] double precision floating point to DEST[31:0] single precision floating point. Although the CVTSD2SS instruction uses only 8 bytes, if it overlaps page boundary, I think QEMU tries to access over the valid memory and crashes.
Steps to reproduce:
1. Compile this code
```
void main() {
    mmap(0x555555559000, 0x1000, flag, ~~, 0);
    asm("cvtsd2ss xmm1, qword ptr [0x555555559ff8]");
}
```
2. Execute. QEMU crashes but CPU does not.
Additional information:
This bug is discovered by research conducted by KAIST SoftSec.