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device: 0.841
ppc: 0.814
register: 0.813
socket: 0.672
permissions: 0.667
graphic: 0.665
vnc: 0.650
hypervisor: 0.644
kernel: 0.641
performance: 0.638
architecture: 0.630
network: 0.620
semantic: 0.613
assembly: 0.550
boot: 0.545
risc-v: 0.518
peripherals: 0.494
mistranslation: 0.480
PID: 0.474
files: 0.448
arm: 0.443
debug: 0.369
user-level: 0.317
VMM: 0.300
x86: 0.274
i386: 0.240
TCG: 0.232
KVM: 0.048
virtual: 0.026
SH4: ADDV instruction not emulated properly
Description of problem:
ADDV opcode is emulated incorrectly.
The documentation says:
`ADDV Rm, Rn Rn + Rm -> Rn, overflow -> T`
What Qemu actually emulates:
`ADDV Rm, Rn Rn + Rm -> Rm, overflow -> T`
Steps to reproduce:
```c
#include <stdio.h>
int main(void)
{
register unsigned int a asm("r8") = 0x7fffffff;
register unsigned int b asm("r9") = 1;
register unsigned int c asm("r10");
asm volatile("clrt\n"
"addv %2,%0\n"
"movt %1\n"
: "+r"(a), "=r"(c) : "r"(b) :);
printf("Values: a=0x%x b=0x%x c=0x%x\n", a, b, c);
return 0;
}
```
Additional information:
Tested on real hardware (SEGA Dreamcast, GCC 15.0), the program above prints:
`Values: a=0x80000000 b=0x1 c=0x1`
Running with Qemu (and GCC 13.0), the same program prints:
`Values: a=0x7fffffff b=0x80000000 c=0x1`
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