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+instruction: 0.951
+device: 0.841
+socket: 0.672
+graphic: 0.665
+vnc: 0.650
+network: 0.620
+semantic: 0.613
+assembly: 0.550
+boot: 0.545
+mistranslation: 0.480
+other: 0.332
+KVM: 0.048
+
+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`