The FPSR quotient byte should be set to the value of the quotient and not the
result. Switch from using floatx80_mod() to floatx80_modrem() which returns
the quotient as a uint64_t which can be used for the quotient byte.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
---
 target/m68k/fpu_helper.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/target/m68k/fpu_helper.c b/target/m68k/fpu_helper.c
index ae839785fa..18594a35af 100644
--- a/target/m68k/fpu_helper.c
+++ b/target/m68k/fpu_helper.c
@@ -523,14 +523,17 @@ static void make_quotient(CPUM68KState *env, int sign, uint32_t quotient)
 
 void HELPER(fmod)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 {
-    res->d = floatx80_mod(val1->d, val0->d, &env->fp_status);
+    uint64_t quotient;
+    int sign = extractFloatx80Sign(val1->d) ^ extractFloatx80Sign(val0->d);
+
+    res->d = floatx80_modrem(val1->d, val0->d, true, &quotient,
+                             &env->fp_status);
 
     if (floatx80_is_any_nan(res->d)) {
         return;
     }
 
-    make_quotient(env, extractFloatx80Sign(res->d),
-                  floatx80_to_int32(res->d, &env->fp_status));
+    make_quotient(env, sign, quotient);
 }
 
 void HELPER(frem)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
-- 
2.30.2

Le 01/01/2023 à 15:43, Mark Cave-Ayland a écrit :
> The FPSR quotient byte should be set to the value of the quotient and not the
> result. Switch from using floatx80_mod() to floatx80_modrem() which returns
> the quotient as a uint64_t which can be used for the quotient byte.
> 
> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
> ---
>   target/m68k/fpu_helper.c | 9 ++++++---
>   1 file changed, 6 insertions(+), 3 deletions(-)
> 

Reviewed-by: Laurent Vivier <laurent@vivier.eu>