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instruction: 0.827
runtime: 0.117
syscall: 0.056
m68k: fpu: fsave/frestore should be enabled for 68020/68030
Description of problem:
valid 68020/68030 code can use `fsave`/`frestore` instructions to save/restore the state of an external 68881/68882 but currently QEMU only allows these instructions on 68040 and everyone else gets an f-line exception.
I guess something like this to allow frestore/fsave. m68k programmers reference manual says they are 68881/68882/68040 and there don's seem to be any differences.
``` diff
diff --git a/target/m68k/translate.c b/target/m68k/translate.c
index d5d2322329..92dc9d8563 100644
--- a/target/m68k/translate.c
+++ b/target/m68k/translate.c
@@ -5455,7 +5455,7 @@ DISAS_INSN(frestore)
gen_exception(s, s->base.pc_next, EXCP_PRIVILEGE);
return;
}
- if (m68k_feature(s->env, M68K_FEATURE_M68040)) {
+ if (m68k_feature(s->env, M68K_FEATURE_FPU)) {
SRC_EA(env, addr, OS_LONG, 0, NULL);
/* FIXME: check the state frame */
} else {
@@ -5472,7 +5472,7 @@ DISAS_INSN(fsave)
return;
}
- if (m68k_feature(s->env, M68K_FEATURE_M68040)) {
+ if (m68k_feature(s->env, M68K_FEATURE_FPU)) {
/* always write IDLE */
TCGv idle = tcg_constant_i32(0x41000000);
DEST_EA(env, insn, OS_LONG, idle, NULL);
```
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