linux-user/sparc64: Fix the handling of window spill trap

Fix the handling of window spill traps by keeping cansave into account
when calculating the new CWP.

Signed-off-by: Giuseppe Musacchio <[email protected]>
Signed-off-by: Laurent Vivier <[email protected]>
Reviewed-by: Richard Henderson <[email protected]>
Message-Id: <[email protected]>

Author: LemonBoy

bsd-user/main.c

@@ -413,7 +413,11 @@ static void save_window(CPUSPARCState *env)
     save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2));
     env->wim = new_wim;
 #else
-    save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2));
+    /*
+     * cansave is zero if the spill trap handler is triggered by `save` and
+     * nonzero if triggered by a `flushw`
+     */
+    save_window_offset(env, cpu_cwp_dec(env, env->cwp - env->cansave - 2));
     env->cansave++;
     env->canrestore--;
 #endif

linux-user/sparc/cpu_loop.c

@@ -69,7 +69,11 @@ static void save_window(CPUSPARCState *env)
     save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2));
     env->wim = new_wim;
 #else
-    save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2));
+    /*
+     * cansave is zero if the spill trap handler is triggered by `save` and
+     * nonzero if triggered by a `flushw`
+     */
+    save_window_offset(env, cpu_cwp_dec(env, env->cwp - env->cansave - 2));
     env->cansave++;
     env->canrestore--;
 #endif