target-alpha: Implement call_pal without an exception

The destination of the call_pal, and the cpu state, is very predictable;
there's no need for exiting the cpu loop.

Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 12 insertions, 0 deletions

diff --git a/target-alpha/sys_helper.c b/target-alpha/sys_helper.c
index bd94597d36..ce51ed6002 100644
--- a/target-alpha/sys_helper.c
+++ b/target-alpha/sys_helper.c
@@ -51,6 +51,17 @@ void helper_hw_ret(CPUAlphaState *env, uint64_t a)
     }
 }
 
+void helper_call_pal(CPUAlphaState *env, uint64_t pc, uint64_t entry_ofs)
+{
+    int pal_mode = env->pal_mode;
+    env->exc_addr = pc | pal_mode;
+    env->pc = env->palbr + entry_ofs;
+    if (!pal_mode) {
+        env->pal_mode = 1;
+        swap_shadow_regs(env);
+    }
+}
+
 void helper_tbia(CPUAlphaState *env)
 {
     tlb_flush(env, 1);
@@ -91,4 +102,5 @@ void helper_set_alarm(CPUAlphaState *env, uint64_t expire)
         qemu_del_timer(cpu->alarm_timer);
     }
 }
+
 #endif /* CONFIG_USER_ONLY */