[PATCH v2 4/6] target/openrisc: Use cpu_unwind_state_data for mfspr

[Richard Henderson <richard.henderson@linaro.org>]

Since we do not plan to exit, use cpu_unwind_state_data
and extract exactly the data requested.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/openrisc/sys_helper.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/target/openrisc/sys_helper.c b/target/openrisc/sys_helper.c
index a3508e421d..dde2fa1623 100644
--- a/target/openrisc/sys_helper.c
+++ b/target/openrisc/sys_helper.c
@@ -199,6 +199,7 @@ target_ulong HELPER(mfspr)(CPUOpenRISCState *env, target_ulong rd,
                            target_ulong spr)
 {
 #ifndef CONFIG_USER_ONLY
+    uint64_t data[TARGET_INSN_START_WORDS];
     MachineState *ms = MACHINE(qdev_get_machine());
     OpenRISCCPU *cpu = env_archcpu(env);
     CPUState *cs = env_cpu(env);
@@ -232,14 +233,20 @@ target_ulong HELPER(mfspr)(CPUOpenRISCState *env, target_ulong rd,
         return env->evbar;
 
     case TO_SPR(0, 16): /* NPC (equals PC) */
-        cpu_restore_state(cs, GETPC(), false);
+        if (cpu_unwind_state_data(cs, GETPC(), data)) {
+            return data[0];
+        }
         return env->pc;
 
     case TO_SPR(0, 17): /* SR */
         return cpu_get_sr(env);
 
     case TO_SPR(0, 18): /* PPC */
-        cpu_restore_state(cs, GETPC(), false);
+        if (cpu_unwind_state_data(cs, GETPC(), data)) {
+            if (data[1] & 2) {
+                return data[0] - 4;
+            }
+        }
         return env->ppc;
 
     case TO_SPR(0, 32): /* EPCR */
-- 
2.34.1