Implement target_cpu_clone_regs to clone the resister state on a fork.

Signed-off-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Kyle Evans <kevans@FreeBSD.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
 bsd-user/arm/target_arch_cpu.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/bsd-user/arm/target_arch_cpu.h b/bsd-user/arm/target_arch_cpu.h
index 66215684d6f..fa45d9335d6 100644
--- a/bsd-user/arm/target_arch_cpu.h
+++ b/bsd-user/arm/target_arch_cpu.h
@@ -36,6 +36,14 @@ static inline void target_cpu_init(CPUARMState *env,
     }
 }
 
+static inline void target_cpu_clone_regs(CPUARMState *env, target_ulong newsp)
+{
+    if (newsp) {
+        env->regs[13] = newsp;
+    }
+    env->regs[0] = 0;
+}
+
 static inline void target_cpu_reset(CPUArchState *cpu)
 {
 }
-- 
2.33.1