semihosting: Return void from do_common_semihosting

Perform the cleanup in the FIXME comment in common_semi_gdb_syscall.
Do not modify guest registers until the syscall is complete,
which in the gdbstub case is asynchronous.

In the synchronous non-gdbstub case, use common_semi_set_ret
to set the result.  Merge set_swi_errno into common_semi_cb.
Rely on the latter for combined return value / errno setting.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
index 4a6700c890..be28615e23 100644
--- a/target/riscv/cpu_helper.c
+++ b/target/riscv/cpu_helper.c
@@ -1347,7 +1347,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
 
     if  (cause == RISCV_EXCP_SEMIHOST) {
         if (env->priv >= PRV_S) {
-            env->gpr[xA0] = do_common_semihosting(cs);
+            do_common_semihosting(cs);
             env->pc += 4;
             return;
         }