Use flag rather than instruction count to handle step mode.

src/core/arm/unicorn/arm_unicorn.cpp

@@ -237,7 +237,7 @@ void ARM_Unicorn::ExecuteInstructions(int num_instructions) {
         //}
         Kernel::Thread* thread = Kernel::GetCurrentThread();
         SaveContext(thread->context);
-        if (last_bkpt_hit || (num_instructions == 1)) {
+        if (last_bkpt_hit || GDBStub::GetCpuStepFlag()) {
             last_bkpt_hit = false;
             GDBStub::Break();
             GDBStub::SendTrap(thread, 5);

src/core/core.cpp

@@ -63,7 +63,6 @@ System::ResultStatus System::RunLoop(bool tight_loop) {
         // execute. Otherwise, get out of the loop function.
         if (GDBStub::GetCpuHaltFlag()) {
             if (GDBStub::GetCpuStepFlag()) {
-                GDBStub::SetCpuStepFlag(false);
                 tight_loop = false;
             } else {
                 return ResultStatus::Success;
@@ -81,6 +80,7 @@ System::ResultStatus System::RunLoop(bool tight_loop) {
 
     if(GDBStub::IsServerEnabled())
     {
+        GDBStub::SetCpuStepFlag(false);
         GDBStub::SetInstCacheValidity(true);
     }