Core: use QElapsedTimer also in aclintmtimer

Author: jdupak

src/machine/memory/backend/aclintmtimer.cpp

@@ -21,7 +21,7 @@ AclintMtimer::AclintMtimer(Endian simulated_machine_endian)
         value = 0;
     }
 
-    mtime_start_offset = QTime::currentTime();
+    clock.start();
     qt_timer_id = -1;
 }
 
@@ -31,9 +31,7 @@ AclintMtimer::~AclintMtimer() {
 }
 
 uint64_t AclintMtimer::mtime_fetch_current() const {
-    QTime current_time = QTime::currentTime();
-
-    mtime_last_current_fetch = mtime_start_offset.msecsTo(current_time) * (uint64_t)10000;
+    mtime_last_current_fetch = clock.elapsed() * (uint64_t)10000;
 
     return mtime_last_current_fetch;
 }

src/machine/memory/backend/aclintmtimer.h

@@ -6,6 +6,7 @@
 
 #include <QTime>
 #include <cstdint>
+#include <qelapsedtimer.h>
 
 namespace machine { namespace aclint {
 
@@ -63,8 +64,8 @@ namespace machine { namespace aclint {
         unsigned mtimecmp_count;
         uint64_t mtimecmp_value[ACLINT_MTIMECMP_COUNT_MAX] {};
 
+        QElapsedTimer clock;
         const uint8_t mtimer_irq_level;
-        QTime mtime_start_offset;
         uint64_t mtime_user_offset = 0;
         mutable uint64_t mtime_last_current_fetch = 0;
         mutable bool mtimer_irq_active = false;