replace multiple instructions with macro SAVE_CONTEXT and RESTORE_CONTEXT

board/QEMU_Spike/Src/main.c

@@ -0,0 +1,62 @@
+/*
+ * main.c
+ *
+ *  Created on: Sep 13, 2019
+ *      Author: ace
+ */
+
+#include "tos.h"
+
+#define TASK_SIZE 512
+k_task_t k_task_task1;
+k_task_t k_task_task2;
+uint8_t k_task1_stk[TASK_SIZE];
+uint8_t k_task2_stk[TASK_SIZE];
+
+int share = 123;
+void task1(void *pdata)
+{
+	int t1 = 0;
+	while(1)
+	{
+		t1++;
+		share++;
+		//k_tick_t delay = tos_millisec2tick(10);
+		//tos_task_delay(delay);
+		tos_task_yield();
+		//osDelay(10);
+		//asm("wfi;");
+	}
+}
+
+void task2(void *pdata)
+{
+	int t2 = 0;
+	while(1)
+	{
+		t2--;
+		share--;
+		//tos_task_delay(10);
+		tos_task_yield();
+		asm("wfi;");
+	}
+}
+
+int main(void)
+{
+	tos_knl_init();
+
+	tos_task_create(&k_task_task1, "task1", task1, NULL, 3, k_task1_stk, TASK_SIZE, 0);
+	tos_task_create(&k_task_task2, "task2", task2, NULL, 3, k_task2_stk, TASK_SIZE, 0);
+
+	tos_knl_start();
+
+
+	int c = 0;
+	while(1)
+	{
+		c++;
+		asm("wfi;");
+	}
+
+}