STM32 HAL 内存溢出中断服务函数

在 STM32 HAL 中，如果发生了内存溢出，会触发硬件中断，此时应该执行内存溢出中断服务函数来处理这个问题。

内存溢出中断服务函数的代码示例如下：

void HardFault_Handler(void)
{
  __ASM volatile("TST LR, #4");
  __ASM volatile("ITE EQ");
  __ASM volatile("MRSEQ R0, MSP");
  __ASM volatile("MRSNE R0, PSP");
  __ASM volatile("B hard_fault_handler_c");
}

void hard_fault_handler_c(unsigned int * hardfault_args)
{
  volatile unsigned int stacked_r0;
  volatile unsigned int stacked_r1;
  volatile unsigned int stacked_r2;
  volatile unsigned int stacked_r3;
  volatile unsigned int stacked_r12;
  volatile unsigned int stacked_lr;
  volatile unsigned int stacked_pc;
  volatile unsigned int stacked_psr;

  stacked_r0 = ((unsigned long) hardfault_args[0]);
  stacked_r1 = ((unsigned long) hardfault_args[1]);
  stacked_r2 = ((unsigned long) hardfault_args[2]);
  stacked_r3 = ((unsigned long) hardfault_args[3]);
  stacked_r12 = ((unsigned long) hardfault_args[4]);
  stacked_lr = ((unsigned long) hardfault_args[5]);
  stacked_pc = ((unsigned long) hardfault_args[6]);
  stacked_psr = ((unsigned long) hardfault_args[7]);

  printf("[HardFault]\n");
  printf("R0 = %x\n", stacked_r0);
  printf("R1 = %x\n", stacked_r1);
  printf("R2 = %x\n", stacked_r2);
  printf("R3 = %x\n", stacked_r3);
  printf("R12 = %x\n", stacked_r12);
  printf("LR = %x\n", stacked_lr);
  printf("PC = %x\n", stacked_pc);
  printf("PSR = %x\n", stacked_psr);

  while (1);
}

在该代码中，`HardFault_Handler` 函数是内存溢出中断服务函数的入口函数。在该函数中，首先使用汇编代码判断当前使用的堆栈是主堆栈还是进程堆栈，然后再跳转到 `hard_fault_handler_c` 函数中执行实际的处理。

在 `hard_fault_handler_c` 函数中，首先将异常发生时的相关寄存器的值保存到变量中，然后输出相关信息，并在最后进入死循环，以防止程序继续执行。