在下面的代码中,我不知道为什么我从不输入if。对我来说,这是有道理的,它进入了如果:

void Mem_Coalesce(){


    list_t* temp;
    temp = freep;
        if(free_node_count == 2){
        //will finish
             printf("Addr of temp is  %llx\n\n", (long long unsigned) temp);
                 printf("Size of Temp is  %d\n\n", temp->size);
             printf("Addr of end of temp free node space is  %llx\n\n", (long long unsigned) ((char*)temp + temp->size));
             printf("Addr of start temp->next  is  %llx\n\n", (long long unsigned) temp->next);
        if( ((char*)temp + (temp->size)) == (char*)(temp->next)){
                printf("Entered the if statement\n");
                        temp->size += (temp->next)->size;
                temp->next = NULL;
        }


    }else {

        while(temp->next != NULL  ){

            if( ((char*)temp + (temp->size)) == (char*)(temp->next)){

                temp->size += (temp->next)->size;
                                printf("coalesced size is %d temp->size \n", temp->size);
                temp->next = (temp->next)->next;
                ((temp->next)->next)->prev = temp;
            }
            temp=temp->next;

        }

    }



}

结果是
Addr of temp is  7f9c1e89b070

Size of Temp is  200

Addr of end of temp free node space is  7f9c1e89b138

Addr of start temp->next  is  7f9c1e89b278

正如你所见,它从未进入if statement。另外,让我知道是否有其他算法可以更有效地进行内存合并。

最佳答案

您在此处以十进制打印temp->size

printf("Size of Temp is  %d\n\n", temp->size);
                         ^^

打印十六进制指针值时:
printf("Addr of temp is  %llx\n\n", (long long unsigned) temp);
                         ^^^^

十进制是十六进制的200C8+0xC8=0x70。因此,当您将0x138添加到0xC8时,结果是0x7f9c1e89b070,它不等于0x7f9c1e89b138,因此您不输入if语句。

07-26 04:07