enum { CacheLineSize = 64 }; // StripedMap<T> 是一个模板类,根据传递的实际参数决定其中 array 成员存储的元素类型 // 能通过对象的地址,运算出 Hash 值,通过该 hash 值找到对应的 value template<typename T> class StripedMap { #if TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR enum { StripeCount =...
The implementation also has a neat trick. In cases where the size of the original buffer is big enough, the trailing bytes of the buffer can be set with a single (possibly unaligned) store operation. The end address of the buffer is computed, and 8 (or 16) bytes is subtracted from it...
blk_mq_init_sq_queueHelper for setting up a queue with mq ops, given queue depth, and* the passed in mq ops flags. blkdev_getgeo check_partition find_label scsi_cmd_ioctl scsi_req_initscsi_req_init - initialize certain fields of a scsi_request structure*@req: Pointer to a scsi_reques...
A structure Data with an integer, a float, and a character array is defined and initialized. memset() sets all bytes in the structure to -1, filling the fields with default values. The structure fields are printed to show that memset() has affected all fields in the structure....
I also sometimes see that the data copied is incorrect. For instance, a variable will have an invalid number, like the bytes copied were maybe shifted? Here is a better description of my structs. I have an array[5000] of largeStruct. sizeof(largeStruct) = 32384 ...
memset() can be used at any time and for any kind of memory structure, including single variables, arrays, and objects. The limitation is that it can't properly set each element in an array to any value, because it doesn't have the concept of element. It initializesmemory, not arrays...
The entire structure appears to be a baseclass with virtual functions, which can be implemented differently for various purposes in a derived class. However, this is unrelated to the usage ofmemset. Solution 2: While memset can be used in C++, if you prefer the conventional C++ approach to ...
the decide-and-deposit step a few times, whereas memset() needs to clear the entire thing." If the array is *that* sparse, it's probably the wrong data structure: Stick the data on a linked list, for example, and memset() will be entirely unnecessary. If the size of the memory blo...
Thisarticleis about getters and setters and whether you need to write them all. If you have a structure with several fields, it can perform 30% faster than the version with getters. This is because of the copy operation made by the getter. Switching to returning a value by reference inste...
method allocates a region of memory with 200 chars as you explicitly code the amount of memory you want, //use free() to destroy the memory allocated after use. free(str->name); //first destroy the memory, for the variable inside the structure free(str); //destroy the memory allocated...