Some intrinsics allow control over areas of memory, so you can manipulate memory blocks.
void *__alloca(ulong);
__alloca implements alloca() in the compiler. char *__strcpy(char *, const char *);
__strcpy() detects copies of constant size and calls __memcpy() . This intrinsic requires that a __strcpy function be implemented because if the string is not a constant it will call __strcpy to do the copy.
void *__memcpy(void *, const void *, size_t);
__memcpy() provides access to the block move in the code generator to do the block move inline.