템플릿 함수 호출에 대한 gcov 결과를 해석하는 방법

Question

질문 1 : _ZN21CircularBufferManager4readIlEEmPT_m과 같은 함수 이름을 어떻게 해석합니까? 긴 함수 이름 (예 : l, t, h, d)에서 "읽음"후 두 번째 문자가 유형과 관련이 있어야합니다. 서명되지 않은 char, unsigned short, signed long, double을 사용합니다.

질문 2 : 라인 # 227에서 16 가지를 봅니다. 왜 16? 반면에 라인 # 222는 8 개의 분기를 가지며, 이는 2 개의 상태 (true 또는 false)의 4 개의 함수가 8 개의 분기를 만들기 때문에 나에게 의미가 있습니다.

첫 번째 질문에 대한

 -: 216: template<typename Type> 
function _ZN21CircularBufferManager4readIlEEmPT_m called 2 returned 100% blocks executed 63% 
function _ZN21CircularBufferManager4readItEEmPT_m called 2 returned 100% blocks executed 50% 
function _ZN21CircularBufferManager4readIhEEmPT_m called 10 returned 100% blocks executed 94% 
function _ZN21CircularBufferManager4readIdEEmPT_m called 8 returned 100% blocks executed 94% 
     22: 217: uint32 read(Type* data, uint32 element_count) 
     -: 218: { 
     22: 219:  uint32 size(sizeof(Type)*element_count); 
     -: 220: 
     22: 221:  uint32 write_pos_alias(this->write_pos); 
     22: 222:  if (this->read_pos > this->write_pos) { 
branch 0 taken 0% (fallthrough) 
branch 1 taken 100% 
branch 2 taken 0% (fallthrough) 
branch 3 taken 100% 
branch 4 taken 20% (fallthrough) 
branch 5 taken 80% 
branch 6 taken 13% (fallthrough) 
branch 7 taken 88% 
     3: 223:   write_pos_alias += this->allocated_size; 
     -: 224:  } 
     -: 225:  assert(write_pos_alias >= this->read_pos); 
     22: 226:  uint32 n(write_pos_alias - this->read_pos); // number of bytes to reach the write position 
     22: 227:  if (n==0 && this->stored_count==0) // <=> buffer is empty 
branch 0 taken 50% (fallthrough) 
branch 1 taken 50% 
branch 2 taken 100% (fallthrough) 
branch 3 taken 0% 
branch 4 taken 0% (fallthrough) 
branch 5 taken 100% 
branch 6 never executed 
branch 7 never executed 
branch 8 taken 30% (fallthrough) 
branch 9 taken 70% 
branch 10 taken 0% (fallthrough) 
branch 11 taken 100% 
branch 12 taken 38% (fallthrough) 
branch 13 taken 63% 
branch 14 taken 0% (fallthrough) 
branch 15 taken 100% 
     -: 228:  { 
     -: 229:   // no data read 
     1: 230:   return 0; 
     -: 231:  } 
     21: 232:  else if (0<n && n<size) // read is stopped before read_pos crosses over write_pos. 
branch 0 taken 100% (fallthrough) 
branch 1 taken 0% 
branch 2 taken 0% (fallthrough) 
branch 3 taken 100% 
branch 4 taken 100% (fallthrough) 
branch 5 taken 0% 
branch 6 taken 0% (fallthrough) 
branch 7 taken 100% 
branch 8 taken 70% (fallthrough) 
branch 9 taken 30% 
branch 10 taken 14% (fallthrough) 
branch 11 taken 86% 
branch 12 taken 63% (fallthrough) 
branch 13 taken 38% 
branch 14 taken 20% (fallthrough) 
branch 15 taken 80% 
     -: 233:  { 
     2: 234:   return read(reinterpret_cast<uint8*>(data), n); //less data than required. 
call 0 never executed 
call 1 never executed 
call 2 returned 100% 
call 3 returned 100% 
     -: 235:  } 
     -: 236:  // It is guaranteed here and below that read_pos never crosses-over write_pos. 
     -: 237: 
     19: 238:  if (this->read_pos + size > this->allocated_size) // going beyond the end of buffer 
branch 0 taken 0% (fallthrough) 
branch 1 taken 100% 
branch 2 taken 0% (fallthrough) 
branch 3 taken 100% 
branch 4 taken 11% (fallthrough) 
branch 5 taken 89% 
branch 6 taken 43% (fallthrough) 
branch 7 taken 57% 
     -: 239:  { 
     4: 240:   uint32 n(this->allocated_size - this->read_pos); // number of bytes to reach the end of buffer 
     -: 241:   return this->read(reinterpret_cast<uint8*>(data), n) 
     4: 242:     + this->read(reinterpret_cast<uint8*>(data)+n, size-n); 
call 0 never executed 
call 1 never executed 
call 2 never executed 
call 3 never executed 
call 4 returned 100% 
call 5 returned 100% 
call 6 returned 100% 
call 7 returned 100% 
     -: 243:  } 
     15: 244:  memcpy(reinterpret_cast<void*>(data), reinterpret_cast<void*>(this->buf+this->read_pos), size); 
     15: 245:  incrementReadPos(size); 
call 0 returned 100% 
call 1 returned 100% 
call 2 returned 100% 
call 3 returned 100% 
     15: 246:  return size; 
     -: 247: } 

Answer 1

, 당신은 파이프 c++filt 명령을 통해이 출력은 식별자를 분해 해제 할 수 있습니다.

두 번째 질문에 대해 분명히 gcov은 false가 누화되면 걱정하지 않지만 false가 될 수있는 세 가지 방법과 진실을 알 수있는 한 가지 방법을 계산합니다.

• 진정한 =>n==0 && this->stored_count==0
• 거짓 =>n!=0 && this->stored_count==0
• 거짓 =>n!=0 && this->stored_count!=0
• 거짓 =>n==0 && this->stored_count!=0

당신이 당신의 템플릿 기능을 여섯을 만드는 4 가지 방법을 확장입니다.