user: 下面的汇编指令对应的C源代码是什么：

```asm
<test_collapse>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x20,%rsp
  movl   $0x0,-0x1c(%rbp)
  jmp    L127
L480:
  addl   $0x1,-0x1c(%rbp)
L127:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L480
  movl   $0x0,-0x1c(%rbp)
  jmp    L372
L229:
  addl   $0x1,-0x1c(%rbp)
L372:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L229
  movl   $0x0,-0x1c(%rbp)
  jmp    L104
L186:
  addl   $0x1,-0x1c(%rbp)
L104:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L186
  movl   $0x0,-0x1c(%rbp)
  jmp    L356
L425:
  addl   $0x1,-0x1c(%rbp)
L356:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L425
  movl   $0x0,-0x1c(%rbp)
  jmp    L443
L463:
  addl   $0x1,-0x1c(%rbp)
L443:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L463
  movl   $0x0,-0x1c(%rbp)
  jmp    L83
L102:
  addl   $0x1,-0x1c(%rbp)
L83:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L102
  movl   $0x0,-0x1c(%rbp)
  jmp    L57
L344:
  addl   $0x1,-0x1c(%rbp)
L57:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L344
  movl   $0x0,-0x1c(%rbp)
  jmp    L396
L410:
  addl   $0x1,-0x1c(%rbp)
L396:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L410
  movl   $0x0,-0x1c(%rbp)
  jmp    L308
L192:
  addl   $0x1,-0x1c(%rbp)
L308:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L192
  movl   $0x0,-0x1c(%rbp)
  jmp    L352
L200:
  addl   $0x1,-0x1c(%rbp)
L352:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L200
  movl   $0x0,-0x1c(%rbp)
  jmp    L188
L319:
  addl   $0x1,-0x1c(%rbp)
L188:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L319
  movl   $0x0,-0x1c(%rbp)
  jmp    L388
L432:
  addl   $0x1,-0x1c(%rbp)
L388:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L432
  movl   $0x0,-0x18(%rbp)
  jmp    L167
L107:
  movl   $0x0,-0x14(%rbp)
  jmp    L239
L397:
  movl   $0x0,-0x10(%rbp)
  jmp    L118
L136:
  movl   $0x0,-0xc(%rbp)
  jmp    L391
L100:
  mov    $0x0,%eax
  call   <foo@plt>
  addl   $0x1,-0xc(%rbp)
L391:
  cmpl   $0xf,-0xc(%rbp)
  jle    L100
  addl   $0x1,-0x10(%rbp)
L118:
  cmpl   $0xf,-0x10(%rbp)
  jle    L136
  addl   $0x1,-0x14(%rbp)
L239:
  cmpl   $0xf,-0x14(%rbp)
  jle    L397
  addl   $0x1,-0x18(%rbp)
L167:
  cmpl   $0xf,-0x18(%rbp)
  jle    L107
  movl   $0x0,-0x1c(%rbp)
  jmp    L208
L345:
  addl   $0x1,-0x1c(%rbp)
L208:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L345
  movl   $0x0,-0x1c(%rbp)
  jmp    L173
L112:
  addl   $0x1,-0x1c(%rbp)
L173:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L112
  movl   $0x0,-0x1c(%rbp)
  jmp    L59
L40:
  addl   $0x1,-0x1c(%rbp)
L59:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L40
  movl   $0x0,-0x1c(%rbp)
  jmp    L39
L265:
  addl   $0x1,-0x1c(%rbp)
L39:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L265
  movl   $0x0,-0x1c(%rbp)
  jmp    L282
L20:
  addl   $0x1,-0x1c(%rbp)
L282:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L20
  movl   $0x0,-0x1c(%rbp)
  jmp    L49
L417:
  addl   $0x1,-0x1c(%rbp)
L49:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L417
  movl   $0x0,-0x1c(%rbp)
  jmp    L244
L366:
  movl   $0x0,-0x8(%rbp)
  jmp    L398
L399:
  movl   $0x0,-0x4(%rbp)
  jmp    L361
L269:
  mov    -0x8(%rbp),%eax
  add    %eax,-0x1c(%rbp)
  addl   $0x1,-0x4(%rbp)
L361:
  cmpl   $0xf,-0x4(%rbp)
  jle    L269
  addl   $0x1,-0x8(%rbp)
L398:
  cmpl   $0xf,-0x8(%rbp)
  jle    L399
  addl   $0x1,-0x1c(%rbp)
L244:
  cmpl   $0xf,-0x1c(%rbp)
  jle    L366
  nop
  nop
  leave
  ret
```

assistant: ```c
void test_collapse() {
  int i;
#pragma omp target parallel for simd collapse
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse()
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(,
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(, )
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse 4)
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(4
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(4,
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(4, )
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(4)
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(4 4)
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(4, , 4)
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(4)
  for (int i1 = 0; i1 < 16; ++i1)
    for (int i2 = 0; i2 < 16; ++i2)
      for (int i3 = 0; i3 < 16; ++i3)
        for (int i4 = 0; i4 < 16; ++i4)
          foo();
#pragma omp target parallel for simd collapse(4, 8)
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(2.5)
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(foo())
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(-5)
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(0)
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(5 - 5)
  for (i = 0; i < 16; ++i)
    ;
#pragma omp target parallel for simd collapse(2) firstprivate(i)
  for (i = 0; i < 16; ++i)
    for (int j = 0; j < 16; ++j)
#pragma omp for reduction(+ : i, j)
      for (int k = 0; k < 16; ++k)
        i += j;
}
```