user: 请将这段汇编代码片段转换成等效的C代码：

```asm
<trackball>:
  endbr64
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x50,%rsp
  mov    %rdi,%rbx
  movss  %xmm2,0x8(%rsp)
  movss  %xmm3,0xc(%rsp)
  mov    %fs:0x28,%rax
  mov    %rax,0x48(%rsp)
  xor    %eax,%eax
  ucomiss %xmm3,%xmm1
  setnp  %al
  mov    $0x0,%edx
  cmovne %edx,%eax
  test   %al,%al
  je     L10
  ucomiss %xmm2,%xmm0
  setnp  %al
  cmovne %edx,%eax
  test   %al,%al
  jne    L34
L10:
  pxor   %xmm2,%xmm2
  cvtss2sd %xmm1,%xmm2
  movq   %xmm2,%r13
  pxor   %xmm5,%xmm5
  cvtss2sd %xmm0,%xmm5
  movq   %xmm5,%r12
  movapd %xmm5,%xmm1
  mov    D22(%rip),%rax
  movq   %rax,%xmm0
  mov    $0x3,%eax
  call   <tb_project_to_sphere@plt>
  pxor   %xmm2,%xmm2
  cvtsi2ss %eax,%xmm2
  lea    0x24(%rsp),%rbp
  cvtss2sd %xmm2,%xmm2
  movq   %r13,%xmm1
  movq   %r12,%xmm0
  mov    %rbp,%rdi
  mov    $0x3,%eax
  call   <vset@plt>
  pxor   %xmm2,%xmm2
  cvtss2sd 0xc(%rsp),%xmm2
  movq   %xmm2,%r13
  pxor   %xmm6,%xmm6
  cvtss2sd 0x8(%rsp),%xmm6
  movq   %xmm6,%r14
  movapd %xmm6,%xmm1
  mov    D22(%rip),%rax
  movq   %rax,%xmm0
  mov    $0x3,%eax
  call   <tb_project_to_sphere@plt>
  pxor   %xmm2,%xmm2
  cvtsi2ss %eax,%xmm2
  lea    0x30(%rsp),%r12
  cvtss2sd %xmm2,%xmm2
  movq   %r13,%xmm1
  movq   %r14,%xmm0
  mov    %r12,%rdi
  mov    $0x3,%eax
  call   <vset@plt>
  lea    0x18(%rsp),%rdx
  mov    %rbp,%rsi
  mov    %r12,%rdi
  mov    $0x0,%eax
  call   <vcross@plt>
  lea    0x3c(%rsp),%r13
  mov    %r13,%rdx
  mov    %r12,%rsi
  mov    %rbp,%rdi
  mov    $0x0,%eax
  call   <vsub@plt>
  mov    %r13,%rdi
  mov    $0x0,%eax
  call   <vlength@plt>
  pxor   %xmm0,%xmm0
  cvtsi2ss %eax,%xmm0
  cvtss2sd %xmm0,%xmm0
  divsd  D54(%rip),%xmm0
  cvtsd2ss %xmm0,%xmm0
  comiss D33(%rip),%xmm0
  jbe    L48
  movss  D33(%rip),%xmm0
L17:
  cvtss2sd %xmm0,%xmm0
  call   <asin@plt>
  addsd  %xmm0,%xmm0
  cvtsd2ss %xmm0,%xmm0
  cvtss2sd %xmm0,%xmm0
  lea    0x18(%rsp),%rdi
  mov    %rbx,%rsi
  mov    $0x1,%eax
  call   <axis_to_quat@plt>
L50:
  mov    0x48(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L13
  add    $0x50,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  ret
L34:
  mov    $0x0,%eax
  call   <vzero@plt>
  movl   $0x3f800000,0xc(%rbx)
  jmp    L50
L48:
  movss  D21(%rip),%xmm1
  comiss %xmm0,%xmm1
  jbe    L17
  movaps %xmm1,%xmm0
  jmp    L17
L13:
  call   <__stack_chk_fail@plt>
```

tool_calls: name: unpack_data
arguments: data_label: D22
type_guessed: byte[8]
name: unpack_data
arguments: data_label: D54
type_guessed: byte[8]
name: unpack_data
arguments: data_label: D33
type_guessed: f32
name: unpack_data
arguments: data_label: D21
type_guessed: byte[4]

tool: {"D22": [0x00,0x00,0x00,0xa0,0x99,0x99,0xe9,0x3f]}

tool: {"D54": [0x9a,0x99,0x99,0x99,0x99,0x99,0xf9,0x3f]}

tool: D33: 1

tool: {"D21": [0x00,0x00,0x80,0xbf]}

assistant: ```c
void trackball(float *q, float p1x, float p1y, float p2x, float p2y) {
  float a[3l];
  float phi;
  float p1[3l];
  float p2[3l];
  float d[3l];
  float t;
  if ((p1x == p2x)) {
    if ((p1y == p2y)) {
      vzero(q);
      q[(signed long int)3] = (float)1.000000;
      return;
    }
  }
  float return_value_tb_project_to_sphere$1;
  return_value_tb_project_to_sphere$1 = tb_project_to_sphere((float)8.000000e-1, p1x, p1y);
  vset(p1, p1x, p1y, return_value_tb_project_to_sphere$1);
  float return_value_tb_project_to_sphere$2;
  return_value_tb_project_to_sphere$2 = tb_project_to_sphere((float)8.000000e-1, p2x, p2y);
  vset(p2, p2x, p2y, return_value_tb_project_to_sphere$2);
  vcross(p2, p1, a);
  vsub(p1, p2, d);
  float return_value_vlength$3;
  return_value_vlength$3 = vlength(d);
  t = (float)((double)return_value_vlength$3 / (2.000000 * 8.000000e-1));
  if (t > 1.000000f)
    t = (float)1.000000;
  if (t < -1.000000f)
    t = (float)-1.000000;
  double return_value_asin$4;
  return_value_asin$4 = asin((double)t);
  phi = (float)(2.000000 * return_value_asin$4);
  axis_to_quat(a, phi, q);
}
```