user: 请从给定的汇编指令推导出C源代码：

```asm
<RealIFFT>:
  endbr64
  push   %r13
  push   %r12
  mov    %rsi,%r12
  push   %rbp
  push   %rbx
  mov    %rdi,%rbx
  lea    0x0(,%rsi,8),%edi
  sub    $0x8,%rsp
  call   <safe_malloc@plt>
  lea    0x10(%rbx),%rdx
  mov    %rax,%r13
  mov    %r12,%rax
  shr    %rax
  mov    %r13,%rbp
  lea    0x1(%rax),%rsi
  cmp    %rdx,%r13
  jae    L52
  lea    0x10(%r13),%rdx
  cmp    %rdx,%rbx
  jb     L171
L52:
  test   %rax,%rax
  je     L29
  mov    %rsi,%rdx
  mov    %rbx,%rcx
  mov    %r13,%rax
  shr    %rdx
  sub    %r13,%rcx
  shl    $0x4,%rdx
  add    %r13,%rdx
  nopl   (%rax)
L104:
  movups (%rax,%rcx,1),%xmm2
  add    $0x10,%rax
  movups %xmm2,-0x10(%rax)
  cmp    %rdx,%rax
  jne    L104
  mov    %rsi,%rax
  and    $0xfffffffffffffffe,%rax
  test   $0x1,%sil
  je     L0
L71:
  mov    (%rbx,%rax,8),%rdx
  mov    %rdx,0x0(%r13,%rax,8)
L0:
  cmp    %rsi,%r12
  jbe    L166
L9:
  mov    %r12d,%ecx
  lea    0x0(%r13,%rsi,8),%rax
  movss  D6(%rip),%xmm1
  sub    %esi,%ecx
  lea    0x0(%r13,%r12,8),%rsi
  nop
L123:
  lea    (%rcx,%rcx,1),%edx
  add    $0x8,%rax
  sub    $0x1,%ecx
  movslq %edx,%rdx
  movss  (%rbx,%rdx,4),%xmm0
  movss  %xmm0,-0x8(%rax)
  movss  0x4(%rbx,%rdx,4),%xmm0
  xorps  %xmm1,%xmm0
  movss  %xmm0,-0x4(%rax)
  cmp    %rax,%rsi
  jne    L123
  mov    %r12,%rsi
  mov    %r13,%rdi
  call   <IFFT@plt>
L20:
  test   %r12,%r12
  mov    $0x4,%ecx
  lea    -0x4(,%r12,8),%rax
  cmove  %rcx,%rax
  add    %r13,%rax
  cmp    %rax,%rbx
  lea    0x0(,%r12,4),%rax
  setae  %dl
  test   %r12,%r12
  cmove  %rcx,%rax
  add    %rbx,%rax
  cmp    %rax,%r13
  setae  %al
  or     %al,%dl
  je     L184
  cmp    $0x4,%r12
  jbe    L184
  test   %r12,%r12
  mov    $0x1,%eax
  cmovne %r12,%rax
  lea    -0x1(%rax),%rdx
  mov    %rbx,%rax
  mov    %rdx,%rcx
  shr    $0x2,%rcx
  shl    $0x5,%rcx
  add    %r13,%rcx
  nopl   (%rax)
L70:
  movups 0x0(%rbp),%xmm0
  movups 0x10(%rbp),%xmm3
  add    $0x20,%rbp
  add    $0x10,%rax
  shufps $0x88,%xmm3,%xmm0
  movups %xmm0,-0x10(%rax)
  cmp    %rbp,%rcx
  jne    L70
  mov    %rdx,%rax
  and    $0xfffffffffffffffc,%rax
  movss  0x0(%r13,%rax,8),%xmm0
  lea    0x1(%rax),%rsi
  lea    0x0(,%rax,8),%rcx
  lea    0x0(,%rax,4),%rdx
  movss  %xmm0,(%rbx,%rax,4)
  cmp    %rsi,%r12
  jbe    L155
  movss  0x8(%r13,%rcx,1),%xmm0
  lea    0x2(%rax),%rsi
  movss  %xmm0,0x4(%rbx,%rdx,1)
  cmp    %r12,%rsi
  jae    L155
  movss  0x10(%r13,%rcx,1),%xmm0
  add    $0x3,%rax
  movss  %xmm0,0x8(%rbx,%rdx,1)
  cmp    %r12,%rax
  jae    L155
  movss  0x18(%r13,%rcx,1),%xmm0
  movss  %xmm0,0xc(%rbx,%rdx,1)
L155:
  add    $0x8,%rsp
  mov    %r13,%rdi
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  jmp    1090 <safe_free@plt>
  nopl   0x0(%rax)
L171:
  mov    %rbx,%rdx
  lea    0x0(%r13,%rsi,8),%rcx
  mov    %r13,%rax
  sub    %r13,%rdx
  cs nopw 0x0(%rax,%rax,1)
L31:
  movss  (%rdx,%rax,1),%xmm0
  movss  %xmm0,(%rax)
  movss  0x4(%rdx,%rax,1),%xmm0
  add    $0x8,%rax
  movss  %xmm0,-0x4(%rax)
  cmp    %rcx,%rax
  jne    L31
  cmp    %rsi,%r12
  ja     L9
  cs nopw 0x0(%rax,%rax,1)
L166:
  mov    %r12,%rsi
  mov    %r13,%rdi
  call   <IFFT@plt>
  test   %r12,%r12
  je     L155
  jmp    L20
  nopl   (%rax)
L184:
  xor    %eax,%eax
  nopw   0x0(%rax,%rax,1)
L152:
  movss  0x0(%rbp),%xmm0
  add    $0x8,%rbp
  movss  %xmm0,(%rbx,%rax,4)
  add    $0x1,%rax
  cmp    %rax,%r12
  ja     L152
  jmp    L155
L29:
  xor    %eax,%eax
  jmp    L71
```

tool_calls: name: extract_symbolic_data
arguments: data_tag: D6
data_type: byte[4]

tool: {"D6": [0x00,0x00,0x00,0x80]}

assistant: ```c
void RealIFFT(float *x, unsigned long N) {
  float *y;
  unsigned long i;
  y = (float *)safe_malloc(2 * N * sizeof(float));
  for (i = 0; i <= N / 2; i++) {
    y[2 * i] = x[2 * i];
    y[2 * i + 1] = x[2 * i + 1];
  }
  for (i = N / 2 + 1; i < N; i++) {
    int j = N - i;
    y[2 * i] = x[2 * j];
    y[2 * i + 1] = -x[2 * j + 1];
  }
  IFFT(y, N);
  for (i = 0; i < N; i++) {
    x[i] = y[2 * i];
  }
  safe_free(y);
}
```