user: Converte this assembly snippet into its equivalent C code:

```asm
<lsx_dfst>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x28,%rsp
  mov    %edi,%r14d
  mov    %rsi,%r12
  mov    %rdx,%rbx
  mov    %rcx,0x10(%rsp)
  mov    %r8,0x8(%rsp)
  mov    (%rcx),%r13d
  lea    0x0(,%r13,8),%eax
  cmp    %edi,%eax
  jl     L26
L61:
  mov    0x10(%rsp),%rax
  mov    0x4(%rax),%r15d
  lea    (%r15,%r15,1),%eax
  cmp    %r14d,%eax
  jl     L140
L135:
  cmp    $0x2,%r14d
  jle    L66
  mov    %r14d,%eax
  sar    %eax
  mov    %eax,0x1c(%rsp)
  mov    %r14d,%ebp
  sar    $0x2,%ebp
  cmp    $0x7,%r14d
  jle    L212
  movslq %eax,%rcx
  lea    -0x8(,%rcx,8),%rdx
  mov    %ebp,%esi
  movslq %r14d,%rax
  sub    %rcx,%rax
  lea    (%r12,%rax,8),%rcx
  mov    $0x1,%eax
L209:
  movsd  (%r12,%rax,8),%xmm2
  movsd  (%rcx,%rdx,1),%xmm5
  movapd %xmm2,%xmm0
  subsd  %xmm5,%xmm0
  movsd  (%r12,%rdx,1),%xmm1
  movsd  (%rcx,%rax,8),%xmm4
  movapd %xmm1,%xmm3
  subsd  %xmm4,%xmm3
  addsd  %xmm5,%xmm2
  movsd  %xmm2,(%r12,%rax,8)
  addsd  %xmm4,%xmm1
  movsd  %xmm1,(%r12,%rdx,1)
  movapd %xmm0,%xmm1
  addsd  %xmm3,%xmm1
  movsd  %xmm1,(%rbx,%rax,8)
  subsd  %xmm3,%xmm0
  movsd  %xmm0,(%rbx,%rdx,1)
  add    $0x1,%rax
  sub    $0x8,%rdx
  cmp    %rsi,%rax
  jne    L209
L212:
  movslq %ebp,%rax
  lea    (%r12,%rax,8),%rax
  mov    %r14d,%edx
  sub    %ebp,%edx
  movslq %edx,%rdx
  lea    (%r12,%rdx,8),%rdx
  movsd  (%rax),%xmm0
  subsd  (%rdx),%xmm0
  movsd  %xmm0,(%rbx)
  movsd  (%rax),%xmm0
  addsd  (%rdx),%xmm0
  movsd  %xmm0,(%rax)
  mov    0x1c(%rsp),%edi
  movslq %edi,%rax
  movsd  (%r12,%rax,8),%xmm0
  movsd  %xmm0,(%r12)
  movslq %r13d,%r13
  mov    0x8(%rsp),%rax
  lea    (%rax,%r13,8),%rax
  mov    %rax,(%rsp)
  mov    %rax,%rcx
  mov    %r15d,%edx
  mov    %r12,%rsi
  mov    %edi,%r13d
  call   <dstsub@plt>
  cmp    $0x4,%r13d
  jg     L45
  cmpl   $0x4,0x1c(%rsp)
  je     L98
  movslq %r14d,%rax
  movsd  0x8(%r12),%xmm0
  subsd  (%r12),%xmm0
  movsd  %xmm0,-0x8(%r12,%rax,8)
  movsd  0x8(%r12),%xmm0
  addsd  (%r12),%xmm0
  movsd  %xmm0,0x8(%r12)
  jmp    L10
L26:
  mov    %edi,%r13d
  sar    $0x3,%r13d
  mov    %r8,%rdx
  mov    %rcx,%rsi
  mov    %r13d,%edi
  call   <makewt@plt>
  jmp    L61
L140:
  mov    %r14d,%r15d
  sar    %r15d
  movslq %r13d,%rax
  mov    0x8(%rsp),%rdi
  lea    (%rdi,%rax,8),%rdx
  mov    0x10(%rsp),%rsi
  mov    %r15d,%edi
  call   <makect@plt>
  jmp    L135
L45:
  mov    0x10(%rsp),%rax
  lea    0x8(%rax),%rsi
  mov    %r12,%rdx
  mov    0x1c(%rsp),%r13d
  mov    %r13d,%edi
  call   <bitrv2@plt>
  mov    0x8(%rsp),%rdx
  mov    %r12,%rsi
  mov    %r13d,%edi
  call   <cftfsub@plt>
  mov    (%rsp),%rcx
  mov    %r15d,%edx
  mov    %r12,%rsi
  mov    %r13d,%edi
  call   <rftfsub@plt>
L32:
  movslq %r14d,%rax
  movsd  0x8(%r12),%xmm0
  subsd  (%r12),%xmm0
  movsd  %xmm0,-0x8(%r12,%rax,8)
  movsd  0x8(%r12),%xmm0
  addsd  (%r12),%xmm0
  movsd  %xmm0,0x8(%r12)
  mov    0x1c(%rsp),%edx
  sub    $0x2,%edx
  movslq %edx,%rax
  lea    0x1(%rdx,%rdx,1),%edx
  movslq %edx,%rdx
  lea    (%r12,%rdx,8),%rdx
  movq   D12(%rip),%xmm1
L9:
  movsd  (%r12,%rax,8),%xmm0
  subsd  0x8(%r12,%rax,8),%xmm0
  movsd  %xmm0,(%rdx)
  movsd  (%r12,%rax,8),%xmm0
  xorpd  %xmm1,%xmm0
  subsd  0x8(%r12,%rax,8),%xmm0
  movsd  %xmm0,-0x10(%rdx)
  sub    $0x2,%rax
  sub    $0x20,%rdx
  cmp    $0x1,%eax
  jg     L9
L10:
  cmp    $0x1,%ebp
  jle    L219
  mov    $0x2,%r13d
  jmp    L214
L98:
  mov    0x8(%rsp),%rdx
  mov    %r12,%rsi
  mov    $0x4,%edi
  call   <cftfsub@plt>
  jmp    L32
L154:
  mov    0x10(%rsp),%rax
  lea    0x8(%rax),%rsi
  mov    %rbx,%rdx
  mov    %ebp,%edi
  call   <bitrv2@plt>
  mov    0x8(%rsp),%rdx
  mov    %rbx,%rsi
  mov    %ebp,%edi
  call   <cftfsub@plt>
  mov    (%rsp),%rcx
  mov    %r15d,%edx
  mov    %rbx,%rsi
  mov    %ebp,%edi
  call   <rftfsub@plt>
L84:
  mov    %r14d,%eax
  sub    %r13d,%eax
  cltq
  movsd  0x8(%rbx),%xmm0
  subsd  (%rbx),%xmm0
  movsd  %xmm0,(%r12,%rax,8)
  movslq %r13d,%rax
  movsd  (%rbx),%xmm0
  addsd  0x8(%rbx),%xmm0
  movsd  %xmm0,(%r12,%rax,8)
L67:
  lea    0x0(,%r13,4),%eax
  cltq
  lea    0x0(,%rax,8),%rsi
  movslq %r13d,%rcx
  sub    %rcx,%rax
  lea    (%r12,%rax,8),%rdx
  shl    $0x4,%rcx
  mov    $0x2,%eax
L111:
  movsd  (%rbx,%rax,8),%xmm0
  xorpd  D12(%rip),%xmm0
  subsd  0x8(%rbx,%rax,8),%xmm0
  movsd  %xmm0,(%rdx)
  movsd  (%rbx,%rax,8),%xmm0
  subsd  0x8(%rbx,%rax,8),%xmm0
  movsd  %xmm0,(%rdx,%rcx,1)
  add    $0x2,%rax
  add    %rsi,%rdx
  cmp    %eax,%ebp
  jg     L111
  add    %r13d,%r13d
  mov    %ebp,%edi
  sar    %edi
  cmp    $0x3,%ebp
  jle    L38
  movslq %ebp,%rcx
  mov    %rcx,%rdx
  shl    $0x4,%rdx
  add    %rbx,%rdx
  lea    (%rbx,%rcx,8),%rax
  lea    -0x2(%rdi),%esi
  add    %rcx,%rsi
  lea    0x8(%rbx,%rsi,8),%rsi
  neg    %rcx
  shl    $0x3,%rcx
L159:
  movsd  -0x8(%rdx),%xmm0
  addsd  0x8(%rax),%xmm0
  movsd  %xmm0,0x8(%rax,%rcx,1)
  movsd  -0x8(%rdx),%xmm0
  subsd  0x8(%rax),%xmm0
  movsd  %xmm0,-0x8(%rdx,%rcx,1)
  sub    $0x8,%rdx
  add    $0x8,%rax
  cmp    %rsi,%rax
  jne    L159
  add    %edi,%ebp
  movslq %ebp,%rbp
  movsd  (%rbx,%rbp,8),%xmm0
  movsd  %xmm0,(%rbx)
  mov    %edi,%ebp
L214:
  mov    (%rsp),%rcx
  mov    %r15d,%edx
  mov    %rbx,%rsi
  mov    %ebp,%edi
  call   <dstsub@plt>
  cmp    $0x4,%ebp
  jg     L154
  je     L92
  mov    %r14d,%eax
  sub    %r13d,%eax
  cltq
  movsd  0x8(%rbx),%xmm0
  subsd  (%rbx),%xmm0
  movsd  %xmm0,(%r12,%rax,8)
  movslq %r13d,%rax
  movsd  (%rbx),%xmm0
  addsd  0x8(%rbx),%xmm0
  movsd  %xmm0,(%r12,%rax,8)
  cmp    $0x2,%ebp
  jg     L67
  add    %r13d,%r13d
  mov    %ebp,%edi
  sar    %edi
L38:
  lea    (%rdi,%rbp,1),%eax
  cltq
  movsd  (%rbx,%rax,8),%xmm0
  movsd  %xmm0,(%rbx)
L199:
  movsd  (%rbx),%xmm0
  movslq %r13d,%r13
  movsd  %xmm0,(%r12,%r13,8)
L66:
  movq   $0x0,(%r12)
  add    $0x28,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L92:
  mov    0x8(%rsp),%rdx
  mov    %rbx,%rsi
  mov    $0x4,%edi
  call   <cftfsub@plt>
  jmp    L84
L219:
  mov    $0x2,%r13d
  jmp    L199
```

tool_calls: name: read_data
arguments: tag: D12
type_guessed: byte[16]

tool: {"D12": [0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00]}

assistant: ```c
void lsx_dfst(int n, double *a, double *t, int *ip, double *w) {
  int j, k, l, m, mh, nw, nc;
  double xr, xi, yr, yi;
  nw = ip[0];
  if (n > (nw << 3)) {
    nw = n >> 3;
    makewt(nw, ip, w);
  }
  nc = ip[1];
  if (n > (nc << 1)) {
    nc = n >> 1;
    makect(nc, ip, w + nw);
  }
  if (n > 2) {
    m = n >> 1;
    mh = m >> 1;
    for (j = 1; j < mh; j++) {
      k = m - j;
      xr = a[j] + a[n - j];
      xi = a[j] - a[n - j];
      yr = a[k] + a[n - k];
      yi = a[k] - a[n - k];
      a[j] = xr;
      a[k] = yr;
      t[j] = xi + yi;
      t[k] = xi - yi;
    }
    t[0] = a[mh] - a[n - mh];
    a[mh] += a[n - mh];
    a[0] = a[m];
    dstsub(m, a, nc, w + nw);
    if (m > 4) {
      bitrv2(m, ip + 2, a);
      cftfsub(m, a, w);
      rftfsub(m, a, nc, w + nw);
    } else if (m == 4) {
      cftfsub(m, a, w);
    }
    a[n - 1] = a[1] - a[0];
    a[1] = a[0] + a[1];
    for (j = m - 2; j >= 2; j -= 2) {
      a[2 * j + 1] = a[j] - a[j + 1];
      a[2 * j - 1] = -a[j] - a[j + 1];
    }
    l = 2;
    m = mh;
    while (m >= 2) {
      dstsub(m, t, nc, w + nw);
      if (m > 4) {
        bitrv2(m, ip + 2, t);
        cftfsub(m, t, w);
        rftfsub(m, t, nc, w + nw);
      } else if (m == 4) {
        cftfsub(m, t, w);
      }
      a[n - l] = t[1] - t[0];
      a[l] = t[0] + t[1];
      k = 0;
      for (j = 2; j < m; j += 2) {
        k += l << 2;
        a[k - l] = -t[j] - t[j + 1];
        a[k + l] = t[j] - t[j + 1];
      }
      l <<= 1;
      mh = m >> 1;
      for (j = 1; j < mh; j++) {
        k = m - j;
        t[j] = t[m + k] + t[m + j];
        t[k] = t[m + k] - t[m + j];
      }
      t[0] = t[m + mh];
      m = mh;
    }
    a[l] = t[0];
  }
  a[0] = 0;
}
```