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

```asm
<gradient3Dx_float>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x38,%rsp
  mov    %rdi,%rbp
  mov    %rsi,%rbx
  mov    %rdx,%r15
  mov    %rdx,0x28(%rsp)
  mov    (%rsi),%r13d
  imul   0x4(%rsi),%r13d
  lea    0x0(,%r13,4),%edi
  call   <mallocf@plt>
  mov    %rax,%r12
  mov    (%rbx),%edi
  call   <mallocf@plt>
  mov    %rax,%rdi
  cmpl   $0x0,0x8(%rbx)
  jle    L217
  movslq %r13d,%rax
  shl    $0x2,%rax
  mov    %rax,0x20(%rsp)
  mov    %r15,0x18(%rsp)
  movl   $0x0,0x10(%rsp)
  movl   $0x0,0x14(%rsp)
  movl   $0x0,0xc(%rsp)
  movl   $0x0,0x8(%rsp)
  mov    $0x0,%r15d
  movss  D71(%rip),%xmm2
  movss  D5(%rip),%xmm6
  movss  D13(%rip),%xmm5
  pxor   %xmm4,%xmm4
  movss  D62(%rip),%xmm3
  jmp    L48
L60:
  mov    0xc(%rsp),%eax
  imul   %r11d,%eax
  test   %r11d,%r11d
  jle    L31
  mov    0x10(%rsp),%esi
  cltq
  lea    (%r12,%rax,4),%rcx
  movslq %r14d,%rax
  lea    (%r12,%rax,4),%rdx
  mov    $0x0,%eax
  movss  D71(%rip),%xmm7
  movss  D5(%rip),%xmm8
  mov    0x28(%rsp),%r8
L177:
  movss  (%rcx,%rax,4),%xmm1
  movaps %xmm1,%xmm0
  mulss  %xmm7,%xmm0
  mulss  %xmm8,%xmm1
  addss  %xmm1,%xmm0
  movaps %xmm7,%xmm1
  mulss  (%rdx,%rax,4),%xmm1
  addss  %xmm1,%xmm0
  movss  %xmm0,(%r8,%rax,4)
  add    $0x1,%rax
  cmp    %rsi,%rax
  jne    L177
  jmp    L204
L0:
  mov    0x14(%rsp),%ecx
  imul   %r13d,%ecx
  mov    0xc(%rsp),%edx
  imul   %r13d,%edx
  mov    0x10(%rsp),%eax
  sub    %r13d,%eax
  test   %r13d,%r13d
  jle    L31
  mov    %r13d,%r9d
  movslq %ecx,%rcx
  lea    (%r12,%rcx,4),%r8
  movslq %edx,%rdx
  lea    (%r12,%rdx,4),%rsi
  movslq %r14d,%rdx
  lea    (%r12,%rdx,4),%rcx
  cltq
  mov    0x28(%rsp),%rdx
  lea    (%rdx,%rax,4),%rdx
  mov    $0x0,%eax
  movss  D71(%rip),%xmm1
  movss  D5(%rip),%xmm8
L185:
  movaps %xmm1,%xmm0
  mulss  (%r8,%rax,4),%xmm0
  movaps %xmm8,%xmm7
  mulss  (%rsi,%rax,4),%xmm7
  addss  %xmm7,%xmm0
  movaps %xmm1,%xmm7
  mulss  (%rcx,%rax,4),%xmm7
  addss  %xmm7,%xmm0
  movss  %xmm0,(%rdx,%rax,4)
  add    $0x1,%rax
  cmp    %r9,%rax
  jne    L185
L204:
  mov    0x8(%rbx),%eax
  sub    $0x1,%eax
  cmp    %r15d,%eax
  je     L53
L31:
  mov    0x8(%rsp),%eax
  add    $0x1,%eax
  cmp    $0x4,%eax
  mov    $0x0,%edx
  cmovge %edx,%eax
  add    $0x1,%r15d
  add    %r13d,0x10(%rsp)
  mov    0x20(%rsp),%rcx
  add    %rcx,0x18(%rsp)
  mov    0xc(%rsp),%esi
  mov    %esi,0x14(%rsp)
  cmp    %r15d,0x8(%rbx)
  jle    L217
  mov    0x8(%rsp),%esi
  mov    %esi,0xc(%rsp)
  mov    %eax,0x8(%rsp)
L48:
  mov    0x10(%rsp),%r11d
  mov    0x8(%rsp),%r14d
  imul   %r13d,%r14d
  mov    0x4(%rbx),%eax
  test   %eax,%eax
  jle    L85
  mov    $0x0,%r10d
L197:
  test   %r10d,%r10d
  mov    $0x1,%edx
  cmovg  %r10d,%edx
  sub    $0x1,%edx
  mov    %r10d,%r9d
  add    $0x1,%r10d
  mov    (%rbx),%ecx
  imul   %ecx,%edx
  add    %r11d,%edx
  mov    %ecx,%esi
  imul   %r9d,%esi
  add    %r11d,%esi
  sub    $0x1,%eax
  cmp    %r10d,%eax
  cmovg  %r10d,%eax
  imul   %ecx,%eax
  add    %r11d,%eax
  test   %ecx,%ecx
  jle    L189
  movslq %edx,%rdx
  lea    0x0(%rbp,%rdx,4),%r8
  movslq %esi,%rsi
  lea    0x0(%rbp,%rsi,4),%rsi
  cltq
  lea    0x0(%rbp,%rax,4),%rcx
  mov    $0x0,%edx
L30:
  movaps %xmm2,%xmm1
  mulss  (%r8,%rdx,4),%xmm1
  movss  %xmm1,(%rdi,%rdx,4)
  movaps %xmm6,%xmm0
  mulss  (%rsi,%rdx,4),%xmm0
  addss  %xmm1,%xmm0
  movss  %xmm0,(%rdi,%rdx,4)
  movaps %xmm2,%xmm1
  mulss  (%rcx,%rdx,4),%xmm1
  addss  %xmm0,%xmm1
  movss  %xmm1,(%rdi,%rdx,4)
  mov    (%rbx),%eax
  add    $0x1,%rdx
  cmp    %edx,%eax
  jg     L30
  imul   %eax,%r9d
  add    %r14d,%r9d
  test   %eax,%eax
  jle    L189
  movslq %r9d,%r9
  lea    (%r12,%r9,4),%rsi
  mov    $0x0,%edx
L99:
  test   %edx,%edx
  mov    $0x1,%ecx
  cmovg  %edx,%ecx
  sub    $0x1,%ecx
  movslq %ecx,%rcx
  movaps %xmm5,%xmm0
  mulss  (%rdi,%rcx,4),%xmm0
  movaps %xmm4,%xmm1
  mulss  (%rdi,%rdx,4),%xmm1
  addss  %xmm1,%xmm0
  sub    $0x1,%eax
  lea    0x1(%rdx),%ecx
  cmp    %ecx,%eax
  cmovg  %ecx,%eax
  cltq
  movaps %xmm3,%xmm1
  mulss  (%rdi,%rax,4),%xmm1
  addss  %xmm1,%xmm0
  movss  %xmm0,(%rsi,%rdx,4)
  mov    (%rbx),%eax
  add    $0x1,%rdx
  cmp    %edx,%eax
  jg     L99
L189:
  mov    0x4(%rbx),%eax
  cmp    %eax,%r10d
  jl     L197
L85:
  cmp    $0x1,%r15d
  je     L60
  jg     L0
  mov    0x8(%rbx),%eax
  sub    $0x1,%eax
  cmp    %r15d,%eax
  jne    L31
  mov    0xc(%rsp),%eax
  imul   %r13d,%eax
  test   %r13d,%r13d
  jle    L31
L180:
  cltq
  lea    (%r12,%rax,4),%rdx
  movslq %r14d,%r14
  lea    (%r12,%r14,4),%rcx
  mov    $0x0,%eax
  movss  D71(%rip),%xmm7
  movss  D5(%rip),%xmm9
  mov    0x18(%rsp),%rsi
L137:
  movss  (%rcx,%rax,4),%xmm1
  movaps %xmm7,%xmm0
  mulss  (%rdx,%rax,4),%xmm0
  movaps %xmm1,%xmm8
  mulss  %xmm9,%xmm8
  addss  %xmm8,%xmm0
  mulss  %xmm7,%xmm1
  addss  %xmm1,%xmm0
  movss  %xmm0,(%rsi,%rax,4)
  add    $0x1,%rax
  cmp    %eax,%r13d
  jg     L137
  jmp    L31
L217:
  call   <free@plt>
  mov    %r12,%rdi
  call   <free@plt>
  add    $0x38,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L53:
  mov    0xc(%rsp),%eax
  imul   %r13d,%eax
  jmp    L180
```

tool_calls: name: retrieve_data
arguments: tag: D71
type: byte[4]
name: retrieve_data
arguments: tag: D5
type: byte[4]
name: retrieve_data
arguments: tag: D13
type: byte[4]
name: retrieve_data
arguments: tag: D62
type: byte[4]

tool: {"D71": [0x00,0x00,0x40,0x3e]}

tool: {"D5": [0x00,0x00,0x20,0x3f]}

tool: {"D13": [0x00,0x00,0x00,0xbf]}

tool: {"D62": [0x00,0x00,0x00,0x3f]}

assistant: ```c
void gradient3Dx_float(float *I, int *sizeI, float *Ix) {
  int x, y, z;
  int xp, xn, yp, yn;
  int i;
  int indexn, indexc, indexp;
  float *Irow, *Islices;
  int nSlice;
  int offsetz, offset_slice;
  int slice_select = 0;
  int slice_select_p1 = 0;
  int slice_select_p2 = 0;
  const float smoothfilter[3] = {0.187500f, 0.625000f, 0.187500f};
  const float derivafilter[3] = {-0.5f, 0.0f, 0.5f};
  nSlice = sizeI[0] * sizeI[1];
  Islices = mallocf(4 * nSlice);
  Irow = mallocf(sizeI[0]);
  for (z = 0; z < sizeI[2]; z++) {
    offsetz = nSlice * z;
    offset_slice = nSlice * slice_select;
    for (y = 0; y < sizeI[1]; y++) {
      yn = ((y - 1) > (0) ? (y - 1) : (0));
      yp = ((y + 1) < (sizeI[1] - 1) ? (y + 1) : (sizeI[1] - 1));
      indexn = yn * sizeI[0] + offsetz;
      indexc = y * sizeI[0] + offsetz;
      indexp = yp * sizeI[0] + offsetz;
      for (x = 0; x < sizeI[0]; x++) {
        Irow[x] = smoothfilter[0] * I[indexn + x];
        Irow[x] += smoothfilter[1] * I[indexc + x];
        Irow[x] += smoothfilter[2] * I[indexp + x];
      }
      indexc = y * sizeI[0] + offset_slice;
      for (x = 0; x < sizeI[0]; x++) {
        xn = ((x - 1) > (0) ? (x - 1) : (0));
        xp = ((x + 1) < (sizeI[0] - 1) ? (x + 1) : (sizeI[0] - 1));
        Islices[indexc + x] = derivafilter[0] * Irow[xn] + derivafilter[1] * Irow[x] + derivafilter[2] * Irow[xp];
      }
    }
    if (z == 1) {
      indexn = slice_select_p1 * nSlice;
      indexc = slice_select_p1 * nSlice;
      indexp = slice_select * nSlice;
      for (i = 0; i < nSlice; i++) {
        Ix[i] = smoothfilter[0] * Islices[i + indexn] + smoothfilter[1] * Islices[i + indexc] + smoothfilter[2] * Islices[i + indexp];
      }
    } else if (z > 1) {
      indexn = slice_select_p2 * nSlice;
      indexc = slice_select_p1 * nSlice;
      indexp = slice_select * nSlice;
      offsetz = nSlice * (z - 1);
      for (i = 0; i < nSlice; i++) {
        Ix[offsetz + i] = smoothfilter[0] * Islices[i + indexn] + smoothfilter[1] * Islices[i + indexc] + smoothfilter[2] * Islices[i + indexp];
      }
    }
    if (z == (sizeI[2] - 1)) {
      indexn = slice_select_p1 * nSlice;
      indexc = slice_select * nSlice;
      indexp = slice_select * nSlice;
      offsetz = nSlice * z;
      for (i = 0; i < nSlice; i++) {
        Ix[offsetz + i] = smoothfilter[0] * Islices[i + indexn] + smoothfilter[1] * Islices[i + indexc] + smoothfilter[2] * Islices[i + indexp];
      }
    }
    slice_select_p2 = slice_select_p1;
    slice_select_p1 = slice_select;
    slice_select++;
    if (slice_select > 3) {
      slice_select = 0;
    }
  }
  free(Irow);
  free(Islices);
}
```