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

```asm
<c5matrix>:
  endbr64
  push   %r15
  mov    %esi,%eax
  push   %r14
  sub    %edi,%eax
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x78,%rsp
  mov    %edi,0x2c(%rsp)
  lea    0x1(%rax),%edi
  mov    0xb8(%rsp),%ebx
  shl    $0x3,%rdi
  mov    %esi,0x50(%rsp)
  mov    %edx,0x54(%rsp)
  mov    %ecx,0x38(%rsp)
  mov    %r8d,0x3c(%rsp)
  mov    %r9d,0x18(%rsp)
  call   <malloc@plt>
  test   %rax,%rax
  je     L136
  movslq 0x2c(%rsp),%rdx
  mov    %rax,%rcx
  mov    %rdx,%rsi
  shl    $0x3,%rdx
  sub    %rdx,%rcx
  mov    %rcx,0x68(%rsp)
  cmp    %esi,0x50(%rsp)
  jl     L17
  mov    0x54(%rsp),%esi
  mov    0x38(%rsp),%edx
  mov    %rax,0x30(%rsp)
  mov    0xc8(%rsp),%eax
  sub    0xc0(%rsp),%eax
  sub    %esi,%edx
  add    $0x1,%eax
  add    $0x1,%edx
  mov    %eax,0x1c(%rsp)
  shl    $0x3,%rdx
  mov    %rdx,0x58(%rsp)
  movslq %esi,%rdx
  mov    0x3c(%rsp),%esi
  shl    $0x3,%rdx
  neg    %rdx
  mov    %rdx,0x60(%rsp)
  mov    0x18(%rsp),%edx
  sub    %esi,%edx
  add    $0x1,%edx
  shl    $0x3,%rdx
  mov    %rdx,0x40(%rsp)
  movslq %esi,%rdx
  shl    $0x3,%rdx
  neg    %rdx
  mov    %rdx,0x48(%rsp)
  mov    %ebx,%edx
  sub    0xb0(%rsp),%edx
  add    $0x1,%edx
  shl    $0x3,%rdx
  mov    %rdx,0x8(%rsp)
  movslq 0xb0(%rsp),%rdx
  shl    $0x3,%rdx
  neg    %rdx
  mov    %rdx,0x10(%rsp)
L16:
  mov    0x58(%rsp),%rdi
  call   <malloc@plt>
  test   %rax,%rax
  je     L82
  mov    0x60(%rsp),%rdx
  mov    %rax,0x20(%rsp)
  mov    0x30(%rsp),%rsi
  movslq 0xc0(%rsp),%r12
  add    %rax,%rdx
  mov    0x54(%rsp),%eax
  mov    %rdx,(%rsi)
  mov    %eax,0x28(%rsp)
  cmp    %eax,0x38(%rsp)
  jl     L75
L96:
  mov    0x40(%rsp),%rdi
  call   <malloc@plt>
  mov    %rax,%r13
  test   %rax,%rax
  je     L143
  mov    0x48(%rsp),%rax
  mov    0x20(%rsp),%rdx
  add    %r13,%rax
  mov    %rax,(%rdx)
  mov    0x3c(%rsp),%eax
  mov    %eax,0x4(%rsp)
  cmp    %eax,0x18(%rsp)
  jl     L125
L1:
  mov    0x8(%rsp),%rdi
  call   <malloc@plt>
  mov    %rax,%rcx
  test   %rax,%rax
  je     L48
  mov    0x10(%rsp),%rax
  mov    0xb0(%rsp),%r14d
  mov    %rcx,%r15
  mov    0x1c(%rsp),%ebp
  add    %rcx,%rax
  mov    %rax,0x0(%r13)
  cmp    %r14d,%ebx
  jl     L87
  cs nopw 0x0(%rax,%rax,1)
L60:
  mov    %rbp,%rdi
  call   <malloc@plt>
  test   %rax,%rax
  je     L8
  sub    %r12,%rax
  add    $0x1,%r14d
  add    $0x8,%r15
  mov    %rax,-0x8(%r15)
  cmp    %r14d,%ebx
  jge    L60
L87:
  addl   $0x1,0x4(%rsp)
  add    $0x8,%r13
  mov    0x4(%rsp),%eax
  cmp    %eax,0x18(%rsp)
  jge    L1
L125:
  addl   $0x1,0x28(%rsp)
  mov    0x28(%rsp),%eax
  addq   $0x8,0x20(%rsp)
  cmp    %eax,0x38(%rsp)
  jge    L96
L75:
  addl   $0x1,0x2c(%rsp)
  mov    0x2c(%rsp),%eax
  addq   $0x8,0x30(%rsp)
  cmp    %eax,0x50(%rsp)
  jge    L16
L17:
  mov    0x68(%rsp),%rax
  add    $0x78,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopw   0x0(%rax,%rax,1)
L8:
  movq   $0x0,(%r15)
L136:
  mov    $0x14,%edi
  call   <exit@plt>
L48:
  movq   $0x0,0x0(%r13)
  jmp    L136
L143:
  mov    0x20(%rsp),%rax
  movq   $0x0,(%rax)
  jmp    L136
L82:
  mov    0x30(%rsp),%rax
  movq   $0x0,(%rax)
  jmp    L136
```

assistant: ```c
unsigned char *****c5matrix(ncoll, ncolh, nql, nqh, nzl, nzh, nrl, nrh, ncl, nch)
int ncoll, ncolh, nrl, nrh, ncl, nch, nzl, nzh, nql, nqh;
{
  unsigned char *****m;
  int i, j, k, l;
  m = (unsigned char *****)malloc((unsigned)(ncolh - ncoll + 1) * sizeof(unsigned char ****));
  if (!m)
    exit(20);
  m -= ncoll;
  for (k = ncoll; k <= ncolh; k++) {
    m[k] = (unsigned char ****)malloc((unsigned)(nqh - nql + 1) * sizeof(unsigned char ***));
    if (!m[k])
      exit(20);
    m[k] -= nql;
    for (i = nql; i <= nqh; i++) {
      m[k][i] = (unsigned char ***)malloc((unsigned)(nzh - nzl + 1) * sizeof(unsigned char **));
      if (!m[k][i])
        exit(20);
      m[k][i] -= nzl;
      for (j = nzl; j <= nzh; j++) {
        m[k][i][j] = (unsigned char **)malloc((unsigned)(nrh - nrl + 1) * sizeof(unsigned char *));
        if (!m[k][i][j])
          exit(20);
        m[k][i][j] -= nrl;
        for (l = nrl; l <= nrh; l++) {
          m[k][i][j][l] = (unsigned char *)malloc((unsigned)(nch - ncl + 1) * sizeof(unsigned char));
          if (!m[k][i][j][l])
            exit(20);
          m[k][i][j][l] -= ncl;
        }
      }
    }
  }
  return m;
}
```