user: What would the C source look like for the assembly code provided here?

```asm
<qsort>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbx
  sub    $0x408,%rsp
  mov    %rdi,-0x418(%rbp)
  mov    %esi,-0x41c(%rbp)
  mov    %edx,-0x420(%rbp)
  mov    %rcx,-0x428(%rbp)
  mov    %fs:0x28,%rax
  mov    %rax,-0x38(%rbp)
  xor    %eax,%eax
  cmpl   $0x31f,-0x420(%rbp)
  ja     L117
  lea    -0x360(%rbp),%r13
  jmp    L5
L117:
  mov    -0x420(%rbp),%eax
  add    $0x1,%eax
  mov    %eax,%edi
  mov    $0x0,%eax
  call   <malloc@plt>
  mov    %rax,%r13
  test   %r13,%r13
  je     L89
L5:
  mov    -0x420(%rbp),%eax
  add    %r13,%rax
  movb   $0x0,(%rax)
  movl   $0x0,-0x404(%rbp)
  movl   $0x0,-0x400(%rbp)
  mov    -0x41c(%rbp),%eax
  sub    $0x1,%eax
  mov    %eax,-0x3fc(%rbp)
L30:
  mov    -0x404(%rbp),%eax
  cltq
  mov    -0x400(%rbp,%rax,8),%r15d
  mov    -0x404(%rbp),%eax
  lea    -0x1(%rax),%edx
  mov    %edx,-0x404(%rbp)
  cltq
  mov    -0x3fc(%rbp,%rax,8),%r14d
L10:
  mov    %r15d,%r12d
  mov    %r14d,%ebx
  lea    (%r12,%rbx,1),%eax
  mov    %eax,%edx
  shr    $0x1f,%edx
  add    %edx,%eax
  sar    %eax
  imul   -0x420(%rbp),%eax
  mov    %eax,%edx
  mov    -0x418(%rbp),%rax
  lea    (%rdx,%rax,1),%rcx
  mov    -0x420(%rbp),%eax
  mov    %eax,%edx
  mov    %r13,%rsi
  mov    %rcx,%rdi
  mov    $0x0,%eax
  call   <bmove@plt>
  jmp    L82
L85:
  add    $0x1,%r12d
L82:
  mov    %r12d,%eax
  imul   -0x420(%rbp),%eax
  mov    %eax,%edx
  mov    -0x418(%rbp),%rax
  add    %rdx,%rax
  mov    -0x428(%rbp),%rdx
  mov    %r13,%rsi
  mov    %rax,%rdi
  mov    $0x0,%eax
  call   *%rdx
  test   %eax,%eax
  js     L85
  jmp    L42
L91:
  sub    $0x1,%ebx
L42:
  mov    %ebx,%eax
  imul   -0x420(%rbp),%eax
  mov    %eax,%edx
  mov    -0x418(%rbp),%rax
  add    %rdx,%rax
  mov    -0x428(%rbp),%rdx
  mov    %rax,%rsi
  mov    %r13,%rdi
  mov    $0x0,%eax
  call   *%rdx
  test   %eax,%eax
  js     L91
  cmp    %ebx,%r12d
  jg     L131
  mov    %ebx,%eax
  imul   -0x420(%rbp),%eax
  mov    %eax,%edx
  mov    -0x418(%rbp),%rax
  add    %rax,%rdx
  mov    %r12d,%eax
  imul   -0x420(%rbp),%eax
  mov    %eax,%ecx
  mov    -0x418(%rbp),%rax
  add    %rax,%rcx
  mov    -0x420(%rbp),%eax
  mov    %rcx,%rsi
  mov    %eax,%edi
  mov    $0x0,%eax
  call   <_swap@plt>
  add    $0x1,%r12d
  sub    $0x1,%ebx
L131:
  cmp    %ebx,%r12d
  jle    L82
  mov    %ebx,%edx
  sub    %r15d,%edx
  mov    %r14d,%eax
  sub    %r12d,%eax
  cmp    %eax,%edx
  jge    L145
  cmp    %r14d,%r12d
  jge    L75
  addl   $0x1,-0x404(%rbp)
  mov    -0x404(%rbp),%eax
  cltq
  mov    %r12d,-0x400(%rbp,%rax,8)
  mov    -0x404(%rbp),%eax
  cltq
  mov    %r14d,-0x3fc(%rbp,%rax,8)
L75:
  mov    %ebx,%r14d
  jmp    L125
L145:
  cmp    %ebx,%r15d
  jge    L71
  addl   $0x1,-0x404(%rbp)
  mov    -0x404(%rbp),%eax
  cltq
  mov    %r15d,-0x400(%rbp,%rax,8)
  mov    -0x404(%rbp),%eax
  cltq
  mov    %ebx,-0x3fc(%rbp,%rax,8)
L71:
  mov    %r12d,%r15d
L125:
  cmp    %r14d,%r15d
  jl     L10
  cmpl   $0x0,-0x404(%rbp)
  jns    L30
  lea    -0x360(%rbp),%rax
  cmp    %rax,%r13
  je     L109
  mov    %r13,%rdi
  call   <free@plt>
  jmp    L109
L89:
  nop
L109:
  mov    -0x38(%rbp),%rdx
  sub    %fs:0x28,%rdx
  je     L61
  call   <__stack_chk_fail@plt>
L61:
  add    $0x408,%rsp
  pop    %rbx
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  pop    %rbp
  ret
```

assistant: ```c
qsort(base, nel, width, compar) char *base;
int (*compar)();
unsigned width, nel;
{
  register char *x;
  extern char *malloc();
  register int i, j, l, r;
  struct {
    int l, r;
  } stack[20];
  int s;
  char xbuf[800];
  if (width < sizeof xbuf)
    x = xbuf;
  else if (!(x = malloc(width + 1)))
    return;
  x[width] = 0;
  s = 0;
  stack[0].l = 0;
  stack[0].r = nel - 1;
  do {
    l = stack[s].l;
    r = stack[s--].r;
    do {
      i = l;
      j = r;
      bmove(base + width * ((i + j) / 2), x, width);
      do {
        while ((*compar)(base + i * width, x) < 0)
          i++;
        while ((*compar)(x, base + j * width) < 0)
          j--;
        if (i <= j) {
          _swap(width, base + i * width, base + j * width);
          i++;
          j--;
        }
      } while (i <= j);
      if (j - l < r - i) {
        if (i < r) {
          stack[++s].l = i;
          stack[s].r = r;
        }
        r = j;
      } else {
        if (l < j) {
          stack[++s].l = l;
          stack[s].r = j;
        }
        l = i;
      }
    } while (l < r);
  } while (s >= 0);
  if (x != xbuf)
    free(x);
}
```