user: What is the c source code of the assembly code below:

```asm
<infixToPostfix>:
  endbr64
  push   %r15
  mov    %rdi,%r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x8,%rsp
  call   <strlen@plt>
  mov    %eax,%edi
  call   <createStack@plt>
  test   %rax,%rax
  je     L58
  movsbl (%r15),%edi
  mov    %rax,%rbx
  test   %dil,%dil
  je     L50
  mov    %r15,%r13
  mov    $0xffffffff,%r14d
  jmp    L177
  nopl   (%rax)
L77:
  movzbl 0x0(%r13),%edx
  add    $0x1,%r14d
  movslq %r14d,%rax
  mov    %dl,(%r15,%rax,1)
L68:
  movsbl 0x1(%r13),%edi
  add    $0x1,%r13
  test   %dil,%dil
  je     L194
L177:
  call   <isOperand@plt>
  test   %rax,%rax
  jne    L77
  movzbl 0x0(%r13),%eax
  cmp    $0x28,%al
  je     L123
  movslq %r14d,%rbp
  cmp    $0x29,%al
  jne    L116
  jmp    L66
  nopl   (%rax)
L203:
  movsbl 0x0(%r13),%edi
  add    $0x1,%rbp
  call   <Prec@plt>
  mov    %rbx,%rdi
  mov    %rax,%r12
  call   <peek@plt>
  movsbl %al,%edi
  call   <Prec@plt>
  cmp    %rax,%r12
  jg     L76
  mov    %rbx,%rdi
  call   <pop@plt>
  mov    %al,(%r15,%rbp,1)
L116:
  mov    %rbx,%rdi
  mov    %ebp,%r14d
  call   <isEmpty@plt>
  test   %eax,%eax
  je     L203
L76:
  movsbl 0x0(%r13),%esi
  mov    %rbx,%rdi
  add    $0x1,%r13
  call   <push@plt>
  movsbl 0x0(%r13),%edi
  test   %dil,%dil
  jne    L177
L194:
  movslq %r14d,%r14
  lea    0x1(%r15,%r14,1),%rbp
  jmp    L16
  nopw   0x0(%rax,%rax,1)
L174:
  mov    %rbx,%rdi
  add    $0x1,%rbp
  call   <pop@plt>
  mov    %al,-0x1(%rbp)
L16:
  mov    %rbx,%rdi
  call   <isEmpty@plt>
  test   %eax,%eax
  je     L174
  movb   $0x0,0x0(%rbp)
  mov    %r15,%rsi
  lea    D6(%rip),%rdi
  call   <printf@plt>
  xor    %eax,%eax
L78:
  add    $0x8,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nop
L200:
  mov    %rbx,%rdi
  add    $0x1,%rbp
  call   <peek@plt>
  cmp    $0x28,%al
  je     L137
  mov    %rbx,%rdi
  call   <pop@plt>
  mov    %al,(%r15,%rbp,1)
L66:
  mov    %rbx,%rdi
  mov    %ebp,%r14d
  call   <isEmpty@plt>
  test   %eax,%eax
  je     L200
L137:
  mov    %rbx,%rdi
  call   <isEmpty@plt>
  test   %eax,%eax
  jne    L46
  mov    %rbx,%rdi
  call   <peek@plt>
  cmp    $0x28,%al
  jne    L58
L46:
  mov    %rbx,%rdi
  call   <pop@plt>
  jmp    L68
L123:
  mov    $0x28,%esi
  mov    %rbx,%rdi
  call   <push@plt>
  jmp    L68
L58:
  mov    $0xffffffff,%eax
  jmp    L78
L50:
  mov    $0xffffffff,%r14d
  jmp    L194
```

tool_calls: name: disassemble_data
arguments: label: D6
data_type: string

tool: D6: %sn

assistant: ```c
int infixToPostfix(char *exp) {
  int i, k;
  struct Stack *stack = createStack(strlen(exp));
  if (!stack)
    return -1;
  for (i = 0, k = -1; exp[i]; ++i) {
    if (isOperand(exp[i]))
      exp[++k] = exp[i];
    else if (exp[i] == '(')
      push(stack, exp[i]);
    else if (exp[i] == ')') {
      while (!isEmpty(stack) && peek(stack) != '(')
        exp[++k] = pop(stack);
      if (!isEmpty(stack) && peek(stack) != '(')
        return -1;
      else
        pop(stack);
    } else {
      while (!isEmpty(stack) && Prec(exp[i]) <= Prec(peek(stack)))
        exp[++k] = pop(stack);
      push(stack, exp[i]);
    }
  }
  while (!isEmpty(stack))
    exp[++k] = pop(stack);
  exp[++k] = '\0';
  printf("%sn", exp);
  return 0;
}
```