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

```asm
<stringcmp$link93>:
  endbr64
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  mov    %rdi,%r12
  mov    %rsi,%r13
  call   <strlen@plt>
  mov    %rax,%rbx
  mov    %r13,%rdi
  call   <strlen@plt>
  mov    %rax,%rdx
  mov    $0x1,%eax
  cmp    %edx,%ebx
  jne    11c6 <stringcmp$link93+0x8d>
  test   %ebx,%ebx
  jle    11ba <stringcmp$link93+0x81>
  lea    -0x1(%rbx),%r14d
  mov    $0x0,%ebx
  jmp    1179 <stringcmp$link93+0x40>
  mov    %rax,%rbx
  mov    $0x0,%eax
  call   <__ctype_toupper_loc@plt>
  cltq
  movsbq (%r12,%rbx,1),%rdx
  mov    (%rax),%rax
  mov    (%rax,%rdx,4),%ebp
  mov    $0x0,%eax
  call   <__ctype_toupper_loc@plt>
  cltq
  movsbq 0x0(%r13,%rbx,1),%rdx
  mov    (%rax),%rax
  cmp    %ebp,(%rax,%rdx,4)
  jne    11c1 <stringcmp$link93+0x88>
  lea    0x1(%rbx),%rax
  cmp    %r14,%rbx
  jne    1176 <stringcmp$link93+0x3d>
  mov    $0x0,%eax
  jmp    11c6 <stringcmp$link93+0x8d>
  mov    $0x0,%eax
  jmp    11c6 <stringcmp$link93+0x8d>
  mov    $0x1,%eax
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  ret
```

assistant: ```c
signed int stringcmp$link93(char *a$link91, char *b$link92) {
  signed int i$link94;
  signed int s$link96;
  signed int l$link97;
  unsigned long int return_value_strlen$1$link244;
  return_value_strlen$1$link244 = strlen(a$link91);
  s$link96 = (signed int)return_value_strlen$1$link244;
  unsigned long int return_value_strlen$2$link246;
  return_value_strlen$2$link246 = strlen(b$link92);
  l$link97 = (signed int)return_value_strlen$2$link246;
  if (!(s$link96 == l$link97))
    return 1;
  i$link94 = 0;
  signed int tmp_statement_expression$3$link247;
  signed int tmp_if_expr$5$link249;
  const signed int **return_value___ctype_toupper_loc$6$link250;
  signed int tmp_statement_expression$7;
  signed int tmp_if_expr$9;
  const signed int **return_value___ctype_toupper_loc$10;
  while (!(i$link94 >= s$link96)) {
    signed int __res$link99;
    if ((_Bool)0) {
      if ((_Bool)0) {
        signed int __c$link102 = (signed int)a$link91[(signed long int)i$link94];
        if (!(__c$link102 < -128)) {
          if (__c$link102 > 255)
            goto __CPROVER_DUMP_L3;
        } else {
        __CPROVER_DUMP_L3:;
          tmp_if_expr$5$link249 = __c$link102;
          goto __CPROVER_DUMP_L5;
        }
        const signed int **return_value___ctype_toupper_loc$4$link248;
        return_value___ctype_toupper_loc$4$link248 = __ctype_toupper_loc();
        tmp_if_expr$5$link249 = (*return_value___ctype_toupper_loc$4$link248)[(signed long int)__c$link102];
      __CPROVER_DUMP_L5:;
        __res$link99 = tmp_if_expr$5$link249;
      } else
        __res$link99 = toupper((signed int)a$link91[(signed long int)i$link94]);
    } else {
      return_value___ctype_toupper_loc$6$link250 = __ctype_toupper_loc();
      __res$link99 = (*return_value___ctype_toupper_loc$6$link250)[(signed long int)(signed int)a$link91[(signed long int)i$link94]];
    }
    tmp_statement_expression$3$link247 = __res$link99;
    signed int __res;
    if ((_Bool)0) {
      if ((_Bool)0) {
        signed int __c = (signed int)b$link92[(signed long int)i$link94];
        if (!(__c < -128)) {
          if (__c > 255)
            goto __CPROVER_DUMP_L10;
        } else {
        __CPROVER_DUMP_L10:;
          tmp_if_expr$9 = __c;
          goto __CPROVER_DUMP_L12;
        }
        const signed int **return_value___ctype_toupper_loc$8;
        return_value___ctype_toupper_loc$8 = __ctype_toupper_loc();
        tmp_if_expr$9 = (*return_value___ctype_toupper_loc$8)[(signed long int)__c];
      __CPROVER_DUMP_L12:;
        __res = tmp_if_expr$9;
      } else
        __res = toupper((signed int)b$link92[(signed long int)i$link94]);
    } else {
      return_value___ctype_toupper_loc$10 = __ctype_toupper_loc();
      __res = (*return_value___ctype_toupper_loc$10)[(signed long int)(signed int)b$link92[(signed long int)i$link94]];
    }
    tmp_statement_expression$7 = __res;
    if (!(tmp_statement_expression$3$link247 == tmp_statement_expression$7))
      return 1;
    i$link94 = i$link94 + 1;
  }
  return 0;
}
```