user: 下面的汇编指令对应的C源代码是什么:

```asm
<substring>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x28,%rsp
  mov    %rdi,0x8(%rsp)
  test   %rdi,%rdi
  je     L46
  mov    %esi,%r13d
  mov    %edx,%r14d
  mov    $0x0,%r15d
  cmp    %edx,%esi
  jge    L128
  mov    $0x1,%edi
  call   <malloc@plt>
  mov    %rax,%r15
  mov    0x8(%rsp),%rax
  cmpb   $0x0,(%rax)
  je     L33
  test   %r14d,%r14d
  jle    L56
  mov    %rax,%rbp
  movl   $0x1,0x10(%rsp)
  mov    $0x0,%r12d
  mov    $0x0,%ebx
  jmp    L181
L46:
  lea    D15(%rip),%rdi
  call   <puts@plt>
  mov    0x8(%rsp),%r15
  jmp    L128
L152:
  cmp    0x10(%rsp),%r12d
  je     L180
L17:
  movslq %r12d,%r12
  movb   $0x0,(%r15,%r12,1)
L39:
  cmp    %ebx,%r13d
  jg     L28
L128:
  mov    %r15,%rax
  add    $0x28,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L180:
  mov    0x10(%rsp),%r14d
  lea    0x1(%r14),%edi
  call   <malloc@plt>
  mov    %rax,%rbp
  test   %r14d,%r14d
  jle    L52
  lea    -0x1(%r14),%eax
  lea    0x1(%rbp,%rax,1),%rsi
  mov    %rbp,%rax
  mov    %r15,%rcx
  sub    %rbp,%rcx
L154:
  movzbl (%rcx,%rax,1),%edx
  mov    %dl,(%rax)
  add    $0x1,%rax
  cmp    %rsi,%rax
  jne    L154
L52:
  mov    %r15,%rdi
  call   <free@plt>
  mov    %rbp,%r15
  jmp    L17
L56:
  mov    $0x0,%r12d
  mov    $0x0,%ebx
  jmp    L17
L36:
  mov    %r15,%rdi
  call   <free@plt>
  mov    0x18(%rsp),%r15
  mov    0x14(%rsp),%eax
  mov    %eax,0x10(%rsp)
L132:
  movzbl 0x0(%rbp),%edx
  movslq %r12d,%rax
  mov    %dl,(%r15,%rax,1)
  add    $0x1,%r12d
L136:
  add    $0x1,%ebx
  add    $0x1,%rbp
  cmpb   $0x0,0x0(%rbp)
  je     L39
  cmp    %ebx,%r14d
  je     L152
L181:
  cmp    %ebx,%r13d
  jg     L136
  cmp    0x10(%rsp),%r12d
  jne    L132
  mov    0x10(%rsp),%eax
  lea    (%rax,%rax,1),%ecx
  mov    %ecx,0x14(%rsp)
  mov    %ecx,%edi
  call   <malloc@plt>
  mov    %rax,%rcx
  mov    %rax,0x18(%rsp)
  mov    0x10(%rsp),%eax
  test   %eax,%eax
  jle    L36
  lea    -0x1(%rax),%eax
  lea    0x1(%rcx,%rax,1),%rsi
  mov    %rcx,%rax
  mov    %r15,%rdi
  sub    %rcx,%rdi
  mov    %rdi,%rcx
L157:
  movzbl (%rcx,%rax,1),%edx
  mov    %dl,(%rax)
  add    $0x1,%rax
  cmp    %rsi,%rax
  jne    L157
  jmp    L36
L33:
  mov    $0x0,%ebx
  jmp    L39
L28:
  lea    0x1(%rbx),%edx
  mov    %r13d,%ecx
  mov    0x8(%rsp),%rsi
  lea    D18(%rip),%rdi
  call   <printf@plt>
  mov    $0x0,%r15d
  jmp    L128
```

tool_calls: name: parse_data
arguments: label: D15
type: string
name: parse_data
arguments: label: D18
type: string

tool: D15: substring() was given a null message!

tool: D18: %s has a length of %d but was given a start index of %d


assistant: ```c
char *substring(char *message, int start, int end) {
  if (message == NULL) {
    puts("substring() was given a null message!");
    return NULL;
  }
  if (start == end || start > end) {
    return NULL;
  }
  int messIndex = 0, strIndex = 0, size = 1;
  char *string = (char *)malloc(sizeof(char));
  while (message[messIndex] != 0) {
    if (messIndex >= end) {
      if (strIndex == size) {
        char *tmpString = (char *)malloc(sizeof(char) * (size) + 1);
        for (int i = 0; i < size; i++) {
          tmpString[i] = string[i];
        }
        size = size + 1;
        free(string);
        string = tmpString;
      }
      string[strIndex] = 0;
      break;
    } else if (messIndex >= start) {
      if (strIndex == size) {
        char *tmpString = (char *)malloc(sizeof(char) * (size * 2));
        for (int i = 0; i < size; i++) {
          tmpString[i] = string[i];
        }
        size = size * 2;
        free(string);
        string = tmpString;
      }
      string[strIndex] = message[messIndex];
      strIndex++;
    }
    messIndex++;
  }
  if (messIndex < start) {
    printf("%s has a length of %d but was given a start index of %d\n", message, messIndex + 1, start);
    return NULL;
  }
  return string;
}
```