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

```asm
<renduarene>:
  endbr64
  push   %r15
  mov    %rdi,%rsi
  push   %r14
  push   %r13
  push   %r12
  mov    %rdi,%r12
  push   %rbp
  push   %rbx
  sub    $0x318,%rsp
  mov    %rdi,(%rsp)
  lea    0x10(%rsp),%rdi
  lea    0x308(%rsp),%r8
  mov    %rdi,%r11
  mov    %fs:0x28,%rax
  mov    %rax,0x308(%rsp)
  xor    %eax,%eax
  mov    %rdi,0x8(%rsp)
  nopw   0x0(%rax,%rax,1)
L252:
  mov    %rsi,%rdx
  lea    -0x26(%rsi),%rcx
  xor    %eax,%eax
  add    $0x26,%rsi
  jmp    L84
  nop
L436:
  add    $0x1,%rax
  cmp    $0x26,%rax
  je     L174
L84:
  cmpb   $0x23,(%rdx,%rax,1)
  jne    L436
  cmpb   $0x23,0x1(%rcx,%rax,1)
  jne    L436
  cmpb   $0x23,0x1(%rsi,%rax,1)
  jne    L436
  cmpb   $0x23,-0x1(%rsi,%rax,1)
  jne    L436
  cmpb   $0x23,-0x1(%rcx,%rax,1)
  jne    L436
  movb   $0x20,(%rdx,%rax,1)
  movb   $0x20,(%rdi,%rax,1)
  add    $0x1,%rax
  cmp    $0x26,%rax
  jne    L84
  xchg   %ax,%ax
L174:
  add    $0x26,%rdi
  cmp    %rdi,%r8
  jne    L252
  xor    %ecx,%ecx
  mov    $0x80001,%r14d
  movabs $0x2000000001,%r8
  nopl   0x0(%rax,%rax,1)
L116:
  mov    %r14,%r10
  mov    $0xaac0,%ebx
  mov    $0x8ac0,%r13d
  xor    %edx,%edx
  shr    %cl,%r10
  shr    %cl,%rbx
  lea    -0x26(%r12),%rbp
  mov    %r12,%rsi
  shr    %cl,%r13
  add    $0x26,%r12
  and    $0x1,%r10d
  mov    %r11,%rdi
  and    $0x1,%ebx
  and    $0x1,%r13d
  jmp    L175
  nopl   (%rax)
L470:
  cmp    $0x23,%al
  je     L309
  cmp    $0x2e,%al
  jne    L71
  movb   $0x2e,(%rdi)
L71:
  bt     %r9,%r8
  jb     L166
L127:
  test   %rdx,%rdx
  je     L103
  cmp    $0x25,%rdx
  je     L506
L418:
  add    $0x1,%rdx
  add    $0x1,%rsi
  add    $0x1,%rdi
  cmp    $0x26,%rdx
  je     L294
L175:
  movzbl (%rsi),%eax
  mov    %edx,%r9d
  cmp    $0x42,%al
  je     L533
  jle    L470
  cmp    $0x43,%al
  je     L516
  cmp    $0x4d,%al
  jne    L71
  bt     %r9,%r8
  movb   $0x4d,(%rdi)
  jae    L127
  nop
L166:
  test   %r10,%r10
  jne    L144
  movb   $0xba,(%rdi)
  jmp    L127
  nopw   0x0(%rax,%rax,1)
L144:
  mov    %edx,%eax
  test   %edx,%edx
  jne    L486
  cmp    $0x13,%ecx
  jne    L486
  movb   $0xc8,0x2e2(%rsp)
L103:
  test   %r13b,%r13b
  je     L418
  movb   $0xcc,(%r11)
  jmp    L418
L486:
  cmp    $0x25,%eax
  jne    L127
  test   %ecx,%ecx
  jne    L127
  movb   $0xbb,0x35(%rsp)
L506:
  test   %bl,%bl
  je     L418
  movb   $0xb9,0x25(%r11)
L294:
  add    $0x1,%ecx
  add    $0x26,%r11
  cmp    $0x14,%ecx
  jne    L116
  mov    (%rsp),%rbx
  mov    0x10(%rsp),%rax
  mov    %rax,(%rbx)
  mov    0x300(%rsp),%rax
  lea    0x8(%rbx),%rdi
  and    $0xfffffffffffffff8,%rdi
  mov    %rax,0x2f0(%rbx)
  mov    %rbx,%rax
  mov    0x8(%rsp),%rsi
  sub    %rdi,%rax
  lea    0x2f8(%rax),%ecx
  sub    %rax,%rsi
  shr    $0x3,%ecx
  rep movsq %ds:(%rsi),%es:(%rdi)
  mov    0x308(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L271
  add    $0x318,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopl   0x0(%rax,%rax,1)
L516:
  movb   $0x43,(%rdi)
  jmp    L71
  nopl   0x0(%rax,%rax,1)
L309:
  cmpb   $0x23,0x0(%rbp,%rdx,1)
  movzbl 0x1(%rsi),%eax
  movzbl (%r12,%rdx,1),%r15d
  je     L326
  cmp    $0x23,%al
  je     L415
  cmp    $0x23,%r15b
  je     L167
  cmpb   $0x23,-0x1(%rsi)
  jne    L71
  movb   $0xcd,(%rdi)
  jmp    L71
L533:
  movb   $0x4,(%rdi)
  jmp    L71
  nopl   0x0(%rax,%rax,1)
L326:
  cmp    $0x23,%al
  je     L139
  cmp    $0x23,%r15b
  je     L498
  cmpb   $0x23,-0x1(%rsi)
  jne    L93
  movb   $0xbc,(%rdi)
  nopw   0x0(%rax,%rax,1)
L93:
  cmpb   $0x23,-0x1(%rsi)
  je     L71
  movb   $0xba,(%rdi)
  jmp    L71
  nopw   0x0(%rax,%rax,1)
L415:
  cmp    $0x23,%r15b
  je     L594
  cmpb   $0x23,-0x1(%rsi)
  jne    L304
  movb   $0xcd,(%rdi)
L304:
  cmpb   $0x23,-0x1(%rsi)
  je     L71
  movb   $0xcd,(%rdi)
  jmp    L71
  nopl   0x0(%rax)
L167:
  cmpb   $0x23,-0x1(%rsi)
  jne    L93
  movb   $0xbb,(%rdi)
  jmp    L93
  nopl   0x0(%rax,%rax,1)
L139:
  cmp    $0x23,%r15b
  je     L562
  cmpb   $0x23,-0x1(%rsi)
  je     L512
  movb   $0xc8,(%rdi)
L512:
  cmpb   $0x23,-0x1(%rsi)
  jne    L71
  movb   $0xca,(%rdi)
  jmp    L71
  nopl   0x0(%rax)
L594:
  cmpb   $0x23,-0x1(%rsi)
  je     L213
  movb   $0xc9,(%rdi)
L213:
  cmpb   $0x23,-0x1(%rsi)
  jne    L71
  movb   $0xcb,(%rdi)
  jmp    L71
  nopl   0x0(%rax,%rax,1)
L498:
  cmpb   $0x23,-0x1(%rsi)
  je     L417
  movb   $0xba,(%rdi)
L417:
  cmpb   $0x23,-0x1(%rsi)
  jne    L71
  movb   $0xb9,(%rdi)
  jmp    L71
L562:
  cmpb   $0x23,-0x1(%rsi)
  je     L293
  movb   $0xcc,(%rdi)
L293:
  cmpb   $0x23,-0x1(%rsi)
  jne    L71
  movb   $0xce,(%rdi)
  jmp    L71
L271:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
void renduarene(char terrain[20][38]) {
  int i, j;
  char betterterrain[20][38];
  for (i = 0; i < 20; i++) {
    for (j = 0; j < 38; j++) {
      if (terrain[i][j] == '#' && terrain[i - 1][j + 1] == '#' && terrain[i + 1][j + 1] == '#' && terrain[i + 1][j - 1] == '#' && terrain[i - 1][j - 1] == '#') {
        terrain[i][j] = ' ';
        betterterrain[i][j] = ' ';
      }
    }
  }
  for (i = 0; i < 20; i++) {
    for (j = 0; j < 38; j++) {
      switch (terrain[i][j]) {
      case '#':
        if (terrain[i - 1][j] != '#' && terrain[i][j + 1] == '#' && terrain[i + 1][j] == '#' && terrain[i][j - 1] != '#') {
          betterterrain[i][j] = (char)0xC9;
        }
        if (terrain[i - 1][j] != '#' && terrain[i][j + 1] != '#' && terrain[i + 1][j] == '#' && terrain[i][j - 1] == '#') {
          betterterrain[i][j] = (char)0xBB;
        }
        if (terrain[i - 1][j] == '#' && terrain[i][j + 1] == '#' && terrain[i + 1][j] != '#' && terrain[i][j - 1] != '#') {
          betterterrain[i][j] = (char)0xC8;
        }
        if (terrain[i - 1][j] == '#' && terrain[i][j + 1] != '#' && terrain[i + 1][j] != '#' && terrain[i][j - 1] == '#') {
          betterterrain[i][j] = (char)0xBC;
        }
        if (terrain[i - 1][j] != '#' && terrain[i][j + 1] == '#' && terrain[i + 1][j] != '#' && terrain[i][j - 1] == '#') {
          betterterrain[i][j] = (char)0xCD;
        }
        if (terrain[i - 1][j] == '#' && terrain[i][j + 1] != '#' && terrain[i + 1][j] == '#' && terrain[i][j - 1] != '#') {
          betterterrain[i][j] = (char)0xBA;
        }
        if (terrain[i - 1][j] == '#' && terrain[i][j + 1] != '#' && terrain[i + 1][j] == '#' && terrain[i][j - 1] == '#') {
          betterterrain[i][j] = (char)0xB9;
        }
        if (terrain[i - 1][j] == '#' && terrain[i][j + 1] == '#' && terrain[i + 1][j] != '#' && terrain[i][j - 1] == '#') {
          betterterrain[i][j] = (char)0xCA;
        }
        if (terrain[i - 1][j] != '#' && terrain[i][j + 1] == '#' && terrain[i + 1][j] == '#' && terrain[i][j - 1] == '#') {
          betterterrain[i][j] = (char)0xCB;
        }
        if (terrain[i - 1][j] == '#' && terrain[i][j + 1] == '#' && terrain[i + 1][j] == '#' && terrain[i][j - 1] != '#') {
          betterterrain[i][j] = (char)0xCC;
        }
        if (terrain[i - 1][j] == '#' && terrain[i][j + 1] == '#' && terrain[i + 1][j] == '#' && terrain[i][j - 1] == '#') {
          betterterrain[i][j] = (char)0xCE;
        }
        if (terrain[i - 1][j] != '#' && terrain[i][j + 1] != '#' && terrain[i + 1][j] != '#' && terrain[i][j - 1] == '#') {
          betterterrain[i][j] = (char)0xCD;
        }
        if (terrain[i - 1][j] != '#' && terrain[i][j + 1] == '#' && terrain[i + 1][j] != '#' && terrain[i][j - 1] != '#') {
          betterterrain[i][j] = (char)0xCD;
        }
        if (terrain[i - 1][j] != '#' && terrain[i][j + 1] != '#' && terrain[i + 1][j] == '#' && terrain[i][j - 1] != '#') {
          betterterrain[i][j] = (char)0xBA;
        }
        if (terrain[i - 1][j] == '#' && terrain[i][j + 1] != '#' && terrain[i + 1][j] != '#' && terrain[i][j - 1] != '#') {
          betterterrain[i][j] = (char)0xBA;
        }
        break;
      case '.':
        betterterrain[i][j] = '.';
        break;
      case 'C':
        betterterrain[i][j] = 'C';
        break;
      case 'M':
        betterterrain[i][j] = 'M';
        break;
      case 'B':
        betterterrain[i][j] = (char)0x4;
        break;
      }
      if ((j == 0 || j == 37) && (i != 0 && i != 19)) {
        betterterrain[i][j] = (char)0xBA;
      }
      if (j == 0 && i == 19) {
        betterterrain[i][j] = (char)0xC8;
      }
      if (j == 37 && i == 0) {
        betterterrain[i][j] = (char)0xBB;
      }
      if (j == 0 && (i == 6 || i == 7 || i == 9 || i == 11 || i == 15)) {
        betterterrain[i][j] = (char)0xCC;
      }
      if (j == 37 && (i == 6 || i == 7 || i == 9 || i == 11 || i == 13 || i == 15)) {
        betterterrain[i][j] = (char)0xB9;
      }
    }
  }
  for (i = 0; i < 20; i++) {
    for (j = 0; j < 38; j++) {
      terrain[i][j] = betterterrain[i][j];
    }
  }
}
```