user: Please show me the C implementation that matches the assembly code listed below:

```asm
<packforblock40_64>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  mov    %edi,-0x64(%rbp)
  mov    %rsi,-0x70(%rbp)
  mov    %rdx,-0x78(%rbp)
  mov    -0x78(%rbp),%rax
  mov    (%rax),%rax
  mov    %rax,-0x10(%rbp)
  mov    -0x70(%rbp),%rax
  mov    (%rax),%rax
  mov    %rax,-0x8(%rbp)
  mov    -0x8(%rbp),%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    %eax,-0x60(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x4,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x28,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x60(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x4,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  sar    $0x18,%eax
  mov    %eax,-0x5c(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x8,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  shl    $0x10,%eax
  or     %eax,-0x5c(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0xc,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x38,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x5c(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0xc,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  sar    $0x8,%eax
  mov    %eax,-0x58(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x10,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x20,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x58(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x10,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x20,%edx
  mov    %edx,%ecx
  sar    %cl,%eax
  mov    %eax,-0x54(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x14,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  shl    $0x8,%eax
  or     %eax,-0x54(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x18,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x30,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x54(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x18,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  sar    $0x10,%eax
  mov    %eax,-0x50(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x1c,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  shl    $0x18,%eax
  or     %eax,-0x50(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x20,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    %eax,-0x4c(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x24,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x28,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x4c(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x24,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  sar    $0x18,%eax
  mov    %eax,-0x48(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x28,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  shl    $0x10,%eax
  or     %eax,-0x48(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x2c,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x38,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x48(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x2c,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  sar    $0x8,%eax
  mov    %eax,-0x44(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x30,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x20,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x44(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x30,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x20,%edx
  mov    %edx,%ecx
  sar    %cl,%eax
  mov    %eax,-0x40(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x34,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  shl    $0x8,%eax
  or     %eax,-0x40(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x38,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x30,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x40(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x38,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  sar    $0x10,%eax
  mov    %eax,-0x3c(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x3c,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  shl    $0x18,%eax
  or     %eax,-0x3c(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x40,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    %eax,-0x38(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x44,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x28,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x38(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x44,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  sar    $0x18,%eax
  mov    %eax,-0x34(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x48,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  shl    $0x10,%eax
  or     %eax,-0x34(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x4c,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x38,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x34(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x4c,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  sar    $0x8,%eax
  mov    %eax,-0x30(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x50,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x20,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x30(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x50,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x20,%edx
  mov    %edx,%ecx
  sar    %cl,%eax
  mov    %eax,-0x2c(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x54,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  shl    $0x8,%eax
  or     %eax,-0x2c(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x58,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x30,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x2c(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x58,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  sar    $0x10,%eax
  mov    %eax,-0x28(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x5c,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  shl    $0x18,%eax
  or     %eax,-0x28(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x60,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    %eax,-0x24(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x64,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x28,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x24(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x64,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  sar    $0x18,%eax
  mov    %eax,-0x20(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x68,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  shl    $0x10,%eax
  or     %eax,-0x20(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x6c,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x38,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x20(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x6c,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  sar    $0x8,%eax
  mov    %eax,-0x1c(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x70,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x20,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x1c(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x70,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x20,%edx
  mov    %edx,%ecx
  sar    %cl,%eax
  mov    %eax,-0x18(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x74,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  shl    $0x8,%eax
  or     %eax,-0x18(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x78,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  mov    $0x30,%edx
  mov    %edx,%ecx
  shl    %cl,%eax
  or     %eax,-0x18(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x78,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  sar    $0x10,%eax
  mov    %eax,-0x14(%rbp)
  mov    -0x8(%rbp),%rax
  add    $0x7c,%rax
  mov    (%rax),%eax
  sub    -0x64(%rbp),%eax
  shl    $0x18,%eax
  or     %eax,-0x14(%rbp)
  mov    -0x10(%rbp),%rax
  mov    -0x60(%rbp),%edx
  mov    %edx,(%rax)
  mov    -0x10(%rbp),%rax
  lea    0x4(%rax),%rdx
  mov    -0x5c(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x8(%rax),%rdx
  mov    -0x58(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0xc(%rax),%rdx
  mov    -0x54(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x10(%rax),%rdx
  mov    -0x50(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x14(%rax),%rdx
  mov    -0x4c(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x18(%rax),%rdx
  mov    -0x48(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x1c(%rax),%rdx
  mov    -0x44(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x20(%rax),%rdx
  mov    -0x40(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x24(%rax),%rdx
  mov    -0x3c(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x28(%rax),%rdx
  mov    -0x38(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x2c(%rax),%rdx
  mov    -0x34(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x30(%rax),%rdx
  mov    -0x30(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x34(%rax),%rdx
  mov    -0x2c(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x38(%rax),%rdx
  mov    -0x28(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x3c(%rax),%rdx
  mov    -0x24(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x40(%rax),%rdx
  mov    -0x20(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x44(%rax),%rdx
  mov    -0x1c(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x48(%rax),%rdx
  mov    -0x18(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x10(%rbp),%rax
  lea    0x4c(%rax),%rdx
  mov    -0x14(%rbp),%eax
  mov    %eax,(%rdx)
  mov    -0x70(%rbp),%rax
  mov    (%rax),%rax
  lea    0x80(%rax),%rdx
  mov    -0x70(%rbp),%rax
  mov    %rdx,(%rax)
  mov    -0x78(%rbp),%rax
  mov    (%rax),%rax
  lea    0x280(%rax),%rdx
  mov    -0x78(%rbp),%rax
  mov    %rdx,(%rax)
  nop
  pop    %rbp
  ret
```

assistant: ```c
void packforblock40_64(const uint64_t base, const uint64_t **pin, uint8_t **pw) {
  uint64_t *pw64 = *(uint64_t **)pw;
  const uint64_t *in = *pin;
  uint64_t w0;
  uint64_t w1;
  uint64_t w2;
  uint64_t w3;
  uint64_t w4;
  uint64_t w5;
  uint64_t w6;
  uint64_t w7;
  uint64_t w8;
  uint64_t w9;
  uint64_t w10;
  uint64_t w11;
  uint64_t w12;
  uint64_t w13;
  uint64_t w14;
  uint64_t w15;
  uint64_t w16;
  uint64_t w17;
  uint64_t w18;
  uint64_t w19;
  w0 = (in[0] - base);
  w0 |= (in[1] - base) << 40;
  w1 = (in[1] - base) >> 24;
  w1 |= (in[2] - base) << 16;
  w1 |= (in[3] - base) << 56;
  w2 = (in[3] - base) >> 8;
  w2 |= (in[4] - base) << 32;
  w3 = (in[4] - base) >> 32;
  w3 |= (in[5] - base) << 8;
  w3 |= (in[6] - base) << 48;
  w4 = (in[6] - base) >> 16;
  w4 |= (in[7] - base) << 24;
  w5 = (in[8] - base);
  w5 |= (in[9] - base) << 40;
  w6 = (in[9] - base) >> 24;
  w6 |= (in[10] - base) << 16;
  w6 |= (in[11] - base) << 56;
  w7 = (in[11] - base) >> 8;
  w7 |= (in[12] - base) << 32;
  w8 = (in[12] - base) >> 32;
  w8 |= (in[13] - base) << 8;
  w8 |= (in[14] - base) << 48;
  w9 = (in[14] - base) >> 16;
  w9 |= (in[15] - base) << 24;
  w10 = (in[16] - base);
  w10 |= (in[17] - base) << 40;
  w11 = (in[17] - base) >> 24;
  w11 |= (in[18] - base) << 16;
  w11 |= (in[19] - base) << 56;
  w12 = (in[19] - base) >> 8;
  w12 |= (in[20] - base) << 32;
  w13 = (in[20] - base) >> 32;
  w13 |= (in[21] - base) << 8;
  w13 |= (in[22] - base) << 48;
  w14 = (in[22] - base) >> 16;
  w14 |= (in[23] - base) << 24;
  w15 = (in[24] - base);
  w15 |= (in[25] - base) << 40;
  w16 = (in[25] - base) >> 24;
  w16 |= (in[26] - base) << 16;
  w16 |= (in[27] - base) << 56;
  w17 = (in[27] - base) >> 8;
  w17 |= (in[28] - base) << 32;
  w18 = (in[28] - base) >> 32;
  w18 |= (in[29] - base) << 8;
  w18 |= (in[30] - base) << 48;
  w19 = (in[30] - base) >> 16;
  w19 |= (in[31] - base) << 24;
  pw64[0] = w0;
  pw64[1] = w1;
  pw64[2] = w2;
  pw64[3] = w3;
  pw64[4] = w4;
  pw64[5] = w5;
  pw64[6] = w6;
  pw64[7] = w7;
  pw64[8] = w8;
  pw64[9] = w9;
  pw64[10] = w10;
  pw64[11] = w11;
  pw64[12] = w12;
  pw64[13] = w13;
  pw64[14] = w14;
  pw64[15] = w15;
  pw64[16] = w16;
  pw64[17] = w17;
  pw64[18] = w18;
  pw64[19] = w19;
  *pin += 32;
  *pw += 160;
}
```