user: 请从给定的汇编指令推导出C源代码:

```asm
<sc_add>:
  endbr64
  push   %r15
  mov    %rdx,%r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  mov    %rsi,%rbx
  sub    $0x78,%rsp
  mov    %rdi,0x28(%rsp)
  mov    %rsi,%rdi
  call   <load_3@plt>
  lea    0x2(%rbx),%rdi
  mov    %eax,%r13d
  call   <load_4@plt>
  lea    0x5(%rbx),%rdi
  and    $0x1fffff,%r13d
  mov    %eax,(%rsp)
  call   <load_3@plt>
  lea    0x7(%rbx),%rdi
  mov    %eax,0x10(%rsp)
  call   <load_4@plt>
  lea    0xa(%rbx),%rdi
  mov    %eax,0x30(%rsp)
  call   <load_4@plt>
  lea    0xd(%rbx),%rdi
  mov    %eax,0x34(%rsp)
  call   <load_3@plt>
  lea    0xf(%rbx),%rdi
  mov    %eax,0x38(%rsp)
  call   <load_4@plt>
  lea    0x12(%rbx),%rdi
  mov    %eax,0x3c(%rsp)
  call   <load_3@plt>
  lea    0x15(%rbx),%rdi
  mov    %eax,0x40(%rsp)
  call   <load_3@plt>
  lea    0x17(%rbx),%rdi
  mov    %eax,0x44(%rsp)
  call   <load_4@plt>
  lea    0x1a(%rbx),%rdi
  mov    %eax,0x48(%rsp)
  call   <load_3@plt>
  lea    0x1c(%rbx),%rdi
  mov    %eax,0x4c(%rsp)
  call   <load_4@plt>
  mov    %r15,%rdi
  mov    %eax,0x50(%rsp)
  call   <load_3@plt>
  lea    0x2(%r15),%rdi
  mov    %eax,%ebp
  call   <load_4@plt>
  lea    0x5(%r15),%rdi
  and    $0x1fffff,%ebp
  mov    %eax,0x54(%rsp)
  call   <load_3@plt>
  lea    0x7(%r15),%rdi
  mov    %eax,0x58(%rsp)
  call   <load_4@plt>
  lea    0xa(%r15),%rdi
  mov    %eax,0x5c(%rsp)
  call   <load_4@plt>
  lea    0xd(%r15),%rdi
  mov    %eax,0x60(%rsp)
  call   <load_3@plt>
  lea    0xf(%r15),%rdi
  mov    %eax,0x64(%rsp)
  call   <load_4@plt>
  lea    0x12(%r15),%rdi
  mov    %eax,0x68(%rsp)
  call   <load_3@plt>
  lea    0x15(%r15),%rdi
  mov    %eax,0x6c(%rsp)
  call   <load_3@plt>
  lea    0x17(%r15),%rdi
  mov    %eax,%r14d
  call   <load_4@plt>
  lea    0x1a(%r15),%rdi
  mov    %eax,%r12d
  call   <load_3@plt>
  lea    0x1c(%r15),%rdi
  mov    %eax,%ebx
  call   <load_4@plt>
  mov    (%rsp),%r15d
  mov    0x54(%rsp),%edx
  mov    0x10(%rsp),%r10d
  mov    0x30(%rsp),%esi
  mov    %eax,%r9d
  lea    0x0(%r13,%rbp,1),%eax
  sar    $0x5,%r15d
  sar    $0x5,%edx
  mov    0x34(%rsp),%r11d
  mov    0x38(%rsp),%ecx
  and    $0x1fffff,%edx
  and    $0x1fffff,%r15d
  mov    0x3c(%rsp),%edi
  mov    0x40(%rsp),%ebp
  add    %edx,%r15d
  mov    0x58(%rsp),%edx
  sar    $0x2,%r10d
  mov    0x44(%rsp),%r13d
  and    $0x1fffff,%r10d
  sar    %ecx
  mov    0x48(%rsp),%r8d
  and    $0x1fffff,%r14d
  sar    $0x2,%edx
  sar    $0x7,%esi
  and    $0x1fffff,%ecx
  and    $0x1fffff,%r13d
  and    $0x1fffff,%edx
  and    $0x1fffff,%esi
  sar    $0x4,%r11d
  sar    $0x6,%edi
  add    %edx,%r10d
  mov    0x5c(%rsp),%edx
  sar    $0x3,%ebp
  and    $0x1fffff,%r11d
  and    $0x1fffff,%edi
  and    $0x1fffff,%ebp
  sar    $0x7,%edx
  and    $0x1fffff,%edx
  add    %edx,%esi
  mov    0x60(%rsp),%edx
  sar    $0x4,%edx
  and    $0x1fffff,%edx
  add    %edx,%r11d
  mov    0x64(%rsp),%edx
  sar    %edx
  and    $0x1fffff,%edx
  add    %edx,%ecx
  mov    0x68(%rsp),%edx
  sar    $0x6,%edx
  and    $0x1fffff,%edx
  add    %edx,%edi
  mov    0x6c(%rsp),%edx
  sar    $0x3,%edx
  and    $0x1fffff,%edx
  add    %edx,%ebp
  mov    0x4c(%rsp),%edx
  add    %r14d,%r13d
  mov    0x50(%rsp),%r14d
  sar    $0x2,%ebx
  sar    $0x5,%r8d
  sar    $0x2,%edx
  and    $0x1fffff,%ebx
  sar    $0x5,%r12d
  and    $0x1fffff,%r8d
  sar    $0x7,%r9d
  and    $0x1fffff,%edx
  and    $0x1fffff,%r12d
  sar    $0x7,%r14d
  add    %ebx,%edx
  lea    0x100000(%rax),%ebx
  add    %r12d,%r8d
  add    %r9d,%r14d
  lea    0x100000(%r10),%r12d
  mov    %ebx,%r9d
  and    $0xffe00000,%ebx
  sub    %ebx,%eax
  mov    %r12d,%ebx
  and    $0xffe00000,%r12d
  sar    $0x15,%r9d
  sub    %r12d,%r10d
  sar    $0x15,%ebx
  lea    0x100000(%r11),%r12d
  add    %r15d,%r9d
  add    %esi,%ebx
  mov    %r12d,%esi
  and    $0xffe00000,%r12d
  sub    %r12d,%r11d
  sar    $0x15,%esi
  lea    0x100000(%rdi),%r12d
  add    %ecx,%esi
  mov    %r12d,%ecx
  and    $0xffe00000,%r12d
  sar    $0x15,%ecx
  sub    %r12d,%edi
  add    %ebp,%ecx
  lea    0x100000(%r13),%ebp
  mov    %ebp,%r12d
  sar    $0x15,%r12d
  add    %r8d,%r12d
  and    $0xffe00000,%ebp
  lea    0x100000(%rdx),%r8d
  sub    %ebp,%r13d
  mov    %r8d,%ebp
  and    $0xffe00000,%r8d
  sar    $0x15,%ebp
  sub    %r8d,%edx
  add    %r14d,%ebp
  lea    0x100000(%r9),%r14d
  mov    %r14d,%r8d
  and    $0xffe00000,%r14d
  sub    %r14d,%r9d
  sar    $0x15,%r8d
  lea    0x100000(%rbx),%r14d
  add    %r10d,%r8d
  mov    %r14d,%r10d
  and    $0xffe00000,%r14d
  sar    $0x15,%r10d
  sub    %r14d,%ebx
  add    %r11d,%r10d
  lea    0x100000(%rsi),%r11d
  mov    %r11d,%r14d
  and    $0xffe00000,%r11d
  sub    %r11d,%esi
  sar    $0x15,%r14d
  lea    0x100000(%rcx),%r11d
  add    %edi,%r14d
  mov    %r11d,%edi
  and    $0xffe00000,%r11d
  sub    %r11d,%ecx
  sar    $0x15,%edi
  lea    0x100000(%r12),%r11d
  add    %r13d,%edi
  mov    %r11d,%r13d
  and    $0xffe00000,%r11d
  sub    %r11d,%r12d
  sar    $0x15,%r13d
  lea    0x100000(%rbp),%r11d
  add    %edx,%r13d
  mov    %r11d,%edx
  and    $0xffe00000,%r11d
  sar    $0x15,%edx
  sub    %r11d,%ebp
  imul   $0xa2c13,%edx,%r15d
  imul   $0x72d18,%edx,%r11d
  add    %eax,%r15d
  add    %r9d,%r11d
  imul   $0x215d1,%edx,%eax
  imul   $0x9fb67,%edx,%r9d
  add    %r10d,%eax
  mov    %r15d,%r10d
  and    $0x1fffff,%r15d
  sar    $0x15,%r10d
  add    %r8d,%r9d
  add    %r11d,%r10d
  imul   $0xfff0c653,%edx,%r8d
  mov    %r10d,%r11d
  imul   $0xfff59083,%edx,%edx
  and    $0x1fffff,%r10d
  sar    $0x15,%r11d
  add    %r9d,%r11d
  add    %ebx,%r8d
  mov    %r11d,%ebx
  add    %esi,%edx
  and    $0x1fffff,%r11d
  sar    $0x15,%ebx
  add    %r8d,%ebx
  mov    %ebx,%r9d
  and    $0x1fffff,%ebx
  sar    $0x15,%r9d
  add    %eax,%r9d
  mov    %r9d,%esi
  and    $0x1fffff,%r9d
  sar    $0x15,%esi
  add    %edx,%esi
  mov    %esi,%r8d
  and    $0x1fffff,%esi
  sar    $0x15,%r8d
  add    %r14d,%r8d
  mov    %r8d,%r14d
  and    $0x1fffff,%r8d
  sar    $0x15,%r14d
  add    %ecx,%r14d
  mov    %r14d,%ecx
  sar    $0x15,%ecx
  add    %edi,%ecx
  and    $0x1fffff,%r14d
  mov    %ecx,%eax
  and    $0x1fffff,%ecx
  sar    $0x15,%eax
  mov    %eax,%edi
  add    %r12d,%edi
  mov    %edi,%eax
  and    $0x1fffff,%edi
  sar    $0x15,%eax
  add    %eax,%r13d
  mov    %r13d,%r12d
  and    $0x1fffff,%r13d
  sar    $0x15,%r12d
  add    %ebp,%r12d
  mov    %r12d,%eax
  and    $0x1fffff,%r12d
  sar    $0x15,%eax
  imul   $0x72d18,%eax,%edx
  imul   $0xa2c13,%eax,%ebp
  add    %r10d,%edx
  imul   $0x9fb67,%eax,%r10d
  add    %r15d,%ebp
  add    %r11d,%r10d
  imul   $0xfff0c653,%eax,%r11d
  add    %ebx,%r11d
  imul   $0x215d1,%eax,%ebx
  imul   $0xfff59083,%eax,%eax
  add    %ebx,%r9d
  mov    %ebp,%ebx
  and    $0x1fffff,%ebp
  sar    $0x15,%ebx
  add    %esi,%eax
  mov    %ebp,%r15d
  add    %edx,%ebx
  mov    %ebx,%edx
  and    $0x1fffff,%ebx
  sar    $0x15,%edx
  add    %r10d,%edx
  mov    %edx,%r10d
  sar    $0x15,%r10d
  add    %r11d,%r10d
  and    $0x1fffff,%edx
  sar    $0x8,%r15d
  mov    %r10d,%r11d
  and    $0x1fffff,%r10d
  mov    %r15d,0x10(%rsp)
  mov    %ebx,%r15d
  sar    $0x15,%r11d
  sar    $0x3,%r15d
  add    %r9d,%r11d
  mov    %r11d,%r9d
  and    $0x1fffff,%r11d
  sar    $0x15,%r9d
  add    %eax,%r9d
  mov    %r9d,%esi
  and    $0x1fffff,%r9d
  sar    $0x15,%esi
  add    %r8d,%esi
  mov    %esi,%r8d
  and    $0x1fffff,%esi
  sar    $0x15,%r8d
  add    %r14d,%r8d
  mov    %r8d,%eax
  and    $0x1fffff,%r8d
  sar    $0x15,%eax
  add    %ecx,%eax
  mov    %eax,%ecx
  and    $0x1fffff,%eax
  sar    $0x15,%ecx
  mov    %eax,(%rsp)
  add    %edi,%ecx
  mov    %ecx,%edi
  and    $0x1fffff,%ecx
  sar    $0x15,%edi
  add    %r13d,%edi
  mov    %ebp,%r13d
  movzbl %bpl,%ebp
  mov    %edi,%eax
  sar    $0x10,%r13d
  and    $0x1fffff,%edi
  sar    $0x15,%eax
  mov    %r13d,%r14d
  lea    0x0(,%rdx,4),%r13d
  add    %r12d,%eax
  mov    %ebx,%r12d
  shl    $0x5,%r12d
  or     %r12d,%r14d
  mov    %ebx,%r12d
  sar    $0x13,%ebx
  mov    %r14b,0x30(%rsp)
  mov    %r10d,%r14d
  sar    $0xb,%r12d
  or     %r13d,%ebx
  shl    $0x7,%r14d
  mov    %edx,%r13d
  sar    $0xe,%edx
  movzbl %bl,%ebx
  or     %r14d,%edx
  mov    %r10d,%r14d
  sar    $0x6,%r13d
  movzbl %r12b,%r12d
  sar    %r14d
  mov    %dl,0x34(%rsp)
  mov    %esi,%edx
  movzbl %r13b,%r13d
  mov    %r14d,0x38(%rsp)
  mov    %r10d,%r14d
  sar    $0x11,%r10d
  sar    $0x9,%r14d
  shl    $0x6,%edx
  mov    %r14d,0x3c(%rsp)
  mov    %r11d,%r14d
  shl    $0x4,%r14d
  or     %r10d,%r14d
  mov    %r11d,%r10d
  sar    $0x4,%r10d
  mov    %r10d,0x40(%rsp)
  mov    %r11d,%r10d
  sar    $0x14,%r11d
  sar    $0xc,%r10d
  mov    %r10d,0x44(%rsp)
  lea    (%r9,%r9,1),%r10d
  or     %r10d,%r11d
  mov    %r9d,%r10d
  sar    $0xf,%r9d
  or     %edx,%r9d
  movzbl 0x34(%rsp),%edx
  sar    $0x7,%r10d
  movzbl %r11b,%r11d
  movzbl %r9b,%r9d
  movzbl %r10b,%r10d
  shl    $0x8,%rdx
  shl    $0x8,%r9
  or     %r13,%rdx
  mov    %esi,%r13d
  shl    $0x8,%rdx
  or     %rbx,%rdx
  movzbl %r15b,%ebx
  shl    $0x8,%rdx
  or     %r12,%rdx
  mov    %eax,%r12d
  shl    $0x8,%rdx
  or     %rbx,%rdx
  movzbl 0x30(%rsp),%ebx
  shl    $0x8,%rdx
  or     %rbx,%rdx
  movzbl 0x10(%rsp),%ebx
  shl    $0x8,%rdx
  or     %rbx,%rdx
  shl    $0x8,%rdx
  or     %r10,%r9
  movzbl 0x44(%rsp),%r10d
  sar    $0xa,%r13d
  shl    $0x8,%r9
  or     %rbp,%rdx
  mov    %eax,%ebp
  or     %r11,%r9
  mov    %ecx,%r11d
  shl    $0x7,%ebp
  shl    $0x8,%r9
  sar    $0xb,%r11d
  or     %r10,%r9
  movzbl 0x40(%rsp),%r10d
  shl    $0x8,%r9
  or     %r10,%r9
  movzbl %r14b,%r10d
  mov    %r8d,%r14d
  shl    $0x8,%r9
  sar    $0x5,%r14d
  or     %r10,%r9
  movzbl 0x3c(%rsp),%r10d
  movzbl %r14b,%r14d
  shl    $0x8,%r9
  or     %r10,%r9
  movzbl 0x38(%rsp),%r10d
  mov    %rdx,0x10(%rsp)
  shl    $0x8,%r9
  mov    0x28(%rsp),%rdx
  mov    (%rsp),%ebx
  or     %r10,%r9
  mov    %esi,%r10d
  sar    $0x12,%esi
  mov    %r9,0x18(%rsp)
  mov    %ecx,%r9d
  mov    %ebx,%r15d
  sar    $0x2,%r10d
  movdqa 0x10(%rsp),%xmm0
  shl    $0x5,%r9d
  sar    $0x8,%r15d
  movzbl %r10b,%r10d
  movzbl %r15b,%r15d
  movups %xmm0,(%rdx)
  lea    0x0(,%r8,8),%edx
  sar    $0xd,%r8d
  or     %edx,%esi
  mov    %ebx,%edx
  lea    0x0(,%rdi,4),%ebx
  movzbl %r8b,%r8d
  sar    $0x10,%edx
  or     %r9d,%edx
  mov    %ecx,%r9d
  sar    $0x13,%ecx
  or     %ebx,%ecx
  mov    %edi,%ebx
  sar    $0xe,%edi
  movzbl %dl,%edx
  sar    $0x6,%ebx
  or     %ebp,%edi
  mov    %eax,%ebp
  sar    $0x3,%r9d
  sar    %ebp
  shl    $0x8,%rdx
  movzbl %r9b,%r9d
  sar    $0x11,%eax
  or     %r15,%rdx
  movzbl (%rsp),%r15d
  sar    $0x9,%r12d
  shl    $0x8,%rdx
  movzbl %al,%eax
  movzbl %r12b,%r12d
  or     %r15,%rdx
  shl    $0x8,%rax
  shl    $0x8,%rdx
  or     %r12,%rax
  or     %r8,%rdx
  movzbl %sil,%r8d
  shl    $0x8,%rax
  shl    $0x8,%rdx
  or     %r14,%rdx
  mov    %rdx,%rsi
  movzbl %r13b,%edx
  shl    $0x8,%rsi
  or     %r8,%rsi
  shl    $0x8,%rsi
  mov    %rsi,%r13
  or     %rdx,%r13
  movzbl %bpl,%edx
  mov    %rax,%rbp
  movzbl %dil,%eax
  or     %rdx,%rbp
  shl    $0x8,%r13
  mov    0x28(%rsp),%rdx
  mov    %rbp,%rdi
  or     %r10,%r13
  shl    $0x8,%rdi
  mov    %r13,(%rsp)
  or     %rax,%rdi
  movzbl %bl,%eax
  mov    %rdi,%rbx
  shl    $0x8,%rbx
  or     %rax,%rbx
  movzbl %cl,%eax
  mov    %rbx,%rcx
  shl    $0x8,%rcx
  or     %rax,%rcx
  movzbl %r11b,%eax
  shl    $0x8,%rcx
  mov    %rcx,%r11
  or     %rax,%r11
  shl    $0x8,%r11
  or     %r9,%r11
  mov    %r11,0x8(%rsp)
  movdqa (%rsp),%xmm1
  movups %xmm1,0x10(%rdx)
  add    $0x78,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
```

assistant: ```c
void sc_add(unsigned char *s, const unsigned char *a, const unsigned char *b) {
  int64_t a0 = 2097151 & load_3(a);
  int64_t a1 = 2097151 & (load_4(a + 2) >> 5);
  int64_t a2 = 2097151 & (load_3(a + 5) >> 2);
  int64_t a3 = 2097151 & (load_4(a + 7) >> 7);
  int64_t a4 = 2097151 & (load_4(a + 10) >> 4);
  int64_t a5 = 2097151 & (load_3(a + 13) >> 1);
  int64_t a6 = 2097151 & (load_4(a + 15) >> 6);
  int64_t a7 = 2097151 & (load_3(a + 18) >> 3);
  int64_t a8 = 2097151 & load_3(a + 21);
  int64_t a9 = 2097151 & (load_4(a + 23) >> 5);
  int64_t a10 = 2097151 & (load_3(a + 26) >> 2);
  int64_t a11 = (load_4(a + 28) >> 7);
  int64_t b0 = 2097151 & load_3(b);
  int64_t b1 = 2097151 & (load_4(b + 2) >> 5);
  int64_t b2 = 2097151 & (load_3(b + 5) >> 2);
  int64_t b3 = 2097151 & (load_4(b + 7) >> 7);
  int64_t b4 = 2097151 & (load_4(b + 10) >> 4);
  int64_t b5 = 2097151 & (load_3(b + 13) >> 1);
  int64_t b6 = 2097151 & (load_4(b + 15) >> 6);
  int64_t b7 = 2097151 & (load_3(b + 18) >> 3);
  int64_t b8 = 2097151 & load_3(b + 21);
  int64_t b9 = 2097151 & (load_4(b + 23) >> 5);
  int64_t b10 = 2097151 & (load_3(b + 26) >> 2);
  int64_t b11 = (load_4(b + 28) >> 7);
  int64_t s0 = a0 + b0;
  int64_t s1 = a1 + b1;
  int64_t s2 = a2 + b2;
  int64_t s3 = a3 + b3;
  int64_t s4 = a4 + b4;
  int64_t s5 = a5 + b5;
  int64_t s6 = a6 + b6;
  int64_t s7 = a7 + b7;
  int64_t s8 = a8 + b8;
  int64_t s9 = a9 + b9;
  int64_t s10 = a10 + b10;
  int64_t s11 = a11 + b11;
  int64_t s12 = 0;
  int64_t carry0;
  int64_t carry1;
  int64_t carry2;
  int64_t carry3;
  int64_t carry4;
  int64_t carry5;
  int64_t carry6;
  int64_t carry7;
  int64_t carry8;
  int64_t carry9;
  int64_t carry10;
  int64_t carry11;
  carry0 = (s0 + (1 << 20)) >> 21;
  s1 += carry0;
  s0 -= carry0 << 21;
  carry2 = (s2 + (1 << 20)) >> 21;
  s3 += carry2;
  s2 -= carry2 << 21;
  carry4 = (s4 + (1 << 20)) >> 21;
  s5 += carry4;
  s4 -= carry4 << 21;
  carry6 = (s6 + (1 << 20)) >> 21;
  s7 += carry6;
  s6 -= carry6 << 21;
  carry8 = (s8 + (1 << 20)) >> 21;
  s9 += carry8;
  s8 -= carry8 << 21;
  carry10 = (s10 + (1 << 20)) >> 21;
  s11 += carry10;
  s10 -= carry10 << 21;
  carry1 = (s1 + (1 << 20)) >> 21;
  s2 += carry1;
  s1 -= carry1 << 21;
  carry3 = (s3 + (1 << 20)) >> 21;
  s4 += carry3;
  s3 -= carry3 << 21;
  carry5 = (s5 + (1 << 20)) >> 21;
  s6 += carry5;
  s5 -= carry5 << 21;
  carry7 = (s7 + (1 << 20)) >> 21;
  s8 += carry7;
  s7 -= carry7 << 21;
  carry9 = (s9 + (1 << 20)) >> 21;
  s10 += carry9;
  s9 -= carry9 << 21;
  carry11 = (s11 + (1 << 20)) >> 21;
  s12 += carry11;
  s11 -= carry11 << 21;
  s0 += s12 * 666643;
  s1 += s12 * 470296;
  s2 += s12 * 654183;
  s3 -= s12 * 997805;
  s4 += s12 * 136657;
  s5 -= s12 * 683901;
  s12 = 0;
  carry0 = s0 >> 21;
  s1 += carry0;
  s0 -= carry0 << 21;
  carry1 = s1 >> 21;
  s2 += carry1;
  s1 -= carry1 << 21;
  carry2 = s2 >> 21;
  s3 += carry2;
  s2 -= carry2 << 21;
  carry3 = s3 >> 21;
  s4 += carry3;
  s3 -= carry3 << 21;
  carry4 = s4 >> 21;
  s5 += carry4;
  s4 -= carry4 << 21;
  carry5 = s5 >> 21;
  s6 += carry5;
  s5 -= carry5 << 21;
  carry6 = s6 >> 21;
  s7 += carry6;
  s6 -= carry6 << 21;
  carry7 = s7 >> 21;
  s8 += carry7;
  s7 -= carry7 << 21;
  carry8 = s8 >> 21;
  s9 += carry8;
  s8 -= carry8 << 21;
  carry9 = s9 >> 21;
  s10 += carry9;
  s9 -= carry9 << 21;
  carry10 = s10 >> 21;
  s11 += carry10;
  s10 -= carry10 << 21;
  carry11 = s11 >> 21;
  s12 += carry11;
  s11 -= carry11 << 21;
  s0 += s12 * 666643;
  s1 += s12 * 470296;
  s2 += s12 * 654183;
  s3 -= s12 * 997805;
  s4 += s12 * 136657;
  s5 -= s12 * 683901;
  carry0 = s0 >> 21;
  s1 += carry0;
  s0 -= carry0 << 21;
  carry1 = s1 >> 21;
  s2 += carry1;
  s1 -= carry1 << 21;
  carry2 = s2 >> 21;
  s3 += carry2;
  s2 -= carry2 << 21;
  carry3 = s3 >> 21;
  s4 += carry3;
  s3 -= carry3 << 21;
  carry4 = s4 >> 21;
  s5 += carry4;
  s4 -= carry4 << 21;
  carry5 = s5 >> 21;
  s6 += carry5;
  s5 -= carry5 << 21;
  carry6 = s6 >> 21;
  s7 += carry6;
  s6 -= carry6 << 21;
  carry7 = s7 >> 21;
  s8 += carry7;
  s7 -= carry7 << 21;
  carry8 = s8 >> 21;
  s9 += carry8;
  s8 -= carry8 << 21;
  carry9 = s9 >> 21;
  s10 += carry9;
  s9 -= carry9 << 21;
  carry10 = s10 >> 21;
  s11 += carry10;
  s10 -= carry10 << 21;
  s[0] = (unsigned char)(s0 >> 0);
  s[1] = (unsigned char)(s0 >> 8);
  s[2] = (unsigned char)((s0 >> 16) | (s1 << 5));
  s[3] = (unsigned char)(s1 >> 3);
  s[4] = (unsigned char)(s1 >> 11);
  s[5] = (unsigned char)((s1 >> 19) | (s2 << 2));
  s[6] = (unsigned char)(s2 >> 6);
  s[7] = (unsigned char)((s2 >> 14) | (s3 << 7));
  s[8] = (unsigned char)(s3 >> 1);
  s[9] = (unsigned char)(s3 >> 9);
  s[10] = (unsigned char)((s3 >> 17) | (s4 << 4));
  s[11] = (unsigned char)(s4 >> 4);
  s[12] = (unsigned char)(s4 >> 12);
  s[13] = (unsigned char)((s4 >> 20) | (s5 << 1));
  s[14] = (unsigned char)(s5 >> 7);
  s[15] = (unsigned char)((s5 >> 15) | (s6 << 6));
  s[16] = (unsigned char)(s6 >> 2);
  s[17] = (unsigned char)(s6 >> 10);
  s[18] = (unsigned char)((s6 >> 18) | (s7 << 3));
  s[19] = (unsigned char)(s7 >> 5);
  s[20] = (unsigned char)(s7 >> 13);
  s[21] = (unsigned char)(s8 >> 0);
  s[22] = (unsigned char)(s8 >> 8);
  s[23] = (unsigned char)((s8 >> 16) | (s9 << 5));
  s[24] = (unsigned char)(s9 >> 3);
  s[25] = (unsigned char)(s9 >> 11);
  s[26] = (unsigned char)((s9 >> 19) | (s10 << 2));
  s[27] = (unsigned char)(s10 >> 6);
  s[28] = (unsigned char)((s10 >> 14) | (s11 << 7));
  s[29] = (unsigned char)(s11 >> 1);
  s[30] = (unsigned char)(s11 >> 9);
  s[31] = (unsigned char)(s11 >> 17);
}
```