user: 下面的汇编指令对应的C源代码是什么：

```asm
<Decompress420HiNoMMX>:
  endbr64
  push   %r15
  imul   %edx,%ecx
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  mov    %rdi,%rbp
  push   %rbx
  sub    $0x68,%rsp
  mov    %fs:0x28,%rax
  mov    %rax,0x58(%rsp)
  xor    %eax,%eax
  movslq %ecx,%rax
  test   %ecx,%ecx
  movl   $0x0,0x54(%rsp)
  lea    (%rsi,%rax,1),%rdi
  lea    0x3(%rcx),%eax
  movl   $0x0,0x50(%rsp)
  cmovns %ecx,%eax
  mov    %rdi,0x10(%rsp)
  movl   $0x0,0x4c(%rsp)
  sar    $0x2,%eax
  movl   $0x0,0x48(%rsp)
  cltq
  add    %rdi,%rax
  test   %ecx,%ecx
  mov    %rax,0x18(%rsp)
  lea    0xff(%rcx),%eax
  cmovns %ecx,%eax
  sar    $0x8,%eax
  mov    %eax,0x24(%rsp)
  cmp    $0xff,%ecx
  jle    L16
  mov    %edx,%eax
  mov    %rsi,%r13
  movl   $0x0,0xc(%rsp)
  mov    %edx,%ebx
  shr    $0x1f,%eax
  lea    0x54(%rsp),%r12
  lea    0x48(%rsp),%r14
  xor    %r15d,%r15d
  add    %edx,%eax
  movl   $0x0,0x8(%rsp)
  sar    %eax
  mov    %eax,0x20(%rsp)
  lea    0x0(,%rdx,8),%eax
  sub    %edx,%eax
  mov    %eax,%esi
  mov    %eax,0x38(%rsp)
  shr    $0x1f,%eax
  add    %esi,%eax
  sar    %eax
  mov    %eax,0x3c(%rsp)
  lea    0x4c(%rsp),%rax
  mov    %rax,0x30(%rsp)
  lea    0x50(%rsp),%rax
  mov    %rax,0x28(%rsp)
  nopl   0x0(%rax)
L5:
  mov    0x20(%rsp),%r8d
  mov    0x30(%rsp),%rcx
  mov    %r12,%rdx
  mov    %rbp,%rdi
  mov    0x10(%rsp),%rsi
  mov    $0x2,%r9d
  call   <DecompressYHI@plt>
  mov    0x20(%rsp),%r8d
  mov    %r12,%rdx
  mov    %rbp,%rdi
  mov    0x28(%rsp),%rcx
  mov    0x18(%rsp),%rsi
  mov    $0x2,%r9d
  call   <DecompressYHI@plt>
  addl   $0x10,0x8(%rsp)
  mov    0x8(%rsp),%eax
  cmp    %eax,%ebx
  jg     L28
  mov    0x3c(%rsp),%eax
  add    %eax,0x4c(%rsp)
  add    %eax,0x50(%rsp)
  movl   $0x0,0x8(%rsp)
L28:
  mov    $0x1,%r9d
  mov    %ebx,%r8d
  mov    %r14,%rcx
  mov    %r12,%rdx
  mov    %r13,%rsi
  mov    %rbp,%rdi
  call   <DecompressYHI@plt>
  mov    %ebx,%r8d
  mov    %r14,%rcx
  mov    %r12,%rdx
  mov    $0x1,%r9d
  mov    %r13,%rsi
  mov    %rbp,%rdi
  call   <DecompressYHI@plt>
  lea    0x10(%r15),%eax
  add    $0x20,%r15d
  cmp    %eax,%ebx
  jg     L56
  mov    0x38(%rsp),%eax
  add    %eax,0x48(%rsp)
  mov    $0x10,%r15d
L56:
  mov    $0x1,%r9d
  mov    %ebx,%r8d
  mov    %r14,%rcx
  mov    %r12,%rdx
  mov    %r13,%rsi
  mov    %rbp,%rdi
  call   <DecompressYHI@plt>
  mov    %ebx,%r8d
  mov    %r14,%rcx
  mov    %r12,%rdx
  mov    $0x1,%r9d
  mov    %r13,%rsi
  mov    %rbp,%rdi
  call   <DecompressYHI@plt>
  cmp    %r15d,%ebx
  jg     L3
  mov    0x38(%rsp),%eax
  add    %eax,0x48(%rsp)
  xor    %r15d,%r15d
L3:
  addl   $0x1,0xc(%rsp)
  mov    0xc(%rsp),%eax
  cmp    %eax,0x24(%rsp)
  jg     L5
L16:
  mov    0x58(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L59
  add    $0x68,%rsp
  xor    %eax,%eax
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L59:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
int Decompress420HiNoMMX(unsigned char *pIn, unsigned char *pOut, const int w, const int h, const int inSize) {
  unsigned char *pY = pOut;
  unsigned char *pU = pY + w * h;
  unsigned char *pV = pU + w * h / 4;
  int xY, xUV, iY, iU, iV, iIn, count;
  const int nBlocks = (w * h) / (32 * 8);
  iIn = 0;
  iY = iU = iV = 0;
  xY = xUV = 0;
  for (count = 0; count < nBlocks; count++) {
    DecompressYHI(pIn, pU, &iIn, &iU, w / 2, 2);
    DecompressYHI(pIn, pV, &iIn, &iV, w / 2, 2);
    xUV += 16;
    if (xUV >= w) {
      iU += (w * 7) / 2;
      iV += (w * 7) / 2;
      xUV = 0;
    }
    DecompressYHI(pIn, pY, &iIn, &iY, w, 1);
    xY += 8;
    DecompressYHI(pIn, pY, &iIn, &iY, w, 1);
    xY += 8;
    if (xY >= w) {
      iY += w * 7;
      xY = 0;
    }
    DecompressYHI(pIn, pY, &iIn, &iY, w, 1);
    xY += 8;
    DecompressYHI(pIn, pY, &iIn, &iY, w, 1);
    xY += 8;
    if (xY >= w) {
      iY += w * 7;
      xY = 0;
    }
  }
  return 0;
}
```