user: What is the c source code of the assembly code below:

```asm
<copy_smatrix>:
  endbr64
  push   %r15
  mov    %rdi,%r11
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  mov    0x38(%rsp),%ebx
  mov    0x48(%rsp),%r12d
  sub    %esi,%ebx
  movslq %esi,%rsi
  mov    %rdx,-0x58(%rsp)
  sub    %ecx,%r12d
  cmp    %rsi,%rdx
  jl     L46
  movslq %ebx,%rdx
  movslq %ecx,%rbx
  mov    %ecx,-0xc(%rsp)
  mov    %rcx,%rax
  cmp    %rbx,%r8
  jl     L46
  lea    (%r9,%rdx,8),%rdx
  mov    %r8,%rbp
  lea    (%rbx,%rbx,1),%rdi
  mov    %rdx,-0x40(%rsp)
  movslq %r12d,%rdx
  sub    %rbx,%rbp
  lea    (%rdx,%rbx,1),%r14
  mov    %rdi,-0x30(%rsp)
  lea    (%r14,%r14,1),%rcx
  mov    %rcx,-0x48(%rsp)
  lea    0x2(%rbx,%rbx,1),%rcx
  mov    %rcx,-0x50(%rsp)
  lea    0x1(%rbp),%rcx
  mov    %rcx,%r9
  mov    %rcx,-0x38(%rsp)
  and    $0xfffffffffffffff8,%rcx
  add    %ecx,%eax
  shr    $0x3,%r9
  mov    %rcx,%r13
  mov    %eax,-0x10(%rsp)
  lea    (%rdx,%rdx,1),%rax
  shl    $0x4,%r9
  mov    %rax,-0x18(%rsp)
  mov    %rbp,%rax
  sub    %rcx,%rax
  mov    %rax,-0x28(%rsp)
  add    $0x1,%rax
  mov    %rax,-0x20(%rsp)
  cs nopw 0x0(%rax,%rax,1)
L40:
  mov    -0x40(%rsp),%rax
  mov    (%r11,%rsi,8),%rdx
  mov    (%rax,%rsi,8),%rcx
  mov    -0x48(%rsp),%rax
  lea    (%rcx,%rax,1),%rdi
  mov    -0x50(%rsp),%rax
  lea    (%rdx,%rax,1),%r10
  mov    %rdi,%rax
  sub    %r10,%rax
  cmp    $0xc,%rax
  jbe    L42
  cmp    $0x2,%rbp
  jbe    L42
  cmp    $0x6,%rbp
  jbe    L123
  mov    -0x30(%rsp),%rax
  lea    (%rdx,%rax,1),%r10
  xor    %eax,%eax
  xchg   %ax,%ax
L17:
  movdqu (%r10,%rax,1),%xmm0
  movups %xmm0,(%rdi,%rax,1)
  add    $0x10,%rax
  cmp    %r9,%rax
  jne    L17
  cmp    %r13,-0x38(%rsp)
  je     L106
  cmpq   $0x2,-0x28(%rsp)
  mov    -0x20(%rsp),%r10
  jbe    L100
  mov    -0x10(%rsp),%eax
  mov    %r13,%rdi
L0:
  lea    (%rbx,%rdi,1),%r15
  add    %r14,%rdi
  mov    (%rdx,%r15,2),%r15
  mov    %r15,(%rcx,%rdi,2)
  mov    %r10,%rdi
  and    $0xfffffffffffffffc,%rdi
  add    %edi,%eax
  cmp    %rdi,%r10
  je     L106
L165:
  movslq %eax,%rdi
  movzwl (%rdx,%rdi,2),%r15d
  lea    (%rdi,%rdi,1),%r10
  lea    (%r12,%rax,1),%edi
  movslq %edi,%rdi
  mov    %r15w,(%rcx,%rdi,2)
  lea    0x1(%rax),%edi
  movslq %edi,%r15
  cmp    %r15,%r8
  jl     L106
  movzwl 0x2(%rdx,%r10,1),%r15d
  add    %r12d,%edi
  add    $0x2,%eax
  movslq %edi,%rdi
  mov    %r15w,(%rcx,%rdi,2)
  movslq %eax,%rdi
  cmp    %rdi,%r8
  jl     L106
  movzwl 0x4(%rdx,%r10,1),%edx
  add    %r12d,%eax
  cltq
  mov    %dx,(%rcx,%rax,2)
L106:
  lea    0x1(%rsi),%rax
  cmp    -0x58(%rsp),%rsi
  je     L46
L153:
  mov    %rax,%rsi
  jmp    L40
  nopl   0x0(%rax)
L42:
  add    -0x18(%rsp),%rcx
  mov    %rbx,%rax
L67:
  movzwl (%rdx,%rax,2),%edi
  mov    %di,(%rcx,%rax,2)
  mov    %rax,%rdi
  add    $0x1,%rax
  cmp    %r8,%rdi
  jne    L67
  lea    0x1(%rsi),%rax
  cmp    -0x58(%rsp),%rsi
  jne    L153
L46:
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L123:
  mov    -0x38(%rsp),%r10
  mov    -0xc(%rsp),%eax
  xor    %edi,%edi
  jmp    L0
L100:
  mov    -0x10(%rsp),%eax
  jmp    L165
```

assistant: ```c
void copy_smatrix(short **m1, long nrl1, long nrh1, long ncl1, long nch1, short **m2, long nrl2, long nrh2, long ncl2, long nch2) {
  int i, j, ro, co;
  ro = nrl2 - nrl1;
  co = ncl2 - ncl1;
  for (i = nrl1; i <= nrh1; i++) {
    for (j = ncl1; j <= nch1; j++) {
      m2[i + ro][j + co] = m1[i][j];
    }
  }
}
```