user: 请显示与下面列出的汇编代码相匹配的C语言实现:

```asm
<dtrans_mat_mat_mult>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  mov    %rdi,-0x8(%rsp)
  mov    %rsi,-0x50(%rsp)
  mov    %edx,-0x30(%rsp)
  mov    %ecx,-0x2c(%rsp)
  test   %ecx,%ecx
  jle    L71
  mov    -0x2c(%rsp),%ebx
  lea    -0x1(%rbx),%eax
  and    $0xffffffe0,%eax
  add    $0x40,%eax
  mov    %eax,-0xc(%rsp)
  movslq %ebx,%rax
  lea    0x0(,%rax,8),%r15
  shl    $0x5,%ebx
  mov    %ebx,%eax
  cltq
  shl    $0x3,%rax
  mov    %rax,-0x18(%rsp)
  movl   $0x1f,-0x20(%rsp)
  movl   $0x20,-0x34(%rsp)
  jmp    L46
L200:
  movq   $0x0,(%rdx,%rax,8)
  add    $0x1,%rax
L160:
  cmp    %eax,%ecx
  jg     L200
  lea    0x1(%rdi),%eax
  add    %r15,%rdx
  cmp    %eax,-0x2c(%rsp)
  je     L58
  mov    %eax,%edi
L188:
  cmp    %r14d,%edi
  mov    %r14d,%eax
  cmovge %edi,%eax
  cltq
  jmp    L160
L58:
  mov    %eax,-0x1c(%rsp)
  mov    %edi,-0x10(%rsp)
  cmpl   $0x0,-0x30(%rsp)
  jle    L10
  cmp    %eax,%esi
  cmovge %eax,%ebx
  movq   $0x0,-0x28(%rsp)
  mov    $0x0,%ebp
  cltq
  mov    %rax,-0x48(%rsp)
  mov    %edi,%eax
  mov    %rax,-0x40(%rsp)
  jmp    L64
L123:
  mov    %rax,%rdi
  sub    %r8,%rdi
  movsd  (%rdi,%rcx,1),%xmm0
  mulsd  (%rax),%xmm0
  addsd  %xmm0,%xmm1
  add    $0x1,%edx
  add    %r15,%rax
L187:
  cmp    %esi,%edx
  jl     L123
  addsd  (%r10,%r9,8),%xmm1
  movsd  %xmm1,(%r10,%r9,8)
  add    $0x1,%r9
L9:
  cmp    %r9d,%ebx
  jle    L197
  lea    0x0(,%r9,8),%rcx
  mov    %r11,%rax
  mov    %ebp,%edx
  pxor   %xmm1,%xmm1
  jmp    L187
L197:
  lea    0x1(%r12),%rax
  add    -0x48(%rsp),%r13
  add    $0x8,%r11
  cmp    -0x40(%rsp),%r12
  je     L121
  mov    %rax,%r12
L152:
  lea    0x0(,%r12,8),%r8
  mov    %r12d,%eax
  cmp    %r12d,%r14d
  cmovge %r14d,%eax
  movslq %eax,%r9
  mov    -0x50(%rsp),%rax
  lea    (%rax,%r13,8),%r10
  jmp    L9
L121:
  add    $0x20,%ebp
  mov    -0x18(%rsp),%rcx
  add    %rcx,-0x28(%rsp)
  cmp    %ebp,-0x30(%rsp)
  jle    L10
L64:
  lea    0x20(%rbp),%esi
  lea    0x1f(%rbp),%eax
  mov    -0x30(%rsp),%ecx
  cmp    %eax,%ecx
  cmovle %ecx,%esi
  mov    -0x8(%rsp),%r11
  add    -0x28(%rsp),%r11
  mov    $0x0,%r13d
  mov    $0x0,%r12d
  jmp    L152
L10:
  addl   $0x20,-0x34(%rsp)
  mov    -0x34(%rsp),%eax
  addl   $0x20,-0x20(%rsp)
  cmp    -0xc(%rsp),%eax
  je     L109
L46:
  mov    -0x34(%rsp),%ecx
  lea    -0x20(%rcx),%r14d
  mov    -0x20(%rsp),%eax
  mov    %eax,%esi
  mov    %ecx,%ebx
  mov    -0x2c(%rsp),%edx
  cmp    %edx,%eax
  cmovge %edx,%ecx
  mov    -0x50(%rsp),%rdx
  mov    $0x0,%edi
  jmp    L188
L109:
  mov    -0x50(%rsp),%rbx
  mov    %rbx,%rsi
  mov    $0x0,%ecx
  mov    $0x0,%eax
  lea    0x8(%rbx),%r9
  jmp    L96
L80:
  movslq %ecx,%r8
  mov    -0x50(%rsp),%rbx
  lea    (%rbx,%r8,8),%rdx
  mov    %eax,%eax
  add    %r8,%rax
  lea    (%r9,%rax,8),%r8
  mov    %rsi,%rax
L179:
  movsd  (%rax),%xmm0
  movsd  %xmm0,(%rdx)
  add    %r15,%rax
  add    $0x8,%rdx
  cmp    %r8,%rdx
  jne    L179
L191:
  mov    %edi,%eax
L96:
  lea    0x1(%rax),%edi
  add    $0x8,%rsi
  add    -0x1c(%rsp),%ecx
  cmp    -0x10(%rsp),%eax
  je     L71
  test   %edi,%edi
  jg     L80
  jmp    L191
L71:
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
```

assistant: ```c
void dtrans_mat_mat_mult(double *a, double *b, int n, int m) {
  register int i, j, k, jj, kk;
  register double sum, *bim, *akm;
  const int bsize = 32;
  for (jj = 0; jj < m; jj += bsize) {
    for (i = 0; i < m; ++i) {
      bim = b + i * m;
      for (j = (((jj) >= (i)) ? (jj) : (i)); j < (((jj + bsize) <= (m)) ? (jj + bsize) : (m)); ++j)
        bim[j] = 0.0;
    }
    for (kk = 0; kk < n; kk += bsize) {
      for (i = 0; i < m; ++i) {
        bim = b + i * m;
        for (j = (((jj) >= (i)) ? (jj) : (i)); j < (((jj + bsize) <= (m)) ? (jj + bsize) : (m)); ++j) {
          sum = 0.0;
          for (k = kk; k < (((kk + bsize) <= (n)) ? (kk + bsize) : (n)); ++k) {
            akm = a + k * m;
            sum += akm[i] * akm[j];
          }
          bim[j] += sum;
        }
      }
    }
  }
  for (i = 0; i < m; ++i)
    for (j = 0; j < i; ++j)
      b[i * m + j] = b[j * m + i];
}
```