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

```asm
<pdef>:
  endbr64
  movapd %xmm0,%xmm3
  movsd  0xa8(%rdi),%xmm0
  pxor   %xmm2,%xmm2
  xor    %eax,%eax
  comisd %xmm0,%xmm2
  jae    L58
  push   %r15
  mov    %edx,%r15d
  push   %r14
  mov    %rdi,%r14
  push   %r13
  mov    %rsi,%r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x28,%rsp
  ucomisd %xmm0,%xmm2
  ja     L158
  sqrtsd %xmm0,%xmm0
L19:
  movsd  %xmm0,0xa8(%r13)
  cmp    $0x1,%r15d
  jle    L18
  lea    0x140(%r13),%r9
  mov    $0x150,%r12d
  movq   D16(%rip),%xmm4
  mov    $0x2,%ebp
  mov    %r9,%rbx
  lea    0xa8(%r13),%r10
  nopl   0x0(%rax)
L145:
  lea    0x0(%rbp,%rbp,4),%rdi
  movslq %ebp,%r8
  mov    %r10,%rsi
  mov    %r9,%rcx
  shl    $0x5,%rdi
  mov    $0x2,%edx
  movapd %xmm2,%xmm1
  add    %r14,%rdi
  xchg   %ax,%ax
L85:
  movsd  -0x8(%rdi,%rdx,8),%xmm0
  subsd  %xmm1,%xmm0
  movapd %xmm0,%xmm1
  andpd  %xmm4,%xmm1
  comisd %xmm3,%xmm1
  jbe    L63
  divsd  (%rsi),%xmm0
L0:
  movsd  %xmm0,-0x8(%rbx,%rdx,8)
  movq   $0x0,-0xa0(%rcx,%rbp,8)
  cmp    %rbp,%rdx
  je     L62
  cmp    $0x1,%edx
  jle    L57
  mov    $0x1,%eax
  movapd %xmm2,%xmm1
  nopl   (%rax)
L131:
  movsd  (%rcx,%rax,8),%xmm0
  mulsd  (%rbx,%rax,8),%xmm0
  add    $0x1,%rax
  addsd  %xmm0,%xmm1
  cmp    %rax,%rdx
  jne    L131
L29:
  add    $0x1,%rdx
  add    $0xa8,%rsi
  add    $0xa0,%rcx
  jmp    L85
  nopl   0x0(%rax,%rax,1)
L63:
  movapd %xmm2,%xmm0
  jmp    L0
  xchg   %ax,%ax
L62:
  lea    0x8(%rbx),%rax
  movapd %xmm2,%xmm1
  lea    0x0(%r13,%r12,1),%rdx
  nopl   (%rax)
L53:
  movsd  (%rax),%xmm0
  add    $0x8,%rax
  mulsd  %xmm0,%xmm0
  addsd  %xmm0,%xmm1
  cmp    %rdx,%rax
  jne    L53
  movsd  (%r14,%r12,1),%xmm0
  subsd  %xmm1,%xmm0
  comisd %xmm0,%xmm2
  jae    L71
  ucomisd %xmm0,%xmm2
  ja     L118
  sqrtsd %xmm0,%xmm0
L153:
  add    $0x1,%rbp
  movsd  %xmm0,0x0(%r13,%r12,1)
  add    $0xa0,%rbx
  add    $0xa8,%r12
  cmp    %ebp,%r15d
  jge    L145
L18:
  add    $0x28,%rsp
  mov    $0x1,%eax
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L58:
  ret
L71:
  movq   $0x0,(%rbx,%r8,8)
  add    $0x28,%rsp
  xor    %eax,%eax
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L57:
  movapd %xmm2,%xmm1
  jmp    L29
L158:
  movsd  %xmm3,0x8(%rsp)
  call   <sqrt@plt>
  movsd  0x8(%rsp),%xmm3
  pxor   %xmm2,%xmm2
  jmp    L19
L118:
  mov    %r10,0x18(%rsp)
  mov    %r9,0x8(%rsp)
  movsd  %xmm3,0x10(%rsp)
  call   <sqrt@plt>
  mov    0x18(%rsp),%r10
  movsd  0x10(%rsp),%xmm3
  pxor   %xmm2,%xmm2
  movq   D16(%rip),%xmm4
  mov    0x8(%rsp),%r9
  jmp    L153
```

tool_calls: name: extract_symbolic_data
arguments: label: D16
type: qword

tool: D16: 9223372036854775807

assistant: ```c
int pdef(double a[][20], double l[][20], int n, double toler) {
  int i, j, k;
  double sum;
  if (a[1][1] <= 0) {
    return 0;
  } else
    l[1][1] = sqrt(a[1][1]);
  for (k = 2; k <= n; k++) {
    for (i = 1; i < k; i++) {
      sum = 0.;
      for (j = 1; j < i; j++)
        sum += l[i][j] * l[k][j];
      if (fabs(a[k][i] - sum) > toler) {
        l[k][i] = (a[k][i] - sum) / l[i][i];
      } else
        l[k][i] = 0.;
      l[i][k] = 0.;
    }
    for (j = 1, sum = 0.; j < k; j++)
      sum += l[k][j] * l[k][j];
    if (a[k][k] - sum <= 0.) {
      l[k][k] = 0.;
      return 0;
    } else
      l[k][k] = sqrt(a[k][k] - sum);
  }
  return 1;
}
```