void dt2tai(date, time) double *date;
double *time;
{
  double dj, dt, tsec;
  dj = dt2jd(*date, *time);
  dt = utdt(dj);
  tsec = dt2ts(*date, *time);
  tsec = tsec + dt - 32.184;
  ts2dt(tsec, date, time);
  return;
}


x86 assembly (clang, -O0):
<dt2tai>:
push   %rbp
mov    %rsp,%rbp
sub    $0x30,%rsp
mov    %rdi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
mov    -0x8(%rbp),%rax
movsd  (%rax),%xmm0
mov    -0x10(%rbp),%rax
movsd  (%rax),%xmm1
mov    $0x2,%al
call   1040 <dt2jd@plt>
cvtsi2sd %eax,%xmm0
movsd  %xmm0,-0x18(%rbp)
movsd  -0x18(%rbp),%xmm0
mov    $0x1,%al
call   1060 <utdt@plt>
cvtsi2sd %eax,%xmm0
movsd  %xmm0,-0x20(%rbp)
mov    -0x8(%rbp),%rax
movsd  (%rax),%xmm0
mov    -0x10(%rbp),%rax
movsd  (%rax),%xmm1
mov    $0x2,%al
call   1050 <dt2ts@plt>
cvtsi2sd %eax,%xmm0
movsd  %xmm0,-0x28(%rbp)
movsd  -0x28(%rbp),%xmm0
addsd  -0x20(%rbp),%xmm0
movsd  0xe49(%rip),%xmm1
subsd  %xmm1,%xmm0
movsd  %xmm0,-0x28(%rbp)
movsd  -0x28(%rbp),%xmm0
mov    -0x8(%rbp),%rdi
mov    -0x10(%rbp),%rsi
mov    $0x1,%al
call   1030 <ts2dt@plt>
add    $0x30,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<dt2tai>:
push   %r14
push   %rbx
push   %rax
mov    %rsi,%r14
mov    %rdi,%rbx
movsd  (%rdi),%xmm0
movsd  (%rsi),%xmm1
mov    $0x2,%al
call   1040 <dt2jd@plt>
xorps  %xmm0,%xmm0
cvtsi2sd %eax,%xmm0
mov    $0x1,%al
call   1060 <utdt@plt>
xorps  %xmm0,%xmm0
cvtsi2sd %eax,%xmm0
movsd  %xmm0,(%rsp)
movsd  (%rbx),%xmm0
movsd  (%r14),%xmm1
mov    $0x2,%al
call   1050 <dt2ts@plt>
xorps  %xmm0,%xmm0
cvtsi2sd %eax,%xmm0
addsd  (%rsp),%xmm0
addsd  0xe69(%rip),%xmm0
mov    %rbx,%rdi
mov    %r14,%rsi
mov    $0x1,%al
add    $0x8,%rsp
pop    %rbx
pop    %r14
jmp    1030 <ts2dt@plt>

LLVM IR (-O0):
define void @dt2tai(double* %0, double* %1) {
%3 = alloca double*
%4 = alloca double*
%5 = alloca double
%6 = alloca double
%7 = alloca double
store double* %0, double** %3
store double* %1, double** %4
%8 = load double*, double** %3
%9 = load double, double* %8
%10 = load double*, double** %4
%11 = load double, double* %10
%12 = call i32 (double, double, ...) bitcast (i32 (...)* @dt2jd to i32 (double, double, ...)*)(double %9, double %11)
%13 = sitofp i32 %12 to double
store double %13, double* %5
%14 = load double, double* %5
%15 = call i32 (double, ...) bitcast (i32 (...)* @utdt to i32 (double, ...)*)(double %14)
%16 = sitofp i32 %15 to double
store double %16, double* %6
%17 = load double*, double** %3
%18 = load double, double* %17
%19 = load double*, double** %4
%20 = load double, double* %19
%21 = call i32 (double, double, ...) bitcast (i32 (...)* @dt2ts to i32 (double, double, ...)*)(double %18, double %20)
%22 = sitofp i32 %21 to double
store double %22, double* %7
%23 = load double, double* %7
%24 = load double, double* %6
%25 = fadd double %23, %24
%26 = fsub double %25, 3.218400e+01
store double %26, double* %7
%27 = load double, double* %7
%28 = load double*, double** %3
%29 = load double*, double** %4
%30 = call i32 (double, double*, double*, ...) bitcast (i32 (...)* @ts2dt to i32 (double, double*, double*, ...)*)(double %27, double* %28, double* %29)
ret void
}

LLVM IR (-O2):
define void @dt2tai(double* %0, double* %1) {
%3 = load double, double* %0
%4 = load double, double* %1
%5 = tail call i32 (double, double, ...) bitcast (i32 (...)* @dt2jd to i32 (double, double, ...)*)(double %3, double %4)
%6 = sitofp i32 %5 to double
%7 = tail call i32 (double, ...) bitcast (i32 (...)* @utdt to i32 (double, ...)*)(double %6)
%8 = sitofp i32 %7 to double
%9 = load double, double* %0
%10 = load double, double* %1
%11 = tail call i32 (double, double, ...) bitcast (i32 (...)* @dt2ts to i32 (double, double, ...)*)(double %9, double %10)
%12 = sitofp i32 %11 to double
%13 = fadd double %8, %12
%14 = fadd double %13, -3.218400e+01
%15 = tail call i32 (double, double*, double*, ...) bitcast (i32 (...)* @ts2dt to i32 (double, double*, double*, ...)*)(double %14, double* %0, double* %1)
ret void
}