double hjd(double jd, double dra, double ddec) {
  double e;
  double n;
  double g;
  double L;
  double l;
  double R;
  double X, Y;
  double cdec, sdec;
  double cra, sra;
  double deltajd;
  double ra, dec;
  ra = ((((dra)*180. / 3.141592653589793)) / 15.);
  dec = ((ddec)*180. / 3.141592653589793);
  precess((double)(2451545.0 - 2415020.0), (double)(jd - 2415020.0), &ra, &dec);
  cdec = cos(dec);
  sdec = sin(dec);
  cra = cos(ra);
  sra = sin(ra);
  n = jd - 2451545.0;
  e = ((23.439 - 0.0000004 * n) * 3.141592653589793 / 180.);
  g = ((357.528) * 3.141592653589793 / 180.) +
      ((0.9856003) * 3.141592653589793 / 180.) * n;
  L = ((280.461) * 3.141592653589793 / 180.) +
      ((0.9856474) * 3.141592653589793 / 180.) * n;
  l = L + ((1.915) * 3.141592653589793 / 180.) * sin(g) +
      ((0.02) * 3.141592653589793 / 180.) * sin(2.0 * g);
  R = 1.00014 - 0.01671 * cos(g) - 0.00014 * cos(2.0 * g);
  X = R * cos(l);
  Y = R * cos(e) * sin(l);
  deltajd = 0.0057755 * (cdec * cra * X + (cdec * sra + tan(e) * sdec) * Y);
  return (jd - deltajd);
}


x86 assembly (clang, -O0):
<hjd>:
push   %rbp
mov    %rsp,%rbp
sub    $0xe0,%rsp
movsd  %xmm0,-0x8(%rbp)
movsd  %xmm1,-0x10(%rbp)
movsd  %xmm2,-0x18(%rbp)
movsd  0xef6(%rip),%xmm0
mulsd  -0x10(%rbp),%xmm0
movsd  0xef1(%rip),%xmm1
divsd  %xmm1,%xmm0
movsd  0xf15(%rip),%xmm1
divsd  %xmm1,%xmm0
movsd  %xmm0,-0x88(%rbp)
ff
movsd  0xec9(%rip),%xmm0
mulsd  -0x18(%rbp),%xmm0
movsd  0xec4(%rip),%xmm1
divsd  %xmm1,%xmm0
movsd  %xmm0,-0x90(%rbp)
ff
movsd  -0x8(%rbp),%xmm1
movsd  0xed3(%rip),%xmm0
subsd  %xmm0,%xmm1
movsd  0xebf(%rip),%xmm0
lea    -0x88(%rbp),%rdi
lea    -0x90(%rbp),%rsi
mov    $0x2,%al
call   1040 <precess@plt>
movsd  -0x90(%rbp),%xmm0
ff
call   1060 <cos@plt>
movsd  %xmm0,-0x60(%rbp)
movsd  -0x90(%rbp),%xmm0
ff
call   1030 <sin@plt>
movsd  %xmm0,-0x68(%rbp)
movsd  -0x88(%rbp),%xmm0
ff
call   1060 <cos@plt>
movsd  %xmm0,-0x70(%rbp)
movsd  -0x88(%rbp),%xmm0
ff
call   1030 <sin@plt>
movsd  %xmm0,-0x78(%rbp)
movsd  -0x8(%rbp),%xmm0
movsd  0xe4d(%rip),%xmm1
subsd  %xmm1,%xmm0
movsd  %xmm0,-0x28(%rbp)
movsd  -0x28(%rbp),%xmm0
movsd  0xe27(%rip),%xmm1
mulsd  %xmm1,%xmm0
movsd  0xe23(%rip),%xmm1
addsd  %xmm1,%xmm0
movsd  0xe07(%rip),%xmm1
mulsd  %xmm1,%xmm0
movsd  0xdf3(%rip),%xmm1
divsd  %xmm1,%xmm0
movsd  %xmm0,-0x20(%rbp)
movsd  -0x28(%rbp),%xmm0
movsd  0xdcd(%rip),%xmm1
mulsd  %xmm1,%xmm0
movsd  0xdc9(%rip),%xmm1
addsd  %xmm1,%xmm0
movsd  %xmm0,-0x30(%rbp)
movsd  -0x28(%rbp),%xmm0
movsd  0xd9b(%rip),%xmm1
mulsd  %xmm1,%xmm0
movsd  0xd97(%rip),%xmm1
addsd  %xmm1,%xmm0
movsd  %xmm0,-0x38(%rbp)
movsd  -0x38(%rbp),%xmm0
movsd  %xmm0,-0xe0(%rbp)
ff
movsd  -0x30(%rbp),%xmm0
call   1030 <sin@plt>
movsd  -0xe0(%rbp),%xmm1
ff
movsd  0xd57(%rip),%xmm2
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
movsd  %xmm0,-0xd8(%rbp)
ff
movsd  0xd1f(%rip),%xmm0
mulsd  -0x30(%rbp),%xmm0
call   1030 <sin@plt>
movsd  -0xd8(%rbp),%xmm1
ff
movsd  0xd1d(%rip),%xmm2
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
movsd  %xmm0,-0x40(%rbp)
movsd  -0x30(%rbp),%xmm0
call   1060 <cos@plt>
movsd  0xcee(%rip),%xmm1
mulsd  %xmm1,%xmm0
movsd  0xcea(%rip),%xmm1
addsd  %xmm1,%xmm0
movsd  %xmm0,-0xd0(%rbp)
ff
movsd  0xcc6(%rip),%xmm0
mulsd  -0x30(%rbp),%xmm0
call   1060 <cos@plt>
movsd  -0xd0(%rbp),%xmm1
ff
movsd  0xca4(%rip),%xmm2
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
movsd  %xmm0,-0x48(%rbp)
movsd  -0x48(%rbp),%xmm0
movsd  %xmm0,-0xc8(%rbp)
ff
movsd  -0x40(%rbp),%xmm0
call   1060 <cos@plt>
movaps %xmm0,%xmm1
movsd  -0xc8(%rbp),%xmm0
ff
mulsd  %xmm1,%xmm0
movsd  %xmm0,-0x50(%rbp)
movsd  -0x48(%rbp),%xmm0
movsd  %xmm0,-0xc0(%rbp)
ff
movsd  -0x20(%rbp),%xmm0
call   1060 <cos@plt>
movaps %xmm0,%xmm1
movsd  -0xc0(%rbp),%xmm0
ff
mulsd  %xmm1,%xmm0
movsd  %xmm0,-0xb8(%rbp)
ff
movsd  -0x40(%rbp),%xmm0
call   1030 <sin@plt>
movaps %xmm0,%xmm1
movsd  -0xb8(%rbp),%xmm0
ff
mulsd  %xmm1,%xmm0
movsd  %xmm0,-0x58(%rbp)
movsd  -0x60(%rbp),%xmm0
mulsd  -0x70(%rbp),%xmm0
movsd  %xmm0,-0xa8(%rbp)
ff
movsd  -0x50(%rbp),%xmm0
movsd  %xmm0,-0xa0(%rbp)
ff
movsd  -0x60(%rbp),%xmm0
movsd  %xmm0,-0x98(%rbp)
ff
movsd  -0x78(%rbp),%xmm0
movsd  %xmm0,-0xb0(%rbp)
ff
movsd  -0x20(%rbp),%xmm0
call   1050 <tan@plt>
movsd  -0xb0(%rbp),%xmm4
ff
movsd  -0xa8(%rbp),%xmm1
ff
movsd  -0xa0(%rbp),%xmm2
ff
movaps %xmm0,%xmm3
movsd  -0x98(%rbp),%xmm0
ff
mulsd  -0x68(%rbp),%xmm3
mulsd  %xmm4,%xmm0
addsd  %xmm3,%xmm0
mulsd  -0x58(%rbp),%xmm0
mulsd  %xmm2,%xmm1
addsd  %xmm0,%xmm1
movsd  0xb90(%rip),%xmm0
mulsd  %xmm1,%xmm0
movsd  %xmm0,-0x80(%rbp)
movsd  -0x8(%rbp),%xmm0
subsd  -0x80(%rbp),%xmm0
add    $0xe0,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<hjd>:
sub    $0x58,%rsp
movsd  %xmm0,0x40(%rsp)
movsd  0xeae(%rip),%xmm3
mulsd  %xmm3,%xmm1
movsd  0xeaa(%rip),%xmm4
divsd  %xmm4,%xmm1
divsd  0xea6(%rip),%xmm1
movsd  %xmm1,0x28(%rsp)
mulsd  %xmm3,%xmm2
divsd  %xmm4,%xmm2
movsd  %xmm2,0x20(%rsp)
movsd  0xe92(%rip),%xmm1
addsd  %xmm0,%xmm1
movsd  0xe8e(%rip),%xmm0
lea    0x28(%rsp),%rdi
lea    0x20(%rsp),%rsi
mov    $0x2,%al
call   1040 <precess@plt>
movsd  0x20(%rsp),%xmm0
call   1060 <cos@plt>
movsd  %xmm0,0x38(%rsp)
movsd  0x20(%rsp),%xmm0
call   1030 <sin@plt>
movsd  %xmm0,0x50(%rsp)
movsd  0x28(%rsp),%xmm0
call   1060 <cos@plt>
movsd  %xmm0,0x18(%rsp)
movsd  0x28(%rsp),%xmm0
call   1030 <sin@plt>
movsd  %xmm0,0x48(%rsp)
movsd  0xe39(%rip),%xmm1
addsd  0x40(%rsp),%xmm1
movsd  0xe33(%rip),%xmm0
mulsd  %xmm1,%xmm0
addsd  0xe2f(%rip),%xmm0
mulsd  0xdf7(%rip),%xmm0
divsd  0xde7(%rip),%xmm0
movsd  %xmm0,0x30(%rsp)
movsd  0xe19(%rip),%xmm0
mulsd  %xmm1,%xmm0
addsd  0xe15(%rip),%xmm0
movsd  %xmm0,(%rsp)
mulsd  0xe10(%rip),%xmm1
addsd  0xe10(%rip),%xmm1
movsd  %xmm1,0x8(%rsp)
call   1030 <sin@plt>
mulsd  0xe05(%rip),%xmm0
addsd  0x8(%rsp),%xmm0
movsd  %xmm0,0x8(%rsp)
movsd  (%rsp),%xmm0
addsd  %xmm0,%xmm0
movsd  %xmm0,0x10(%rsp)
call   1030 <sin@plt>
mulsd  0xde5(%rip),%xmm0
addsd  0x8(%rsp),%xmm0
movsd  %xmm0,0x8(%rsp)
movsd  (%rsp),%xmm0
call   1060 <cos@plt>
mulsd  0xdcf(%rip),%xmm0
addsd  0xdcf(%rip),%xmm0
movsd  %xmm0,(%rsp)
movsd  0x10(%rsp),%xmm0
call   1060 <cos@plt>
mulsd  0xdbf(%rip),%xmm0
addsd  (%rsp),%xmm0
movsd  %xmm0,(%rsp)
movsd  0x8(%rsp),%xmm0
call   1060 <cos@plt>
mulsd  (%rsp),%xmm0
movsd  %xmm0,0x10(%rsp)
movsd  0x30(%rsp),%xmm0
call   1060 <cos@plt>
mulsd  (%rsp),%xmm0
movsd  %xmm0,(%rsp)
movsd  0x8(%rsp),%xmm0
call   1030 <sin@plt>
mulsd  (%rsp),%xmm0
movsd  %xmm0,0x8(%rsp)
movsd  0x18(%rsp),%xmm0
mulsd  0x38(%rsp),%xmm0
mulsd  0x10(%rsp),%xmm0
movsd  %xmm0,0x18(%rsp)
movsd  0x30(%rsp),%xmm0
call   1050 <tan@plt>
mulsd  0x50(%rsp),%xmm0
movsd  0x48(%rsp),%xmm1
mulsd  0x38(%rsp),%xmm1
addsd  %xmm1,%xmm0
mulsd  0x8(%rsp),%xmm0
addsd  0x18(%rsp),%xmm0
mulsd  0xd2f(%rip),%xmm0
addsd  0x40(%rsp),%xmm0
add    $0x58,%rsp
ret

LLVM IR (-O0):
define double @hjd(double %0, double %1, double %2) {
%4 = alloca double
%5 = alloca double
%6 = alloca double
%7 = alloca double
%8 = alloca double
%9 = alloca double
%10 = alloca double
%11 = alloca double
%12 = alloca double
%13 = alloca double
%14 = alloca double
%15 = alloca double
%16 = alloca double
%17 = alloca double
%18 = alloca double
%19 = alloca double
%20 = alloca double
%21 = alloca double
store double %0, double* %4
store double %1, double* %5
store double %2, double* %6
%22 = load double, double* %5
%23 = fmul double %22, 1.800000e+02
%24 = fdiv double %23, 0x400921FB54442D18
%25 = fdiv double %24, 1.500000e+01
store double %25, double* %20
%26 = load double, double* %6
%27 = fmul double %26, 1.800000e+02
%28 = fdiv double %27, 0x400921FB54442D18
store double %28, double* %21
%29 = load double, double* %4
%30 = fsub double %29, 2.415020e+06
%31 = call i32 (double, double, double*, double*, ...) bitcast (i32 (...)* @precess to i32 (double, double, double*, double*, ...)*)(double 3.652500e+04, double %30, double* %20, double* %21)
%32 = load double, double* %21
%33 = call double @cos(double %32)
store double %33, double* %15
%34 = load double, double* %21
%35 = call double @sin(double %34)
store double %35, double* %16
%36 = load double, double* %20
%37 = call double @cos(double %36)
store double %37, double* %17
%38 = load double, double* %20
%39 = call double @sin(double %38)
store double %39, double* %18
%40 = load double, double* %4
%41 = fsub double %40, 0x4142B42C80000000
store double %41, double* %8
%42 = load double, double* %8
%43 = call double @llvm.fmuladd.f64(double -4.000000e-07, double %42, double 2.343900e+01)
%44 = fmul double %43, 0x400921FB54442D18
%45 = fdiv double %44, 1.800000e+02
store double %45, double* %7
%46 = load double, double* %8
%47 = call double @llvm.fmuladd.f64(double 0x3F919D64B035FA36, double %46, double 0x4018F5CD3F424640)
store double %47, double* %9
%48 = load double, double* %8
%49 = call double @llvm.fmuladd.f64(double 0x3F919D9BDAEC741A, double %48, double 0x40139472754D8290)
store double %49, double* %10
%50 = load double, double* %10
%51 = load double, double* %9
%52 = call double @sin(double %51)
%53 = call double @llvm.fmuladd.f64(double 0x3FA11CD3A1D2F16B, double %52, double %50)
%54 = load double, double* %9
%55 = fmul double 2.000000e+00, %54
%56 = call double @sin(double %55)
%57 = call double @llvm.fmuladd.f64(double 0x3F36E05A695F8191, double %56, double %53)
store double %57, double* %11
%58 = load double, double* %9
%59 = call double @cos(double %58)
%60 = call double @llvm.fmuladd.f64(double -1.671000e-02, double %59, double 1.000140e+00)
%61 = load double, double* %9
%62 = fmul double 2.000000e+00, %61
%63 = call double @cos(double %62)
%64 = call double @llvm.fmuladd.f64(double -1.400000e-04, double %63, double %60)
store double %64, double* %12
%65 = load double, double* %12
%66 = load double, double* %11
%67 = call double @cos(double %66)
%68 = fmul double %65, %67
store double %68, double* %13
%69 = load double, double* %12
%70 = load double, double* %7
%71 = call double @cos(double %70)
%72 = fmul double %69, %71
%73 = load double, double* %11
%74 = call double @sin(double %73)
%75 = fmul double %72, %74
store double %75, double* %14
%76 = load double, double* %15
%77 = load double, double* %17
%78 = fmul double %76, %77
%79 = load double, double* %13
%80 = load double, double* %15
%81 = load double, double* %18
%82 = load double, double* %7
%83 = call double @tan(double %82)
%84 = load double, double* %16
%85 = fmul double %83, %84
%86 = call double @llvm.fmuladd.f64(double %80, double %81, double %85)
%87 = load double, double* %14
%88 = fmul double %86, %87
%89 = call double @llvm.fmuladd.f64(double %78, double %79, double %88)
%90 = fmul double 5.775500e-03, %89
store double %90, double* %19
%91 = load double, double* %4
%92 = load double, double* %19
%93 = fsub double %91, %92
ret double %93
}

LLVM IR (-O2):
define double @hjd(double %0, double %1, double %2) {
%4 = alloca double
%5 = alloca double
%6 = bitcast double* %4 to i8*
%7 = bitcast double* %5 to i8*
%8 = fmul double %1, 1.800000e+02
%9 = fdiv double %8, 0x400921FB54442D18
%10 = fdiv double %9, 1.500000e+01
store double %10, double* %4
%11 = fmul double %2, 1.800000e+02
%12 = fdiv double %11, 0x400921FB54442D18
store double %12, double* %5
%13 = fadd double %0, -2.415020e+06
%14 = call i32 (double, double, double*, double*, ...) bitcast (i32 (...)* @precess to i32 (double, double, double*, double*, ...)*)(double 3.652500e+04, double %13, double* %4, double* %5)
%15 = load double, double* %5
%16 = call double @cos(double %15)
%17 = load double, double* %5
%18 = call double @sin(double %17)
%19 = load double, double* %4
%20 = call double @cos(double %19)
%21 = load double, double* %4
%22 = call double @sin(double %21)
%23 = fadd double %0, 0xC142B42C80000000
%24 = call double @llvm.fmuladd.f64(double %23, double -4.000000e-07, double 2.343900e+01)
%25 = fmul double %24, 0x400921FB54442D18
%26 = fdiv double %25, 1.800000e+02
%27 = call double @llvm.fmuladd.f64(double %23, double 0x3F919D64B035FA36, double 0x4018F5CD3F424640)
%28 = call double @llvm.fmuladd.f64(double %23, double 0x3F919D9BDAEC741A, double 0x40139472754D8290)
%29 = call double @sin(double %27)
%30 = call double @llvm.fmuladd.f64(double %29, double 0x3FA11CD3A1D2F16B, double %28)
%31 = fmul double %27, 2.000000e+00
%32 = call double @sin(double %31)
%33 = call double @llvm.fmuladd.f64(double %32, double 0x3F36E05A695F8191, double %30)
%34 = call double @cos(double %27)
%35 = call double @llvm.fmuladd.f64(double %34, double -1.671000e-02, double 1.000140e+00)
%36 = call double @cos(double %31)
%37 = call double @llvm.fmuladd.f64(double %36, double -1.400000e-04, double %35)
%38 = call double @cos(double %33)
%39 = fmul double %37, %38
%40 = call double @cos(double %26)
%41 = fmul double %37, %40
%42 = call double @sin(double %33)
%43 = fmul double %41, %42
%44 = fmul double %16, %20
%45 = call double @tan(double %26)
%46 = fmul double %18, %45
%47 = call double @llvm.fmuladd.f64(double %16, double %22, double %46)
%48 = fmul double %43, %47
%49 = call double @llvm.fmuladd.f64(double %44, double %39, double %48)
%50 = fmul double %49, 5.775500e-03
%51 = fsub double %0, %50
ret double %51
}