#define NULL ((void *)0)
typedef unsigned long size_t; // Customize by platform.
typedef long intptr_t;
typedef unsigned long uintptr_t;
typedef long scalar_t__; // Either arithmetic or pointer type.
/* By default, we understand bool (as a convenience). */
typedef int bool;
#define false 0
#define true 1

/* Forward declarations */

/* Type definitions */

/* Variables and functions */
double erfc(double);
double log(double);
double pow(double, int);
double sqrt(double);
double big_tau(double tau) {
  double bb, v1, beta;
  bb = 9.2e-3 / 1.0e0;
  v1 = 5.0e2 / 1.0e0;
  beta = (pow(tau, -1e0) * pow(log(tau / sqrt(3.1415926536)), -5.0e-1) +
          pow((bb / tau), 5.0e-1)) *
         erfc(sqrt(tau * bb / (3.1415926536 * pow(v1, 2e0))));
  return beta;
}


x86 assembly (clang, -O0):
<big_tau>:
push   %rbp
mov    %rsp,%rbp
sub    $0x50,%rsp
movsd  %xmm0,-0x8(%rbp)
movsd  0xebb(%rip),%xmm0
movsd  %xmm0,-0x10(%rbp)
movsd  0xea6(%rip),%xmm0
movsd  %xmm0,-0x18(%rbp)
movsd  -0x8(%rbp),%xmm0
mov    $0xffffffff,%edi
call   1040 <pow@plt>
movsd  %xmm0,-0x38(%rbp)
movsd  -0x8(%rbp),%xmm0
movsd  %xmm0,-0x48(%rbp)
movsd  0xe73(%rip),%xmm0
call   1050 <sqrt@plt>
movaps %xmm0,%xmm1
movsd  -0x48(%rbp),%xmm0
divsd  %xmm1,%xmm0
call   1030 <log@plt>
xor    %edi,%edi
call   1040 <pow@plt>
movsd  %xmm0,-0x40(%rbp)
movsd  -0x10(%rbp),%xmm0
divsd  -0x8(%rbp),%xmm0
xor    %edi,%edi
call   1040 <pow@plt>
movsd  -0x40(%rbp),%xmm2
movaps %xmm0,%xmm1
movsd  -0x38(%rbp),%xmm0
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
movsd  %xmm0,-0x28(%rbp)
movsd  -0x8(%rbp),%xmm0
mulsd  -0x10(%rbp),%xmm0
movsd  %xmm0,-0x30(%rbp)
movsd  -0x18(%rbp),%xmm0
mov    $0x2,%edi
call   1040 <pow@plt>
movaps %xmm0,%xmm2
movsd  -0x30(%rbp),%xmm0
movsd  0xdf8(%rip),%xmm1
mulsd  %xmm2,%xmm1
divsd  %xmm1,%xmm0
call   1050 <sqrt@plt>
call   1060 <erfc@plt>
movaps %xmm0,%xmm1
movsd  -0x28(%rbp),%xmm0
mulsd  %xmm1,%xmm0
movsd  %xmm0,-0x20(%rbp)
movsd  -0x20(%rbp),%xmm0
add    $0x50,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<big_tau>:
sub    $0x18,%rsp
movsd  %xmm0,(%rsp)
mov    $0xffffffff,%edi
call   1040 <pow@plt>
movsd  %xmm0,0x10(%rsp)
movsd  (%rsp),%xmm0
divsd  0xe9a(%rip),%xmm0
call   1030 <log@plt>
xor    %edi,%edi
call   1040 <pow@plt>
movsd  %xmm0,0x8(%rsp)
movsd  0xe88(%rip),%xmm0
divsd  (%rsp),%xmm0
xor    %edi,%edi
call   1040 <pow@plt>
movsd  0x8(%rsp),%xmm1
mulsd  0x10(%rsp),%xmm1
addsd  %xmm0,%xmm1
movsd  %xmm1,0x8(%rsp)
movsd  (%rsp),%xmm0
mulsd  0xe59(%rip),%xmm0
movsd  %xmm0,(%rsp)
movsd  0xe54(%rip),%xmm0
mov    $0x2,%edi
call   1040 <pow@plt>
mulsd  0xe4a(%rip),%xmm0
movsd  (%rsp),%xmm1
divsd  %xmm0,%xmm1
xorpd  %xmm0,%xmm0
ucomisd %xmm0,%xmm1
movapd %xmm1,%xmm0
jb     11eb <big_tau+0xab>
sqrtsd %xmm0,%xmm0
jmp    11f0 <big_tau+0xb0>
call   1050 <sqrt@plt>
call   1060 <erfc@plt>
mulsd  0x8(%rsp),%xmm0
add    $0x18,%rsp
ret

LLVM IR (-O0):
define double @big_tau(double %0) {
%2 = alloca double
%3 = alloca double
%4 = alloca double
%5 = alloca double
store double %0, double* %2
store double 0x3F82D77318FC5048, double* %3
store double 5.000000e+02, double* %4
%6 = load double, double* %2
%7 = call double @pow(double %6, i32 -1)
%8 = load double, double* %2
%9 = call double @sqrt(double 0x400921FB544486E0)
%10 = fdiv double %8, %9
%11 = call double @log(double %10)
%12 = call double @pow(double %11, i32 0)
%13 = load double, double* %3
%14 = load double, double* %2
%15 = fdiv double %13, %14
%16 = call double @pow(double %15, i32 0)
%17 = call double @llvm.fmuladd.f64(double %7, double %12, double %16)
%18 = load double, double* %2
%19 = load double, double* %3
%20 = fmul double %18, %19
%21 = load double, double* %4
%22 = call double @pow(double %21, i32 2)
%23 = fmul double 0x400921FB544486E0, %22
%24 = fdiv double %20, %23
%25 = call double @sqrt(double %24)
%26 = call double @erfc(double %25)
%27 = fmul double %17, %26
store double %27, double* %5
%28 = load double, double* %5
ret double %28
}

LLVM IR (-O2):
define double @big_tau(double %0) {
%2 = tail call double @pow(double %0, i32 -1)
%3 = fdiv double %0, 0x3FFC5BF891B52212
%4 = tail call double @log(double %3)
%5 = tail call double @pow(double %4, i32 0)
%6 = fdiv double 0x3F82D77318FC5048, %0
%7 = tail call double @pow(double %6, i32 0)
%8 = tail call double @llvm.fmuladd.f64(double %2, double %5, double %7)
%9 = fmul double %0, 0x3F82D77318FC5048
%10 = tail call double @pow(double 5.000000e+02, i32 2)
%11 = fmul double %10, 0x400921FB544486E0
%12 = fdiv double %9, %11
%13 = tail call double @sqrt(double %12)
%14 = tail call double @erfc(double %13)
%15 = fmul double %8, %14
ret double %15
}