#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 acos(int);
int cos(double const);
int sin(double const);
double calcAngularDist(const double lat1, const double lon1, const double lat2,
                       const double lon2) {
  return acos(sin(lat1) * sin(lat2) + cos(lat1) * cos(lat2) * cos(lon1 - lon2));
}


x86 assembly (clang, -O0):
<calcAngularDist>:
push   %rbp
mov    %rsp,%rbp
sub    $0x30,%rsp
movsd  %xmm0,-0x8(%rbp)
movsd  %xmm1,-0x10(%rbp)
movsd  %xmm2,-0x18(%rbp)
movsd  %xmm3,-0x20(%rbp)
movsd  -0x8(%rbp),%xmm0
call   1040 <sin@plt>
mov    %eax,-0x30(%rbp)
movsd  -0x18(%rbp),%xmm0
call   1040 <sin@plt>
mov    %eax,%ecx
mov    -0x30(%rbp),%eax
imul   %ecx,%eax
mov    %eax,-0x28(%rbp)
movsd  -0x8(%rbp),%xmm0
call   1050 <cos@plt>
mov    %eax,-0x2c(%rbp)
movsd  -0x18(%rbp),%xmm0
call   1050 <cos@plt>
mov    %eax,%ecx
mov    -0x2c(%rbp),%eax
imul   %ecx,%eax
mov    %eax,-0x24(%rbp)
movsd  -0x10(%rbp),%xmm0
subsd  -0x20(%rbp),%xmm0
call   1050 <cos@plt>
mov    -0x28(%rbp),%edi
mov    %eax,%ecx
mov    -0x24(%rbp),%eax
imul   %ecx,%eax
add    %eax,%edi
call   1030 <acos@plt>
add    $0x30,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<calcAngularDist>:
push   %rbp
push   %rbx
sub    $0x28,%rsp
movsd  %xmm3,0x20(%rsp)
movsd  %xmm2,0x8(%rsp)
movsd  %xmm1,0x18(%rsp)
movsd  %xmm0,0x10(%rsp)
call   1040 <sin@plt>
mov    %eax,%ebx
movsd  0x8(%rsp),%xmm0
call   1040 <sin@plt>
imul   %eax,%ebx
movsd  0x10(%rsp),%xmm0
call   1050 <cos@plt>
mov    %eax,%ebp
movsd  0x8(%rsp),%xmm0
call   1050 <cos@plt>
imul   %eax,%ebp
movsd  0x18(%rsp),%xmm0
subsd  0x20(%rsp),%xmm0
call   1050 <cos@plt>
imul   %eax,%ebp
add    %ebx,%ebp
mov    %ebp,%edi
add    $0x28,%rsp
pop    %rbx
pop    %rbp
jmp    1030 <acos@plt>

LLVM IR (-O0):
define double @calcAngularDist(double %0, double %1, double %2, double %3) {
%5 = alloca double
%6 = alloca double
%7 = alloca double
%8 = alloca double
store double %0, double* %5
store double %1, double* %6
store double %2, double* %7
store double %3, double* %8
%9 = load double, double* %5
%10 = call i32 @sin(double %9)
%11 = load double, double* %7
%12 = call i32 @sin(double %11)
%13 = mul nsw i32 %10, %12
%14 = load double, double* %5
%15 = call i32 @cos(double %14)
%16 = load double, double* %7
%17 = call i32 @cos(double %16)
%18 = mul nsw i32 %15, %17
%19 = load double, double* %6
%20 = load double, double* %8
%21 = fsub double %19, %20
%22 = call i32 @cos(double %21)
%23 = mul nsw i32 %18, %22
%24 = add nsw i32 %13, %23
%25 = call double @acos(i32 %24)
ret double %25
}

LLVM IR (-O2):
define double @calcAngularDist(double %0, double %1, double %2, double %3) {
%5 = tail call i32 @sin(double %0)
%6 = tail call i32 @sin(double %2)
%7 = mul nsw i32 %6, %5
%8 = tail call i32 @cos(double %0)
%9 = tail call i32 @cos(double %2)
%10 = mul nsw i32 %9, %8
%11 = fsub double %1, %3
%12 = tail call i32 @cos(double %11)
%13 = mul nsw i32 %10, %12
%14 = add nsw i32 %13, %7
%15 = tail call double @acos(i32 %14)
ret double %15
}