#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 */
typedef int /*<<< orphan*/ FILE;

/* Variables and functions */
int /*<<< orphan*/ exit(int);
int /*<<< orphan*/ *fopen(char *, char *);
int /*<<< orphan*/ fprintf(int /*<<< orphan*/ *, char *, char *);
int /*<<< orphan*/ perror(char *);
int /*<<< orphan*/ *stderr;
int /*<<< orphan*/ sum(int /*<<< orphan*/ *);
int main(int argc, char **argv) {
  FILE *res;
  if (argc > 2) {
    fprintf(stderr, "Usage:\n\t%s [output]\n", argv[0]);
    exit(1);
  } else if (argc == 2) {
    res = fopen(argv[1], "w");
    if (!res) {
      perror(argv[1]);
      exit(1);
    }
  } else {
    res = stderr;
  }
  sum(res);
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
movl   $0x0,-0x4(%rbp)
mov    %edi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
cmpl   $0x2,-0x8(%rbp)
jle    1197 <main+0x47>
mov    0x2e69(%rip),%rax
mov    (%rax),%rdi
mov    -0x10(%rbp),%rax
mov    (%rax),%rdx
lea    0xe78(%rip),%rsi
call   1030 <fprintf@plt>
mov    $0x1,%edi
call   1070 <exit@plt>
cmpl   $0x2,-0x8(%rbp)
jne    11e0 <main+0x90>
mov    -0x10(%rbp),%rax
mov    0x8(%rax),%rdi
lea    0xe65(%rip),%rsi
call   1050 <fopen@plt>
mov    %rax,-0x18(%rbp)
cmpq   $0x0,-0x18(%rbp)
jne    11db <main+0x8b>
mov    -0x10(%rbp),%rax
mov    0x8(%rax),%rdi
call   1060 <perror@plt>
mov    $0x1,%edi
call   1070 <exit@plt>
jmp    11ee <main+0x9e>
mov    0x2df9(%rip),%rax
mov    (%rax),%rax
mov    %rax,-0x18(%rbp)
jmp    11f3 <main+0xa3>
mov    -0x18(%rbp),%rdi
call   1040 <sum@plt>
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbx
mov    %rsi,%rbx
cmp    $0x3,%edi
jge    119c <main+0x4c>
cmp    $0x2,%edi
jne    1189 <main+0x39>
mov    0x8(%rbx),%rdi
lea    0xeac(%rip),%rsi
call   1050 <fopen@plt>
mov    %rax,%rdi
test   %rax,%rax
jne    1193 <main+0x43>
mov    0x8(%rbx),%rdi
call   1060 <perror@plt>
mov    $0x1,%edi
call   1070 <exit@plt>
mov    0x2e50(%rip),%rax
mov    (%rax),%rdi
call   1040 <sum@plt>
xor    %eax,%eax
pop    %rbx
ret
mov    0x2e3d(%rip),%rax
mov    (%rax),%rdi
mov    (%rbx),%rdx
lea    0xe50(%rip),%rsi
call   1030 <fprintf@plt>
mov    $0x1,%edi
call   1070 <exit@plt>

LLVM IR (-O0):
@stderr = global i32* null
@.str = [21 x i8] c"Usage:\0A\09%s [output]\0A\00"
@.str.1 = [2 x i8] c"w\00"
define i32 @main(i32 %0, i8** %1) {
%3 = alloca i32
%4 = alloca i32
%5 = alloca i8**
%6 = alloca i32*
store i32 0, i32* %3
store i32 %0, i32* %4
store i8** %1, i8*** %5
%7 = load i32, i32* %4
%8 = icmp sgt i32 %7, 2
br i1 %8, label %9, label %16
9: ; preds = %2
%10 = load i32*, i32** @stderr
%11 = load i8**, i8*** %5
%12 = getelementptr inbounds i8*, i8** %11, i64 0
%13 = load i8*, i8** %12
%14 = call i32 @fprintf(i32* %10, i8* getelementptr inbounds ([21 x i8], [21 x i8]* @.str, i64 0, i64 0), i8* %13)
%15 = call i32 @exit(i32 1)
unreachable
16: ; preds = %2
%17 = load i32, i32* %4
%18 = icmp eq i32 %17, 2
br i1 %18, label %19, label %33
19: ; preds = %16
%20 = load i8**, i8*** %5
%21 = getelementptr inbounds i8*, i8** %20, i64 1
%22 = load i8*, i8** %21
%23 = call i32* @fopen(i8* %22, i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.1, i64 0, i64 0))
store i32* %23, i32** %6
%24 = load i32*, i32** %6
%25 = icmp ne i32* %24, null
br i1 %25, label %32, label %26
26: ; preds = %19
%27 = load i8**, i8*** %5
%28 = getelementptr inbounds i8*, i8** %27, i64 1
%29 = load i8*, i8** %28
%30 = call i32 @perror(i8* %29)
%31 = call i32 @exit(i32 1)
unreachable
32: ; preds = %19
br label %35
33: ; preds = %16
%34 = load i32*, i32** @stderr
store i32* %34, i32** %6
br label %35
35: ; preds = %33, %32
br label %36
36: ; preds = %35
%37 = load i32*, i32** %6
%38 = call i32 @sum(i32* %37)
%39 = load i32, i32* %3
ret i32 %39
}

LLVM IR (-O2):
@stderr = global i32* null
@.str = [21 x i8] c"Usage:\0A\09%s [output]\0A\00"
@.str.1 = [2 x i8] c"w\00"
define i32 @main(i32 %0, i8** nocapture %1) {
%3 = icmp sgt i32 %0, 2
br i1 %3, label %4, label %9
4: ; preds = %2
%5 = load i32*, i32** @stderr
%6 = load i8*, i8** %1
%7 = tail call i32 @fprintf(i32* %5, i8* getelementptr inbounds ([21 x i8], [21 x i8]* @.str, i64 0, i64 0), i8* %6)
%8 = tail call i32 @exit(i32 1)
unreachable
9: ; preds = %2
%10 = icmp eq i32 %0, 2
br i1 %10, label %11, label %20
11: ; preds = %9
%12 = getelementptr inbounds i8*, i8** %1, i64 1
%13 = load i8*, i8** %12
%14 = tail call i32* @fopen(i8* %13, i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.1, i64 0, i64 0))
%15 = icmp eq i32* %14, null
br i1 %15, label %16, label %22
16: ; preds = %11
%17 = load i8*, i8** %12
%18 = tail call i32 @perror(i8* %17)
%19 = tail call i32 @exit(i32 1)
unreachable
20: ; preds = %9
%21 = load i32*, i32** @stderr
br label %22
22: ; preds = %20, %11
%23 = phi i32* [ %14, %11 ], [ %21, %20 ]
%24 = tail call i32 @sum(i32* %23)
ret i32 0
}