#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 */
scalar_t__ _link(char *, char *);
int _usage();
int getopt(int, char **, char *);
int optind;
int main(int argc, char *argv[]) {
  int o;
  while ((o = getopt(argc, argv, "")) != -1)
    switch (o) {
    default:
      return _usage();
    }
  if (optind != argc - 2)
    return _usage();
  return (_link(argv[optind], argv[optind + 1]) == 0) ? 0 : 2;
}


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)
mov    -0x8(%rbp),%edi
mov    -0x10(%rbp),%rsi
lea    0xeac(%rip),%rdx
call   1050 <getopt@plt>
mov    %eax,-0x14(%rbp)
cmp    $0xffffffff,%eax
je     1174 <main+0x44>
mov    $0x0,%al
call   1030 <_usage@plt>
mov    %eax,-0x4(%rbp)
jmp    11dc <main+0xac>
mov    0x2e6d(%rip),%rax
mov    (%rax),%eax
mov    -0x8(%rbp),%ecx
sub    $0x2,%ecx
cmp    %ecx,%eax
je     119a <main+0x6a>
mov    $0x0,%al
call   1030 <_usage@plt>
mov    %eax,-0x4(%rbp)
jmp    11dc <main+0xac>
mov    -0x10(%rbp),%rax
mov    0x2e43(%rip),%rcx
movslq (%rcx),%rcx
mov    (%rax,%rcx,8),%rdi
mov    -0x10(%rbp),%rax
mov    0x2e31(%rip),%rcx
mov    (%rcx),%ecx
add    $0x1,%ecx
movslq %ecx,%rcx
mov    (%rax,%rcx,8),%rsi
call   1040 <_link@plt>
mov    %rax,%rdx
mov    $0x2,%eax
xor    %ecx,%ecx
cmp    $0x0,%rdx
cmove  %ecx,%eax
mov    %eax,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbp
push   %rbx
push   %rax
mov    %rsi,%rbx
mov    %edi,%ebp
lea    0xec1(%rip),%rdx
call   1050 <getopt@plt>
cmp    $0xffffffff,%eax
jne    117b <main+0x4b>
mov    0x2e98(%rip),%rax
movslq (%rax),%rax
add    $0xfffffffe,%ebp
cmp    %ebp,%eax
jne    117b <main+0x4b>
mov    (%rbx,%rax,8),%rdi
mov    0x8(%rbx,%rax,8),%rsi
call   1040 <_link@plt>
xor    %ecx,%ecx
test   %rax,%rax
setne  %cl
add    %ecx,%ecx
mov    %ecx,%eax
add    $0x8,%rsp
pop    %rbx
pop    %rbp
ret
xor    %eax,%eax
add    $0x8,%rsp
pop    %rbx
pop    %rbp
jmp    1030 <_usage@plt>

LLVM IR (-O0):
@.str = [1 x i8] zeroinitializer
@optind = global i32 0
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
br label %7
7: ; preds = %2
%8 = load i32, i32* %4
%9 = load i8**, i8*** %5
%10 = call i32 @getopt(i32 %8, i8** %9, i8* getelementptr inbounds ([1 x i8], [1 x i8]* @.str, i64 0, i64 0))
store i32 %10, i32* %6
%11 = icmp ne i32 %10, -1
br i1 %11, label %12, label %16
12: ; preds = %7
%13 = load i32, i32* %6
switch i32 %13, label %14 [
]
14: ; preds = %12
%15 = call i32 (...) @_usage()
store i32 %15, i32* %3
br label %39
16: ; preds = %7
%17 = load i32, i32* @optind
%18 = load i32, i32* %4
%19 = sub nsw i32 %18, 2
%20 = icmp ne i32 %17, %19
br i1 %20, label %21, label %23
21: ; preds = %16
%22 = call i32 (...) @_usage()
store i32 %22, i32* %3
br label %39
23: ; preds = %16
%24 = load i8**, i8*** %5
%25 = load i32, i32* @optind
%26 = sext i32 %25 to i64
%27 = getelementptr inbounds i8*, i8** %24, i64 %26
%28 = load i8*, i8** %27
%29 = load i8**, i8*** %5
%30 = load i32, i32* @optind
%31 = add nsw i32 %30, 1
%32 = sext i32 %31 to i64
%33 = getelementptr inbounds i8*, i8** %29, i64 %32
%34 = load i8*, i8** %33
%35 = call i64 @_link(i8* %28, i8* %34)
%36 = icmp eq i64 %35, 0
%37 = zext i1 %36 to i64
%38 = select i1 %36, i32 0, i32 2
store i32 %38, i32* %3
br label %39
39: ; preds = %23, %21, %14
%40 = load i32, i32* %3
ret i32 %40
}

LLVM IR (-O2):
@.str = [1 x i8] zeroinitializer
@optind = global i32 0
define i32 @main(i32 %0, i8** %1) {
%3 = tail call i32 @getopt(i32 %0, i8** %1, i8* getelementptr inbounds ([1 x i8], [1 x i8]* @.str, i64 0, i64 0))
%4 = icmp eq i32 %3, -1
br i1 %4, label %7, label %5
5: ; preds = %2
%6 = tail call i32 (...) @_usage()
br label %24
7: ; preds = %2
%8 = load i32, i32* @optind
%9 = add nsw i32 %0, -2
%10 = icmp eq i32 %8, %9
br i1 %10, label %13, label %11
11: ; preds = %7
%12 = tail call i32 (...) @_usage()
br label %24
13: ; preds = %7
%14 = sext i32 %8 to i64
%15 = getelementptr inbounds i8*, i8** %1, i64 %14
%16 = load i8*, i8** %15
%17 = add nsw i32 %8, 1
%18 = sext i32 %17 to i64
%19 = getelementptr inbounds i8*, i8** %1, i64 %18
%20 = load i8*, i8** %19
%21 = tail call i64 @_link(i8* %16, i8* %20)
%22 = icmp eq i64 %21, 0
%23 = select i1 %22, i32 0, i32 2
br label %24
24: ; preds = %13, %11, %5
%25 = phi i32 [ %6, %5 ], [ %12, %11 ], [ %23, %13 ]
ret i32 %25
}