#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__ _cksum(int, 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();
    }
  return (_cksum(argc - optind, &argv[optind]) == 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   1040 <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    11ae <main+0x7e>
mov    -0x8(%rbp),%edi
mov    0x2e6a(%rip),%rax
sub    (%rax),%edi
mov    -0x10(%rbp),%rsi
mov    0x2e5d(%rip),%rax
movslq (%rax),%rax
shl    $0x3,%rax
add    %rax,%rsi
call   1050 <_cksum@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   %r14
push   %rbx
push   %rax
mov    %rsi,%r14
mov    %edi,%ebx
lea    0xec0(%rip),%rdx
call   1040 <getopt@plt>
cmp    $0xffffffff,%eax
je     1158 <main+0x28>
xor    %eax,%eax
add    $0x8,%rsp
pop    %rbx
pop    %r14
jmp    1030 <_usage@plt>
mov    0x2e89(%rip),%rax
movslq (%rax),%rax
sub    %eax,%ebx
lea    (%r14,%rax,8),%rsi
mov    %ebx,%edi
call   1050 <_cksum@plt>
xor    %ecx,%ecx
test   %rax,%rax
setne  %cl
add    %ecx,%ecx
mov    %ecx,%eax
add    $0x8,%rsp
pop    %rbx
pop    %r14
ret

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 %28
16: ; preds = %7
%17 = load i32, i32* %4
%18 = load i32, i32* @optind
%19 = sub nsw i32 %17, %18
%20 = load i8**, i8*** %5
%21 = load i32, i32* @optind
%22 = sext i32 %21 to i64
%23 = getelementptr inbounds i8*, i8** %20, i64 %22
%24 = call i64 @_cksum(i32 %19, i8** %23)
%25 = icmp eq i64 %24, 0
%26 = zext i1 %25 to i64
%27 = select i1 %25, i32 0, i32 2
store i32 %27, i32* %3
br label %28
28: ; preds = %16, %14
%29 = load i32, i32* %3
ret i32 %29
}

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 %15
7: ; preds = %2
%8 = load i32, i32* @optind
%9 = sub nsw i32 %0, %8
%10 = sext i32 %8 to i64
%11 = getelementptr inbounds i8*, i8** %1, i64 %10
%12 = tail call i64 @_cksum(i32 %9, i8** %11)
%13 = icmp eq i64 %12, 0
%14 = select i1 %13, i32 0, i32 2
br label %15
15: ; preds = %7, %5
%16 = phi i32 [ %6, %5 ], [ %14, %7 ]
ret i32 %16
}