#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 */
int /*<<< orphan*/ atoi(char *);
int /*<<< orphan*/ exit(int);
int my_dup2(int /*<<< orphan*/, int /*<<< orphan*/);
int new_fd;
int /*<<< orphan*/ printf(char *, ...);
int main(int argc, char *argv[]) {
  if (argc != 3) {
    printf("usage: dup2 src_fd new_fd\n");
    exit(1);
  }
  int new_fd = new_fd = my_dup2(atoi(argv[1]), atoi(argv[2]));
  if (new_fd == -1) {
    printf("dup to new_fd error!\n");
    exit(1);
  }
  printf("\n[main]: new fd is %d\n", new_fd);
  return new_fd;
}


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   $0x3,-0x8(%rbp)
je     1178 <main+0x38>
lea    0xe99(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    $0x1,%edi
call   1060 <exit@plt>
mov    -0x10(%rbp),%rax
mov    0x8(%rax),%rdi
call   1050 <atoi@plt>
mov    %eax,-0x18(%rbp)
mov    -0x10(%rbp),%rax
mov    0x10(%rax),%rdi
call   1050 <atoi@plt>
mov    -0x18(%rbp),%edi
mov    %eax,%esi
call   1040 <my_dup2@plt>
mov    %eax,-0x14(%rbp)
mov    %eax,-0x14(%rbp)
cmpl   $0xffffffff,-0x14(%rbp)
jne    11c7 <main+0x87>
lea    0xe65(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    $0x1,%edi
call   1060 <exit@plt>
mov    -0x14(%rbp),%esi
lea    0xe60(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    -0x14(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbp
push   %rbx
push   %rax
cmp    $0x3,%edi
jne    1198 <main+0x48>
mov    %rsi,%rbx
mov    0x8(%rsi),%rdi
call   1060 <atoi@plt>
mov    %eax,%ebp
mov    0x10(%rbx),%rdi
call   1060 <atoi@plt>
mov    %ebp,%edi
mov    %eax,%esi
call   1050 <my_dup2@plt>
cmp    $0xffffffff,%eax
je     11a1 <main+0x51>
mov    %eax,%ebx
lea    0xe7a(%rip),%rdi
mov    %eax,%esi
xor    %eax,%eax
call   1040 <printf@plt>
mov    %ebx,%eax
add    $0x8,%rsp
pop    %rbx
pop    %rbp
ret
lea    0xe8d(%rip),%rdi
jmp    11a8 <main+0x58>
lea    0xe6f(%rip),%rdi
call   1030 <puts@plt>
mov    $0x1,%edi
call   1070 <exit@plt>

LLVM IR (-O0):
@.str = [27 x i8] c"usage: dup2 src_fd new_fd\0A\00"
@.str.1 = [22 x i8] c"dup to new_fd error!\0A\00"
@.str.2 = [23 x i8] c"\0A[main]: new fd is %d\0A\00"
@new_fd = 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
%7 = load i32, i32* %4
%8 = icmp ne i32 %7, 3
br i1 %8, label %9, label %12
9: ; preds = %2
%10 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([27 x i8], [27 x i8]* @.str, i64 0, i64 0))
%11 = call i32 @exit(i32 1)
unreachable
12: ; preds = %2
%13 = load i8**, i8*** %5
%14 = getelementptr inbounds i8*, i8** %13, i64 1
%15 = load i8*, i8** %14
%16 = call i32 @atoi(i8* %15)
%17 = load i8**, i8*** %5
%18 = getelementptr inbounds i8*, i8** %17, i64 2
%19 = load i8*, i8** %18
%20 = call i32 @atoi(i8* %19)
%21 = call i32 @my_dup2(i32 %16, i32 %20)
store i32 %21, i32* %6
store i32 %21, i32* %6
%22 = load i32, i32* %6
%23 = icmp eq i32 %22, -1
br i1 %23, label %24, label %27
24: ; preds = %12
%25 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([22 x i8], [22 x i8]* @.str.1, i64 0, i64 0))
%26 = call i32 @exit(i32 1)
unreachable
27: ; preds = %12
%28 = load i32, i32* %6
%29 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([23 x i8], [23 x i8]* @.str.2, i64 0, i64 0), i32 %28)
%30 = load i32, i32* %6
ret i32 %30
}

LLVM IR (-O2):
@.str.2 = [23 x i8] c"\0A[main]: new fd is %d\0A\00"
@new_fd = global i32 0
@str = [21 x i8] c"dup to new_fd error!\00"
@str.3 = [26 x i8] c"usage: dup2 src_fd new_fd\00"
define i32 @main(i32 %0, i8** nocapture %1) {
%3 = icmp eq i32 %0, 3
br i1 %3, label %7, label %4
4: ; preds = %2
%5 = tail call i32 @puts(i8* dereferenceable(1) getelementptr inbounds ([26 x i8], [26 x i8]* @str.3, i64 0, i64 0))
%6 = tail call i32 @exit(i32 1)
unreachable
7: ; preds = %2
%8 = getelementptr inbounds i8*, i8** %1, i64 1
%9 = load i8*, i8** %8
%10 = tail call i32 @atoi(i8* %9)
%11 = getelementptr inbounds i8*, i8** %1, i64 2
%12 = load i8*, i8** %11
%13 = tail call i32 @atoi(i8* %12)
%14 = tail call i32 @my_dup2(i32 %10, i32 %13)
%15 = icmp eq i32 %14, -1
br i1 %15, label %16, label %19
16: ; preds = %7
%17 = tail call i32 @puts(i8* dereferenceable(1) getelementptr inbounds ([21 x i8], [21 x i8]* @str, i64 0, i64 0))
%18 = tail call i32 @exit(i32 1)
unreachable
19: ; preds = %7
%20 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([23 x i8], [23 x i8]* @.str.2, i64 0, i64 0), i32 %14)
ret i32 %14
}