#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*/ IPPROTO_UDP;
int /*<<< orphan*/ PF_INET;
int /*<<< orphan*/ SOCK_DGRAM;
int bind(int, struct sockaddr *, int);
int /*<<< orphan*/ htons(int);
int /*<<< orphan*/ memset(struct sockaddr_in *, int /*<<< orphan*/, int);
int socket(int /*<<< orphan*/, int /*<<< orphan*/, int /*<<< orphan*/);
int udp_socket_listen(int port) {
  int sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
  if (sock < 0)
    return -1;
  struct sockaddr_in listen_addr;
  memset(&listen_addr, 0, sizeof(struct sockaddr_in));
  listen_addr.sin_family = AF_INET;
  listen_addr.sin_port = htons(port);
  listen_addr.sin_addr.s_addr = INADDR_ANY;
  int res =
      bind(sock, (struct sockaddr *)&listen_addr, sizeof(struct sockaddr_in));
  if (res < 0)
    return -2;
  return sock;
}


x86 assembly (clang, -O0):
<udp_socket_listen>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
mov    %edi,-0x8(%rbp)
mov    0x2e76(%rip),%rax
mov    (%rax),%edi
mov    0x2e7d(%rip),%rax
mov    (%rax),%esi
mov    0x2e54(%rip),%rax
mov    (%rax),%edx
call   1060 <socket@plt>
mov    %eax,-0xc(%rbp)
cmpl   $0x0,-0xc(%rbp)
jge    1184 <udp_socket_listen+0x44>
movl   $0xffffffff,-0x4(%rbp)
jmp    11e7 <udp_socket_listen+0xa7>
lea    -0x18(%rbp),%rdi
xor    %esi,%esi
mov    $0xc,%edx
call   1040 <memset@plt>
mov    0x2e4d(%rip),%rax
mov    (%rax),%eax
mov    %eax,-0x10(%rbp)
mov    -0x8(%rbp),%edi
call   1030 <htons@plt>
mov    %eax,-0x14(%rbp)
mov    0x2e2e(%rip),%rax
mov    (%rax),%eax
mov    %eax,-0x18(%rbp)
mov    -0xc(%rbp),%edi
lea    -0x18(%rbp),%rsi
mov    $0xc,%edx
call   1050 <bind@plt>
mov    %eax,-0x1c(%rbp)
cmpl   $0x0,-0x1c(%rbp)
jge    11e1 <udp_socket_listen+0xa1>
movl   $0xfffffffe,-0x4(%rbp)
jmp    11e7 <udp_socket_listen+0xa7>
mov    -0xc(%rbp),%eax
mov    %eax,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<udp_socket_listen>:
push   %rbp
push   %r14
push   %rbx
sub    $0x10,%rsp
mov    %edi,%ebp
mov    0x2e77(%rip),%rax
mov    (%rax),%edi
mov    0x2e7e(%rip),%rax
mov    (%rax),%esi
mov    0x2e55(%rip),%rax
mov    (%rax),%edx
call   1060 <socket@plt>
test   %eax,%eax
js     11c1 <udp_socket_listen+0x81>
mov    %eax,%ebx
mov    %rsp,%r14
mov    %r14,%rdi
xor    %esi,%esi
mov    $0xc,%edx
call   1040 <memset@plt>
mov    0x2e5f(%rip),%rax
mov    (%rax),%eax
mov    %eax,0x8(%rsp)
mov    %ebp,%edi
call   1030 <htons@plt>
mov    %eax,0x4(%rsp)
mov    0x2e3f(%rip),%rax
mov    (%rax),%eax
mov    %eax,(%rsp)
mov    %ebx,%edi
mov    %r14,%rsi
mov    $0xc,%edx
call   1050 <bind@plt>
test   %eax,%eax
mov    $0xfffffffe,%eax
cmovns %ebx,%eax
jmp    11c6 <udp_socket_listen+0x86>
mov    $0xffffffff,%eax
add    $0x10,%rsp
pop    %rbx
pop    %r14
pop    %rbp
ret

LLVM IR (-O0):
%struct.sockaddr_in = type { %struct.TYPE_2__, i32, i32 }
%struct.TYPE_2__ = type { i32 }
%struct.sockaddr = type { i32 }
@PF_INET = global i32 0
@SOCK_DGRAM = global i32 0
@IPPROTO_UDP = global i32 0
@AF_INET = global i32 0
@INADDR_ANY = global i32 0
define i32 @udp_socket_listen(i32 %0) {
%2 = alloca i32
%3 = alloca i32
%4 = alloca i32
%5 = alloca %struct.sockaddr_in
%6 = alloca i32
store i32 %0, i32* %3
%7 = load i32, i32* @PF_INET
%8 = load i32, i32* @SOCK_DGRAM
%9 = load i32, i32* @IPPROTO_UDP
%10 = call i32 @socket(i32 %7, i32 %8, i32 %9)
store i32 %10, i32* %4
%11 = load i32, i32* %4
%12 = icmp slt i32 %11, 0
br i1 %12, label %13, label %14
13: ; preds = %1
store i32 -1, i32* %2
br label %32
14: ; preds = %1
%15 = call i32 @memset(%struct.sockaddr_in* %5, i32 0, i32 12)
%16 = load i32, i32* @AF_INET
%17 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %5, i32 0, i32 2
store i32 %16, i32* %17
%18 = load i32, i32* %3
%19 = call i32 @htons(i32 %18)
%20 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %5, i32 0, i32 1
store i32 %19, i32* %20
%21 = load i32, i32* @INADDR_ANY
%22 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %5, i32 0, i32 0
%23 = getelementptr inbounds %struct.TYPE_2__, %struct.TYPE_2__* %22, i32 0, i32 0
store i32 %21, i32* %23
%24 = load i32, i32* %4
%25 = bitcast %struct.sockaddr_in* %5 to %struct.sockaddr*
%26 = call i32 @bind(i32 %24, %struct.sockaddr* %25, i32 12)
store i32 %26, i32* %6
%27 = load i32, i32* %6
%28 = icmp slt i32 %27, 0
br i1 %28, label %29, label %30
29: ; preds = %14
store i32 -2, i32* %2
br label %32
30: ; preds = %14
%31 = load i32, i32* %4
store i32 %31, i32* %2
br label %32
32: ; preds = %30, %29, %13
%33 = load i32, i32* %2
ret i32 %33
}

LLVM IR (-O2):
%struct.sockaddr_in = type { %struct.TYPE_2__, i32, i32 }
%struct.TYPE_2__ = type { i32 }
%struct.sockaddr = type { i32 }
@PF_INET = global i32 0
@SOCK_DGRAM = global i32 0
@IPPROTO_UDP = global i32 0
@AF_INET = global i32 0
@INADDR_ANY = global i32 0
define i32 @udp_socket_listen(i32 %0) {
%2 = alloca %struct.sockaddr_in
%3 = load i32, i32* @PF_INET
%4 = load i32, i32* @SOCK_DGRAM
%5 = load i32, i32* @IPPROTO_UDP
%6 = tail call i32 @socket(i32 %3, i32 %4, i32 %5)
%7 = icmp slt i32 %6, 0
br i1 %7, label %21, label %8
8: ; preds = %1
%9 = bitcast %struct.sockaddr_in* %2 to i8*
%10 = call i32 @memset(%struct.sockaddr_in* %2, i32 0, i32 12)
%11 = load i32, i32* @AF_INET
%12 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %2, i64 0, i32 2
store i32 %11, i32* %12
%13 = call i32 @htons(i32 %0)
%14 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %2, i64 0, i32 1
store i32 %13, i32* %14
%15 = load i32, i32* @INADDR_ANY
%16 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %2, i64 0, i32 0, i32 0
store i32 %15, i32* %16
%17 = bitcast %struct.sockaddr_in* %2 to %struct.sockaddr*
%18 = call i32 @bind(i32 %6, %struct.sockaddr* %17, i32 12)
%19 = icmp slt i32 %18, 0
%20 = select i1 %19, i32 -2, i32 %6
br label %21
21: ; preds = %1, %8
%22 = phi i32 [ %20, %8 ], [ -1, %1 ]
ret i32 %22
}