#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 */
struct sockaddr_in {
  int /*<<< orphan*/ sin_port;
  int /*<<< orphan*/ sin_addr;
  int /*<<< orphan*/ sin_family;
};
struct hostent {
  int /*<<< orphan*/ h_length;
  scalar_t__ h_addr;
};

/* Variables and functions */
int /*<<< orphan*/ AF_INET;
int /*<<< orphan*/ SOCK_DGRAM;
int /*<<< orphan*/ atoi(char *);
int /*<<< orphan*/ bcopy(char *, char *, int /*<<< orphan*/);
int /*<<< orphan*/ bzero(char *, int);
int /*<<< orphan*/ error(char *);
int /*<<< orphan*/ exit(int);
int /*<<< orphan*/ fgets(char *, int, int /*<<< orphan*/);
struct hostent *gethostbyname(char *);
int /*<<< orphan*/ htons(int /*<<< orphan*/);
int /*<<< orphan*/ printf(char *);
int recvfrom(int, char *, int, int /*<<< orphan*/, struct sockaddr_in *, int *);
int sendto(int, char *, int /*<<< orphan*/, int /*<<< orphan*/,
           struct sockaddr_in *, int);
int socket(int /*<<< orphan*/, int /*<<< orphan*/, int /*<<< orphan*/);
int /*<<< orphan*/ stdin;
int /*<<< orphan*/ strlen(char *);
int /*<<< orphan*/ write(int, char *, int);
int main(int argc, char *argv[]) {
  int sock, length, fromlen, n;
  char buffer[256];
  struct sockaddr_in server, from;
  struct hostent *hp;
  if (argc != 3) {
    printf("Error: usage server port\n");
    exit(1);
  }
  sock = socket(AF_INET, SOCK_DGRAM, 0);
  if (sock < 0) {
    error("Error while opening the socket ...");
  }
  length = sizeof(struct sockaddr_in);
  server.sin_family = AF_INET;
  hp = gethostbyname(argv[1]);
  if (hp == 0) {
    error("Error: unknown host");
  }
  bcopy((char *)hp->h_addr, (char *)&server.sin_addr, hp->h_length);
  server.sin_port = htons(atoi(argv[2]));
  bzero(buffer, 256);
  fgets(buffer, 255, stdin);
  n = sendto(sock, buffer, strlen(buffer), 0, &server, length);
  if (n < 0) {
    error("Error while trying to send to the socket ...");
  }
  bzero(buffer, 256);
  n = recvfrom(sock, buffer, 256, 0, &from, &length);
  if (n < 0) {
    error("Error while reading from the socket");
  }
  write(1, "Received an incoming datagram ( ACK ):", 38);
  write(1, buffer, n);
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x160,%rsp
movl   $0x0,-0x4(%rbp)
mov    %edi,-0x8(%rbp)
mov    %rsi,-0x10(%rbp)
cmpl   $0x3,-0x8(%rbp)
je     1219 <main+0x39>
lea    0xdf6(%rip),%rdi
call   1060 <printf@plt>
mov    $0x1,%edi
call   10f0 <exit@plt>
mov    0x2dc8(%rip),%rax
mov    (%rax),%edi
mov    0x2daf(%rip),%rax
mov    (%rax),%esi
xor    %edx,%edx
call   1100 <socket@plt>
mov    %eax,-0x14(%rbp)
cmpl   $0x0,-0x14(%rbp)
jge    124b <main+0x6b>
lea    0xdd4(%rip),%rdi
call   10c0 <error@plt>
movl   $0xc,-0x18(%rbp)
mov    0x2d8f(%rip),%rax
mov    (%rax),%eax
mov    %eax,-0x128(%rbp)
mov    -0x10(%rbp),%rax
mov    0x8(%rax),%rdi
call   1090 <gethostbyname@plt>
mov    %rax,-0x148(%rbp)
cmpq   $0x0,-0x148(%rbp)
jne    128f <main+0xaf>
lea    0xdb3(%rip),%rdi
call   10c0 <error@plt>
mov    -0x148(%rbp),%rax
mov    0x8(%rax),%rdi
lea    -0x130(%rbp),%rsi
add    $0x4,%rsi
mov    -0x148(%rbp),%rax
mov    (%rax),%edx
call   10b0 <bcopy@plt>
mov    -0x10(%rbp),%rax
mov    0x10(%rax),%rdi
call   10e0 <atoi@plt>
mov    %eax,%edi
call   1050 <htons@plt>
mov    %eax,-0x130(%rbp)
lea    -0x120(%rbp),%rdi
mov    $0x100,%esi
call   10d0 <bzero@plt>
lea    -0x120(%rbp),%rdi
mov    0x2cf4(%rip),%rax
mov    (%rax),%edx
mov    $0xff,%esi
call   1080 <fgets@plt>
mov    -0x14(%rbp),%eax
mov    %eax,-0x154(%rbp)
lea    -0x120(%rbp),%rax
mov    %rax,-0x150(%rbp)
lea    -0x120(%rbp),%rdi
call   1040 <strlen@plt>
mov    -0x154(%rbp),%edi
mov    -0x150(%rbp),%rsi
mov    %eax,%edx
mov    -0x18(%rbp),%r9d
xor    %ecx,%ecx
lea    -0x130(%rbp),%r8
call   1070 <sendto@plt>
mov    %eax,-0x20(%rbp)
cmpl   $0x0,-0x20(%rbp)
jge    1355 <main+0x175>
lea    0xd01(%rip),%rdi
call   10c0 <error@plt>
lea    -0x120(%rbp),%rdi
mov    $0x100,%esi
call   10d0 <bzero@plt>
mov    -0x14(%rbp),%edi
lea    -0x120(%rbp),%rsi
mov    $0x100,%edx
xor    %ecx,%ecx
lea    -0x140(%rbp),%r8
lea    -0x18(%rbp),%r9
call   10a0 <recvfrom@plt>
mov    %eax,-0x20(%rbp)
cmpl   $0x0,-0x20(%rbp)
jge    13a0 <main+0x1c0>
lea    0xce3(%rip),%rdi
call   10c0 <error@plt>
mov    $0x1,%edi
lea    0xcf6(%rip),%rsi
mov    $0x26,%edx
call   1030 <write@plt>
lea    -0x120(%rbp),%rsi
mov    -0x20(%rbp),%edx
mov    $0x1,%edi
call   1030 <write@plt>
mov    -0x4(%rbp),%eax
add    $0x160,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbp
push   %r14
push   %rbx
sub    $0x130,%rsp
cmp    $0x3,%edi
jne    1344 <main+0x164>
mov    %rsi,%rbx
mov    0x2dea(%rip),%rbp
mov    0x0(%rbp),%edi
mov    0x2dd0(%rip),%rax
mov    (%rax),%esi
xor    %edx,%edx
call   1100 <socket@plt>
mov    %eax,%r14d
test   %eax,%eax
jns    1224 <main+0x44>
lea    0xde1(%rip),%rdi
call   10c0 <error@plt>
movl   $0xc,0xc(%rsp)
mov    0x0(%rbp),%eax
mov    %eax,0x18(%rsp)
mov    0x8(%rbx),%rdi
call   1090 <gethostbyname@plt>
mov    %rax,%rbp
test   %rax,%rax
jne    1250 <main+0x70>
lea    0xdd8(%rip),%rdi
call   10c0 <error@plt>
mov    0x8(%rbp),%rsi
lea    0x14(%rsp),%rdi
mov    0x0(%rbp),%edx
call   10b0 <memmove@plt>
mov    0x10(%rbx),%rdi
call   10e0 <atoi@plt>
mov    %eax,%edi
call   1060 <htons@plt>
mov    %eax,0x10(%rsp)
lea    0x30(%rsp),%rbx
mov    %rbx,%rdi
mov    $0x100,%esi
call   10d0 <bzero@plt>
mov    0x2d52(%rip),%rax
mov    (%rax),%edx
mov    %rbx,%rdi
mov    $0xff,%esi
call   1080 <fgets@plt>
mov    %rbx,%rdi
call   1050 <strlen@plt>
lea    0x10(%rsp),%r8
mov    %r14d,%edi
mov    %rbx,%rsi
mov    %eax,%edx
xor    %ecx,%ecx
mov    $0xc,%r9d
call   1070 <sendto@plt>
test   %eax,%eax
jns    12cf <main+0xef>
lea    0xd6d(%rip),%rdi
call   10c0 <error@plt>
lea    0x30(%rsp),%rbx
mov    %rbx,%rdi
mov    $0x100,%esi
call   10d0 <bzero@plt>
lea    0x20(%rsp),%r8
lea    0xc(%rsp),%r9
mov    %r14d,%edi
mov    %rbx,%rsi
mov    $0x100,%edx
xor    %ecx,%ecx
call   10a0 <recvfrom@plt>
mov    %eax,%ebx
test   %eax,%eax
jns    130f <main+0x12f>
lea    0xd5a(%rip),%rdi
call   10c0 <error@plt>
lea    0xd72(%rip),%rsi
mov    $0x1,%edi
mov    $0x26,%edx
call   1040 <write@plt>
lea    0x30(%rsp),%rsi
mov    $0x1,%edi
mov    %ebx,%edx
call   1040 <write@plt>
xor    %eax,%eax
add    $0x130,%rsp
pop    %rbx
pop    %r14
pop    %rbp
ret
lea    0xd64(%rip),%rdi
call   1030 <puts@plt>
mov    $0x1,%edi
call   10f0 <exit@plt>

LLVM IR (-O0):
%struct.sockaddr_in = type { i32, i32, i32 }
%struct.hostent = type { i32, i64 }
@.str = [26 x i8] c"Error: usage server port\0A\00"
@AF_INET = global i32 0
@SOCK_DGRAM = global i32 0
@.str.1 = [35 x i8] c"Error while opening the socket ...\00"
@.str.2 = [20 x i8] c"Error: unknown host\00"
@stdin = global i32 0
@.str.3 = [45 x i8] c"Error while trying to send to the socket ...\00"
@.str.4 = [36 x i8] c"Error while reading from the socket\00"
@.str.5 = [39 x i8] c"Received an incoming datagram ( ACK ):\00"
define i32 @main(i32 %0, i8** %1) {
%3 = alloca i32
%4 = alloca i32
%5 = alloca i8**
%6 = alloca i32
%7 = alloca i32
%8 = alloca i32
%9 = alloca i32
%10 = alloca [256 x i8]
%11 = alloca %struct.sockaddr_in
%12 = alloca %struct.sockaddr_in
%13 = alloca %struct.hostent*
store i32 0, i32* %3
store i32 %0, i32* %4
store i8** %1, i8*** %5
%14 = load i32, i32* %4
%15 = icmp ne i32 %14, 3
br i1 %15, label %16, label %19
16: ; preds = %2
%17 = call i32 @printf(i8* getelementptr inbounds ([26 x i8], [26 x i8]* @.str, i64 0, i64 0))
%18 = call i32 @exit(i32 1)
unreachable
19: ; preds = %2
%20 = load i32, i32* @AF_INET
%21 = load i32, i32* @SOCK_DGRAM
%22 = call i32 @socket(i32 %20, i32 %21, i32 0)
store i32 %22, i32* %6
%23 = load i32, i32* %6
%24 = icmp slt i32 %23, 0
br i1 %24, label %25, label %27
25: ; preds = %19
%26 = call i32 @error(i8* getelementptr inbounds ([35 x i8], [35 x i8]* @.str.1, i64 0, i64 0))
br label %27
27: ; preds = %25, %19
store i32 12, i32* %7
%28 = load i32, i32* @AF_INET
%29 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %11, i32 0, i32 2
store i32 %28, i32* %29
%30 = load i8**, i8*** %5
%31 = getelementptr inbounds i8*, i8** %30, i64 1
%32 = load i8*, i8** %31
%33 = call %struct.hostent* @gethostbyname(i8* %32)
store %struct.hostent* %33, %struct.hostent** %13
%34 = load %struct.hostent*, %struct.hostent** %13
%35 = icmp eq %struct.hostent* %34, null
br i1 %35, label %36, label %38
36: ; preds = %27
%37 = call i32 @error(i8* getelementptr inbounds ([20 x i8], [20 x i8]* @.str.2, i64 0, i64 0))
br label %38
38: ; preds = %36, %27
%39 = load %struct.hostent*, %struct.hostent** %13
%40 = getelementptr inbounds %struct.hostent, %struct.hostent* %39, i32 0, i32 1
%41 = load i64, i64* %40
%42 = inttoptr i64 %41 to i8*
%43 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %11, i32 0, i32 1
%44 = bitcast i32* %43 to i8*
%45 = load %struct.hostent*, %struct.hostent** %13
%46 = getelementptr inbounds %struct.hostent, %struct.hostent* %45, i32 0, i32 0
%47 = load i32, i32* %46
%48 = call i32 @bcopy(i8* %42, i8* %44, i32 %47)
%49 = load i8**, i8*** %5
%50 = getelementptr inbounds i8*, i8** %49, i64 2
%51 = load i8*, i8** %50
%52 = call i32 @atoi(i8* %51)
%53 = call i32 @htons(i32 %52)
%54 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %11, i32 0, i32 0
store i32 %53, i32* %54
%55 = getelementptr inbounds [256 x i8], [256 x i8]* %10, i64 0, i64 0
%56 = call i32 @bzero(i8* %55, i32 256)
%57 = getelementptr inbounds [256 x i8], [256 x i8]* %10, i64 0, i64 0
%58 = load i32, i32* @stdin
%59 = call i32 @fgets(i8* %57, i32 255, i32 %58)
%60 = load i32, i32* %6
%61 = getelementptr inbounds [256 x i8], [256 x i8]* %10, i64 0, i64 0
%62 = getelementptr inbounds [256 x i8], [256 x i8]* %10, i64 0, i64 0
%63 = call i32 @strlen(i8* %62)
%64 = load i32, i32* %7
%65 = call i32 @sendto(i32 %60, i8* %61, i32 %63, i32 0, %struct.sockaddr_in* %11, i32 %64)
store i32 %65, i32* %9
%66 = load i32, i32* %9
%67 = icmp slt i32 %66, 0
br i1 %67, label %68, label %70
68: ; preds = %38
%69 = call i32 @error(i8* getelementptr inbounds ([45 x i8], [45 x i8]* @.str.3, i64 0, i64 0))
br label %70
70: ; preds = %68, %38
%71 = getelementptr inbounds [256 x i8], [256 x i8]* %10, i64 0, i64 0
%72 = call i32 @bzero(i8* %71, i32 256)
%73 = load i32, i32* %6
%74 = getelementptr inbounds [256 x i8], [256 x i8]* %10, i64 0, i64 0
%75 = call i32 @recvfrom(i32 %73, i8* %74, i32 256, i32 0, %struct.sockaddr_in* %12, i32* %7)
store i32 %75, i32* %9
%76 = load i32, i32* %9
%77 = icmp slt i32 %76, 0
br i1 %77, label %78, label %80
78: ; preds = %70
%79 = call i32 @error(i8* getelementptr inbounds ([36 x i8], [36 x i8]* @.str.4, i64 0, i64 0))
br label %80
80: ; preds = %78, %70
%81 = call i32 @write(i32 1, i8* getelementptr inbounds ([39 x i8], [39 x i8]* @.str.5, i64 0, i64 0), i32 38)
%82 = getelementptr inbounds [256 x i8], [256 x i8]* %10, i64 0, i64 0
%83 = load i32, i32* %9
%84 = call i32 @write(i32 1, i8* %82, i32 %83)
%85 = load i32, i32* %3
ret i32 %85
}

LLVM IR (-O2):
%struct.sockaddr_in = type { i32, i32, i32 }
%struct.hostent = type { i32, i64 }
@AF_INET = global i32 0
@SOCK_DGRAM = global i32 0
@.str.1 = [35 x i8] c"Error while opening the socket ...\00"
@.str.2 = [20 x i8] c"Error: unknown host\00"
@stdin = global i32 0
@.str.3 = [45 x i8] c"Error while trying to send to the socket ...\00"
@.str.4 = [36 x i8] c"Error while reading from the socket\00"
@.str.5 = [39 x i8] c"Received an incoming datagram ( ACK ):\00"
@str = [25 x i8] c"Error: usage server port\00"
define i32 @main(i32 %0, i8** nocapture %1) {
%3 = alloca i32
%4 = alloca [256 x i8]
%5 = alloca %struct.sockaddr_in
%6 = alloca %struct.sockaddr_in
%7 = bitcast i32* %3 to i8*
%8 = getelementptr inbounds [256 x i8], [256 x i8]* %4, i64 0, i64 0
%9 = bitcast %struct.sockaddr_in* %5 to i8*
%10 = bitcast %struct.sockaddr_in* %6 to i8*
%11 = icmp eq i32 %0, 3
br i1 %11, label %15, label %12
12: ; preds = %2
%13 = tail call i32 @puts(i8* dereferenceable(1) getelementptr inbounds ([25 x i8], [25 x i8]* @str, i64 0, i64 0))
%14 = tail call i32 @exit(i32 1)
unreachable
15: ; preds = %2
%16 = load i32, i32* @AF_INET
%17 = load i32, i32* @SOCK_DGRAM
%18 = tail call i32 @socket(i32 %16, i32 %17, i32 0)
%19 = icmp slt i32 %18, 0
br i1 %19, label %20, label %22
20: ; preds = %15
%21 = tail call i32 @error(i8* getelementptr inbounds ([35 x i8], [35 x i8]* @.str.1, i64 0, i64 0))
br label %22
22: ; preds = %20, %15
store i32 12, i32* %3
%23 = load i32, i32* @AF_INET
%24 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %5, i64 0, i32 2
store i32 %23, i32* %24
%25 = getelementptr inbounds i8*, i8** %1, i64 1
%26 = load i8*, i8** %25
%27 = tail call %struct.hostent* @gethostbyname(i8* %26)
%28 = icmp eq %struct.hostent* %27, null
br i1 %28, label %29, label %31
29: ; preds = %22
%30 = tail call i32 @error(i8* getelementptr inbounds ([20 x i8], [20 x i8]* @.str.2, i64 0, i64 0))
br label %31
31: ; preds = %29, %22
%32 = getelementptr inbounds %struct.hostent, %struct.hostent* %27, i64 0, i32 1
%33 = load i64, i64* %32
%34 = inttoptr i64 %33 to i8*
%35 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %5, i64 0, i32 1
%36 = bitcast i32* %35 to i8*
%37 = getelementptr inbounds %struct.hostent, %struct.hostent* %27, i64 0, i32 0
%38 = load i32, i32* %37
%39 = getelementptr inbounds i8*, i8** %1, i64 2
%40 = load i8*, i8** %39
%41 = tail call i32 @atoi(i8* %40)
%42 = tail call i32 @htons(i32 %41)
%43 = getelementptr inbounds %struct.sockaddr_in, %struct.sockaddr_in* %5, i64 0, i32 0
store i32 %42, i32* %43
%44 = call i32 @bzero(i8* %8, i32 256)
%45 = load i32, i32* @stdin
%46 = call i32 @fgets(i8* %8, i32 255, i32 %45)
%47 = call i32 @strlen(i8* %8)
%48 = call i32 @sendto(i32 %18, i8* %8, i32 %47, i32 0, %struct.sockaddr_in* %5, i32 12)
%49 = icmp slt i32 %48, 0
br i1 %49, label %50, label %52
50: ; preds = %31
%51 = call i32 @error(i8* getelementptr inbounds ([45 x i8], [45 x i8]* @.str.3, i64 0, i64 0))
br label %52
52: ; preds = %50, %31
%53 = call i32 @bzero(i8* %8, i32 256)
%54 = call i32 @recvfrom(i32 %18, i8* %8, i32 256, i32 0, %struct.sockaddr_in* %6, i32* %3)
%55 = icmp slt i32 %54, 0
br i1 %55, label %56, label %58
56: ; preds = %52
%57 = call i32 @error(i8* getelementptr inbounds ([36 x i8], [36 x i8]* @.str.4, i64 0, i64 0))
br label %58
58: ; preds = %56, %52
%59 = call i32 @write(i32 1, i8* getelementptr inbounds ([39 x i8], [39 x i8]* @.str.5, i64 0, i64 0), i32 38)
%60 = call i32 @write(i32 1, i8* %8, i32 %54)
ret i32 0
}