#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 dirent {
  char *d_name;
};
typedef int /*<<< orphan*/ DIR;

/* Variables and functions */
int /*<<< orphan*/ closedir(int /*<<< orphan*/ *);
int /*<<< orphan*/ exit(int /*<<< orphan*/);
int /*<<< orphan*/ fprintf(int /*<<< orphan*/, char *);
int /*<<< orphan*/ *opendir(char *);
int /*<<< orphan*/ perror(char *);
int /*<<< orphan*/ printf(char *, char *);
struct dirent *readdir(int /*<<< orphan*/ *);
int /*<<< orphan*/ stderr;
int main(int argc, char *argv[]) {
  DIR *dp;
  struct dirent *dirp;
  if (argc != 2) {
    fprintf(stderr, "usage: ls directory_name\n");
    exit(0);
  }
  if ((dp = opendir(argv[1])) == NULL) {
    perror("Error opening file");
    exit(0);
  }
  while ((dirp = readdir(dp)) != NULL) {
    printf("%s\n", dirp->d_name);
  }
  closedir(dp);
  exit(0);
}


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   $0x2,-0x8(%rbp)
je     11ac <main+0x3c>
mov    0x2e49(%rip),%rax
mov    (%rax),%edi
lea    0xe60(%rip),%rsi
call   1060 <fprintf@plt>
xor    %edi,%edi
call   1090 <exit@plt>
mov    -0x10(%rbp),%rax
mov    0x8(%rax),%rdi
call   1030 <opendir@plt>
mov    %rax,-0x18(%rbp)
cmp    $0x0,%rax
jne    11da <main+0x6a>
lea    0xe4c(%rip),%rdi
call   1080 <perror@plt>
xor    %edi,%edi
call   1090 <exit@plt>
jmp    11df <main+0x6f>
mov    -0x18(%rbp),%rdi
call   1070 <readdir@plt>
mov    %rax,-0x20(%rbp)
cmp    $0x0,%rax
je     120e <main+0x9e>
mov    -0x20(%rbp),%rax
mov    (%rax),%rsi
lea    0xe29(%rip),%rdi
call   1040 <printf@plt>
jmp    11df <main+0x6f>
mov    -0x18(%rbp),%rdi
call   1050 <closedir@plt>
xor    %edi,%edi
call   1090 <exit@plt>

x86 assembly (clang, -O2):
<main>:
push   %r14
push   %rbx
push   %rax
cmp    $0x2,%edi
jne    119a <main+0x2a>
mov    0x8(%rsi),%rdi
call   1030 <opendir@plt>
test   %rax,%rax
jne    11b6 <main+0x46>
lea    0xe8c(%rip),%rdi
call   1080 <perror@plt>
xor    %edi,%edi
call   1090 <exit@plt>
mov    0x2e3f(%rip),%rax
mov    (%rax),%edi
lea    0xe56(%rip),%rsi
call   1060 <fprintf@plt>
xor    %edi,%edi
call   1090 <exit@plt>
mov    %rax,%rbx
mov    %rax,%rdi
call   1070 <readdir@plt>
test   %rax,%rax
je     11e8 <main+0x78>
lea    0xe60(%rip),%r14
nopl   (%rax)
mov    (%rax),%rsi
mov    %r14,%rdi
call   1040 <printf@plt>
mov    %rbx,%rdi
call   1070 <readdir@plt>
test   %rax,%rax
jne    11d0 <main+0x60>
mov    %rbx,%rdi
call   1050 <closedir@plt>
xor    %edi,%edi
call   1090 <exit@plt>

LLVM IR (-O0):
%struct.dirent = type { i8* }
@stderr = global i32 0
@.str = [26 x i8] c"usage: ls directory_name\0A\00"
@.str.1 = [19 x i8] c"Error opening file\00"
@.str.2 = [4 x i8] c"%s\0A\00"
define i32 @main(i32 %0, i8** %1) {
%3 = alloca i32
%4 = alloca i32
%5 = alloca i8**
%6 = alloca i32*
%7 = alloca %struct.dirent*
store i32 0, i32* %3
store i32 %0, i32* %4
store i8** %1, i8*** %5
%8 = load i32, i32* %4
%9 = icmp ne i32 %8, 2
br i1 %9, label %10, label %14
10: ; preds = %2
%11 = load i32, i32* @stderr
%12 = call i32 @fprintf(i32 %11, i8* getelementptr inbounds ([26 x i8], [26 x i8]* @.str, i64 0, i64 0))
%13 = call i32 @exit(i32 0)
unreachable
14: ; preds = %2
%15 = load i8**, i8*** %5
%16 = getelementptr inbounds i8*, i8** %15, i64 1
%17 = load i8*, i8** %16
%18 = call i32* @opendir(i8* %17)
store i32* %18, i32** %6
%19 = icmp eq i32* %18, null
br i1 %19, label %20, label %23
20: ; preds = %14
%21 = call i32 @perror(i8* getelementptr inbounds ([19 x i8], [19 x i8]* @.str.1, i64 0, i64 0))
%22 = call i32 @exit(i32 0)
unreachable
23: ; preds = %14
br label %24
24: ; preds = %28, %23
%25 = load i32*, i32** %6
%26 = call %struct.dirent* @readdir(i32* %25)
store %struct.dirent* %26, %struct.dirent** %7
%27 = icmp ne %struct.dirent* %26, null
br i1 %27, label %28, label %33
28: ; preds = %24
%29 = load %struct.dirent*, %struct.dirent** %7
%30 = getelementptr inbounds %struct.dirent, %struct.dirent* %29, i32 0, i32 0
%31 = load i8*, i8** %30
%32 = call i32 @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.2, i64 0, i64 0), i8* %31)
br label %24
33: ; preds = %24
%34 = load i32*, i32** %6
%35 = call i32 @closedir(i32* %34)
%36 = call i32 @exit(i32 0)
unreachable
}

LLVM IR (-O2):
%struct.dirent = type { i8* }
@stderr = global i32 0
@.str = [26 x i8] c"usage: ls directory_name\0A\00"
@.str.1 = [19 x i8] c"Error opening file\00"
@.str.2 = [4 x i8] c"%s\0A\00"
define i32 @main(i32 %0, i8** nocapture %1) {
%3 = icmp eq i32 %0, 2
br i1 %3, label %8, label %4
4: ; preds = %2
%5 = load i32, i32* @stderr
%6 = tail call i32 @fprintf(i32 %5, i8* getelementptr inbounds ([26 x i8], [26 x i8]* @.str, i64 0, i64 0))
%7 = tail call i32 @exit(i32 0)
unreachable
8: ; preds = %2
%9 = getelementptr inbounds i8*, i8** %1, i64 1
%10 = load i8*, i8** %9
%11 = tail call i32* @opendir(i8* %10)
%12 = icmp eq i32* %11, null
br i1 %12, label %16, label %13
13: ; preds = %8
%14 = tail call %struct.dirent* @readdir(i32* %11)
%15 = icmp eq %struct.dirent* %14, null
br i1 %15, label %26, label %19
16: ; preds = %8
%17 = tail call i32 @perror(i8* getelementptr inbounds ([19 x i8], [19 x i8]* @.str.1, i64 0, i64 0))
%18 = tail call i32 @exit(i32 0)
unreachable
19: ; preds = %13, %19
%20 = phi %struct.dirent* [ %24, %19 ], [ %14, %13 ]
%21 = getelementptr inbounds %struct.dirent, %struct.dirent* %20, i64 0, i32 0
%22 = load i8*, i8** %21
%23 = tail call i32 @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.2, i64 0, i64 0), i8* %22)
%24 = tail call %struct.dirent* @readdir(i32* %11)
%25 = icmp eq %struct.dirent* %24, null
br i1 %25, label %26, label %19
26: ; preds = %19, %13
%27 = tail call i32 @closedir(i32* %11)
%28 = tail call i32 @exit(i32 0)
unreachable
}