#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 */
typedef scalar_t__ pid_t;

/* Variables and functions */
int /*<<< orphan*/ execlp(char *, char *, int /*<<< orphan*/ *);
scalar_t__ fork();
int /*<<< orphan*/ fprintf(int /*<<< orphan*/, char *);
int /*<<< orphan*/ printf(char *);
int /*<<< orphan*/ stderr;
int /*<<< orphan*/ wait(int /*<<< orphan*/ *);
int main() {
  pid_t pid;
  pid = fork();
  if (pid < 0) {
    fprintf(stderr, "Fork Failed");
    return 1;
  } else if (pid == 0) {
    execlp("/bin/ls", "ls", NULL);
  } else {
    wait(NULL);
    printf("Child Complete");
  }
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
movl   $0x0,-0x4(%rbp)
mov    $0x0,%al
call   1070 <fork@plt>
mov    %rax,-0x10(%rbp)
cmpq   $0x0,-0x10(%rbp)
jge    1196 <main+0x46>
mov    0x2e64(%rip),%rax
mov    (%rax),%edi
lea    0xe7b(%rip),%rsi
call   1040 <fprintf@plt>
movl   $0x1,-0x4(%rbp)
jmp    11de <main+0x8e>
cmpq   $0x0,-0x10(%rbp)
jne    11bd <main+0x6d>
lea    0xe64(%rip),%rdi
lea    0xe62(%rip),%rsi
xor    %eax,%eax
mov    %eax,%edx
call   1050 <execlp@plt>
jmp    11d2 <main+0x82>
xor    %eax,%eax
mov    %eax,%edi
call   1060 <wait@plt>
lea    0xe47(%rip),%rdi
call   1030 <printf@plt>
jmp    11d7 <main+0x87>
movl   $0x0,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbx
xor    %eax,%eax
call   1070 <fork@plt>
test   %rax,%rax
js     1176 <main+0x26>
je     1192 <main+0x42>
xor    %ebx,%ebx
xor    %edi,%edi
call   1060 <wait@plt>
lea    0xea5(%rip),%rdi
call   1030 <printf@plt>
jmp    11a9 <main+0x59>
mov    0x2e63(%rip),%rax
mov    (%rax),%edi
lea    0xe7a(%rip),%rsi
call   1040 <fprintf@plt>
mov    $0x1,%ebx
jmp    11a9 <main+0x59>
lea    0xe73(%rip),%rdi
lea    0xe71(%rip),%rsi
xor    %ebx,%ebx
xor    %edx,%edx
call   1050 <execlp@plt>
mov    %ebx,%eax
pop    %rbx
ret

LLVM IR (-O0):
@stderr = global i32 0
@.str = [12 x i8] c"Fork Failed\00"
@.str.1 = [8 x i8] c"/bin/ls\00"
@.str.2 = [3 x i8] c"ls\00"
@.str.3 = [15 x i8] c"Child Complete\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca i64
store i32 0, i32* %1
%3 = call i64 (...) @fork()
store i64 %3, i64* %2
%4 = load i64, i64* %2
%5 = icmp slt i64 %4, 0
br i1 %5, label %6, label %9
6: ; preds = %0
%7 = load i32, i32* @stderr
%8 = call i32 @fprintf(i32 %7, i8* getelementptr inbounds ([12 x i8], [12 x i8]* @.str, i64 0, i64 0))
store i32 1, i32* %1
br label %19
9: ; preds = %0
%10 = load i64, i64* %2
%11 = icmp eq i64 %10, 0
br i1 %11, label %12, label %14
12: ; preds = %9
%13 = call i32 @execlp(i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str.1, i64 0, i64 0), i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.2, i64 0, i64 0), i32* null)
br label %17
14: ; preds = %9
%15 = call i32 @wait(i32* null)
%16 = call i32 @printf(i8* getelementptr inbounds ([15 x i8], [15 x i8]* @.str.3, i64 0, i64 0))
br label %17
17: ; preds = %14, %12
br label %18
18: ; preds = %17
store i32 0, i32* %1
br label %19
19: ; preds = %18, %6
%20 = load i32, i32* %1
ret i32 %20
}

LLVM IR (-O2):
@stderr = global i32 0
@.str = [12 x i8] c"Fork Failed\00"
@.str.1 = [8 x i8] c"/bin/ls\00"
@.str.2 = [3 x i8] c"ls\00"
@.str.3 = [15 x i8] c"Child Complete\00"
define i32 @main() {
%1 = tail call i64 (...) @fork()
%2 = icmp slt i64 %1, 0
br i1 %2, label %3, label %6
3: ; preds = %0
%4 = load i32, i32* @stderr
%5 = tail call i32 @fprintf(i32 %4, i8* getelementptr inbounds ([12 x i8], [12 x i8]* @.str, i64 0, i64 0))
br label %13
6: ; preds = %0
%7 = icmp eq i64 %1, 0
br i1 %7, label %8, label %10
8: ; preds = %6
%9 = tail call i32 @execlp(i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str.1, i64 0, i64 0), i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.2, i64 0, i64 0), i32* null)
br label %13
10: ; preds = %6
%11 = tail call i32 @wait(i32* null)
%12 = tail call i32 @printf(i8* dereferenceable(1) getelementptr inbounds ([15 x i8], [15 x i8]* @.str.3, i64 0, i64 0))
br label %13
13: ; preds = %10, %8, %3
%14 = phi i32 [ 1, %3 ], [ 0, %8 ], [ 0, %10 ]
ret i32 %14
}