#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 */

/* Variables and functions */
int omp_get_num_threads();
int omp_get_thread_num();
int /*<<< orphan*/ printf(char *, int);
int main(int argc, char *argv[]) {
  int th_id, nthreads;
#pragma omp parallel private(th_id)
  {
    th_id = omp_get_thread_num();
    printf("Hello World! ... from thread %d\n", th_id);
#pragma omp barrier
    if (th_id == 0) {
      nthreads = omp_get_num_threads();
      printf("There are %d threads\n", nthreads);
    }
  }
  return 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)
mov    $0x0,%al
call   1030 <omp_get_thread_num@plt>
mov    %eax,-0x14(%rbp)
mov    -0x14(%rbp),%esi
lea    0xea6(%rip),%rdi
call   1040 <printf@plt>
cmpl   $0x0,-0x14(%rbp)
jne    1182 <main+0x52>
mov    $0x0,%al
call   1050 <omp_get_num_threads@plt>
mov    %eax,-0x18(%rbp)
mov    -0x18(%rbp),%esi
lea    0xea4(%rip),%rdi
call   1040 <printf@plt>
xor    %eax,%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbx
xor    %eax,%eax
call   1030 <omp_get_thread_num@plt>
mov    %eax,%ebx
lea    0xebf(%rip),%rdi
mov    %eax,%esi
call   1040 <printf@plt>
test   %ebx,%ebx
jne    1161 <main+0x31>
xor    %eax,%eax
call   1050 <omp_get_num_threads@plt>
lea    0xec7(%rip),%rdi
mov    %eax,%esi
call   1040 <printf@plt>
xor    %eax,%eax
pop    %rbx
ret

LLVM IR (-O0):
@.str = [33 x i8] c"Hello World! ... from thread %d\0A\00"
@.str.1 = [22 x i8] c"There are %d threads\0A\00"
define i32 @main(i32 %0, i8** %1) {
%3 = alloca i32
%4 = alloca i32
%5 = alloca i8**
%6 = alloca i32
%7 = alloca i32
store i32 0, i32* %3
store i32 %0, i32* %4
store i8** %1, i8*** %5
%8 = call i32 (...) @omp_get_thread_num()
store i32 %8, i32* %6
%9 = load i32, i32* %6
%10 = call i32 @printf(i8* getelementptr inbounds ([33 x i8], [33 x i8]* @.str, i64 0, i64 0), i32 %9)
%11 = load i32, i32* %6
%12 = icmp eq i32 %11, 0
br i1 %12, label %13, label %17
13: ; preds = %2
%14 = call i32 (...) @omp_get_num_threads()
store i32 %14, i32* %7
%15 = load i32, i32* %7
%16 = call i32 @printf(i8* getelementptr inbounds ([22 x i8], [22 x i8]* @.str.1, i64 0, i64 0), i32 %15)
br label %17
17: ; preds = %13, %2
ret i32 0
}

LLVM IR (-O2):
@.str = [33 x i8] c"Hello World! ... from thread %d\0A\00"
@.str.1 = [22 x i8] c"There are %d threads\0A\00"
define i32 @main(i32 %0, i8** nocapture readnone %1) {
%3 = tail call i32 (...) @omp_get_thread_num()
%4 = tail call i32 @printf(i8* getelementptr inbounds ([33 x i8], [33 x i8]* @.str, i64 0, i64 0), i32 %3)
%5 = icmp eq i32 %3, 0
br i1 %5, label %6, label %9
6: ; preds = %2
%7 = tail call i32 (...) @omp_get_num_threads()
%8 = tail call i32 @printf(i8* getelementptr inbounds ([22 x i8], [22 x i8]* @.str.1, i64 0, i64 0), i32 %7)
br label %9
9: ; preds = %6, %2
ret i32 0
}