#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 atoi(char *);
int fib(int, int, int);
int /*<<< orphan*/ printf(char *, ...);
int main(int argc, char **argv) {
  int n = 0;
  if (argc != 2) {
    printf("\nUsage is bruijn <number>\n To calculate nth fibonacci number\n");
  } else {
    n = atoi(argv[1]);
    printf("\n%dth Fibonacci number is %d\n", n, fib(n, 1, 1));
  }
  return 1;
}


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)
movl   $0x0,-0x14(%rbp)
cmpl   $0x2,-0x8(%rbp)
je     116a <main+0x3a>
lea    0xea2(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
jmp    11a2 <main+0x72>
mov    -0x10(%rbp),%rax
mov    0x8(%rax),%rdi
call   1050 <atoi@plt>
mov    %eax,-0x14(%rbp)
mov    -0x14(%rbp),%eax
mov    %eax,-0x18(%rbp)
mov    -0x14(%rbp),%edi
mov    $0x1,%edx
mov    %edx,%esi
call   1040 <fib@plt>
mov    -0x18(%rbp),%esi
mov    %eax,%edx
lea    0xea3(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    $0x1,%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbx
cmp    $0x2,%edi
jne    1176 <main+0x36>
mov    0x8(%rsi),%rdi
call   1060 <atoi@plt>
mov    %eax,%ebx
mov    %eax,%edi
mov    $0x1,%esi
mov    $0x1,%edx
call   1050 <fib@plt>
lea    0xe97(%rip),%rdi
mov    %ebx,%esi
mov    %eax,%edx
xor    %eax,%eax
call   1040 <printf@plt>
jmp    1182 <main+0x42>
lea    0xea1(%rip),%rdi
call   1030 <puts@plt>
mov    $0x1,%eax
pop    %rbx
ret

LLVM IR (-O0):
@.str = [62 x i8] c"\0AUsage is bruijn <number>\0A To calculate nth fibonacci number\0A\00"
@.str.1 = [30 x i8] c"\0A%dth Fibonacci number is %d\0A\00"
define i32 @main(i32 %0, i8** %1) {
%3 = alloca i32
%4 = alloca i32
%5 = alloca i8**
%6 = alloca i32
store i32 0, i32* %3
store i32 %0, i32* %4
store i8** %1, i8*** %5
store i32 0, i32* %6
%7 = load i32, i32* %4
%8 = icmp ne i32 %7, 2
br i1 %8, label %9, label %11
9: ; preds = %2
%10 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([62 x i8], [62 x i8]* @.str, i64 0, i64 0))
br label %20
11: ; preds = %2
%12 = load i8**, i8*** %5
%13 = getelementptr inbounds i8*, i8** %12, i64 1
%14 = load i8*, i8** %13
%15 = call i32 @atoi(i8* %14)
store i32 %15, i32* %6
%16 = load i32, i32* %6
%17 = load i32, i32* %6
%18 = call i32 @fib(i32 %17, i32 1, i32 1)
%19 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([30 x i8], [30 x i8]* @.str.1, i64 0, i64 0), i32 %16, i32 %18)
br label %20
20: ; preds = %11, %9
ret i32 1
}

LLVM IR (-O2):
@.str.1 = [30 x i8] c"\0A%dth Fibonacci number is %d\0A\00"
@str = [61 x i8] c"\0AUsage is bruijn <number>\0A To calculate nth fibonacci number\00"
define i32 @main(i32 %0, i8** nocapture %1) {
%3 = icmp eq i32 %0, 2
br i1 %3, label %6, label %4
4: ; preds = %2
%5 = tail call i32 @puts(i8* dereferenceable(1) getelementptr inbounds ([61 x i8], [61 x i8]* @str, i64 0, i64 0))
br label %12
6: ; preds = %2
%7 = getelementptr inbounds i8*, i8** %1, i64 1
%8 = load i8*, i8** %7
%9 = tail call i32 @atoi(i8* %8)
%10 = tail call i32 @fib(i32 %9, i32 1, i32 1)
%11 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([30 x i8], [30 x i8]* @.str.1, i64 0, i64 0), i32 %9, i32 %10)
br label %12
12: ; preds = %6, %4
ret i32 1
}