#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 /*<<< orphan*/ printf(char *, ...);
int /*<<< orphan*/ scanf(char *, int *);
int main() {
  int n, fib1, fib2, fib3, i;
  printf("Di quanto lunga vuoi la sequenza? ");
  scanf("%d", &n);
  fib1 = 1;
  fib2 = 0;
  fib3 = 0;
  for (i = 0; i < n; i++) {
    printf("%d ", fib1);
    fib3 = fib2;
    fib2 = fib1;
    fib1 = fib2 + fib3;
  }
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
movl   $0x0,-0x4(%rbp)
lea    0xeca(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
lea    0xedf(%rip),%rdi
lea    -0x8(%rbp),%rsi
call   1040 <scanf@plt>
movl   $0x1,-0xc(%rbp)
movl   $0x0,-0x10(%rbp)
movl   $0x0,-0x14(%rbp)
movl   $0x0,-0x18(%rbp)
mov    -0x18(%rbp),%eax
cmp    -0x8(%rbp),%eax
jge    11a9 <main+0x89>
mov    -0xc(%rbp),%esi
lea    0xea7(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
mov    -0x10(%rbp),%eax
mov    %eax,-0x14(%rbp)
mov    -0xc(%rbp),%eax
mov    %eax,-0x10(%rbp)
mov    -0x10(%rbp),%eax
add    -0x14(%rbp),%eax
mov    %eax,-0xc(%rbp)
mov    -0x18(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x18(%rbp)
jmp    1169 <main+0x49>
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbp
push   %r15
push   %r14
push   %rbx
push   %rax
lea    0xed2(%rip),%rdi
xor    %eax,%eax
call   1030 <printf@plt>
lea    0xee7(%rip),%rdi
lea    0x4(%rsp),%rsi
call   1040 <scanf@plt>
cmpl   $0x0,0x4(%rsp)
jle    117f <main+0x5f>
mov    $0x1,%ebp
lea    0xecd(%rip),%r14
xor    %ebx,%ebx
xor    %r15d,%r15d
xchg   %ax,%ax
mov    %r14,%rdi
mov    %ebp,%esi
xor    %eax,%eax
call   1030 <printf@plt>
mov    %r15d,%eax
add    %ebp,%eax
add    $0x1,%ebx
mov    %ebp,%r15d
mov    %eax,%ebp
cmp    0x4(%rsp),%ebx
jl     1160 <main+0x40>
xor    %eax,%eax
add    $0x8,%rsp
pop    %rbx
pop    %r14
pop    %r15
pop    %rbp
ret

LLVM IR (-O0):
@.str = [35 x i8] c"Di quanto lunga vuoi la sequenza? \00"
@.str.1 = [3 x i8] c"%d\00"
@.str.2 = [4 x i8] c"%d \00"
define i32 @main() {
%1 = alloca i32
%2 = alloca i32
%3 = alloca i32
%4 = alloca i32
%5 = alloca i32
%6 = alloca i32
store i32 0, i32* %1
%7 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([35 x i8], [35 x i8]* @.str, i64 0, i64 0))
%8 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i32* %2)
store i32 1, i32* %3
store i32 0, i32* %4
store i32 0, i32* %5
store i32 0, i32* %6
br label %9
9: ; preds = %21, %0
%10 = load i32, i32* %6
%11 = load i32, i32* %2
%12 = icmp slt i32 %10, %11
br i1 %12, label %13, label %24
13: ; preds = %9
%14 = load i32, i32* %3
%15 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.2, i64 0, i64 0), i32 %14)
%16 = load i32, i32* %4
store i32 %16, i32* %5
%17 = load i32, i32* %3
store i32 %17, i32* %4
%18 = load i32, i32* %4
%19 = load i32, i32* %5
%20 = add nsw i32 %18, %19
store i32 %20, i32* %3
br label %21
21: ; preds = %13
%22 = load i32, i32* %6
%23 = add nsw i32 %22, 1
store i32 %23, i32* %6
br label %9
24: ; preds = %9
%25 = load i32, i32* %1
ret i32 %25
}

LLVM IR (-O2):
@.str = [35 x i8] c"Di quanto lunga vuoi la sequenza? \00"
@.str.1 = [3 x i8] c"%d\00"
@.str.2 = [4 x i8] c"%d \00"
define i32 @main() {
%1 = alloca i32
%2 = bitcast i32* %1 to i8*
%3 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([35 x i8], [35 x i8]* @.str, i64 0, i64 0))
%4 = call i32 @scanf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i32* %1)
%5 = load i32, i32* %1
%6 = icmp sgt i32 %5, 0
br i1 %6, label %7, label %16
7: ; preds = %0, %7
%8 = phi i32 [ %13, %7 ], [ 0, %0 ]
%9 = phi i32 [ %10, %7 ], [ 0, %0 ]
%10 = phi i32 [ %12, %7 ], [ 1, %0 ]
%11 = call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([4 x i8], [4 x i8]* @.str.2, i64 0, i64 0), i32 %10)
%12 = add nsw i32 %9, %10
%13 = add nuw nsw i32 %8, 1
%14 = load i32, i32* %1
%15 = icmp slt i32 %13, %14
br i1 %15, label %7, label %16
16: ; preds = %7, %0
ret i32 0
}