#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 int /*<<< orphan*/ FILE;

/* Variables and functions */
int /*<<< orphan*/ *fgets(char *, int, int /*<<< orphan*/ *);
int /*<<< orphan*/ *fopen(char *, char *);
int /*<<< orphan*/ printf(char *, char *);
int main() {
  char line[255];
  FILE *fpointer = fopen("config_file.txt", "r");
  int n = 255;
  while (fgets(line, n, fpointer) != NULL)
    printf("%s", line);
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x120,%rsp
movl   $0x0,-0x4(%rbp)
lea    0xeb7(%rip),%rdi
lea    0xec0(%rip),%rsi
call   1050 <fopen@plt>
mov    %rax,-0x118(%rbp)
movl   $0xff,-0x11c(%rbp)
lea    -0x110(%rbp),%rdi
mov    -0x11c(%rbp),%esi
mov    -0x118(%rbp),%rdx
call   1040 <fgets@plt>
cmp    $0x0,%rax
je     11a1 <main+0x71>
lea    -0x110(%rbp),%rsi
lea    0xe7b(%rip),%rdi
call   1030 <printf@plt>
jmp    1166 <main+0x36>
xor    %eax,%eax
add    $0x120,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %r15
push   %r14
push   %rbx
sub    $0x100,%rsp
lea    0xebd(%rip),%rdi
lea    0xec6(%rip),%rsi
call   1050 <fopen@plt>
mov    %rax,%r15
mov    %rsp,%rdi
mov    $0xff,%esi
mov    %rax,%rdx
call   1040 <fgets@plt>
test   %rax,%rax
je     11a0 <main+0x70>
lea    0xea4(%rip),%r14
mov    %rsp,%rbx
cs nopw 0x0(%rax,%rax,1)
nopl   0x0(%rax,%rax,1)
mov    %r14,%rdi
mov    %rbx,%rsi
call   1030 <printf@plt>
mov    %rbx,%rdi
mov    $0xff,%esi
mov    %r15,%rdx
call   1040 <fgets@plt>
test   %rax,%rax
jne    1180 <main+0x50>
xor    %eax,%eax
add    $0x100,%rsp
pop    %rbx
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
@.str = [16 x i8] c"config_file.txt\00"
@.str.1 = [2 x i8] c"r\00"
@.str.2 = [3 x i8] c"%s\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca [255 x i8]
%3 = alloca i32*
%4 = alloca i32
store i32 0, i32* %1
%5 = call i32* @fopen(i8* getelementptr inbounds ([16 x i8], [16 x i8]* @.str, i64 0, i64 0), i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.1, i64 0, i64 0))
store i32* %5, i32** %3
store i32 255, i32* %4
br label %6
6: ; preds = %12, %0
%7 = getelementptr inbounds [255 x i8], [255 x i8]* %2, i64 0, i64 0
%8 = load i32, i32* %4
%9 = load i32*, i32** %3
%10 = call i32* @fgets(i8* %7, i32 %8, i32* %9)
%11 = icmp ne i32* %10, null
br i1 %11, label %12, label %15
12: ; preds = %6
%13 = getelementptr inbounds [255 x i8], [255 x i8]* %2, i64 0, i64 0
%14 = call i32 @printf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.2, i64 0, i64 0), i8* %13)
br label %6
15: ; preds = %6
ret i32 0
}

LLVM IR (-O2):
@.str = [16 x i8] c"config_file.txt\00"
@.str.1 = [2 x i8] c"r\00"
@.str.2 = [3 x i8] c"%s\00"
define i32 @main() {
%1 = alloca [255 x i8]
%2 = getelementptr inbounds [255 x i8], [255 x i8]* %1, i64 0, i64 0
%3 = tail call i32* @fopen(i8* getelementptr inbounds ([16 x i8], [16 x i8]* @.str, i64 0, i64 0), i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.1, i64 0, i64 0))
%4 = call i32* @fgets(i8* %2, i32 255, i32* %3)
%5 = icmp eq i32* %4, null
br i1 %5, label %10, label %6
6: ; preds = %0, %6
%7 = call i32 @printf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.2, i64 0, i64 0), i8* %2)
%8 = call i32* @fgets(i8* %2, i32 255, i32* %3)
%9 = icmp eq i32* %8, null
br i1 %9, label %10, label %6
10: ; preds = %6, %0
ret i32 0
}