#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*/ fclose(int /*<<< orphan*/ *);
int /*<<< orphan*/ *fopen(char const *, char *);
int /*<<< orphan*/ fprintf(int /*<<< orphan*/, char *, char const *);
int /*<<< orphan*/ stderr;
int file_exists(const char *filename) {
  FILE *fd = fopen(filename, "r");
  if (NULL == fd) {
    fprintf(stderr, "ERROR: File '%s' does not exist\n", filename);
    return 0;
  }
  fclose(fd);
  return 1;
}


x86 assembly (clang, -O0):
<file_exists>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
mov    %rdi,-0x10(%rbp)
mov    -0x10(%rbp),%rdi
lea    0xeb9(%rip),%rsi
call   1050 <fopen@plt>
mov    %rax,-0x18(%rbp)
xor    %eax,%eax
cmp    -0x18(%rbp),%rax
jne    1181 <file_exists+0x51>
mov    0x2e7d(%rip),%rax
mov    (%rax),%edi
mov    -0x10(%rbp),%rdx
lea    0xe92(%rip),%rsi
call   1040 <fprintf@plt>
movl   $0x0,-0x4(%rbp)
jmp    1191 <file_exists+0x61>
mov    -0x18(%rbp),%rdi
call   1030 <fclose@plt>
movl   $0x1,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<file_exists>:
push   %rbx
mov    %rdi,%rbx
lea    0xec5(%rip),%rsi
call   1050 <fopen@plt>
test   %rax,%rax
je     1154 <file_exists+0x24>
mov    %rax,%rdi
call   1030 <fclose@plt>
mov    $0x1,%eax
pop    %rbx
ret
mov    0x2e85(%rip),%rax
mov    (%rax),%edi
lea    0xe9e(%rip),%rsi
mov    %rbx,%rdx
call   1040 <fprintf@plt>
xor    %eax,%eax
pop    %rbx
ret

LLVM IR (-O0):
@.str = [2 x i8] c"r\00"
@stderr = global i32 0
@.str.1 = [33 x i8] c"ERROR: File '%s' does not exist\0A\00"
define i32 @file_exists(i8* %0) {
%2 = alloca i32
%3 = alloca i8*
%4 = alloca i32*
store i8* %0, i8** %3
%5 = load i8*, i8** %3
%6 = call i32* @fopen(i8* %5, i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str, i64 0, i64 0))
store i32* %6, i32** %4
%7 = load i32*, i32** %4
%8 = icmp eq i32* null, %7
br i1 %8, label %9, label %13
9: ; preds = %1
%10 = load i32, i32* @stderr
%11 = load i8*, i8** %3
%12 = call i32 @fprintf(i32 %10, i8* getelementptr inbounds ([33 x i8], [33 x i8]* @.str.1, i64 0, i64 0), i8* %11)
store i32 0, i32* %2
br label %16
13: ; preds = %1
%14 = load i32*, i32** %4
%15 = call i32 @fclose(i32* %14)
store i32 1, i32* %2
br label %16
16: ; preds = %13, %9
%17 = load i32, i32* %2
ret i32 %17
}

LLVM IR (-O2):
@.str = [2 x i8] c"r\00"
@stderr = global i32 0
@.str.1 = [33 x i8] c"ERROR: File '%s' does not exist\0A\00"
define i32 @file_exists(i8* %0) {
%2 = tail call i32* @fopen(i8* %0, i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str, i64 0, i64 0))
%3 = icmp eq i32* %2, null
br i1 %3, label %4, label %7
4: ; preds = %1
%5 = load i32, i32* @stderr
%6 = tail call i32 @fprintf(i32 %5, i8* getelementptr inbounds ([33 x i8], [33 x i8]* @.str.1, i64 0, i64 0), i8* %0)
br label %9
7: ; preds = %1
%8 = tail call i32 @fclose(i32* %2)
br label %9
9: ; preds = %7, %4
%10 = phi i32 [ 0, %4 ], [ 1, %7 ]
ret i32 %10
}