#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*/ *fopen(char *, char *);
int /*<<< orphan*/ printf(char *, ...);
int main(int argc, char *argv[]) {
  if (argc != 1) {
    printf("usage %s filename", argv[0]);
  } else {
    FILE *inputfile = fopen(argv[1], "r");
    if (inputfile == 0) {
      printf("Could not open file\n");
    } else {
    }
  }
}


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)
cmpl   $0x1,-0x8(%rbp)
je     115a <main+0x3a>
mov    -0x10(%rbp),%rax
mov    (%rax),%rsi
lea    0xeb2(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
jmp    119a <main+0x7a>
mov    -0x10(%rbp),%rax
mov    0x8(%rax),%rdi
lea    0xea9(%rip),%rsi
call   1040 <fopen@plt>
mov    %rax,-0x18(%rbp)
cmpq   $0x0,-0x18(%rbp)
jne    1190 <main+0x70>
lea    0xe90(%rip),%rdi
mov    $0x0,%al
call   1030 <printf@plt>
jmp    1195 <main+0x75>
jmp    1195 <main+0x75>
jmp    119a <main+0x7a>
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rax
cmp    $0x1,%edi
jne    1159 <main+0x29>
mov    0x8(%rsi),%rdi
lea    0xed1(%rip),%rsi
call   1050 <fopen@plt>
test   %rax,%rax
jne    116a <main+0x3a>
lea    0xec2(%rip),%rdi
call   1030 <puts@plt>
jmp    116a <main+0x3a>
mov    (%rsi),%rsi
lea    0xe9d(%rip),%rdi
xor    %eax,%eax
call   1040 <printf@plt>
xor    %eax,%eax
pop    %rcx
ret

LLVM IR (-O0):
@.str = [18 x i8] c"usage %s filename\00"
@.str.1 = [2 x i8] c"r\00"
@.str.2 = [21 x i8] c"Could not open file\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
%7 = load i32, i32* %4
%8 = icmp ne i32 %7, 1
br i1 %8, label %9, label %14
9: ; preds = %2
%10 = load i8**, i8*** %5
%11 = getelementptr inbounds i8*, i8** %10, i64 0
%12 = load i8*, i8** %11
%13 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([18 x i8], [18 x i8]* @.str, i64 0, i64 0), i8* %12)
br label %25
14: ; preds = %2
%15 = load i8**, i8*** %5
%16 = getelementptr inbounds i8*, i8** %15, i64 1
%17 = load i8*, i8** %16
%18 = call i32* @fopen(i8* %17, i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.1, i64 0, i64 0))
store i32* %18, i32** %6
%19 = load i32*, i32** %6
%20 = icmp eq i32* %19, null
br i1 %20, label %21, label %23
21: ; preds = %14
%22 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([21 x i8], [21 x i8]* @.str.2, i64 0, i64 0))
br label %24
23: ; preds = %14
br label %24
24: ; preds = %23, %21
br label %25
25: ; preds = %24, %9
%26 = load i32, i32* %3
ret i32 %26
}

LLVM IR (-O2):
@.str = [18 x i8] c"usage %s filename\00"
@.str.1 = [2 x i8] c"r\00"
@str = [20 x i8] c"Could not open file\00"
define i32 @main(i32 %0, i8** nocapture %1) {
%3 = icmp eq i32 %0, 1
br i1 %3, label %7, label %4
4: ; preds = %2
%5 = load i8*, i8** %1
%6 = tail call i32 (i8*, ...) @printf(i8* dereferenceable(1) getelementptr inbounds ([18 x i8], [18 x i8]* @.str, i64 0, i64 0), i8* %5)
br label %14
7: ; preds = %2
%8 = getelementptr inbounds i8*, i8** %1, i64 1
%9 = load i8*, i8** %8
%10 = tail call i32* @fopen(i8* %9, i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.1, i64 0, i64 0))
%11 = icmp eq i32* %10, null
br i1 %11, label %12, label %14
12: ; preds = %7
%13 = tail call i32 @puts(i8* dereferenceable(1) getelementptr inbounds ([20 x i8], [20 x i8]* @str, i64 0, i64 0))
br label %14
14: ; preds = %12, %7, %4
ret i32 0
}