#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*/ O_RDONLY;
int /*<<< orphan*/ close(int);
int open(char *, int /*<<< orphan*/);
int /*<<< orphan*/ perror(char *);
int /*<<< orphan*/ printf(char *, int);
int main(int argc, char *argv[]) {
  int fd = open("open.c", O_RDONLY);
  if (fd < 0) {
    perror("open failed");
    goto err_open;
  }
  printf("fd = %d\n", fd);
  close(fd);
  return 0;
err_open:
  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)
mov    0x2e8b(%rip),%rax
mov    (%rax),%esi
lea    0xe9a(%rip),%rdi
call   1050 <open@plt>
mov    %eax,-0x14(%rbp)
cmpl   $0x0,-0x14(%rbp)
jge    1189 <main+0x49>
lea    0xe88(%rip),%rdi
call   1060 <perror@plt>
jmp    11ac <main+0x6c>
mov    -0x14(%rbp),%esi
lea    0xe80(%rip),%rdi
call   1030 <printf@plt>
mov    -0x14(%rbp),%edi
call   1040 <close@plt>
movl   $0x0,-0x4(%rbp)
jmp    11b3 <main+0x73>
movl   $0xffffffff,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbx
mov    0x2ea0(%rip),%rax
mov    (%rax),%esi
lea    0xeaf(%rip),%rdi
call   1050 <open@plt>
test   %eax,%eax
js     1175 <main+0x35>
mov    %eax,%ebx
lea    0xeb0(%rip),%rdi
mov    %eax,%esi
call   1030 <printf@plt>
mov    %ebx,%edi
call   1040 <close@plt>
xor    %eax,%eax
pop    %rbx
ret
lea    0xe8b(%rip),%rdi
call   1060 <perror@plt>
mov    $0xffffffff,%eax
pop    %rbx
ret

LLVM IR (-O0):
@.str = [7 x i8] c"open.c\00"
@O_RDONLY = global i32 0
@.str.1 = [12 x i8] c"open failed\00"
@.str.2 = [9 x i8] c"fd = %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
%7 = load i32, i32* @O_RDONLY
%8 = call i32 @open(i8* getelementptr inbounds ([7 x i8], [7 x i8]* @.str, i64 0, i64 0), i32 %7)
store i32 %8, i32* %6
%9 = load i32, i32* %6
%10 = icmp slt i32 %9, 0
br i1 %10, label %11, label %13
11: ; preds = %2
%12 = call i32 @perror(i8* getelementptr inbounds ([12 x i8], [12 x i8]* @.str.1, i64 0, i64 0))
br label %18
13: ; preds = %2
%14 = load i32, i32* %6
%15 = call i32 @printf(i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.2, i64 0, i64 0), i32 %14)
%16 = load i32, i32* %6
%17 = call i32 @close(i32 %16)
store i32 0, i32* %3
br label %19
18: ; preds = %11
store i32 -1, i32* %3
br label %19
19: ; preds = %18, %13
%20 = load i32, i32* %3
ret i32 %20
}

LLVM IR (-O2):
@.str = [7 x i8] c"open.c\00"
@O_RDONLY = global i32 0
@.str.1 = [12 x i8] c"open failed\00"
@.str.2 = [9 x i8] c"fd = %d\0A\00"
define i32 @main(i32 %0, i8** nocapture readnone %1) {
%3 = load i32, i32* @O_RDONLY
%4 = tail call i32 @open(i8* getelementptr inbounds ([7 x i8], [7 x i8]* @.str, i64 0, i64 0), i32 %3)
%5 = icmp slt i32 %4, 0
br i1 %5, label %6, label %8
6: ; preds = %2
%7 = tail call i32 @perror(i8* getelementptr inbounds ([12 x i8], [12 x i8]* @.str.1, i64 0, i64 0))
br label %11
8: ; preds = %2
%9 = tail call i32 @printf(i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.2, i64 0, i64 0), i32 %4)
%10 = tail call i32 @close(i32 %4)
br label %11
11: ; preds = %6, %8
%12 = phi i32 [ -1, %6 ], [ 0, %8 ]
ret i32 %12
}