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

/* Variables and functions */
int /*<<< orphan*/ fclose(int /*<<< orphan*/ *);
int /*<<< orphan*/ *fopen(char const *, char *);
int /*<<< orphan*/ fscanf(int /*<<< orphan*/ *, char *, int /*<<< orphan*/ *);
int read_pid_file(pid_t *pid, const char *file) {
  FILE *fp = fopen(file, "r");
  if (fp == NULL) {
    return -1;
  }
  fscanf(fp, "%d", pid);
  fclose(fp);
  return 0;
}


x86 assembly (clang, -O0):
<read_pid_file>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
mov    %rdi,-0x10(%rbp)
mov    %rsi,-0x18(%rbp)
mov    -0x18(%rbp),%rdi
lea    0xeb5(%rip),%rsi
call   1050 <fopen@plt>
mov    %rax,-0x20(%rbp)
cmpq   $0x0,-0x20(%rbp)
jne    116b <read_pid_file+0x3b>
movl   $0xffffffff,-0x4(%rbp)
jmp    118f <read_pid_file+0x5f>
mov    -0x20(%rbp),%rdi
mov    -0x10(%rbp),%rdx
lea    0xe88(%rip),%rsi
call   1040 <fscanf@plt>
mov    -0x20(%rbp),%rdi
call   1030 <fclose@plt>
movl   $0x0,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<read_pid_file>:
push   %r14
push   %rbx
push   %rax
mov    %rsi,%rax
mov    %rdi,%r14
lea    0xebf(%rip),%rsi
mov    %rax,%rdi
call   1050 <fopen@plt>
test   %rax,%rax
je     116f <read_pid_file+0x3f>
mov    %rax,%rbx
lea    0xeaa(%rip),%rsi
mov    %rax,%rdi
mov    %r14,%rdx
call   1040 <fscanf@plt>
mov    %rbx,%rdi
call   1030 <fclose@plt>
xor    %eax,%eax
jmp    1174 <read_pid_file+0x44>
mov    $0xffffffff,%eax
add    $0x8,%rsp
pop    %rbx
pop    %r14
ret

LLVM IR (-O0):
@.str = [2 x i8] c"r\00"
@.str.1 = [3 x i8] c"%d\00"
define i32 @read_pid_file(i32* %0, i8* %1) {
%3 = alloca i32
%4 = alloca i32*
%5 = alloca i8*
%6 = alloca i32*
store i32* %0, i32** %4
store i8* %1, i8** %5
%7 = load i8*, i8** %5
%8 = call i32* @fopen(i8* %7, i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str, i64 0, i64 0))
store i32* %8, i32** %6
%9 = load i32*, i32** %6
%10 = icmp eq i32* %9, null
br i1 %10, label %11, label %12
11: ; preds = %2
store i32 -1, i32* %3
br label %18
12: ; preds = %2
%13 = load i32*, i32** %6
%14 = load i32*, i32** %4
%15 = call i32 @fscanf(i32* %13, i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i32* %14)
%16 = load i32*, i32** %6
%17 = call i32 @fclose(i32* %16)
store i32 0, i32* %3
br label %18
18: ; preds = %12, %11
%19 = load i32, i32* %3
ret i32 %19
}

LLVM IR (-O2):
@.str = [2 x i8] c"r\00"
@.str.1 = [3 x i8] c"%d\00"
define i32 @read_pid_file(i32* %0, i8* nocapture %1) {
%3 = tail call i32* @fopen(i8* %1, i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str, i64 0, i64 0))
%4 = icmp eq i32* %3, null
br i1 %4, label %8, label %5
5: ; preds = %2
%6 = tail call i32 @fscanf(i32* %3, i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.1, i64 0, i64 0), i32* %0)
%7 = tail call i32 @fclose(i32* %3)
br label %8
8: ; preds = %2, %5
%9 = phi i32 [ 0, %5 ], [ -1, %2 ]
ret i32 %9
}