#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*/ SEEK_END;
int /*<<< orphan*/ SEEK_SET;
int /*<<< orphan*/ fclose(int /*<<< orphan*/ *);
int /*<<< orphan*/ *fopen(char const *, char *);
int /*<<< orphan*/ fprintf(int /*<<< orphan*/, char *, char const *);
int fread(void *, int, int, int /*<<< orphan*/ *);
int /*<<< orphan*/ fseek(int /*<<< orphan*/ *, int /*<<< orphan*/,
                         int /*<<< orphan*/);
int ftell(int /*<<< orphan*/ *);
void *malloc(int);
int /*<<< orphan*/ stderr;
char *file_contents(const char *filename, int *length) {
  FILE *f = fopen(filename, "r");
  void *buffer;
  if (!f) {
    fprintf(stderr, "Unable to open %s for reading\n", filename);
    return NULL;
  }
  fseek(f, 0, SEEK_END);
  *length = ftell(f);
  fseek(f, 0, SEEK_SET);
  buffer = malloc(*length + 1);
  *length = fread(buffer, 1, *length, f);
  fclose(f);
  ((char *)buffer)[*length] = '\0';
  return (char *)buffer;
}


x86 assembly (clang, -O0):
<file_contents>:
push   %rbp
mov    %rsp,%rbp
sub    $0x30,%rsp
mov    %rdi,-0x10(%rbp)
mov    %rsi,-0x18(%rbp)
mov    -0x10(%rbp),%rdi
lea    0xe75(%rip),%rsi
call   1090 <fopen@plt>
mov    %rax,-0x20(%rbp)
cmpq   $0x0,-0x20(%rbp)
jne    11c5 <file_contents+0x55>
mov    0x2e32(%rip),%rax
mov    (%rax),%edi
mov    -0x10(%rbp),%rdx
lea    0xe4f(%rip),%rsi
call   1050 <fprintf@plt>
movq   $0x0,-0x8(%rbp)
jmp    1250 <file_contents+0xe0>
mov    -0x20(%rbp),%rdi
mov    0x2e18(%rip),%rax
mov    (%rax),%edx
xor    %esi,%esi
call   1080 <fseek@plt>
mov    -0x20(%rbp),%rdi
call   1060 <ftell@plt>
mov    %eax,%ecx
mov    -0x18(%rbp),%rax
mov    %ecx,(%rax)
mov    -0x20(%rbp),%rdi
mov    0x2ddb(%rip),%rax
mov    (%rax),%edx
xor    %esi,%esi
call   1080 <fseek@plt>
mov    -0x18(%rbp),%rax
mov    (%rax),%edi
add    $0x1,%edi
call   1070 <malloc@plt>
mov    %rax,-0x28(%rbp)
mov    -0x28(%rbp),%rdi
mov    -0x18(%rbp),%rax
mov    (%rax),%edx
mov    -0x20(%rbp),%rcx
mov    $0x1,%esi
call   1030 <fread@plt>
mov    %eax,%ecx
mov    -0x18(%rbp),%rax
mov    %ecx,(%rax)
mov    -0x20(%rbp),%rdi
call   1040 <fclose@plt>
mov    -0x28(%rbp),%rax
mov    -0x18(%rbp),%rcx
movslq (%rcx),%rcx
movb   $0x0,(%rax,%rcx,1)
mov    -0x28(%rbp),%rax
mov    %rax,-0x8(%rbp)
mov    -0x8(%rbp),%rax
add    $0x30,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<file_contents>:
push   %r15
push   %r14
push   %r12
push   %rbx
push   %rax
mov    %rsi,%r14
mov    %rdi,%r15
lea    0xe7b(%rip),%rsi
call   1090 <fopen@plt>
test   %rax,%rax
je     11fb <file_contents+0x8b>
mov    %rax,%rbx
mov    0x2e4f(%rip),%rax
mov    (%rax),%edx
mov    %rbx,%rdi
xor    %esi,%esi
call   1080 <fseek@plt>
mov    %rbx,%rdi
call   1060 <ftell@plt>
mov    %eax,(%r14)
mov    0x2e19(%rip),%rax
mov    (%rax),%edx
mov    %rbx,%rdi
xor    %esi,%esi
call   1080 <fseek@plt>
mov    (%r14),%r12d
lea    0x1(%r12),%edi
call   1070 <malloc@plt>
mov    %rax,%r15
mov    %rax,%rdi
mov    $0x1,%esi
mov    %r12d,%edx
mov    %rbx,%rcx
call   1030 <fread@plt>
mov    %eax,(%r14)
mov    %rbx,%rdi
call   1040 <fclose@plt>
movslq (%r14),%rax
movb   $0x0,(%r15,%rax,1)
jmp    1216 <file_contents+0xa6>
mov    0x2dd6(%rip),%rax
mov    (%rax),%edi
lea    0xdf7(%rip),%rsi
mov    %r15,%rdx
call   1050 <fprintf@plt>
xor    %r15d,%r15d
mov    %r15,%rax
add    $0x8,%rsp
pop    %rbx
pop    %r12
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
@.str = [2 x i8] c"r\00"
@stderr = global i32 0
@.str.1 = [31 x i8] c"Unable to open %s for reading\0A\00"
@SEEK_END = global i32 0
@SEEK_SET = global i32 0
define i8* @file_contents(i8* %0, i32* %1) {
%3 = alloca i8*
%4 = alloca i8*
%5 = alloca i32*
%6 = alloca i32*
%7 = alloca i8*
store i8* %0, i8** %4
store i32* %1, i32** %5
%8 = load i8*, i8** %4
%9 = call i32* @fopen(i8* %8, i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str, i64 0, i64 0))
store i32* %9, i32** %6
%10 = load i32*, i32** %6
%11 = icmp ne i32* %10, null
br i1 %11, label %16, label %12
12: ; preds = %2
%13 = load i32, i32* @stderr
%14 = load i8*, i8** %4
%15 = call i32 @fprintf(i32 %13, i8* getelementptr inbounds ([31 x i8], [31 x i8]* @.str.1, i64 0, i64 0), i8* %14)
store i8* null, i8** %3
br label %44
16: ; preds = %2
%17 = load i32*, i32** %6
%18 = load i32, i32* @SEEK_END
%19 = call i32 @fseek(i32* %17, i32 0, i32 %18)
%20 = load i32*, i32** %6
%21 = call i32 @ftell(i32* %20)
%22 = load i32*, i32** %5
store i32 %21, i32* %22
%23 = load i32*, i32** %6
%24 = load i32, i32* @SEEK_SET
%25 = call i32 @fseek(i32* %23, i32 0, i32 %24)
%26 = load i32*, i32** %5
%27 = load i32, i32* %26
%28 = add nsw i32 %27, 1
%29 = call i8* @malloc(i32 %28)
store i8* %29, i8** %7
%30 = load i8*, i8** %7
%31 = load i32*, i32** %5
%32 = load i32, i32* %31
%33 = load i32*, i32** %6
%34 = call i32 @fread(i8* %30, i32 1, i32 %32, i32* %33)
%35 = load i32*, i32** %5
store i32 %34, i32* %35
%36 = load i32*, i32** %6
%37 = call i32 @fclose(i32* %36)
%38 = load i8*, i8** %7
%39 = load i32*, i32** %5
%40 = load i32, i32* %39
%41 = sext i32 %40 to i64
%42 = getelementptr inbounds i8, i8* %38, i64 %41
store i8 0, i8* %42
%43 = load i8*, i8** %7
store i8* %43, i8** %3
br label %44
44: ; preds = %16, %12
%45 = load i8*, i8** %3
ret i8* %45
}

LLVM IR (-O2):
@.str = [2 x i8] c"r\00"
@stderr = global i32 0
@.str.1 = [31 x i8] c"Unable to open %s for reading\0A\00"
@SEEK_END = global i32 0
@SEEK_SET = global i32 0
define noalias i8* @file_contents(i8* %0, i32* nocapture %1) {
%3 = tail call i32* @fopen(i8* %0, i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str, i64 0, i64 0))
%4 = icmp eq i32* %3, null
br i1 %4, label %5, label %8
5: ; preds = %2
%6 = load i32, i32* @stderr
%7 = tail call i32 @fprintf(i32 %6, i8* getelementptr inbounds ([31 x i8], [31 x i8]* @.str.1, i64 0, i64 0), i8* %0)
br label %22
8: ; preds = %2
%9 = load i32, i32* @SEEK_END
%10 = tail call i32 @fseek(i32* %3, i32 0, i32 %9)
%11 = tail call i32 @ftell(i32* %3)
store i32 %11, i32* %1
%12 = load i32, i32* @SEEK_SET
%13 = tail call i32 @fseek(i32* %3, i32 0, i32 %12)
%14 = load i32, i32* %1
%15 = add nsw i32 %14, 1
%16 = tail call i8* @malloc(i32 %15)
%17 = tail call i32 @fread(i8* %16, i32 1, i32 %14, i32* %3)
store i32 %17, i32* %1
%18 = tail call i32 @fclose(i32* %3)
%19 = load i32, i32* %1
%20 = sext i32 %19 to i64
%21 = getelementptr inbounds i8, i8* %16, i64 %20
store i8 0, i8* %21
br label %22
22: ; preds = %8, %5
%23 = phi i8* [ %16, %8 ], [ null, %5 ]
ret i8* %23
}