#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*/ fclose(int /*<<< orphan*/ *);
int /*<<< orphan*/ *fopen(char *, char *);
unsigned int fread(char *, int, unsigned int, int /*<<< orphan*/ *);
int /*<<< orphan*/ fseek(int /*<<< orphan*/ *, int /*<<< orphan*/,
                         int /*<<< orphan*/);
unsigned int ftell(int /*<<< orphan*/ *);
char *malloc(unsigned int);
int /*<<< orphan*/ rewind(int /*<<< orphan*/ *);
char *read_file(char *path) {
  FILE *fp;
  char *buf;
  unsigned len;
  if ((fp = fopen(path, "rb")) == NULL)
    return NULL;
  fseek(fp, 0, SEEK_END);
  len = ftell(fp);
  rewind(fp);
  buf = malloc(len + 1);
  len = fread(buf, 1, len, fp);
  buf[len] = '\0';
  fclose(fp);
  return buf;
}


x86 assembly (clang, -O0):
<read_file>:
push   %rbp
mov    %rsp,%rbp
sub    $0x30,%rsp
mov    %rdi,-0x10(%rbp)
mov    -0x10(%rbp),%rdi
lea    0xe79(%rip),%rsi
call   1090 <fopen@plt>
mov    %rax,-0x18(%rbp)
cmp    $0x0,%rax
jne    11a7 <read_file+0x37>
movq   $0x0,-0x8(%rbp)
jmp    1213 <read_file+0xa3>
mov    -0x18(%rbp),%rdi
mov    0x2e36(%rip),%rax
mov    (%rax),%edx
xor    %esi,%esi
call   1080 <fseek@plt>
mov    -0x18(%rbp),%rdi
call   1060 <ftell@plt>
mov    %eax,-0x24(%rbp)
mov    -0x18(%rbp),%rdi
call   1050 <rewind@plt>
mov    -0x24(%rbp),%edi
add    $0x1,%edi
call   1070 <malloc@plt>
mov    %rax,-0x20(%rbp)
mov    -0x20(%rbp),%rdi
mov    -0x24(%rbp),%edx
mov    -0x18(%rbp),%rcx
mov    $0x1,%esi
call   1030 <fread@plt>
mov    %eax,-0x24(%rbp)
mov    -0x20(%rbp),%rax
mov    -0x24(%rbp),%ecx
movb   $0x0,(%rax,%rcx,1)
mov    -0x18(%rbp),%rdi
call   1040 <fclose@plt>
mov    -0x20(%rbp),%rax
mov    %rax,-0x8(%rbp)
mov    -0x8(%rbp),%rax
add    $0x30,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<read_file>:
push   %r15
push   %r14
push   %rbx
lea    0xe84(%rip),%rsi
call   1090 <fopen@plt>
test   %rax,%rax
je     11df <read_file+0x6f>
mov    %rax,%rbx
mov    0x2e58(%rip),%rax
mov    (%rax),%edx
mov    %rbx,%rdi
xor    %esi,%esi
call   1080 <fseek@plt>
mov    %rbx,%rdi
call   1060 <ftell@plt>
mov    %eax,%r15d
mov    %rbx,%rdi
call   1050 <rewind@plt>
lea    0x1(%r15),%edi
call   1070 <malloc@plt>
mov    %rax,%r14
mov    %rax,%rdi
mov    $0x1,%esi
mov    %r15d,%edx
mov    %rbx,%rcx
call   1030 <fread@plt>
mov    %eax,%eax
movb   $0x0,(%r14,%rax,1)
mov    %rbx,%rdi
call   1040 <fclose@plt>
jmp    11e2 <read_file+0x72>
xor    %r14d,%r14d
mov    %r14,%rax
pop    %rbx
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
@.str = [3 x i8] c"rb\00"
@SEEK_END = global i32 0
define i8* @read_file(i8* %0) {
%2 = alloca i8*
%3 = alloca i8*
%4 = alloca i32*
%5 = alloca i8*
%6 = alloca i32
store i8* %0, i8** %3
%7 = load i8*, i8** %3
%8 = call i32* @fopen(i8* %7, i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0))
store i32* %8, i32** %4
%9 = icmp eq i32* %8, null
br i1 %9, label %10, label %11
10: ; preds = %1
store i8* null, i8** %2
br label %33
11: ; preds = %1
%12 = load i32*, i32** %4
%13 = load i32, i32* @SEEK_END
%14 = call i32 @fseek(i32* %12, i32 0, i32 %13)
%15 = load i32*, i32** %4
%16 = call i32 @ftell(i32* %15)
store i32 %16, i32* %6
%17 = load i32*, i32** %4
%18 = call i32 @rewind(i32* %17)
%19 = load i32, i32* %6
%20 = add i32 %19, 1
%21 = call i8* @malloc(i32 %20)
store i8* %21, i8** %5
%22 = load i8*, i8** %5
%23 = load i32, i32* %6
%24 = load i32*, i32** %4
%25 = call i32 @fread(i8* %22, i32 1, i32 %23, i32* %24)
store i32 %25, i32* %6
%26 = load i8*, i8** %5
%27 = load i32, i32* %6
%28 = zext i32 %27 to i64
%29 = getelementptr inbounds i8, i8* %26, i64 %28
store i8 0, i8* %29
%30 = load i32*, i32** %4
%31 = call i32 @fclose(i32* %30)
%32 = load i8*, i8** %5
store i8* %32, i8** %2
br label %33
33: ; preds = %11, %10
%34 = load i8*, i8** %2
ret i8* %34
}

LLVM IR (-O2):
@.str = [3 x i8] c"rb\00"
@SEEK_END = global i32 0
define noalias i8* @read_file(i8* nocapture %0) {
%2 = tail call i32* @fopen(i8* %0, i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0))
%3 = icmp eq i32* %2, null
br i1 %3, label %15, label %4
4: ; preds = %1
%5 = load i32, i32* @SEEK_END
%6 = tail call i32 @fseek(i32* %2, i32 0, i32 %5)
%7 = tail call i32 @ftell(i32* %2)
%8 = tail call i32 @rewind(i32* %2)
%9 = add i32 %7, 1
%10 = tail call i8* @malloc(i32 %9)
%11 = tail call i32 @fread(i8* %10, i32 1, i32 %7, i32* %2)
%12 = zext i32 %11 to i64
%13 = getelementptr inbounds i8, i8* %10, i64 %12
store i8 0, i8* %13
%14 = tail call i32 @fclose(i32* %2)
br label %15
15: ; preds = %1, %4
%16 = phi i8* [ %10, %4 ], [ null, %1 ]
ret i8* %16
}