#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 *);
int /*<<< orphan*/ fseek(int /*<<< orphan*/ *, int /*<<< orphan*/,
                         int /*<<< orphan*/);
long ftell(int /*<<< orphan*/ *);
int /*<<< orphan*/ perror(char *);
size_t FSize(char *FName) {
  long FS;
  FILE *F;
  if ((F = fopen(FName, "rb")) == NULL) {
    perror("Unable to open file");
    return 0;
  }
  fseek(F, 0, SEEK_END);
  FS = ftell(F);
  fclose(F);
  return (size_t)FS;
}


x86 assembly (clang, -O0):
<FSize>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
mov    %rdi,-0x10(%rbp)
mov    -0x10(%rbp),%rdi
lea    0xe99(%rip),%rsi
call   1060 <fopen@plt>
mov    %rax,-0x20(%rbp)
cmp    $0x0,%rax
jne    1193 <FSize+0x43>
lea    0xe82(%rip),%rdi
call   1070 <perror@plt>
movq   $0x0,-0x8(%rbp)
jmp    11c5 <FSize+0x75>
mov    -0x20(%rbp),%rdi
mov    0x2e4a(%rip),%rax
mov    (%rax),%edx
xor    %esi,%esi
call   1050 <fseek@plt>
mov    -0x20(%rbp),%rdi
call   1040 <ftell@plt>
mov    %rax,-0x18(%rbp)
mov    -0x20(%rbp),%rdi
call   1030 <fclose@plt>
mov    -0x18(%rbp),%rax
mov    %rax,-0x8(%rbp)
mov    -0x8(%rbp),%rax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<FSize>:
push   %r14
push   %rbx
push   %rax
lea    0xea5(%rip),%rsi
call   1060 <fopen@plt>
test   %rax,%rax
je     1199 <FSize+0x49>
mov    %rax,%rbx
mov    0x2e79(%rip),%rax
mov    (%rax),%edx
mov    %rbx,%rdi
xor    %esi,%esi
call   1050 <fseek@plt>
mov    %rbx,%rdi
call   1040 <ftell@plt>
mov    %rax,%r14
mov    %rbx,%rdi
call   1030 <fclose@plt>
mov    %r14,%rax
add    $0x8,%rsp
pop    %rbx
pop    %r14
ret
lea    0xe63(%rip),%rdi
call   1070 <perror@plt>
xor    %eax,%eax
jmp    1191 <FSize+0x41>

LLVM IR (-O0):
@.str = [3 x i8] c"rb\00"
@.str.1 = [20 x i8] c"Unable to open file\00"
@SEEK_END = global i32 0
define i64 @FSize(i8* %0) {
%2 = alloca i64
%3 = alloca i8*
%4 = alloca i64
%5 = alloca i32*
store i8* %0, i8** %3
%6 = load i8*, i8** %3
%7 = call i32* @fopen(i8* %6, i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str, i64 0, i64 0))
store i32* %7, i32** %5
%8 = icmp eq i32* %7, null
br i1 %8, label %9, label %11
9: ; preds = %1
%10 = call i32 @perror(i8* getelementptr inbounds ([20 x i8], [20 x i8]* @.str.1, i64 0, i64 0))
store i64 0, i64* %2
br label %20
11: ; preds = %1
%12 = load i32*, i32** %5
%13 = load i32, i32* @SEEK_END
%14 = call i32 @fseek(i32* %12, i32 0, i32 %13)
%15 = load i32*, i32** %5
%16 = call i64 @ftell(i32* %15)
store i64 %16, i64* %4
%17 = load i32*, i32** %5
%18 = call i32 @fclose(i32* %17)
%19 = load i64, i64* %4
store i64 %19, i64* %2
br label %20
20: ; preds = %11, %9
%21 = load i64, i64* %2
ret i64 %21
}

LLVM IR (-O2):
@.str = [3 x i8] c"rb\00"
@.str.1 = [20 x i8] c"Unable to open file\00"
@SEEK_END = global i32 0
define i64 @FSize(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 %4, label %6
4: ; preds = %1
%5 = tail call i32 @perror(i8* getelementptr inbounds ([20 x i8], [20 x i8]* @.str.1, i64 0, i64 0))
br label %11
6: ; preds = %1
%7 = load i32, i32* @SEEK_END
%8 = tail call i32 @fseek(i32* %2, i32 0, i32 %7)
%9 = tail call i64 @ftell(i32* %2)
%10 = tail call i32 @fclose(i32* %2)
br label %11
11: ; preds = %6, %4
%12 = phi i64 [ 0, %4 ], [ %9, %6 ]
ret i64 %12
}