#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 */
scalar_t__ strcmp(char *, char *);
int arg_to_index(char *arg) {
  if (strcmp(arg, "-dos") == 0)
    return 0;
  if (strcmp(arg, "-mac") == 0)
    return 1;
  if (strcmp(arg, "-unix") == 0)
    return 2;
  return -1;
}


x86 assembly (clang, -O0):
<arg_to_index>:
push   %rbp
mov    %rsp,%rbp
sub    $0x10,%rsp
mov    %rdi,-0x10(%rbp)
mov    -0x10(%rbp),%rdi
lea    0xed9(%rip),%rsi
call   1030 <strcmp@plt>
cmp    $0x0,%rax
jne    1142 <arg_to_index+0x32>
movl   $0x0,-0x4(%rbp)
jmp    1195 <arg_to_index+0x85>
mov    -0x10(%rbp),%rdi
lea    0xeb8(%rip),%rsi
call   1030 <strcmp@plt>
cmp    $0x0,%rax
jne    1168 <arg_to_index+0x58>
movl   $0x1,-0x4(%rbp)
jmp    1195 <arg_to_index+0x85>
mov    -0x10(%rbp),%rdi
lea    0xe97(%rip),%rsi
call   1030 <strcmp@plt>
cmp    $0x0,%rax
jne    118e <arg_to_index+0x7e>
movl   $0x2,-0x4(%rbp)
jmp    1195 <arg_to_index+0x85>
movl   $0xffffffff,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x10,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<arg_to_index>:
push   %rbx
mov    %rdi,%rbx
lea    0xee5(%rip),%rsi
call   1030 <strcmp@plt>
test   %rax,%rax
je     1152 <arg_to_index+0x42>
lea    0xed9(%rip),%rsi
mov    %rbx,%rdi
call   1030 <strcmp@plt>
test   %rax,%rax
je     1156 <arg_to_index+0x46>
lea    0xeca(%rip),%rsi
mov    %rbx,%rdi
call   1030 <strcmp@plt>
neg    %rax
sbb    %eax,%eax
or     $0x2,%eax
pop    %rbx
ret
xor    %eax,%eax
pop    %rbx
ret
mov    $0x1,%eax
pop    %rbx
ret

LLVM IR (-O0):
@.str = [5 x i8] c"-dos\00"
@.str.1 = [5 x i8] c"-mac\00"
@.str.2 = [6 x i8] c"-unix\00"
define i32 @arg_to_index(i8* %0) {
%2 = alloca i32
%3 = alloca i8*
store i8* %0, i8** %3
%4 = load i8*, i8** %3
%5 = call i64 @strcmp(i8* %4, i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str, i64 0, i64 0))
%6 = icmp eq i64 %5, 0
br i1 %6, label %7, label %8
7: ; preds = %1
store i32 0, i32* %2
br label %19
8: ; preds = %1
%9 = load i8*, i8** %3
%10 = call i64 @strcmp(i8* %9, i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.1, i64 0, i64 0))
%11 = icmp eq i64 %10, 0
br i1 %11, label %12, label %13
12: ; preds = %8
store i32 1, i32* %2
br label %19
13: ; preds = %8
%14 = load i8*, i8** %3
%15 = call i64 @strcmp(i8* %14, i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.2, i64 0, i64 0))
%16 = icmp eq i64 %15, 0
br i1 %16, label %17, label %18
17: ; preds = %13
store i32 2, i32* %2
br label %19
18: ; preds = %13
store i32 -1, i32* %2
br label %19
19: ; preds = %18, %17, %12, %7
%20 = load i32, i32* %2
ret i32 %20
}

LLVM IR (-O2):
@.str = [5 x i8] c"-dos\00"
@.str.1 = [5 x i8] c"-mac\00"
@.str.2 = [6 x i8] c"-unix\00"
define i32 @arg_to_index(i8* %0) {
%2 = tail call i64 @strcmp(i8* %0, i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str, i64 0, i64 0))
%3 = icmp eq i64 %2, 0
br i1 %3, label %11, label %4
4: ; preds = %1
%5 = tail call i64 @strcmp(i8* %0, i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.1, i64 0, i64 0))
%6 = icmp eq i64 %5, 0
br i1 %6, label %11, label %7
7: ; preds = %4
%8 = tail call i64 @strcmp(i8* %0, i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.2, i64 0, i64 0))
%9 = icmp eq i64 %8, 0
%10 = select i1 %9, i32 2, i32 -1
br label %11
11: ; preds = %7, %4, %1
%12 = phi i32 [ 0, %1 ], [ 1, %4 ], [ %10, %7 ]
ret i32 %12
}