int message_lenght(char buffer_start) {
  switch (buffer_start) {
  case (char)0x00:
    return 1;
    break;
  case (char)0x02:
    return 9;
    break;
  case (char)0x03:
    return 524;
    break;
  case (char)0x04:
    return 129;
    break;
  case (char)0x06:
    return 9;
    break;
  case (char)0x07:
    return 33;
    break;
  case (char)0x08:
    return 17;
    break;
  case (char)0x09:
    return 9;
    break;
  case (char)0x0a:
    return 33;
    break;
  case (char)0x0b:
    return 25;
    break;
  default:
    return 524;
  }
}


x86 assembly (clang, -O0):
<message_lenght>:
push   %rbp
mov    %rsp,%rbp
mov    %dil,%al
mov    %al,-0x5(%rbp)
movsbl -0x5(%rbp),%eax
mov    %eax,%ecx
mov    %rcx,-0x10(%rbp)
sub    $0xb,%eax
ja     11a9 <message_lenght+0xa9>
mov    -0x10(%rbp),%rax
lea    0xed8(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
jmp    *%rax
movl   $0x1,-0x4(%rbp)
jmp    11b0 <message_lenght+0xb0>
movl   $0x9,-0x4(%rbp)
jmp    11b0 <message_lenght+0xb0>
movl   $0x20c,-0x4(%rbp)
jmp    11b0 <message_lenght+0xb0>
movl   $0x81,-0x4(%rbp)
jmp    11b0 <message_lenght+0xb0>
movl   $0x9,-0x4(%rbp)
jmp    11b0 <message_lenght+0xb0>
movl   $0x21,-0x4(%rbp)
jmp    11b0 <message_lenght+0xb0>
movl   $0x11,-0x4(%rbp)
jmp    11b0 <message_lenght+0xb0>
movl   $0x9,-0x4(%rbp)
jmp    11b0 <message_lenght+0xb0>
movl   $0x21,-0x4(%rbp)
jmp    11b0 <message_lenght+0xb0>
movl   $0x19,-0x4(%rbp)
jmp    11b0 <message_lenght+0xb0>
movl   $0x20c,-0x4(%rbp)
mov    -0x4(%rbp),%eax
pop    %rbp
ret

x86 assembly (clang, -O2):
<message_lenght>:
mov    $0x20c,%eax
cmp    $0xb,%dil
ja     1119 <message_lenght+0x19>
movsbq %dil,%rax
lea    0xeea(%rip),%rcx
mov    (%rcx,%rax,4),%eax
ret

LLVM IR (-O0):
define i32 @message_lenght(i8 signext %0) {
%2 = alloca i32
%3 = alloca i8
store i8 %0, i8* %3
%4 = load i8, i8* %3
%5 = sext i8 %4 to i32
switch i32 %5, label %16 [
i32 0, label %6
i32 2, label %7
i32 3, label %8
i32 4, label %9
i32 6, label %10
i32 7, label %11
i32 8, label %12
i32 9, label %13
i32 10, label %14
i32 11, label %15
]
6: ; preds = %1
store i32 1, i32* %2
br label %17
7: ; preds = %1
store i32 9, i32* %2
br label %17
8: ; preds = %1
store i32 524, i32* %2
br label %17
9: ; preds = %1
store i32 129, i32* %2
br label %17
10: ; preds = %1
store i32 9, i32* %2
br label %17
11: ; preds = %1
store i32 33, i32* %2
br label %17
12: ; preds = %1
store i32 17, i32* %2
br label %17
13: ; preds = %1
store i32 9, i32* %2
br label %17
14: ; preds = %1
store i32 33, i32* %2
br label %17
15: ; preds = %1
store i32 25, i32* %2
br label %17
16: ; preds = %1
store i32 524, i32* %2
br label %17
17: ; preds = %16, %15, %14, %13, %12, %11, %10, %9, %8, %7, %6
%18 = load i32, i32* %2
ret i32 %18
}

LLVM IR (-O2):
@switch.table.message_lenght = [12 x i32] [i32 1, i32 524, i32 9, i32 524, i32 129, i32 524, i32 9, i32 33, i32 17, i32 9, i32 33, i32 25]
define i32 @message_lenght(i8 signext %0) {
%2 = icmp ult i8 %0, 12
br i1 %2, label %3, label %7
3: ; preds = %1
%4 = sext i8 %0 to i64
%5 = getelementptr inbounds [12 x i32], [12 x i32]* @switch.table.message_lenght, i64 0, i64 %4
%6 = load i32, i32* %5
br label %7
7: ; preds = %1, %3
%8 = phi i32 [ %6, %3 ], [ 524, %1 ]
ret i32 %8
}