char *type_to_name(char t) {
  switch (t) {
  case 0x01:
    return "fat12";
  case 0x04:
  case 0x06:
  case 0x0E:
    return "fat16";
  case 0x0B:
  case 0x0C:
    return "fat32";
  case 0x0F:
  case 0x05:
    return "extended";
  }
  return "not supported";
}


x86 assembly (clang, -O0):
<type_to_name>:
push   %rbp
mov    %rsp,%rbp
mov    %dil,%al
mov    %al,-0x9(%rbp)
movsbl -0x9(%rbp),%eax
add    $0xffffffff,%eax
mov    %eax,%ecx
mov    %rcx,-0x18(%rbp)
sub    $0xe,%eax
ja     1174 <type_to_name+0x74>
mov    -0x18(%rbp),%rax
lea    0xed5(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
jmp    *%rax
lea    0xf01(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    117f <type_to_name+0x7f>
lea    0xef7(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    117f <type_to_name+0x7f>
lea    0xeed(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    117f <type_to_name+0x7f>
lea    0xee3(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    117f <type_to_name+0x7f>
lea    0xedc(%rip),%rax
mov    %rax,-0x8(%rbp)
mov    -0x8(%rbp),%rax
pop    %rbp
ret

x86 assembly (clang, -O2):
<type_to_name>:
add    $0xffffffff,%edi
cmp    $0xe,%edi
ja     111a <type_to_name+0x1a>
movslq %edi,%rax
lea    0xf1a(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
ret
lea    0xefa(%rip),%rax
ret

LLVM IR (-O0):
@.str = [6 x i8] c"fat12\00"
@.str.1 = [6 x i8] c"fat16\00"
@.str.2 = [6 x i8] c"fat32\00"
@.str.3 = [9 x i8] c"extended\00"
@.str.4 = [14 x i8] c"not supported\00"
define i8* @type_to_name(i8 signext %0) {
%2 = alloca i8*
%3 = alloca i8
store i8 %0, i8* %3
%4 = load i8, i8* %3
%5 = sext i8 %4 to i32
switch i32 %5, label %10 [
i32 1, label %6
i32 4, label %7
i32 6, label %7
i32 14, label %7
i32 11, label %8
i32 12, label %8
i32 15, label %9
i32 5, label %9
]
6: ; preds = %1
store i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str, i64 0, i64 0), i8** %2
br label %11
7: ; preds = %1, %1, %1
store i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.1, i64 0, i64 0), i8** %2
br label %11
8: ; preds = %1, %1
store i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.2, i64 0, i64 0), i8** %2
br label %11
9: ; preds = %1, %1
store i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.3, i64 0, i64 0), i8** %2
br label %11
10: ; preds = %1
store i8* getelementptr inbounds ([14 x i8], [14 x i8]* @.str.4, i64 0, i64 0), i8** %2
br label %11
11: ; preds = %10, %9, %8, %7, %6
%12 = load i8*, i8** %2
ret i8* %12
}

LLVM IR (-O2):
@.str = [6 x i8] c"fat12\00"
@.str.1 = [6 x i8] c"fat16\00"
@.str.2 = [6 x i8] c"fat32\00"
@.str.3 = [9 x i8] c"extended\00"
@.str.4 = [14 x i8] c"not supported\00"
@reltable.type_to_name = [15 x i32] [i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([14 x i8]* @.str.4 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([14 x i8]* @.str.4 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.1 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([9 x i8]* @.str.3 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.1 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([14 x i8]* @.str.4 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([14 x i8]* @.str.4 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([14 x i8]* @.str.4 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([14 x i8]* @.str.4 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.2 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.2 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([14 x i8]* @.str.4 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.1 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([9 x i8]* @.str.3 to i64), i64 ptrtoint ([15 x i32]* @reltable.type_to_name to i64)) to i32)]
define i8* @type_to_name(i8 signext %0) {
%2 = sext i8 %0 to i32
%3 = add nsw i32 %2, -1
%4 = icmp ult i32 %3, 15
br i1 %4, label %5, label %9
5: ; preds = %1
%6 = sext i32 %3 to i64
%7 = shl i64 %6, 2
%8 = call i8* @llvm.load.relative.i64(i8* bitcast ([15 x i32]* @reltable.type_to_name to i8*), i64 %7)
br label %9
9: ; preds = %1, %5
%10 = phi i8* [ %8, %5 ], [ getelementptr inbounds ([14 x i8], [14 x i8]* @.str.4, i64 0, i64 0), %1 ]
ret i8* %10
}