char *intToPrefix(int n) {
  switch (n) {
    break;
  case 0:
    return ("no-");
  case 1:
    return ("mono");
    break;
  case 2:
    return ("di");
    break;
  case 3:
    return ("tri");
    break;
  case 4:
    return ("tetra");
    break;
  case 5:
    return ("penta");
    break;
  case 6:
    return ("hexa");
    break;
  case 7:
    return ("hepta");
    break;
  case 8:
    return ("octa");
    break;
  case 9:
    return ("ennea");
    break;
  case 10:
    return ("hexa");
    break;
  case 11:
    return ("hendeca");
    break;
  case 12:
    return ("dodeca");
    break;
  case 13:
    return ("trideca");
    break;
  case 14:
    return ("tetradeca");
    break;
  case 15:
    return ("pentadeca");
    break;
  case 16:
    return ("hexadeca");
    break;
  case 17:
    return ("heptadeca");
    break;
  case 18:
    return ("octadeca");
    break;
  case 19:
    return ("enneadeca");
    break;
  case 20:
    return ("icosa");
    break;
  default:
    return ("poly");
  }
}


x86 assembly (clang, -O0):
<intToPrefix>:
push   %rbp
mov    %rsp,%rbp
mov    %edi,-0xc(%rbp)
mov    -0xc(%rbp),%eax
mov    %rax,-0x18(%rbp)
sub    $0x14,%rax
ja     127c <intToPrefix+0x17c>
mov    -0x18(%rbp),%rax
lea    0xedd(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
jmp    *%rax
lea    0xf21(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xf15(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xf0a(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xefd(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xef1(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xee7(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xedd(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xed2(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xec8(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xebd(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xe9d(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xea3(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xe9b(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xe92(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xe8a(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xe84(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xe7e(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xe77(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xe71(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xe6a(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xe64(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1287 <intToPrefix+0x187>
lea    0xe5a(%rip),%rax
mov    %rax,-0x8(%rbp)
mov    -0x8(%rbp),%rax
pop    %rbp
ret

x86 assembly (clang, -O2):
<intToPrefix>:
cmp    $0x14,%edi
ja     1117 <intToPrefix+0x17>
movslq %edi,%rax
lea    0xf81(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
ret
lea    0xf6b(%rip),%rax
ret

LLVM IR (-O0):
@.str = [4 x i8] c"no-\00"
@.str.1 = [5 x i8] c"mono\00"
@.str.2 = [3 x i8] c"di\00"
@.str.3 = [4 x i8] c"tri\00"
@.str.4 = [6 x i8] c"tetra\00"
@.str.5 = [6 x i8] c"penta\00"
@.str.6 = [5 x i8] c"hexa\00"
@.str.7 = [6 x i8] c"hepta\00"
@.str.8 = [5 x i8] c"octa\00"
@.str.9 = [6 x i8] c"ennea\00"
@.str.10 = [8 x i8] c"hendeca\00"
@.str.11 = [7 x i8] c"dodeca\00"
@.str.12 = [8 x i8] c"trideca\00"
@.str.13 = [10 x i8] c"tetradeca\00"
@.str.14 = [10 x i8] c"pentadeca\00"
@.str.15 = [9 x i8] c"hexadeca\00"
@.str.16 = [10 x i8] c"heptadeca\00"
@.str.17 = [9 x i8] c"octadeca\00"
@.str.18 = [10 x i8] c"enneadeca\00"
@.str.19 = [6 x i8] c"icosa\00"
@.str.20 = [5 x i8] c"poly\00"
define i8* @intToPrefix(i32 %0) {
%2 = alloca i8*
%3 = alloca i32
store i32 %0, i32* %3
%4 = load i32, i32* %3
switch i32 %4, label %26 [
i32 0, label %5
i32 1, label %6
i32 2, label %7
i32 3, label %8
i32 4, label %9
i32 5, label %10
i32 6, label %11
i32 7, label %12
i32 8, label %13
i32 9, label %14
i32 10, label %15
i32 11, label %16
i32 12, label %17
i32 13, label %18
i32 14, label %19
i32 15, label %20
i32 16, label %21
i32 17, label %22
i32 18, label %23
i32 19, label %24
i32 20, label %25
]
5: ; preds = %1
store i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i8** %2
br label %27
6: ; preds = %1
store i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.1, i64 0, i64 0), i8** %2
br label %27
7: ; preds = %1
store i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.2, i64 0, i64 0), i8** %2
br label %27
8: ; preds = %1
store i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.3, i64 0, i64 0), i8** %2
br label %27
9: ; preds = %1
store i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.4, i64 0, i64 0), i8** %2
br label %27
10: ; preds = %1
store i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.5, i64 0, i64 0), i8** %2
br label %27
11: ; preds = %1
store i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.6, i64 0, i64 0), i8** %2
br label %27
12: ; preds = %1
store i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.7, i64 0, i64 0), i8** %2
br label %27
13: ; preds = %1
store i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.8, i64 0, i64 0), i8** %2
br label %27
14: ; preds = %1
store i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.9, i64 0, i64 0), i8** %2
br label %27
15: ; preds = %1
store i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.6, i64 0, i64 0), i8** %2
br label %27
16: ; preds = %1
store i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str.10, i64 0, i64 0), i8** %2
br label %27
17: ; preds = %1
store i8* getelementptr inbounds ([7 x i8], [7 x i8]* @.str.11, i64 0, i64 0), i8** %2
br label %27
18: ; preds = %1
store i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str.12, i64 0, i64 0), i8** %2
br label %27
19: ; preds = %1
store i8* getelementptr inbounds ([10 x i8], [10 x i8]* @.str.13, i64 0, i64 0), i8** %2
br label %27
20: ; preds = %1
store i8* getelementptr inbounds ([10 x i8], [10 x i8]* @.str.14, i64 0, i64 0), i8** %2
br label %27
21: ; preds = %1
store i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.15, i64 0, i64 0), i8** %2
br label %27
22: ; preds = %1
store i8* getelementptr inbounds ([10 x i8], [10 x i8]* @.str.16, i64 0, i64 0), i8** %2
br label %27
23: ; preds = %1
store i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.17, i64 0, i64 0), i8** %2
br label %27
24: ; preds = %1
store i8* getelementptr inbounds ([10 x i8], [10 x i8]* @.str.18, i64 0, i64 0), i8** %2
br label %27
25: ; preds = %1
store i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.19, i64 0, i64 0), i8** %2
br label %27
26: ; preds = %1
store i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.20, i64 0, i64 0), i8** %2
br label %27
27: ; preds = %26, %25, %24, %23, %22, %21, %20, %19, %18, %17, %16, %15, %14, %13, %12, %11, %10, %9, %8, %7, %6, %5
%28 = load i8*, i8** %2
ret i8* %28
}

LLVM IR (-O2):
@.str = [4 x i8] c"no-\00"
@.str.1 = [5 x i8] c"mono\00"
@.str.2 = [3 x i8] c"di\00"
@.str.3 = [4 x i8] c"tri\00"
@.str.4 = [6 x i8] c"tetra\00"
@.str.5 = [6 x i8] c"penta\00"
@.str.6 = [5 x i8] c"hexa\00"
@.str.7 = [6 x i8] c"hepta\00"
@.str.8 = [5 x i8] c"octa\00"
@.str.9 = [6 x i8] c"ennea\00"
@.str.10 = [8 x i8] c"hendeca\00"
@.str.11 = [7 x i8] c"dodeca\00"
@.str.12 = [8 x i8] c"trideca\00"
@.str.13 = [10 x i8] c"tetradeca\00"
@.str.14 = [10 x i8] c"pentadeca\00"
@.str.15 = [9 x i8] c"hexadeca\00"
@.str.16 = [10 x i8] c"heptadeca\00"
@.str.17 = [9 x i8] c"octadeca\00"
@.str.18 = [10 x i8] c"enneadeca\00"
@.str.19 = [6 x i8] c"icosa\00"
@.str.20 = [5 x i8] c"poly\00"
@reltable.intToPrefix = [21 x i32] [i32 trunc (i64 sub (i64 ptrtoint ([4 x i8]* @.str to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([5 x i8]* @.str.1 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([3 x i8]* @.str.2 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([4 x i8]* @.str.3 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.4 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.5 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([5 x i8]* @.str.6 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.7 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([5 x i8]* @.str.8 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.9 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([5 x i8]* @.str.6 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([8 x i8]* @.str.10 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([7 x i8]* @.str.11 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([8 x i8]* @.str.12 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([10 x i8]* @.str.13 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([10 x i8]* @.str.14 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([9 x i8]* @.str.15 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([10 x i8]* @.str.16 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([9 x i8]* @.str.17 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([10 x i8]* @.str.18 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.19 to i64), i64 ptrtoint ([21 x i32]* @reltable.intToPrefix to i64)) to i32)]
define i8* @intToPrefix(i32 %0) {
%2 = icmp ult i32 %0, 21
br i1 %2, label %3, label %7
3: ; preds = %1
%4 = sext i32 %0 to i64
%5 = shl i64 %4, 2
%6 = call i8* @llvm.load.relative.i64(i8* bitcast ([21 x i32]* @reltable.intToPrefix to i8*), i64 %5)
br label %7
7: ; preds = %1, %3
%8 = phi i8* [ %6, %3 ], [ getelementptr inbounds ([5 x i8], [5 x i8]* @.str.20, i64 0, i64 0), %1 ]
ret i8* %8
}