const char *pkt_name(int type) {
  switch (type) {
  case 0x00:
    return "STATUS";
  case 0x10:
    return "GET";
  case 0x20:
    return "POST";
  case 0x30:
    return "CRITICAL";
  case 0x40:
    return "ASYNC";
  default:
    return "UNKNOWN";
  }
}


x86 assembly (clang, -O0):
<pkt_name>:
push   %rbp
mov    %rsp,%rbp
mov    %edi,-0xc(%rbp)
mov    -0xc(%rbp),%eax
mov    %eax,-0x10(%rbp)
test   %eax,%eax
je     115e <pkt_name+0x5e>
jmp    111a <pkt_name+0x1a>
mov    -0x10(%rbp),%eax
sub    $0x10,%eax
je     116e <pkt_name+0x6e>
jmp    112b <pkt_name+0x2b>
mov    -0x10(%rbp),%eax
sub    $0x20,%eax
je     117e <pkt_name+0x7e>
jmp    113c <pkt_name+0x3c>
mov    -0x10(%rbp),%eax
sub    $0x30,%eax
je     118e <pkt_name+0x8e>
jmp    114d <pkt_name+0x4d>
mov    -0x10(%rbp),%eax
sub    $0x40,%eax
je     119e <pkt_name+0x9e>
jmp    11ae <pkt_name+0xae>
lea    0xe9b(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11b9 <pkt_name+0xb9>
lea    0xe92(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11b9 <pkt_name+0xb9>
lea    0xe86(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11b9 <pkt_name+0xb9>
lea    0xe7b(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11b9 <pkt_name+0xb9>
lea    0xe74(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11b9 <pkt_name+0xb9>
lea    0xe6a(%rip),%rax
mov    %rax,-0x8(%rbp)
mov    -0x8(%rbp),%rax
pop    %rbp
ret

x86 assembly (clang, -O2):
<pkt_name>:
rol    $0x1c,%edi
cmp    $0x4,%edi
ja     111a <pkt_name+0x1a>
movslq %edi,%rax
lea    0xf16(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
ret
lea    0xefe(%rip),%rax
ret

LLVM IR (-O0):
@.str = [7 x i8] c"STATUS\00"
@.str.1 = [4 x i8] c"GET\00"
@.str.2 = [5 x i8] c"POST\00"
@.str.3 = [9 x i8] c"CRITICAL\00"
@.str.4 = [6 x i8] c"ASYNC\00"
@.str.5 = [8 x i8] c"UNKNOWN\00"
define i8* @pkt_name(i32 %0) {
%2 = alloca i8*
%3 = alloca i32
store i32 %0, i32* %3
%4 = load i32, i32* %3
switch i32 %4, label %10 [
i32 0, label %5
i32 16, label %6
i32 32, label %7
i32 48, label %8
i32 64, label %9
]
5: ; preds = %1
store i8* getelementptr inbounds ([7 x i8], [7 x i8]* @.str, i64 0, i64 0), i8** %2
br label %11
6: ; preds = %1
store i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.1, i64 0, i64 0), i8** %2
br label %11
7: ; preds = %1
store i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.2, i64 0, i64 0), i8** %2
br label %11
8: ; preds = %1
store i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.3, i64 0, i64 0), i8** %2
br label %11
9: ; preds = %1
store i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.4, i64 0, i64 0), i8** %2
br label %11
10: ; preds = %1
store i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str.5, i64 0, i64 0), i8** %2
br label %11
11: ; preds = %10, %9, %8, %7, %6, %5
%12 = load i8*, i8** %2
ret i8* %12
}

LLVM IR (-O2):
@.str = [7 x i8] c"STATUS\00"
@.str.1 = [4 x i8] c"GET\00"
@.str.2 = [5 x i8] c"POST\00"
@.str.3 = [9 x i8] c"CRITICAL\00"
@.str.4 = [6 x i8] c"ASYNC\00"
@.str.5 = [8 x i8] c"UNKNOWN\00"
@reltable.pkt_name = [5 x i32] [i32 trunc (i64 sub (i64 ptrtoint ([7 x i8]* @.str to i64), i64 ptrtoint ([5 x i32]* @reltable.pkt_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([4 x i8]* @.str.1 to i64), i64 ptrtoint ([5 x i32]* @reltable.pkt_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([5 x i8]* @.str.2 to i64), i64 ptrtoint ([5 x i32]* @reltable.pkt_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([9 x i8]* @.str.3 to i64), i64 ptrtoint ([5 x i32]* @reltable.pkt_name to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.4 to i64), i64 ptrtoint ([5 x i32]* @reltable.pkt_name to i64)) to i32)]
define i8* @pkt_name(i32 %0) {
%2 = tail call i32 @llvm.fshl.i32(i32 %0, i32 %0, i32 28)
%3 = icmp ult i32 %2, 5
br i1 %3, label %4, label %8
4: ; preds = %1
%5 = sext i32 %2 to i64
%6 = shl i64 %5, 2
%7 = call i8* @llvm.load.relative.i64(i8* bitcast ([5 x i32]* @reltable.pkt_name to i8*), i64 %6)
br label %8
8: ; preds = %1, %4
%9 = phi i8* [ %7, %4 ], [ getelementptr inbounds ([8 x i8], [8 x i8]* @.str.5, i64 0, i64 0), %1 ]
ret i8* %9
}