char *error_msg(int e) {
  switch (e) {
  case 0:
    return "Success";
  case 1:
    return "Failure";
  case 2:
    return "Not implemented";
  case 3:
    return "Unable to allocate memory";
  case 4:
    return "(websocket) Reserved bit set";
  case 5:
    return "(websocket) Bad opcode";
  case 6:
    return "(websocket) Unmasked client data";
  case 7:
    return "(websocket) Connection close requested";
  case 8:
    return "(websocket) Fragmented control frame";
  case 9:
    return "(websocket) Unexpected continuation frame";
  case 10:
    return "(websocket) Unexpected pong frame";
  case 11:
    return "(librecast) Operation on null context";
  case 12:
    return "(librecast) No such channel";
  case 13:
    return "(librecast) No channel selected";
  case 14:
    return "(librecast) Unable to create channel";
  case 15:
    return "(librecast) Unable to join channel";
  case 16:
    return "(librecast) Listen failed on socket";
  case 17:
    return "(librecast) No socket";
  case 18:
    return "(librecast) Invalid opcode";
  case 19:
    return "(librecast) Unable to create socket";
  case 20:
    return "(librecast) Invalid socket id";
  case 21:
    return "(librecast) Invalid parameters to function";
  }
  return "Unknown error";
}


x86 assembly (clang, -O0):
<error_msg>:
push   %rbp
mov    %rsp,%rbp
mov    %edi,-0xc(%rbp)
mov    -0xc(%rbp),%eax
mov    %rax,-0x18(%rbp)
sub    $0x15,%rax
ja     128c <error_msg+0x18c>
mov    -0x18(%rbp),%rax
lea    0xedd(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
jmp    *%rax
lea    0xf25(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xf1d(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xf15(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xf15(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xf1f(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xf2c(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xf33(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xf44(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xf5b(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xf70(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xf8a(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xf9c(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xfb2(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xfbe(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xfce(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xfe3(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0xff6(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0x100a(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0x1010(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0x101b(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0x102f(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0x103d(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    1297 <error_msg+0x197>
lea    0x1058(%rip),%rax
mov    %rax,-0x8(%rbp)
mov    -0x8(%rbp),%rax
pop    %rbp
ret

x86 assembly (clang, -O2):
<error_msg>:
cmp    $0x15,%edi
ja     1117 <error_msg+0x17>
movslq %edi,%rax
lea    0x1195(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
ret
lea    0x1175(%rip),%rax
ret

LLVM IR (-O0):
@.str = [8 x i8] c"Success\00"
@.str.1 = [8 x i8] c"Failure\00"
@.str.2 = [16 x i8] c"Not implemented\00"
@.str.3 = [26 x i8] c"Unable to allocate memory\00"
@.str.4 = [29 x i8] c"(websocket) Reserved bit set\00"
@.str.5 = [23 x i8] c"(websocket) Bad opcode\00"
@.str.6 = [33 x i8] c"(websocket) Unmasked client data\00"
@.str.7 = [39 x i8] c"(websocket) Connection close requested\00"
@.str.8 = [37 x i8] c"(websocket) Fragmented control frame\00"
@.str.9 = [42 x i8] c"(websocket) Unexpected continuation frame\00"
@.str.10 = [34 x i8] c"(websocket) Unexpected pong frame\00"
@.str.11 = [38 x i8] c"(librecast) Operation on null context\00"
@.str.12 = [28 x i8] c"(librecast) No such channel\00"
@.str.13 = [32 x i8] c"(librecast) No channel selected\00"
@.str.14 = [37 x i8] c"(librecast) Unable to create channel\00"
@.str.15 = [35 x i8] c"(librecast) Unable to join channel\00"
@.str.16 = [36 x i8] c"(librecast) Listen failed on socket\00"
@.str.17 = [22 x i8] c"(librecast) No socket\00"
@.str.18 = [27 x i8] c"(librecast) Invalid opcode\00"
@.str.19 = [36 x i8] c"(librecast) Unable to create socket\00"
@.str.20 = [30 x i8] c"(librecast) Invalid socket id\00"
@.str.21 = [43 x i8] c"(librecast) Invalid parameters to function\00"
@.str.22 = [14 x i8] c"Unknown error\00"
define i8* @error_msg(i32 %0) {
%2 = alloca i8*
%3 = alloca i32
store i32 %0, i32* %3
%4 = load i32, i32* %3
switch i32 %4, label %27 [
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
i32 21, label %26
]
5: ; preds = %1
store i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str, i64 0, i64 0), i8** %2
br label %28
6: ; preds = %1
store i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str.1, i64 0, i64 0), i8** %2
br label %28
7: ; preds = %1
store i8* getelementptr inbounds ([16 x i8], [16 x i8]* @.str.2, i64 0, i64 0), i8** %2
br label %28
8: ; preds = %1
store i8* getelementptr inbounds ([26 x i8], [26 x i8]* @.str.3, i64 0, i64 0), i8** %2
br label %28
9: ; preds = %1
store i8* getelementptr inbounds ([29 x i8], [29 x i8]* @.str.4, i64 0, i64 0), i8** %2
br label %28
10: ; preds = %1
store i8* getelementptr inbounds ([23 x i8], [23 x i8]* @.str.5, i64 0, i64 0), i8** %2
br label %28
11: ; preds = %1
store i8* getelementptr inbounds ([33 x i8], [33 x i8]* @.str.6, i64 0, i64 0), i8** %2
br label %28
12: ; preds = %1
store i8* getelementptr inbounds ([39 x i8], [39 x i8]* @.str.7, i64 0, i64 0), i8** %2
br label %28
13: ; preds = %1
store i8* getelementptr inbounds ([37 x i8], [37 x i8]* @.str.8, i64 0, i64 0), i8** %2
br label %28
14: ; preds = %1
store i8* getelementptr inbounds ([42 x i8], [42 x i8]* @.str.9, i64 0, i64 0), i8** %2
br label %28
15: ; preds = %1
store i8* getelementptr inbounds ([34 x i8], [34 x i8]* @.str.10, i64 0, i64 0), i8** %2
br label %28
16: ; preds = %1
store i8* getelementptr inbounds ([38 x i8], [38 x i8]* @.str.11, i64 0, i64 0), i8** %2
br label %28
17: ; preds = %1
store i8* getelementptr inbounds ([28 x i8], [28 x i8]* @.str.12, i64 0, i64 0), i8** %2
br label %28
18: ; preds = %1
store i8* getelementptr inbounds ([32 x i8], [32 x i8]* @.str.13, i64 0, i64 0), i8** %2
br label %28
19: ; preds = %1
store i8* getelementptr inbounds ([37 x i8], [37 x i8]* @.str.14, i64 0, i64 0), i8** %2
br label %28
20: ; preds = %1
store i8* getelementptr inbounds ([35 x i8], [35 x i8]* @.str.15, i64 0, i64 0), i8** %2
br label %28
21: ; preds = %1
store i8* getelementptr inbounds ([36 x i8], [36 x i8]* @.str.16, i64 0, i64 0), i8** %2
br label %28
22: ; preds = %1
store i8* getelementptr inbounds ([22 x i8], [22 x i8]* @.str.17, i64 0, i64 0), i8** %2
br label %28
23: ; preds = %1
store i8* getelementptr inbounds ([27 x i8], [27 x i8]* @.str.18, i64 0, i64 0), i8** %2
br label %28
24: ; preds = %1
store i8* getelementptr inbounds ([36 x i8], [36 x i8]* @.str.19, i64 0, i64 0), i8** %2
br label %28
25: ; preds = %1
store i8* getelementptr inbounds ([30 x i8], [30 x i8]* @.str.20, i64 0, i64 0), i8** %2
br label %28
26: ; preds = %1
store i8* getelementptr inbounds ([43 x i8], [43 x i8]* @.str.21, i64 0, i64 0), i8** %2
br label %28
27: ; preds = %1
store i8* getelementptr inbounds ([14 x i8], [14 x i8]* @.str.22, i64 0, i64 0), i8** %2
br label %28
28: ; preds = %27, %26, %25, %24, %23, %22, %21, %20, %19, %18, %17, %16, %15, %14, %13, %12, %11, %10, %9, %8, %7, %6, %5
%29 = load i8*, i8** %2
ret i8* %29
}

LLVM IR (-O2):
@.str = [8 x i8] c"Success\00"
@.str.1 = [8 x i8] c"Failure\00"
@.str.2 = [16 x i8] c"Not implemented\00"
@.str.3 = [26 x i8] c"Unable to allocate memory\00"
@.str.4 = [29 x i8] c"(websocket) Reserved bit set\00"
@.str.5 = [23 x i8] c"(websocket) Bad opcode\00"
@.str.6 = [33 x i8] c"(websocket) Unmasked client data\00"
@.str.7 = [39 x i8] c"(websocket) Connection close requested\00"
@.str.8 = [37 x i8] c"(websocket) Fragmented control frame\00"
@.str.9 = [42 x i8] c"(websocket) Unexpected continuation frame\00"
@.str.10 = [34 x i8] c"(websocket) Unexpected pong frame\00"
@.str.11 = [38 x i8] c"(librecast) Operation on null context\00"
@.str.12 = [28 x i8] c"(librecast) No such channel\00"
@.str.13 = [32 x i8] c"(librecast) No channel selected\00"
@.str.14 = [37 x i8] c"(librecast) Unable to create channel\00"
@.str.15 = [35 x i8] c"(librecast) Unable to join channel\00"
@.str.16 = [36 x i8] c"(librecast) Listen failed on socket\00"
@.str.17 = [22 x i8] c"(librecast) No socket\00"
@.str.18 = [27 x i8] c"(librecast) Invalid opcode\00"
@.str.19 = [36 x i8] c"(librecast) Unable to create socket\00"
@.str.20 = [30 x i8] c"(librecast) Invalid socket id\00"
@.str.21 = [43 x i8] c"(librecast) Invalid parameters to function\00"
@.str.22 = [14 x i8] c"Unknown error\00"
@reltable.error_msg = [22 x i32] [i32 trunc (i64 sub (i64 ptrtoint ([8 x i8]* @.str to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([8 x i8]* @.str.1 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([16 x i8]* @.str.2 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([26 x i8]* @.str.3 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([29 x i8]* @.str.4 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([23 x i8]* @.str.5 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([33 x i8]* @.str.6 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([39 x i8]* @.str.7 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([37 x i8]* @.str.8 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([42 x i8]* @.str.9 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([34 x i8]* @.str.10 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([38 x i8]* @.str.11 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([28 x i8]* @.str.12 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([32 x i8]* @.str.13 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([37 x i8]* @.str.14 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([35 x i8]* @.str.15 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([36 x i8]* @.str.16 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([22 x i8]* @.str.17 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([27 x i8]* @.str.18 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([36 x i8]* @.str.19 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([30 x i8]* @.str.20 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([43 x i8]* @.str.21 to i64), i64 ptrtoint ([22 x i32]* @reltable.error_msg to i64)) to i32)]
define i8* @error_msg(i32 %0) {
%2 = icmp ult i32 %0, 22
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 ([22 x i32]* @reltable.error_msg to i8*), i64 %5)
br label %7
7: ; preds = %1, %3
%8 = phi i8* [ %6, %3 ], [ getelementptr inbounds ([14 x i8], [14 x i8]* @.str.22, i64 0, i64 0), %1 ]
ret i8* %8
}