const char *utf8proc_errmsg(int errcode) {
  switch (errcode) {
  case -1:
    return "Memory for processing UTF-8 data could not be allocated.";
  case -2:
    return "UTF-8 string is too long to be processed.";
  case -3:
    return "Invalid UTF-8 string";
  case -4:
    return "Unassigned Unicode code point found in UTF-8 string.";
  case -5:
    return "Invalid options for UTF-8 processing chosen.";
  default:
    return "An unknown error occured while processing UTF-8 data.";
  }
}


x86 assembly (clang, -O0):
<utf8proc_errmsg>:
push   %rbp
mov    %rsp,%rbp
mov    %edi,-0xc(%rbp)
mov    -0xc(%rbp),%eax
add    $0x5,%eax
mov    %eax,%ecx
mov    %rcx,-0x18(%rbp)
sub    $0x4,%eax
ja     1180 <utf8proc_errmsg+0x80>
mov    -0x18(%rbp),%rax
lea    0xed9(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
jmp    *%rax
lea    0xedd(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    118b <utf8proc_errmsg+0x8b>
lea    0xf06(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    118b <utf8proc_errmsg+0x8b>
lea    0xf20(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    118b <utf8proc_errmsg+0x8b>
lea    0xf25(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    118b <utf8proc_errmsg+0x8b>
lea    0xf4a(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    118b <utf8proc_errmsg+0x8b>
lea    0xf67(%rip),%rax
mov    %rax,-0x8(%rbp)
mov    -0x8(%rbp),%rax
pop    %rbp
ret

x86 assembly (clang, -O2):
<utf8proc_errmsg>:
cmp    $0xfffffffb,%edi
jb     111a <utf8proc_errmsg+0x1a>
add    $0x5,%edi
movslq %edi,%rax
lea    0xffe(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
ret
lea    0xfb9(%rip),%rax
ret

LLVM IR (-O0):
@.str = [57 x i8] c"Memory for processing UTF-8 data could not be allocated.\00"
@.str.1 = [42 x i8] c"UTF-8 string is too long to be processed.\00"
@.str.2 = [21 x i8] c"Invalid UTF-8 string\00"
@.str.3 = [53 x i8] c"Unassigned Unicode code point found in UTF-8 string.\00"
@.str.4 = [45 x i8] c"Invalid options for UTF-8 processing chosen.\00"
@.str.5 = [54 x i8] c"An unknown error occured while processing UTF-8 data.\00"
define i8* @utf8proc_errmsg(i32 %0) {
%2 = alloca i8*
%3 = alloca i32
store i32 %0, i32* %3
%4 = load i32, i32* %3
switch i32 %4, label %10 [
i32 -1, label %5
i32 -2, label %6
i32 -3, label %7
i32 -4, label %8
i32 -5, label %9
]
5: ; preds = %1
store i8* getelementptr inbounds ([57 x i8], [57 x i8]* @.str, i64 0, i64 0), i8** %2
br label %11
6: ; preds = %1
store i8* getelementptr inbounds ([42 x i8], [42 x i8]* @.str.1, i64 0, i64 0), i8** %2
br label %11
7: ; preds = %1
store i8* getelementptr inbounds ([21 x i8], [21 x i8]* @.str.2, i64 0, i64 0), i8** %2
br label %11
8: ; preds = %1
store i8* getelementptr inbounds ([53 x i8], [53 x i8]* @.str.3, i64 0, i64 0), i8** %2
br label %11
9: ; preds = %1
store i8* getelementptr inbounds ([45 x i8], [45 x i8]* @.str.4, i64 0, i64 0), i8** %2
br label %11
10: ; preds = %1
store i8* getelementptr inbounds ([54 x i8], [54 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 = [57 x i8] c"Memory for processing UTF-8 data could not be allocated.\00"
@.str.1 = [42 x i8] c"UTF-8 string is too long to be processed.\00"
@.str.2 = [21 x i8] c"Invalid UTF-8 string\00"
@.str.3 = [53 x i8] c"Unassigned Unicode code point found in UTF-8 string.\00"
@.str.4 = [45 x i8] c"Invalid options for UTF-8 processing chosen.\00"
@.str.5 = [54 x i8] c"An unknown error occured while processing UTF-8 data.\00"
@reltable.utf8proc_errmsg = [5 x i32] [i32 trunc (i64 sub (i64 ptrtoint ([45 x i8]* @.str.4 to i64), i64 ptrtoint ([5 x i32]* @reltable.utf8proc_errmsg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([53 x i8]* @.str.3 to i64), i64 ptrtoint ([5 x i32]* @reltable.utf8proc_errmsg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([21 x i8]* @.str.2 to i64), i64 ptrtoint ([5 x i32]* @reltable.utf8proc_errmsg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([42 x i8]* @.str.1 to i64), i64 ptrtoint ([5 x i32]* @reltable.utf8proc_errmsg to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([57 x i8]* @.str to i64), i64 ptrtoint ([5 x i32]* @reltable.utf8proc_errmsg to i64)) to i32)]
define i8* @utf8proc_errmsg(i32 %0) {
%2 = icmp ugt i32 %0, -6
br i1 %2, label %3, label %8
3: ; preds = %1
%4 = add i32 %0, 5
%5 = sext i32 %4 to i64
%6 = shl i64 %5, 2
%7 = call i8* @llvm.load.relative.i64(i8* bitcast ([5 x i32]* @reltable.utf8proc_errmsg to i8*), i64 %6)
br label %8
8: ; preds = %1, %3
%9 = phi i8* [ %7, %3 ], [ getelementptr inbounds ([54 x i8], [54 x i8]* @.str.5, i64 0, i64 0), %1 ]
ret i8* %9
}