char *yla_vm_error_message(int error_code) {
  switch (error_code) {
  case 0:
    return "No error";
  case (-1):
    return "No program code";
  case (-2):
    return "Code segment exceed";
  case (-3):
    return "Divide by zero";
  case (-4):
    return "Unknown command";
  case (-5):
    return "Empty stack";
  case (-6):
    return "Stack full_value";
  default:
    return "Unknown error";
  }
}


x86 assembly (clang, -O0):
<yla_vm_error_message>:
push   %rbp
mov    %rsp,%rbp
mov    %edi,-0xc(%rbp)
mov    -0xc(%rbp),%eax
add    $0x6,%eax
mov    %eax,%ecx
mov    %rcx,-0x18(%rbp)
sub    $0x6,%eax
ja     11a0 <yla_vm_error_message+0xa0>
mov    -0x18(%rbp),%rax
lea    0xed9(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
jmp    *%rax
lea    0xee5(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11ab <yla_vm_error_message+0xab>
lea    0xede(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11ab <yla_vm_error_message+0xab>
lea    0xede(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11ab <yla_vm_error_message+0xab>
lea    0xee2(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11ab <yla_vm_error_message+0xab>
lea    0xee1(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11ab <yla_vm_error_message+0xab>
lea    0xee1(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11ab <yla_vm_error_message+0xab>
lea    0xedd(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11ab <yla_vm_error_message+0xab>
lea    0xede(%rip),%rax
mov    %rax,-0x8(%rbp)
mov    -0x8(%rbp),%rax
pop    %rbp
ret

x86 assembly (clang, -O2):
<yla_vm_error_message>:
add    $0x6,%edi
cmp    $0x6,%edi
ja     111a <yla_vm_error_message+0x1a>
movslq %edi,%rax
lea    0xf66(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
ret
lea    0xf48(%rip),%rax
ret

LLVM IR (-O0):
@.str = [9 x i8] c"No error\00"
@.str.1 = [16 x i8] c"No program code\00"
@.str.2 = [20 x i8] c"Code segment exceed\00"
@.str.3 = [15 x i8] c"Divide by zero\00"
@.str.4 = [16 x i8] c"Unknown command\00"
@.str.5 = [12 x i8] c"Empty stack\00"
@.str.6 = [17 x i8] c"Stack full_value\00"
@.str.7 = [14 x i8] c"Unknown error\00"
define i8* @yla_vm_error_message(i32 %0) {
%2 = alloca i8*
%3 = alloca i32
store i32 %0, i32* %3
%4 = load i32, i32* %3
switch i32 %4, label %12 [
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
]
5: ; preds = %1
store i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str, i64 0, i64 0), i8** %2
br label %13
6: ; preds = %1
store i8* getelementptr inbounds ([16 x i8], [16 x i8]* @.str.1, i64 0, i64 0), i8** %2
br label %13
7: ; preds = %1
store i8* getelementptr inbounds ([20 x i8], [20 x i8]* @.str.2, i64 0, i64 0), i8** %2
br label %13
8: ; preds = %1
store i8* getelementptr inbounds ([15 x i8], [15 x i8]* @.str.3, i64 0, i64 0), i8** %2
br label %13
9: ; preds = %1
store i8* getelementptr inbounds ([16 x i8], [16 x i8]* @.str.4, i64 0, i64 0), i8** %2
br label %13
10: ; preds = %1
store i8* getelementptr inbounds ([12 x i8], [12 x i8]* @.str.5, i64 0, i64 0), i8** %2
br label %13
11: ; preds = %1
store i8* getelementptr inbounds ([17 x i8], [17 x i8]* @.str.6, i64 0, i64 0), i8** %2
br label %13
12: ; preds = %1
store i8* getelementptr inbounds ([14 x i8], [14 x i8]* @.str.7, i64 0, i64 0), i8** %2
br label %13
13: ; preds = %12, %11, %10, %9, %8, %7, %6, %5
%14 = load i8*, i8** %2
ret i8* %14
}

LLVM IR (-O2):
@.str = [9 x i8] c"No error\00"
@.str.1 = [16 x i8] c"No program code\00"
@.str.2 = [20 x i8] c"Code segment exceed\00"
@.str.3 = [15 x i8] c"Divide by zero\00"
@.str.4 = [16 x i8] c"Unknown command\00"
@.str.5 = [12 x i8] c"Empty stack\00"
@.str.6 = [17 x i8] c"Stack full_value\00"
@.str.7 = [14 x i8] c"Unknown error\00"
@reltable.yla_vm_error_message = [7 x i32] [i32 trunc (i64 sub (i64 ptrtoint ([17 x i8]* @.str.6 to i64), i64 ptrtoint ([7 x i32]* @reltable.yla_vm_error_message to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([12 x i8]* @.str.5 to i64), i64 ptrtoint ([7 x i32]* @reltable.yla_vm_error_message to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([16 x i8]* @.str.4 to i64), i64 ptrtoint ([7 x i32]* @reltable.yla_vm_error_message to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([15 x i8]* @.str.3 to i64), i64 ptrtoint ([7 x i32]* @reltable.yla_vm_error_message to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([20 x i8]* @.str.2 to i64), i64 ptrtoint ([7 x i32]* @reltable.yla_vm_error_message to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([16 x i8]* @.str.1 to i64), i64 ptrtoint ([7 x i32]* @reltable.yla_vm_error_message to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([9 x i8]* @.str to i64), i64 ptrtoint ([7 x i32]* @reltable.yla_vm_error_message to i64)) to i32)]
define i8* @yla_vm_error_message(i32 %0) {
%2 = add i32 %0, 6
%3 = icmp ult i32 %2, 7
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 ([7 x i32]* @reltable.yla_vm_error_message to i8*), i64 %6)
br label %8
8: ; preds = %1, %4
%9 = phi i8* [ %7, %4 ], [ getelementptr inbounds ([14 x i8], [14 x i8]* @.str.7, i64 0, i64 0), %1 ]
ret i8* %9
}