const char *rev_exit(short vdir) {
  switch (vdir) {
  default:
    return "somewhere";
  case 0:
    return "the south";
  case 1:
    return "the west";
  case 2:
    return "the north";
  case 3:
    return "the east";
  case 4:
    return "below";
  case 5:
    return "above";
  case 6:
    return "the southwest";
  case 7:
    return "the southeast";
  case 8:
    return "the northwest";
  case 9:
    return "the northeast";
  }
}


x86 assembly (clang, -O0):
<rev_exit>:
push   %rbp
mov    %rsp,%rbp
mov    %di,%ax
mov    %ax,-0xa(%rbp)
movswl -0xa(%rbp),%eax
mov    %eax,%ecx
mov    %rcx,-0x18(%rbp)
sub    $0x9,%eax
ja     1132 <rev_exit+0x32>
mov    -0x18(%rbp),%rax
lea    0xed7(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
jmp    *%rax
lea    0xeef(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11dd <rev_exit+0xdd>
lea    0xee9(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11dd <rev_exit+0xdd>
lea    0xee3(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11dd <rev_exit+0xdd>
lea    0xedc(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11dd <rev_exit+0xdd>
lea    0xed6(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11dd <rev_exit+0xdd>
lea    0xecf(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11dd <rev_exit+0xdd>
lea    0xec5(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11dd <rev_exit+0xdd>
lea    0xebb(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11dd <rev_exit+0xdd>
lea    0xeb9(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11dd <rev_exit+0xdd>
lea    0xeb7(%rip),%rax
mov    %rax,-0x8(%rbp)
jmp    11dd <rev_exit+0xdd>
lea    0xeb5(%rip),%rax
mov    %rax,-0x8(%rbp)
mov    -0x8(%rbp),%rax
pop    %rbp
ret

x86 assembly (clang, -O2):
<rev_exit>:
cmp    $0x9,%di
ja     1119 <rev_exit+0x19>
movswq %di,%rax
lea    0xf63(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
ret
lea    0xee0(%rip),%rax
ret

LLVM IR (-O0):
@.str = [10 x i8] c"somewhere\00"
@.str.1 = [10 x i8] c"the south\00"
@.str.2 = [9 x i8] c"the west\00"
@.str.3 = [10 x i8] c"the north\00"
@.str.4 = [9 x i8] c"the east\00"
@.str.5 = [6 x i8] c"below\00"
@.str.6 = [6 x i8] c"above\00"
@.str.7 = [14 x i8] c"the southwest\00"
@.str.8 = [14 x i8] c"the southeast\00"
@.str.9 = [14 x i8] c"the northwest\00"
@.str.10 = [14 x i8] c"the northeast\00"
define i8* @rev_exit(i16 signext %0) {
%2 = alloca i8*
%3 = alloca i16
store i16 %0, i16* %3
%4 = load i16, i16* %3
%5 = sext i16 %4 to i32
switch i32 %5, label %6 [
i32 0, label %7
i32 1, label %8
i32 2, label %9
i32 3, label %10
i32 4, label %11
i32 5, label %12
i32 6, label %13
i32 7, label %14
i32 8, label %15
i32 9, label %16
]
6: ; preds = %1
store i8* getelementptr inbounds ([10 x i8], [10 x i8]* @.str, i64 0, i64 0), i8** %2
br label %17
7: ; preds = %1
store i8* getelementptr inbounds ([10 x i8], [10 x i8]* @.str.1, i64 0, i64 0), i8** %2
br label %17
8: ; preds = %1
store i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.2, i64 0, i64 0), i8** %2
br label %17
9: ; preds = %1
store i8* getelementptr inbounds ([10 x i8], [10 x i8]* @.str.3, i64 0, i64 0), i8** %2
br label %17
10: ; preds = %1
store i8* getelementptr inbounds ([9 x i8], [9 x i8]* @.str.4, i64 0, i64 0), i8** %2
br label %17
11: ; preds = %1
store i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.5, i64 0, i64 0), i8** %2
br label %17
12: ; preds = %1
store i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.6, i64 0, i64 0), i8** %2
br label %17
13: ; preds = %1
store i8* getelementptr inbounds ([14 x i8], [14 x i8]* @.str.7, i64 0, i64 0), i8** %2
br label %17
14: ; preds = %1
store i8* getelementptr inbounds ([14 x i8], [14 x i8]* @.str.8, i64 0, i64 0), i8** %2
br label %17
15: ; preds = %1
store i8* getelementptr inbounds ([14 x i8], [14 x i8]* @.str.9, i64 0, i64 0), i8** %2
br label %17
16: ; preds = %1
store i8* getelementptr inbounds ([14 x i8], [14 x i8]* @.str.10, i64 0, i64 0), i8** %2
br label %17
17: ; preds = %16, %15, %14, %13, %12, %11, %10, %9, %8, %7, %6
%18 = load i8*, i8** %2
ret i8* %18
}

LLVM IR (-O2):
@.str = [10 x i8] c"somewhere\00"
@.str.1 = [10 x i8] c"the south\00"
@.str.2 = [9 x i8] c"the west\00"
@.str.3 = [10 x i8] c"the north\00"
@.str.4 = [9 x i8] c"the east\00"
@.str.5 = [6 x i8] c"below\00"
@.str.6 = [6 x i8] c"above\00"
@.str.7 = [14 x i8] c"the southwest\00"
@.str.8 = [14 x i8] c"the southeast\00"
@.str.9 = [14 x i8] c"the northwest\00"
@.str.10 = [14 x i8] c"the northeast\00"
@reltable.rev_exit = [10 x i32] [i32 trunc (i64 sub (i64 ptrtoint ([10 x i8]* @.str.1 to i64), i64 ptrtoint ([10 x i32]* @reltable.rev_exit to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([9 x i8]* @.str.2 to i64), i64 ptrtoint ([10 x i32]* @reltable.rev_exit to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([10 x i8]* @.str.3 to i64), i64 ptrtoint ([10 x i32]* @reltable.rev_exit to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([9 x i8]* @.str.4 to i64), i64 ptrtoint ([10 x i32]* @reltable.rev_exit to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.5 to i64), i64 ptrtoint ([10 x i32]* @reltable.rev_exit to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([6 x i8]* @.str.6 to i64), i64 ptrtoint ([10 x i32]* @reltable.rev_exit to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([14 x i8]* @.str.7 to i64), i64 ptrtoint ([10 x i32]* @reltable.rev_exit to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([14 x i8]* @.str.8 to i64), i64 ptrtoint ([10 x i32]* @reltable.rev_exit to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([14 x i8]* @.str.9 to i64), i64 ptrtoint ([10 x i32]* @reltable.rev_exit to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint ([14 x i8]* @.str.10 to i64), i64 ptrtoint ([10 x i32]* @reltable.rev_exit to i64)) to i32)]
define i8* @rev_exit(i16 signext %0) {
%2 = icmp ult i16 %0, 10
br i1 %2, label %3, label %7
3: ; preds = %1
%4 = sext i16 %0 to i64
%5 = shl i64 %4, 2
%6 = call i8* @llvm.load.relative.i64(i8* bitcast ([10 x i32]* @reltable.rev_exit to i8*), i64 %5)
br label %7
7: ; preds = %3, %1
%8 = phi i8* [ getelementptr inbounds ([10 x i8], [10 x i8]* @.str, i64 0, i64 0), %1 ], [ %6, %3 ]
ret i8* %8
}