int get_num_ligne(int i) {
  switch (i) {
  case 0:
    return 1;
  case 1:
    return 2;
  case 2:
    return 3;
  case 3:
    return 4;
  case 4:
    return 5;
  case 5:
    return 6;
  case 6:
    return 7;
  case 7:
    return 7;
  case 8:
    return 8;
  case 9:
    return 9;
  case 10:
    return 10;
  case 11:
    return 10;
  case 12:
    return 11;
  case 13:
    return 12;
  case 14:
    return 13;
  case 15:
    return 13;
  case 16:
    return 14;
  default:
    return 0;
  }
}


x86 assembly (clang, -O0):
<get_num_ligne>:
push   %rbp
mov    %rsp,%rbp
mov    %edi,-0x8(%rbp)
mov    -0x8(%rbp),%eax
mov    %rax,-0x10(%rbp)
sub    $0x10,%rax
ja     11f8 <get_num_ligne+0xf8>
mov    -0x10(%rbp),%rax
lea    0xedd(%rip),%rcx
movslq (%rcx,%rax,4),%rax
add    %rcx,%rax
jmp    *%rax
movl   $0x1,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0x2,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0x3,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0x4,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0x5,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0x6,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0x7,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0x7,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0x8,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0x9,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0xa,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0xa,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0xb,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0xc,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0xd,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0xd,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0xe,-0x4(%rbp)
jmp    11ff <get_num_ligne+0xff>
movl   $0x0,-0x4(%rbp)
mov    -0x4(%rbp),%eax
pop    %rbp
ret

x86 assembly (clang, -O2):
<get_num_ligne>:
xor    %eax,%eax
cmp    $0x10,%edi
ja     1114 <get_num_ligne+0x14>
movslq %edi,%rax
lea    0xeef(%rip),%rcx
mov    (%rcx,%rax,4),%eax
ret

LLVM IR (-O0):
define i32 @get_num_ligne(i32 %0) {
%2 = alloca i32
%3 = alloca i32
store i32 %0, i32* %3
%4 = load i32, i32* %3
switch i32 %4, label %22 [
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
]
5: ; preds = %1
store i32 1, i32* %2
br label %23
6: ; preds = %1
store i32 2, i32* %2
br label %23
7: ; preds = %1
store i32 3, i32* %2
br label %23
8: ; preds = %1
store i32 4, i32* %2
br label %23
9: ; preds = %1
store i32 5, i32* %2
br label %23
10: ; preds = %1
store i32 6, i32* %2
br label %23
11: ; preds = %1
store i32 7, i32* %2
br label %23
12: ; preds = %1
store i32 7, i32* %2
br label %23
13: ; preds = %1
store i32 8, i32* %2
br label %23
14: ; preds = %1
store i32 9, i32* %2
br label %23
15: ; preds = %1
store i32 10, i32* %2
br label %23
16: ; preds = %1
store i32 10, i32* %2
br label %23
17: ; preds = %1
store i32 11, i32* %2
br label %23
18: ; preds = %1
store i32 12, i32* %2
br label %23
19: ; preds = %1
store i32 13, i32* %2
br label %23
20: ; preds = %1
store i32 13, i32* %2
br label %23
21: ; preds = %1
store i32 14, i32* %2
br label %23
22: ; preds = %1
store i32 0, i32* %2
br label %23
23: ; preds = %22, %21, %20, %19, %18, %17, %16, %15, %14, %13, %12, %11, %10, %9, %8, %7, %6, %5
%24 = load i32, i32* %2
ret i32 %24
}

LLVM IR (-O2):
@switch.table.get_num_ligne = [17 x i32] [i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 7, i32 8, i32 9, i32 10, i32 10, i32 11, i32 12, i32 13, i32 13, i32 14]
define i32 @get_num_ligne(i32 %0) {
%2 = icmp ult i32 %0, 17
br i1 %2, label %3, label %7
3: ; preds = %1
%4 = sext i32 %0 to i64
%5 = getelementptr inbounds [17 x i32], [17 x i32]* @switch.table.get_num_ligne, i64 0, i64 %4
%6 = load i32, i32* %5
br label %7
7: ; preds = %1, %3
%8 = phi i32 [ %6, %3 ], [ 0, %1 ]
ret i32 %8
}