src/test/mir-opt/if-condition-int.rs

   1 // compile-flags: -O
   2 // EMIT_MIR if_condition_int.opt_u32.SimplifyComparisonIntegral.diff
   3 // EMIT_MIR if_condition_int.opt_negative.SimplifyComparisonIntegral.diff
   4 // EMIT_MIR if_condition_int.opt_char.SimplifyComparisonIntegral.diff
   5 // EMIT_MIR if_condition_int.opt_i8.SimplifyComparisonIntegral.diff
   6 // EMIT_MIR if_condition_int.dont_opt_bool.SimplifyComparisonIntegral.diff
   7 // EMIT_MIR if_condition_int.opt_multiple_ifs.SimplifyComparisonIntegral.diff
   8 // EMIT_MIR if_condition_int.dont_remove_comparison.SimplifyComparisonIntegral.diff
   9 // EMIT_MIR if_condition_int.dont_opt_floats.SimplifyComparisonIntegral.diff
  10
  11 fn opt_u32(x: u32) -> u32 {
  12     if x == 42 { 0 } else { 1 }
  13 }
  14
  15 // don't opt: it is already optimal to switch on the bool
  16 fn dont_opt_bool(x: bool) -> u32 {
  17     if x { 0 } else { 1 }
  18 }
  19
  20 fn opt_char(x: char) -> u32 {
  21     if x == 'x' { 0 } else { 1 }
  22 }
  23
  24 fn opt_i8(x: i8) -> u32 {
  25     if x == 42 { 0 } else { 1 }
  26 }
  27
  28 fn opt_negative(x: i32) -> u32 {
  29     if x == -42 { 0 } else { 1 }
  30 }
  31
  32 fn opt_multiple_ifs(x: u32) -> u32 {
  33     if x == 42 {
  34         0
  35     } else if x != 21 {
  36         1
  37     } else {
  38         2
  39     }
  40 }
  41
  42 // test that we optimize, but do not remove the b statement, as that is used later on
  43 fn dont_remove_comparison(a: i8) -> i32 {
  44     let b = a == 17;
  45     match b {
  46         false => 10 + b as i32,
  47         true => 100 + b as i32,
  48     }
  49 }
  50
  51 // test that we do not optimize on floats
  52 fn dont_opt_floats(a: f32) -> i32 {
  53     if a == -42.0 { 0 } else { 1 }
  54 }
  55
  56 fn main() {
  57     opt_u32(0);
  58     opt_char('0');
  59     opt_i8(22);
  60     dont_opt_bool(false);
  61     opt_negative(0);
  62     opt_multiple_ifs(0);
  63     dont_remove_comparison(11);
  64     dont_opt_floats(1.0);
  65 }