src/test/mir-opt/simplify-locals.rs

   1 // unit-test: SimplifyLocals
   2
   3 #![feature(box_syntax)]
   4 #![feature(thread_local)]
   5
   6 #[derive(Copy, Clone)]
   7 enum E {
   8      A,
   9      B,
  10 }
  11
  12 // EMIT_MIR simplify_locals.c.SimplifyLocals.diff
  13 fn c() {
  14     let bytes = [0u8; 10];
  15     // Unused cast
  16     let _: &[u8] = &bytes;
  17 }
  18
  19 // EMIT_MIR simplify_locals.d1.SimplifyLocals.diff
  20 fn d1() {
  21     // Unused set discriminant
  22     let _ = E::A;
  23 }
  24
  25 // EMIT_MIR simplify_locals.d2.SimplifyLocals.diff
  26 fn d2() {
  27     // Unused set discriminant
  28     {(10, E::A)}.1 = E::B;
  29 }
  30
  31 // EMIT_MIR simplify_locals.r.SimplifyLocals.diff
  32 fn r() {
  33     let mut a = 1;
  34     // Unused references
  35     let _ = &a;
  36     let _ = &mut a;
  37 }
  38
  39 #[thread_local] static mut X: u32 = 0;
  40
  41 // EMIT_MIR simplify_locals.t1.SimplifyLocals.diff
  42 fn t1() {
  43     // Unused thread local
  44     unsafe { X };
  45 }
  46
  47 // EMIT_MIR simplify_locals.t2.SimplifyLocals.diff
  48 fn t2() {
  49     // Unused thread local
  50     unsafe { &mut X };
  51 }
  52
  53 // EMIT_MIR simplify_locals.t3.SimplifyLocals.diff
  54 fn t3() {
  55     // Unused thread local
  56     unsafe { *&mut X };
  57 }
  58
  59 // EMIT_MIR simplify_locals.t4.SimplifyLocals.diff
  60 fn t4() -> u32 {
  61     // Used thread local
  62     unsafe { X + 1 }
  63 }
  64
  65 // EMIT_MIR simplify_locals.expose_addr.SimplifyLocals.diff
  66 fn expose_addr(p: *const usize) {
  67     // Used pointer to address cast. Has a side effect of exposing the provenance.
  68     p as usize;
  69 }
  70
  71 fn main() {
  72     c();
  73     d1();
  74     d2();
  75     r();
  76     t1();
  77     t2();
  78     t3();
  79     t4();
  80     expose_addr(&0);
  81 }