add regression tests for gvn of local arrays

Author: tesuji

tests/mir-opt/const_array_locals.main.GVN.diff

@@ -0,0 +1,97 @@
+- // MIR for `main` before GVN
++ // MIR for `main` after GVN
+  
+  fn main() -> () {
+      let mut _0: ();
+      let _1: [i32; 32];
+      let mut _4: [i32; 12];
+      let mut _5: [i32; 12];
+      let mut _7: &[i32; 32];
+      let _8: [i32; 32];
+      let _9: ();
+      let mut _10: [u16; 32];
+      let mut _12: [f32; 8];
+      let _13: [[i32; 3]; 3];
+      let mut _14: [i32; 3];
+      let mut _15: [i32; 3];
+      let mut _16: [i32; 3];
+      scope 1 {
+          debug _arr => _1;
+          let _2: [i32; 32];
+          scope 2 {
+              debug _barr => _2;
+              let _3: [[i32; 12]; 2];
+              scope 3 {
+                  debug _foo => _3;
+                  let _6: [i32; 32];
+                  let mut _17: &[i32; 32];
+                  scope 4 {
+                      debug _darr => _6;
+                      let _11: F32x8;
+                      scope 5 {
+                          debug _f => _11;
+                      }
+                  }
+              }
+          }
+      }
+  
+      bb0: {
+-         StorageLive(_1);
++         nop;
+          _1 = [const 255_i32, const 105_i32, const 15_i32, const 39_i32, const 62_i32, const 251_i32, const 191_i32, const 178_i32, const 9_i32, const 4_i32, const 56_i32, const 221_i32, const 193_i32, const 164_i32, const 194_i32, const 197_i32, const 6_i32, const 243_i32, const 218_i32, const 171_i32, const 87_i32, const 247_i32, const 104_i32, const 159_i32, const 22_i32, const 157_i32, const 105_i32, const 31_i32, const 96_i32, const 173_i32, const 50_i32, const 1_i32];
+          StorageLive(_2);
+-         _2 = [const 255_i32, const 105_i32, const 15_i32, const 39_i32, const 62_i32, const 251_i32, const 191_i32, const 178_i32, const 9_i32, const 4_i32, const 56_i32, const 221_i32, const 193_i32, const 164_i32, const 194_i32, const 197_i32, const 6_i32, const 243_i32, const 218_i32, const 171_i32, const 87_i32, const 247_i32, const 104_i32, const 159_i32, const 22_i32, const 157_i32, const 105_i32, const 31_i32, const 96_i32, const 173_i32, const 50_i32, const 1_i32];
++         _2 = _1;
+          StorageLive(_3);
+          StorageLive(_4);
+          _4 = [const 255_i32, const 105_i32, const 15_i32, const 39_i32, const 62_i32, const 251_i32, const 191_i32, const 178_i32, const 9_i32, const 4_i32, const 56_i32, const 221_i32];
+          StorageLive(_5);
+          _5 = [const 193_i32, const 164_i32, const 194_i32, const 197_i32, const 6_i32, const 243_i32, const 218_i32, const 171_i32, const 87_i32, const 247_i32, const 104_i32, const 42_i32];
+          _3 = [move _4, move _5];
+          StorageDead(_5);
+          StorageDead(_4);
+          StorageLive(_6);
+          StorageLive(_7);
+          _17 = const main::promoted[0];
+          _7 = &(*_17);
+-         _6 = (*_7);
++         _6 = (*_17);
+          StorageDead(_7);
+          StorageLive(_9);
+          StorageLive(_10);
+          _10 = [const 255_u16, const 105_u16, const 15_u16, const 39_u16, const 62_u16, const 251_u16, const 191_u16, const 178_u16, const 9_u16, const 4_u16, const 56_u16, const 221_u16, const 193_u16, const 164_u16, const 194_u16, const 197_u16, const 6_u16, const 243_u16, const 218_u16, const 171_u16, const 87_u16, const 247_u16, const 104_u16, const 159_u16, const 22_u16, const 157_u16, const 105_u16, const 31_u16, const 96_u16, const 173_u16, const 50_u16, const 1_u16];
+          _9 = consume(move _10) -> [return: bb1, unwind continue];
+      }
+  
+      bb1: {
+          StorageDead(_10);
+          StorageDead(_9);
+          StorageLive(_11);
+          StorageLive(_12);
+          _12 = [const 1f32, const 2f32, const 3f32, const 1f32, const 1f32, const 1f32, const 1f32, const 42f32];
+          _11 = F32x8(move _12);
+          StorageDead(_12);
+          StorageLive(_13);
+          StorageLive(_14);
+          _14 = [const 1_i32, const 0_i32, const 0_i32];
+          StorageLive(_15);
+          _15 = [const 0_i32, const 1_i32, const 0_i32];
+          StorageLive(_16);
+          _16 = [const 0_i32, const 0_i32, const 1_i32];
+          _13 = [move _14, move _15, move _16];
+          StorageDead(_16);
+          StorageDead(_15);
+          StorageDead(_14);
+          StorageDead(_13);
+          _0 = const ();
+          StorageDead(_11);
+          StorageDead(_6);
+          StorageDead(_3);
+          StorageDead(_2);
+-         StorageDead(_1);
++         nop;
+          return;
+      }
+  }
+  

tests/mir-opt/const_array_locals.rs

@@ -0,0 +1,44 @@
+//@ test-mir-pass: GVN
+#![feature(repr_simd)]
+
+#[repr(simd)]
+struct F32x8([f32; 8]);
+
+// EMIT_MIR const_array_locals.main.GVN.diff
+// CHECK-LABEL: fn main(
+#[rustfmt::skip]
+pub fn main() {
+    let _arr = [
+        255, 105, 15, 39, 62, 251, 191, 178, 9, 4, 56, 221,
+        193, 164, 194, 197, 6, 243, 218, 171, 87, 247, 104,
+        159, 22, 157, 105, 31, 96, 173, 50, 1,
+    ];
+    // duplicate item
+    let _barr = [
+        255, 105, 15, 39, 62, 251, 191, 178, 9, 4, 56, 221,
+        193, 164, 194, 197, 6, 243, 218, 171, 87, 247, 104,
+        159, 22, 157, 105, 31, 96, 173, 50, 1,
+    ];
+    let _foo = [
+        [255, 105, 15, 39, 62, 251, 191, 178, 9, 4, 56, 221],
+        [193, 164, 194, 197, 6, 243, 218, 171, 87, 247, 104, 42],
+    ];
+    let _darr = *&[
+        255, 105, 15, 39, 62, 251, 191, 178, 9, 4, 56, 221,
+        193, 164, 194, 197, 6, 243, 218, 171, 87, 247, 104,
+        159, 22, 157, 105, 31, 96, 173, 50, 1,
+    ];
+
+    consume([255, 105, 15, 39, 62, 251, 191, 178, 9, 4, 56, 221,
+        193, 164, 194, 197, 6, 243, 218, 171, 87, 247, 104,
+        159, 22, 157, 105, 31, 96, 173, 50, 1,]);
+
+    let _f = F32x8([1.0, 2.0, 3.0, 1.0, 1.0, 1.0, 1.0, 42.0]);
+
+    // ice
+    [[1, 0, 0], [0, 1, 0], [0, 0, 1]]; // 2D array
+}
+
+fn consume(_arr: [u16; 32]) {
+    unimplemented!()
+}