add regression test

Author: tesuji

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

@@ -0,0 +1,44 @@
+- // MIR for `main` before GVN
++ // MIR for `main` after GVN
+  
+  fn main() -> () {
+      let mut _0: ();
+      let _1: [i32; 32];
+      let mut _4: &[i32; 32];
+      let _5: [i32; 32];
+      scope 1 {
+          debug _arr => _1;
+          let _2: [i32; 32];
+          scope 2 {
+              debug _barr => _2;
+              let _3: [i32; 32];
+              let mut _6: &[i32; 32];
+              scope 3 {
+                  debug _darr => _3;
+              }
+          }
+      }
+  
+      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);
+          _6 = const main::promoted[0];
+          _4 = &(*_6);
+-         _3 = (*_4);
++         _3 = (*_6);
+          StorageDead(_4);
+          _0 = const ();
+          StorageDead(_3);
+          StorageDead(_2);
+-         StorageDead(_1);
++         nop;
+          return;
+      }
+  }
+  

tests/mir-opt/const_array_locals.rs

@@ -0,0 +1,46 @@
+//@ 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() {
+    // CHECK: let [[array_lit:_.*]]: [i32; 32];
+    // CHECK:     debug _arr => [[arr:_.*]];
+
+    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,
+    ];
+    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, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0]);
+
+    // // ice
+    // [[1, 0, 0], [0, 1, 0], [0, 0, 1]]; // 2D array
+}
+
+// fn consume(_arr: [u16; 32]) {
+//     unimplemented!()
+// }