[turbofan] Reduce (x & K) & K to x & K.

test/unittests/compiler/machine-operator-reducer-unittest.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/base/bits.h"
 #include "src/base/division-by-constant.h"
 #include "src/compiler/js-graph.h"
 #include "src/compiler/machine-operator-reducer.h"
 #include "src/compiler/typer.h"
 #include "test/unittests/compiler/graph-unittest.h"
@@ skipping 464 matching lines @@
         graph()->NewNode(machine()->TruncateInt64ToInt32(), Int64Constant(x)));
     ASSERT_TRUE(reduction.Changed());
     EXPECT_THAT(reduction.replacement(),
                 IsInt32Constant(bit_cast<int32_t>(
                     static_cast<uint32_t>(bit_cast<uint64_t>(x)))));
   }
 }
 
 
 // -----------------------------------------------------------------------------
+// Word32And
+
+
+TEST_F(MachineOperatorReducerTest, Word32AndWithWord32AndWithConstant) {
+  Node* const p0 = Parameter(0);
+
+  TRACED_FOREACH(int32_t, k, kInt32Values) {
+    TRACED_FOREACH(int32_t, l, kInt32Values) {
+      if (k == 0 || k == -1 || l == 0 || l == -1) continue;
+
+      // (x & K) & L => x & (K & L)
+      Reduction const r1 = Reduce(graph()->NewNode(
+          machine()->Word32And(),
+          graph()->NewNode(machine()->Word32And(), p0, Int32Constant(k)),
+          Int32Constant(l)));
+      ASSERT_TRUE(r1.Changed());
+      EXPECT_THAT(r1.replacement(), IsWord32And(p0, IsInt32Constant(k & l)));
+
+      // (K & x) & L => x & (K & L)
+      Reduction const r2 = Reduce(graph()->NewNode(
+          machine()->Word32And(),
+          graph()->NewNode(machine()->Word32And(), Int32Constant(k), p0),
+          Int32Constant(l)));
+      ASSERT_TRUE(r2.Changed());
+      EXPECT_THAT(r2.replacement(), IsWord32And(p0, IsInt32Constant(k & l)));
+    }
+  }
+}
+
+
+// -----------------------------------------------------------------------------
 // Word32Xor
 
 
 TEST_F(MachineOperatorReducerTest, Word32XorWithWord32XorAndMinusOne) {
   Node* const p0 = Parameter(0);
 
   // (x ^ -1) ^ -1 => x
   Reduction r1 = Reduce(graph()->NewNode(
       machine()->Word32Xor(),
       graph()->NewNode(machine()->Word32Xor(), p0, Int32Constant(-1)),
@@ skipping 614 matching lines @@
     Reduction r = Reduce(node);
     ASSERT_TRUE(r.Changed());
     EXPECT_THAT(r.replacement(),
                 IsStore(rep, base, index, value, effect, control));
   }
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8