[wasm] Int64Lowering of F64ReinterpretI64.

test/unittests/compiler/int64-lowering-unittest.cc

 // Copyright 2016 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/compiler/int64-lowering.h"
 #include "src/compiler/common-operator.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/machine-operator.h"
 #include "src/compiler/node.h"
 
@@ skipping 473 matching lines @@
       graph()->NewNode(machine()->ChangeUint32ToUint64(),
                        graph()->NewNode(machine()->TruncateInt64ToInt32(),
                                         Int64Constant(value(0)))),
       MachineRepresentation::kWord64);
 
   EXPECT_THAT(graph()->end()->InputAt(1),
               IsReturn2(IsInt32Constant(low_word_value(0)), IsInt32Constant(0),
                         start(), start()));
 }
 // kExprF64ReinterpretI64:
+TEST_F(Int64LoweringTest, F64ReinterpretI64) {
+  LowerGraph(graph()->NewNode(machine()->BitcastInt64ToFloat64(),
+                              Int64Constant(value(0))),
+             MachineRepresentation::kFloat64);
+
+  Capture<Node*> stack_slot_capture;
+  Matcher<Node*> stack_slot_matcher =
+      IsStackSlot(MachineRepresentation::kWord64);
+
+  Capture<Node*> store_capture;
+  Matcher<Node*> store_matcher =
+      IsStore(StoreRepresentation(MachineRepresentation::kWord32,
+                                  WriteBarrierKind::kNoWriteBarrier),
+              AllOf(CaptureEq(&stack_slot_capture), stack_slot_matcher),
+              IsInt32Constant(0), IsInt32Constant(low_word_value(0)),
+              IsStore(StoreRepresentation(MachineRepresentation::kWord32,
+                                          WriteBarrierKind::kNoWriteBarrier),
+                      AllOf(CaptureEq(&stack_slot_capture), stack_slot_matcher),
+                      IsInt32Constant(4), IsInt32Constant(high_word_value(0)),
+                      start(), start()),
+              start());
+
+  EXPECT_THAT(
+      graph()->end()->InputAt(1),
+      IsReturn(IsLoad(MachineType::Float64(),
+                      AllOf(CaptureEq(&stack_slot_capture), stack_slot_matcher),
+                      IsInt32Constant(0),
+                      AllOf(CaptureEq(&store_capture), store_matcher), start()),
+               start(), start()));
+}
 // kExprI64ReinterpretF64:
 TEST_F(Int64LoweringTest, I64ReinterpretF64) {
   LowerGraph(graph()->NewNode(machine()->BitcastFloat64ToInt64(),
                               Float64Constant(bit_cast<double>(value(0)))),
              MachineRepresentation::kWord64);
 
   Capture<Node*> stack_slot;
   Matcher<Node*> stack_slot_matcher =
       IsStackSlot(MachineRepresentation::kWord64);
 
@@ skipping 45 matching lines @@
 
   EXPECT_THAT(
       graph()->end()->InputAt(1),
       IsReturn2(IsInt32Add(IsWord32Popcnt(IsInt32Constant(low_word_value(0))),
                            IsWord32Popcnt(IsInt32Constant(high_word_value(0)))),
                 IsInt32Constant(0), start(), start()));
 }
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8