[wasm] Int64Lowering of Word64Popcnt.

src/compiler/int64-lowering.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/compiler/int64-lowering.h"
 #include "src/compiler/common-operator.h"
 #include "src/compiler/graph.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/machine-operator.h"
 #include "src/compiler/node-properties.h"
@@ skipping 431 matching lines @@
       }
       ReplaceNode(node, input, graph()->NewNode(common()->Int32Constant(0)));
       node->NullAllInputs();
       break;
     }
     // kExprF64ReinterpretI64:
     // kExprI64ReinterpretF64:
 
     // kExprI64Clz:
     // kExprI64Ctz:
+    case IrOpcode::kWord64Popcnt: {
+      DCHECK(node->InputCount() == 1);
+      Node* input = node->InputAt(0);
+      // We assume that a Word64Popcnt node only has been created if
+      // Word32Popcnt is actually supported.
+      DCHECK(machine()->Word32Popcnt().IsSupported());
+      ReplaceNode(node, graph()->NewNode(
+                            machine()->Int32Add(),
+                            graph()->NewNode(machine()->Word32Popcnt().op(),
+                                             GetReplacementLow(input)),
+                            graph()->NewNode(machine()->Word32Popcnt().op(),
+                                             GetReplacementHigh(input))),
+                  graph()->NewNode(common()->Int32Constant(0)));
+      break;
+    }
     // kExprI64Popcnt:
 
     default: { DefaultLowering(node); }
   }
 }
 
 void Int64Lowering::LowerComparison(Node* node, const Operator* high_word_op,
                                     const Operator* low_word_op) {
   DCHECK(node->InputCount() == 2);
   Node* left = node->InputAt(0);
@@ skipping 50 matching lines @@
 }
 
 Node* Int64Lowering::GetReplacementHigh(Node* node) {
   Node* result = replacements_[node->id()].high;
   DCHECK(result);
   return result;
 }
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8