[wasm] Int64Lowering of I64XConvertI32.

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 338 matching lines @@
                       machine()->Uint32LessThan());
       break;
     }
     case IrOpcode::kUint64LessThanOrEqual: {
       LowerComparison(node, machine()->Uint32LessThan(),
                       machine()->Uint32LessThanOrEqual());
       break;
     }
 
     // kExprI64SConvertI32:
-    // kExprI64UConvertI32:
-
+    case IrOpcode::kChangeInt32ToInt64: {
+      DCHECK(node->InputCount() == 1);
+      Node* input = node->InputAt(0);
+      if (HasReplacementLow(input)) {
+        input = GetReplacementLow(input);
+      }
+      // We use SAR to preserve the sign in the high word.
+      ReplaceNode(
+          node, input,
+          graph()->NewNode(machine()->Word32Sar(), input,
+                           graph()->NewNode(common()->Int32Constant(31))));
+      node->NullAllInputs();
+      break;
+    }
+    // kExprI64UConvertI32: {
+    case IrOpcode::kChangeUint32ToUint64: {
+      DCHECK(node->InputCount() == 1);
+      Node* input = node->InputAt(0);
+      if (HasReplacementLow(input)) {
+        input = GetReplacementLow(input);
+      }
+      ReplaceNode(node, input, graph()->NewNode(common()->Int32Constant(0)));
+      node->NullAllInputs();
+      break;
+    }
     // kExprF64ReinterpretI64:
     // kExprI64ReinterpretF64:
 
     // kExprI64Clz:
     // kExprI64Ctz:
     // kExprI64Popcnt:
 
     default: { DefaultLowering(node); }
   }
 }
@@ skipping 55 matching lines @@
 }
 
 Node* Int64Lowering::GetReplacementHigh(Node* node) {
   Node* result = replacements_[node->id()].high;
   DCHECK(result);
   return result;
 }
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8