[turbofan] Distinguish between change- and truncate-tagged-to-float64.

src/compiler/verifier.cc

Index: src/compiler/verifier.cc
diff --git a/src/compiler/verifier.cc b/src/compiler/verifier.cc
index 0d3f69fcf58cc6121c985c420045732af2eaa5bc..5652a96912bab83965d20e5475eed395ccb54734 100644
--- a/src/compiler/verifier.cc
+++ b/src/compiler/verifier.cc
@@ -822,6 +822,16 @@ void Verifier::Visitor::Check(Node* node) {
       // CheckUpperIs(node, to));
       break;
     }
+    case IrOpcode::kTruncateTaggedToFloat64: {
+      // NumberOrUndefined /\ Tagged -> Number /\ UntaggedFloat64
+      // TODO(neis): Activate once ChangeRepresentation works in typer.
+      // Type* from = Type::Intersect(Type::NumberOrUndefined(),
+      // Type::Tagged());
+      // Type* to = Type::Intersect(Type::Number(), Type::UntaggedFloat64());
+      // CheckValueInputIs(node, 0, from));
+      // CheckUpperIs(node, to));
+      break;
+    }
     case IrOpcode::kChangeInt31ToTaggedSigned: {
       // Signed31 /\ UntaggedInt32 -> Signed31 /\ Tagged
       // TODO(neis): Activate once ChangeRepresentation works in typer.