[turbofan] Introduce new operators Float32SubPreserveNan and Float64SubPreserveNan for wasm.

src/compiler/typer.cc

Index: src/compiler/typer.cc
diff --git a/src/compiler/typer.cc b/src/compiler/typer.cc
index 4349eeab378d41fee88a014d986870aab4d30e8d..0a96dc743409cadd1e7f80522ee6f7bbed7e1ec9 100644
--- a/src/compiler/typer.cc
+++ b/src/compiler/typer.cc
@@ -2343,6 +2343,9 @@ Type* Typer::Visitor::TypeFloat32Add(Node* node) { return Type::Number(); }
 
 Type* Typer::Visitor::TypeFloat32Sub(Node* node) { return Type::Number(); }
 
+Type* Typer::Visitor::TypeFloat32SubPreserveNan(Node* node) {
+  return Type::Number();
+}
 
 Type* Typer::Visitor::TypeFloat32Mul(Node* node) { return Type::Number(); }
 
@@ -2383,6 +2386,9 @@ Type* Typer::Visitor::TypeFloat64Add(Node* node) { return Type::Number(); }
 
 Type* Typer::Visitor::TypeFloat64Sub(Node* node) { return Type::Number(); }
 
+Type* Typer::Visitor::TypeFloat64SubPreserveNan(Node* node) {
+  return Type::Number();
+}
 
 Type* Typer::Visitor::TypeFloat64Mul(Node* node) { return Type::Number(); }