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

src/compiler/wasm-compiler.cc

 // Copyright 2015 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/wasm-compiler.h"
 
 #include "src/isolate-inl.h"
 
 #include "src/base/platform/elapsed-timer.h"
 #include "src/base/platform/platform.h"
@@ skipping 517 matching lines @@
     case wasm::kExprI64Rol:
       return BuildI64Rol(left, right);
     case wasm::kExprF32CopySign:
       return BuildF32CopySign(left, right);
     case wasm::kExprF64CopySign:
       return BuildF64CopySign(left, right);
     case wasm::kExprF32Add:
       op = m->Float32Add();
       break;
     case wasm::kExprF32Sub:
-      op = m->Float32Sub();
+      op = m->Float32SubPreserveNan();
       break;
     case wasm::kExprF32Mul:
       op = m->Float32Mul();
       break;
     case wasm::kExprF32Div:
       op = m->Float32Div();
       break;
     case wasm::kExprF32Eq:
       op = m->Float32Equal();
       break;
@@ skipping 10 matching lines @@
       op = m->Float32LessThan();
       std::swap(left, right);
       break;
     case wasm::kExprF32Le:
       op = m->Float32LessThanOrEqual();
       break;
     case wasm::kExprF64Add:
       op = m->Float64Add();
       break;
     case wasm::kExprF64Sub:
-      op = m->Float64Sub();
+      op = m->Float64SubPreserveNan();
       break;
     case wasm::kExprF64Mul:
       op = m->Float64Mul();
       break;
     case wasm::kExprF64Div:
       op = m->Float64Div();
       break;
     case wasm::kExprF64Eq:
       op = m->Float64Equal();
       break;
@@ skipping 2512 matching lines @@
                                  const wasm::WasmFunction* function) {
   WasmCompilationUnit* unit =
       CreateWasmCompilationUnit(thrower, isolate, module_env, function, 0);
   ExecuteCompilation(unit);
   return FinishCompilation(unit);
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8