[simd] Disable Simd Scalar lowering for x64, enable tests for all other architectures.

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 <memory>
 
 #include "src/isolate-inl.h"
 
@@ skipping 3330 matching lines @@
       os << "Compilation failed: " << graph_construction_result_ << std::endl;
     }
     return nullptr;
   }
 
   if (machine->Is32()) {
     Int64Lowering r(graph, machine, common, jsgraph_->zone(), function_->sig);
     r.LowerGraph();
   }
 
-  SimdScalarLowering(graph, machine, common, jsgraph_->zone(), function_->sig)
-      .LowerGraph();
+  if (!CpuFeatures::SupportsSimd128()) {
+    SimdScalarLowering(graph, machine, common, jsgraph_->zone(), function_->sig)
+        .LowerGraph();
+  }
 
   int index = static_cast<int>(function_->func_index);
 
   if (index >= FLAG_trace_wasm_ast_start && index < FLAG_trace_wasm_ast_end) {
     OFStream os(stdout);
     PrintAst(isolate_->allocator(), body, os, nullptr);
   }
   if (FLAG_trace_wasm_decode_time) {
     *decode_ms = decode_timer.Elapsed().InMillisecondsF();
   }
@@ skipping 126 matching lines @@
                             function_->code_start_offset),
            compile_ms);
   }
 
   return code;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8