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

test/cctest/BUILD.gn

 # Copyright 2016 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.
 
 import("../../gni/v8.gni")
 
 v8_executable("cctest") {
   testonly = true
 
   sources = [
@@ skipping 172 matching lines @@
     "trace-extension.cc",
     "trace-extension.h",
     "types-fuzz.h",
     "wasm/test-managed.cc",
     "wasm/test-run-wasm-64.cc",
     "wasm/test-run-wasm-asmjs.cc",
     "wasm/test-run-wasm-interpreter.cc",
     "wasm/test-run-wasm-js.cc",
     "wasm/test-run-wasm-module.cc",
     "wasm/test-run-wasm-relocation.cc",
+    "wasm/test-run-wasm-simd-lowering.cc",
     "wasm/test-run-wasm.cc",
     "wasm/test-wasm-stack.cc",
     "wasm/test-wasm-trap-position.cc",
     "wasm/wasm-run-utils.h",
   ]
 
   if (v8_current_cpu == "arm") {
     sources += [  ### gcmole(arch:arm) ###
       "test-assembler-arm.cc",
       "test-code-stubs-arm.cc",
@@ skipping 67 matching lines @@
   } else if (v8_current_cpu == "x64") {
     sources += [  ### gcmole(arch:x64) ###
       "test-assembler-x64.cc",
       "test-code-stubs-x64.cc",
       "test-code-stubs.cc",
       "test-code-stubs.h",
       "test-disasm-x64.cc",
       "test-log-stack-tracer.cc",
       "test-macro-assembler-x64.cc",
       "test-run-wasm-relocation-x64.cc",
-      "wasm/test-run-wasm-simd-lowering.cc",
       "wasm/test-run-wasm-simd.cc",
     ]

[bbudge, 2016/11/18 19:30:59]

You can remove the lowering tests from sources here, i.e.
sources -= [
  "wasm/test-run-wasm-simd-lowering.cc"
]

Then you don't have to comment out the tests for archs that support SIMD without
lowering.

Alternatively we could only add this file to sources for platforms that don't
support SIMD, which is all of them except x64 right now. That might be the
clearest, although it's more verbose.

[gdeepti, 2016/11/21 19:30:02]

I was not sure which way was cleaner as most architectures currently do not
support SIMD, and this particular test file had no architecture specific
functionality. Fixed to add to sources only for platforms that do not support
SIMD. 

   } else if (v8_current_cpu == "x87") {
     sources += [  ### gcmole(arch:x87) ###
       "test-assembler-x87.cc",
       "test-code-stubs-x87.cc",
       "test-code-stubs.cc",
       "test-code-stubs.h",
       "test-disasm-x87.cc",
       "test-log-stack-tracer.cc",
       "test-macro-assembler-x87.cc",
       "test-run-wasm-relocation-x87.cc",
@@ skipping 121 matching lines @@
   ]
 
   deps = [
     "../..:v8",
     "../..:v8_libbase",
     "../..:v8_libplatform",
     "//build/config/sanitizers:deps",
     "//build/win:default_exe_manifest",
   ]
 }