GN: Fix skia build on mac, use -msse4.1 everywhere

skia/BUILD.gn

 # Copyright (c) 2013 The Chromium 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("//build/config/features.gni")
 import("//build/config/ui.gni")
 if (cpu_arch == "arm") {
   import("//build/config/arm.gni")
 }
 
@@ skipping 118 matching lines @@
   if (is_posix) {
     defines += [ "SK_USE_POSIX_THREADS" ]
   }
 
   if (is_android) {
     defines += [
       "SK_BUILD_FOR_ANDROID",
       "USE_CHROMIUM_SKIA",
     ]
   }
+
+  if (is_mac) {
+    defines += [ "SK_BUILD_FOR_MAC" ]
+  }
 }
 
 # Internal-facing config for Skia library code.
 config("skia_library_config") {
   # These include directories are only included for Skia code and are not
   # exported to dependents. It's not clear if this is on purpose, but this
   # matches the GYP build.
   include_dirs = []
   if (is_mac || is_ios) {
     include_dirs += [ "//third_party/skia/include/utils/mac" ]
@@ skipping 403 matching lines @@
       "//third_party/skia/include/core/SkTypes.h",
     ]
 
     # SSE 4
     if (cpu_arch == "x86") {
       sources += [ "//third_party/skia/src/opts/SkBlitRow_opts_SSE4_asm.S" ]
     } else {  # x64
       sources += [ "//third_party/skia/src/opts/SkBlitRow_opts_SSE4_x64_asm.S" ]
     }
 
-    if (is_linux || is_mac) {
+    if (is_linux) {
       cflags += [ "-msse4" ]
+    } else if (is_mac) {
+      cflags += [ "-msse4.1" ]

[Nico, 2014/07/08 17:20:52]

Is this actually needed? This currently uses msse4.1 in gyp probably because
there's GCC_ENABLE_SSE41_EXTENSIONS but no GCC_ENABLE_SSE4_EXTENSIONS in Xcode
(maybe there's no chip that supports sse4 but no sse4.1 in apple computers?) In
gyp, it makes sense to keep this separate, but in gn it might not.

     }
   } else if (cpu_arch == "arm") {
     sources = [
       "//third_party/skia/src/opts/SkBitmapProcState_opts_arm.cpp",
     ]
 
     # The assembly uses the frame pointer register (r7 in Thumb/r11 in
     # ARM), the compiler doesn't like that.
     cflags += [ "-fomit-frame-pointer" ]
 
@@ skipping 85 matching lines @@
     ":skia_config",
     "//build/config/compiler:no_chromium_code"
   ]
 
   deps = [
     "//base",
   ]
 
   visibility = ":skia"
 }