From e113a571c9007100e16a348fd4eb4f84891a46b4 Mon Sep 17 00:00:00 2001
From: "cjhopman@chromium.org"
 <cjhopman@chromium.org@4ff67af0-8c30-449e-8e8b-ad334ec8d88c>
Date: Tue, 29 Jul 2014 00:20:58 +0000
Subject: [PATCH] Fix optional neon support

On Android, we detect neon support at runtime and switch implementations
based on that. This requires that some parts of skia are compiled with
-mfpu=neon.

To support this, the -mfpu flag is moved out of the 'compiler' config
and into its own config. A target can then remove this config and supply
its own -mfpu flag (without having to duplicate all the other stuff in
the 'compiler' config).

BUG=359249

Review URL: https://codereview.chromium.org/371853007

git-svn-id: http://src.chromium.org/svn/trunk/src/build@286038 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
---
 config/BUILDCONFIG.gn    | 1 +
 config/arm.gni           | 2 +-
 config/compiler/BUILD.gn | 9 ++++++++-
 3 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/config/BUILDCONFIG.gn b/config/BUILDCONFIG.gn
index 79a24cebc..b05247e92 100644
--- a/config/BUILDCONFIG.gn
+++ b/config/BUILDCONFIG.gn
@@ -310,6 +310,7 @@ _native_compiler_configs = [
   "//build/config:feature_flags",
 
   "//build/config/compiler:compiler",
+  "//build/config/compiler:compiler_arm_fpu",
   "//build/config/compiler:chromium_code",
   "//build/config/compiler:default_include_dirs",
   "//build/config/compiler:default_warnings",
diff --git a/config/arm.gni b/config/arm.gni
index d3ed3c605..65cb160a5 100644
--- a/config/arm.gni
+++ b/config/arm.gni
@@ -21,7 +21,7 @@ if (cpu_arch == "arm") {
 
   if (is_android) {
     arm_use_neon = false
-    arm_optionally_use_neon = false
+    arm_optionally_use_neon = true
   } else {
     arm_use_neon = true
     arm_optionally_use_neon = true
diff --git a/config/compiler/BUILD.gn b/config/compiler/BUILD.gn
index 456ab1958..09f8e6270 100644
--- a/config/compiler/BUILD.gn
+++ b/config/compiler/BUILD.gn
@@ -134,7 +134,6 @@ config("compiler") {
       if (!is_android_webview_build) {
         cflags += [
           "-march=$arm_arch",
-          "-mfpu=$arm_fpu",
           "-mfloat-abi=$arm_float_abi",
         ]
         if (arm_tune != "") {
@@ -314,6 +313,14 @@ config("compiler") {
   }
 }
 
+config("compiler_arm_fpu") {
+  if (cpu_arch == "arm" && !is_android_webview_build) {
+    cflags = [
+      "-mfpu=$arm_fpu",
+    ]
+  }
+}
+
 # runtime_library -------------------------------------------------------------
 #
 # Sets the runtime library and associated options.