GYP+GN plumbing for SSE4.2, AVX, and AVX2 in Skia.

skia/BUILD.gn

Index: skia/BUILD.gn
diff --git a/skia/BUILD.gn b/skia/BUILD.gn
index f3fd404da5bfce94e9fb783a2df8752ce54bb28d..e6fc643357486c02e44413308d1b6b7c80248eb0 100644
--- a/skia/BUILD.gn
+++ b/skia/BUILD.gn
@@ -520,7 +520,7 @@ if (current_cpu == "x86" || current_cpu == "x64") {
       "//build/config/compiler:no_chromium_code",
     ]
   }
-  source_set("skia_opts_sse4") {
+  source_set("skia_opts_sse41") {
     sources = gypi_skia_opts.sse41_sources
     if (!is_win || is_clang) {
       cflags = [ "-msse4.1" ]
@@ -536,6 +536,54 @@ if (current_cpu == "x86" || current_cpu == "x64") {
       "//build/config/compiler:no_chromium_code",
     ]
   }
+  source_set("skia_opts_sse42") {
+    sources = gypi_skia_opts.sse42_sources
+    if (!is_win || is_clang) {
+      cflags = [ "-msse4.2" ]
+    }
+    if (is_win) {
+      defines = [ "SK_CPU_SSE_LEVEL=42" ]
+    }
+    visibility = [ ":skia_opts" ]
+    configs -= [ "//build/config/compiler:chromium_code" ]
+    configs += [
+      ":skia_config",
+      ":skia_library_config",
+      "//build/config/compiler:no_chromium_code",
+    ]
+  }
+  source_set("skia_opts_avx") {
+    sources = gypi_skia_opts.avx_sources
+    if (!is_win || is_clang) {
+      cflags = [ "-mavx" ]
+    }
+    if (is_win) {
+      cflags = [ "/arch:AVX" ]
+    }
+    visibility = [ ":skia_opts" ]
+    configs -= [ "//build/config/compiler:chromium_code" ]
+    configs += [
+      ":skia_config",
+      ":skia_library_config",
+      "//build/config/compiler:no_chromium_code",
+    ]
+  }
+  source_set("skia_opts_avx2") {
+    sources = gypi_skia_opts.avx2_sources
+    if (!is_win || is_clang) {
+      cflags = [ "-mavx2" ]
+    }
+    if (is_win) {
+      cflags = [ "/arch:AVX2" ]
+    }
+    visibility = [ ":skia_opts" ]
+    configs -= [ "//build/config/compiler:chromium_code" ]
+    configs += [
+      ":skia_config",
+      ":skia_library_config",
+      "//build/config/compiler:no_chromium_code",
+    ]
+  }
 }
 source_set("skia_opts") {
   cflags = []
@@ -549,7 +597,10 @@ source_set("skia_opts") {
     sources = gypi_skia_opts.sse2_sources
     deps += [
       ":skia_opts_sse3",
-      ":skia_opts_sse4",
+      ":skia_opts_sse41",
+      ":skia_opts_sse42",
+      ":skia_opts_avx",
+      ":skia_opts_avx2",
     ]
   } else if (current_cpu == "arm") {
     # The assembly uses the frame pointer register (r7 in Thumb/r11 in