Add Syzygy support to Windows GN build.

chrome/tools/build/win/syzygy/BUILD.gn

Index: chrome/tools/build/win/syzygy/BUILD.gn
diff --git a/chrome/tools/build/win/syzygy/BUILD.gn b/chrome/tools/build/win/syzygy/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..14aa6fc7eb4d94e561c17a3af624f7fbd28c20b7
--- /dev/null
+++ b/chrome/tools/build/win/syzygy/BUILD.gn
@@ -0,0 +1,221 @@
+# Copyright 2015 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/chrome_build.gni")
+import("//build/config/sanitizers/sanitizers.gni")
+
+declare_args() {
+  # Generate Syzygy optimized binaries. Syzygy optimize mode is a profile
+  # guided optimization that reorders code for better locality.
+  syzygy_optimize =
+      is_win && is_official_build && !is_clang && symbol_level == 2
+}
+
+assert(!syzygy_optimize || !is_syzyasan,
+       "Don't do both syzygy_optimize and is_syzyasan")
+
+# Where the output binaries will be placed.
+syzygy_dest_dir = "$root_out_dir/syzygy"
+
+if (syzygy_optimize) {
+  # Generates a Syzygy optimize target.
+  #
+  #   dll_name (required)
+  #     Name of the DLL to be instrumented, with no extension or path. This
+  #     ${dll_name}.dll is assumed to be in the output directory and must be
+  #     generated by a dependency of this target.
+  #
+  #   deps (required)
+  #     Normal meaning.
+  template("syzygy_optimize") {
+    action(target_name) {
+      if (defined(invoker.visibility)) {
+        visibility = invoker.visibility
+      }
+      script = "//chrome/tools/build/win/syzygy/reorder.py"
+
+      dll_name = invoker.dll_name
+      input_dll = "$root_out_dir/$dll_name.dll"
+      input_pdb = "$root_out_dir/$dll_name.dll.pdb"
+
+      inputs = [
+        input_dll,
+        #input_pdb,
+      ]
+
+      outputs = [
+        "$syzygy_dest_dir/$dll_name.dll",
+        "$syzygy_dest_dir/$dll_name.dll.pdb",
+      ]
+
+      args = [
+        "--input_executable",
+        rebase_path(input_dll, root_build_dir),
+        "--input_symbol",
+        rebase_path(input_pdb, root_build_dir),
+        "--destination_dir",
+        rebase_path(syzygy_dest_dir, root_build_dir),
+      ]
+
+      if (defined(invoker.deps)) {
+        deps = invoker.deps
+      }
+    }
+  }
+
+  syzygy_optimize("chrome_dll_syzygy") {
+    dll_name = "chrome"
+    deps = [
+      "//chrome:main_dll",
+    ]
+  }
+  if (is_multi_dll_chrome) {
+    # Also instrument chrome_child.dll.
+    syzygy_optimize("chrome_child_dll_syzygy") {
+      dll_name = "chrome_child"
+      deps = [
+        "//chrome:chrome_child",
+      ]
+    }
+  }
+} else if (is_syzyasan) {
+  # Instruments a binary with SyzyAsan.
+  #
+  #   dll_name (required)
+  #     Name of the DLL to be instrumented, with no extension or path. This
+  #     ${dll_name}.dll is assumed to be in the output directory and must be
+  #     generated by a dependency of this target.
+  #
+  #   deps (required)
+  #     Normal meaning.
+  template("syzygy_asan") {
+    action(target_name) {
+      if (defined(invoker.visibility)) {
+        visibility = invoker.visibility
+      }
+      script = "//chrome/tools/build/win/syzygy/instrument.py"
+
+      filter = "syzyasan-instrumentation-filter.txt"
+      input_dll = "$root_out_dir/$dll_name.dll"
+      input_pdb = "$root_out_dir/$dll_name.dll.pdb"
+
+      inputs = [
+        filter,
+        input_dll,
+
+        #input_pdb,
+      ]
+
+      output_filter = "$syzygy_dest_dir/win-syzyasan-filter-$dll_name.txt.json"
+
+      outputs = [
+        "$syzygy_dest_dir/$dll_name.dll",
+        "$syzygy_dest_dir/$dll_name.dll.pdb",
+        output_filter,
+      ]
+
+      args = [
+        "--mode",
+        "asan",
+        "--input_executable",
+        rebase_path(input_dll, root_build_dir),
+        "--input_symbol",
+        rebase_path(input_pdb, root_build_dir),
+        "--filter",
+        rebase_path(filter, root_build_dir),
+        "--output-filter-file",
+        rebase_path(output_filter, root_build_dir),
+        "--destination_dir",
+        rebase_path(syzygy_dest_dir, root_build_dir),
+      ]
+
+      deps = [
+        "//chrome/tools/build/win/syzygy:copy_syzyasan_binaries",
+      ]
+      if (defined(invoker.deps)) {
+        deps += invoker.deps
+      }
+      if (defined(invoker.public_deps)) {
+        public_deps = invoker.public_deps
+      }
+    }
+  }
+
+  syzygy_asan("chrome_dll_syzygy") {
+    dll_name = "chrome"
+    deps = [
+      "//chrome:main_dll",
+    ]
+  }
+
+  if (is_multi_dll_chrome) {
+    # Also instrument chrome_child.dll.
+    #
+    # For official builds, the instrumented version will be put into an
+    # "instrumented" subdirectory and the regular output will be
+    # uninstrumented. Otherwise, chrome_child is also instrumented to the
+    # normal place.
+    syzygy_asan("chrome_child_dll_syzygy") {
+      dll_name = "chrome_child"
+      deps = [
+        "//chrome:chrome_child",
+      ]
+
+      if (is_official_build) {
+        dest_dir = "$syzygy_dest_dir/instrumented"
+        deps += [ ":chrome_child_dll_syzygy_copy" ]
+      } else {
+        dest_dir = syzygy_dest_dir
+      }
+    }
+
+    if (is_official_build) {
+      # Copies the uninstrumented chrome_child.dll.
+      # GYP version: chrome/chrome_syzygy.gyp:chrome_child_dll_syzygy_copy
+      copy("chrome_child_dll_syzygy_copy") {
+        sources = [
+          "$root_out_dir/chrome_child.dll",
+          "$root_out_dir/chrome_child.dll.pdb",
+        ]
+        outputs = [
+          "$syzygy_dest_dir/{{source_file_part}}",
+        ]
+        deps = [
+          "//chrome:chrome_child",
+        ]
+      }
+    }
+  }
+} else {
+  # No syzygy. Generate dummy targets so other targets can unconditionally
+  # depend on these without having to duplicate our conditions.
+  group("chrome_dll_syzygy") {
+  }
+  if (is_multi_dll_chrome) {
+    group("chrome_child_dll_syzygy") {
+    }
+  }
+}
+
+if (is_syzyasan || syzygy_optimize) {
+  copy("copy_syzyasan_binaries") {
+    visibility = [ "//chrome/*" ]
+
+    source_dir = "//third_party/syzygy/binaries/exe"
+
+    sources = [
+      "$source_dir/agent_logger.exe",
+      "$source_dir/minidump_symbolizer.py",
+      "$source_dir/syzyasan_rtl.dll",
+      "$source_dir/syzyasan_rtl.dll.pdb",
+    ]
+
+    outputs = [
+      "$syzygy_dest_dir/{{source_file_part}}",
+    ]
+  }
+}
+
+# Prevent unused variable warning for code paths where this is unused.
+assert(syzygy_dest_dir != "")