Move .dwp files to lib.unstripped folder.

- .dwp files produced by clank build will now be output to
lib.unstripped folder instead of the root out folder. This is to ensure
they are in the expected place for Breakpad symbol generation and symbol
archiving.

Bug: 1112935
Change-Id: Id5cfb8a0188e3a6fa30fb56ed98bdb4e7da2af03
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2406595
Commit-Queue: Nelson Billing <nbilling@google.com>
Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#809448}

build/config/compiler/BUILD.gn

@@ -174,11 +174,6 @@ declare_args() {
                                                        current_cpu == "x64"))))
 }
 
-if (use_debug_fission == "default") {
-  use_debug_fission = is_debug && !is_android && !is_fuchsia && !is_apple &&
-                      !is_win && (use_gold || use_lld) && cc_wrapper == ""
-}
-
 if (is_win || is_android || (is_chromeos && is_chromeos_device)) {
   # Set the path to use orderfile for linking Chrome
   # Note that this is for using only one orderfile for linking
@@ -2350,10 +2345,7 @@ config("symbols") {
       # NOTE: This flag is for use by the link wrapper scripts. They are also
       # expected to remove it before sending the rest of ldflags to the actual
       # linker. Only expect Android Chrome build on Android OS to need this.
-      ldflags += [
-        "--generate-dwp",
-        "-gsplit-dwarf",
-      ]
+      ldflags += [ "-gsplit-dwarf" ]
     }
 
     # TODO(thakis): Figure out if there's a way to make this go for 32-bit,

build/config/compiler/compiler.gni

@@ -7,6 +7,7 @@ import("//build/config/chromecast_build.gni")
 import("//build/config/chromeos/args.gni")
 import("//build/config/compiler/pgo/pgo.gni")
 import("//build/config/sanitizers/sanitizers.gni")
+import("//build/toolchain/cc_wrapper.gni")
 import("//build/toolchain/goma.gni")
 import("//build/toolchain/toolchain.gni")
 import("//build_overrides/build.gni")
@@ -223,11 +224,19 @@ if (strip_absolute_paths_from_debug_symbols_default) {
   }
 }
 
+# If it wasn't manually set, then default use_debug_fission to false.
+assert(
+    use_debug_fission == "default" || use_debug_fission || !use_debug_fission,
+    "Invalid use_debug_fission.")
+if (use_debug_fission == "default") {
+  use_debug_fission = is_debug && !is_android && !is_fuchsia && !is_apple &&
+                      !is_win && (use_gold || use_lld) && cc_wrapper == ""
+}
+
 # If it wasn't manually set, set to an appropriate default.
 assert(symbol_level >= -1 && symbol_level <= 2, "Invalid symbol_level")
 if (symbol_level == -1) {
-  if (is_android && !is_component_build &&
-      !(use_debug_fission != "default" && use_debug_fission)) {
+  if (is_android && !is_component_build && !use_debug_fission) {
     # Reduce symbol level when it will cause invalid elf files to be created
     # (due to file size). https://crbug.com/648948.
     symbol_level = 1
@@ -277,8 +286,7 @@ if (forbid_non_component_debug_builds) {
 # toolchain there to build relatively small binaries.
 assert(
     ignore_elf32_limitations || !is_android || target_os == "chromeos" ||
-        is_component_build || symbol_level < 2 ||
-        (use_debug_fission != "default" && use_debug_fission),
+        is_component_build || symbol_level < 2 || use_debug_fission,
     "Android 32-bit non-component builds without DWARF Fission cannot " +
         "have symbol_level=2 due to 4GiB file size limit, see " +
         "https://crbug.com/648948. " + "If you really want to try this out, " +

build/extract_partition.py

@@ -50,7 +50,7 @@ def main():
   if args.dwp:
     dwp_args = [
         args.dwp, '-e', args.unstripped_output, '-o',
-        args.stripped_output + '.dwp'
+        args.unstripped_output + '.dwp'
     ]
     subprocess.check_call(dwp_args)
 

build/partitioned_shared_library.gni

@@ -103,11 +103,10 @@ template("partitioned_shared_library") {
       # Restrict to Android OS because ChromeOS uses the Android toolchain with
       # use_debug_fission set globally, which isn't reliable across all
       # possible build configs with Android.
-      if (is_android && target_os == "android" &&
-          use_debug_fission != "default" && use_debug_fission) {
+      if (is_android && target_os == "android" && use_debug_fission) {
         dwp = rebase_path("${android_tool_prefix}dwp", root_build_dir)
         args += [ "--dwp=${dwp}" ]
-        outputs += [ invoker.stripped_output + ".dwp" ]
+        outputs += [ invoker.unstripped_output + ".dwp" ]
       }
       args += [ rebase_path(sources[0], root_build_dir) ]
     }

build/toolchain/gcc_link_wrapper.py

@@ -54,10 +54,6 @@ def main():
                       help='Linking command')
   args = parser.parse_args()
 
-  generate_dwp = '--generate-dwp' in args.command
-  if generate_dwp:
-    args.command.remove('--generate-dwp')
-
   # Work-around for gold being slow-by-default. http://crbug.com/632230
   fast_env = dict(os.environ)
   fast_env['LC_ALL'] = 'C'
@@ -68,15 +64,13 @@ def main():
 
   # If dwp is set, then package debug info for this exe.
   dwp_proc = None
-  if generate_dwp:
-    if not args.dwp:
-      parser.error('--generate-dwp requireds --dwp')
+  if args.dwp:
     exe_file = args.output
     if args.unstripped_file:
       exe_file = args.unstripped_file
     dwp_proc = subprocess.Popen(
         wrapper_utils.CommandToRun(
-            [args.dwp, '-e', exe_file, '-o', args.output + '.dwp']))
+            [args.dwp, '-e', exe_file, '-o', exe_file + '.dwp']))
 
   # Finally, strip the linked executable (if desired).
   if args.strip:

build/toolchain/gcc_solink_wrapper.py

@@ -122,7 +122,6 @@ def main():
   # https://crbug.com/954311 tracks finding a better way to plumb these.
   link_only = InterceptFlag('--link-only', args.command)
   collect_inputs_only = InterceptFlag('--collect-inputs-only', args.command)
-  generate_dwp = InterceptFlag('--generate-dwp', args.command)
 
   # If only linking, we are likely generating a partitioned .so that will be
   # split apart later. In that case:
@@ -162,12 +161,10 @@ def main():
 
   # If dwp is set, then package debug info for this SO.
   dwp_proc = None
-  if generate_dwp:
-    if not args.dwp:
-      parser.error('--generate-dwp requireds --dwp')
+  if args.dwp:
     dwp_proc = subprocess.Popen(
         wrapper_utils.CommandToRun(
-            [args.dwp, '-e', args.sofile, '-o', args.output + '.dwp']))
+            [args.dwp, '-e', args.sofile, '-o', args.sofile + '.dwp']))
 
   # Next, generate the contents of the TOC file.
   result, toc = CollectTOC(args)

build/toolchain/gcc_toolchain.gni

@@ -417,7 +417,12 @@ template("gcc_toolchain") {
       # The host might not have a POSIX shell and utilities (e.g. Windows).
       solink_wrapper =
           rebase_path("//build/toolchain/gcc_solink_wrapper.py", root_build_dir)
-      command = "$python_path \"$solink_wrapper\" --readelf=\"$readelf\" --nm=\"$nm\" $strip_switch--dwp=\"${dwp}\" --sofile=\"$unstripped_sofile\" --tocfile=\"$tocfile\"$map_switch --output=\"$sofile\" -- $link_command"
+      dwp_switch = ""
+      if (is_android && target_os == "android" && use_debug_fission &&
+          symbol_level == 2) {
+        dwp_switch = " --dwp=\"${dwp}\""
+      }
+      command = "$python_path \"$solink_wrapper\" --readelf=\"$readelf\" --nm=\"$nm\" $strip_switch$dwp_switch --sofile=\"$unstripped_sofile\" --tocfile=\"$tocfile\"$map_switch --output=\"$sofile\" -- $link_command"
 
       if (target_cpu == "mipsel" && is_component_build && is_android) {
         rspfile_content = "-Wl,--start-group -Wl,--whole-archive {{inputs}} {{solibs}} -Wl,--no-whole-archive {{libs}} -Wl,--end-group"
@@ -454,6 +459,18 @@ template("gcc_toolchain") {
           runtime_outputs = [ unstripped_sofile ]
         }
       }
+
+      # Clank build will generate DWP files when Fission is used.
+      # Other builds generate DWP files outside of the gn link targets, if at
+      # all.
+      if (is_android && target_os == "android" && use_debug_fission &&
+          symbol_level == 2) {
+        outputs += [ unstripped_sofile + ".dwp" ]
+        if (defined(invoker.use_unstripped_as_runtime_outputs) &&
+            invoker.use_unstripped_as_runtime_outputs) {
+          runtime_outputs += [ unstripped_sofile + ".dwp" ]
+        }
+      }
       if (defined(map_file)) {
         outputs += [ map_file ]
       }
@@ -547,9 +564,17 @@ template("gcc_toolchain") {
         strip_switch = " --strip=\"${invoker.strip}\" --unstripped-file=\"$unstripped_outfile\""
       }
 
+      dwp_switch = ""
+      if (is_android && target_os == "android" && use_debug_fission &&
+          symbol_level == 2) {
+        dwp_switch = " --dwp=\"${dwp}\""
+      } else {
+        not_needed([ "dwp" ])
+      }
+
       link_wrapper =
           rebase_path("//build/toolchain/gcc_link_wrapper.py", root_build_dir)
-      command = "$python_path \"$link_wrapper\" --output=\"$outfile\"$strip_switch$map_switch --dwp=\"${dwp}\" -- $link_command"
+      command = "$python_path \"$link_wrapper\" --output=\"$outfile\"$strip_switch$map_switch$dwp_switch -- $link_command"
 
       description = "LINK $outfile"
       rspfile_content = "{{inputs}}"
@@ -561,6 +586,18 @@ template("gcc_toolchain") {
           runtime_outputs = [ unstripped_outfile ]
         }
       }
+
+      # Clank build will generate DWP files when Fission is used.
+      # Other builds generate DWP files outside of the gn link targets, if at
+      # all.
+      if (is_android && target_os == "android" && use_debug_fission &&
+          symbol_level == 2) {
+        outputs += [ unstripped_outfile + ".dwp" ]
+        if (defined(invoker.use_unstripped_as_runtime_outputs) &&
+            invoker.use_unstripped_as_runtime_outputs) {
+          runtime_outputs += [ unstripped_outfile + ".dwp" ]
+        }
+      }
       if (defined(invoker.link_outputs)) {
         outputs += invoker.link_outputs
       }
@@ -611,7 +648,6 @@ template("clang_toolchain") {
     readelf = "${toolprefix}readelf"
     ar = "${prefix}/llvm-ar"
     nm = "${toolprefix}nm"
-    dwp = "${toolprefix}dwp"
 
     forward_variables_from(invoker,
                            [