Bug 915648 - Parallelize make export. r=gps

Makefile.in

@@ -217,3 +217,10 @@ ifdef ENABLE_TESTS
 check::
 	$(call SUBMAKE,$@,js/src)
 endif
+
+ifdef MOZ_PSEUDO_DERECURSE
+# Interdependencies for parallel export.
+js/xpconnect/src/export: config/makefiles/precompile/export
+accessible/src/xpcom/export: config/makefiles/precompile/export
+js/src/export: mfbt/export
+endif

config/recurse.mk

@@ -22,7 +22,8 @@ endif
 #   make -C foo/baz
 #   make -C qux
 
-ifeq (1_.,$(MOZ_PSEUDO_DERECURSE)_$(DEPTH))
+# MOZ_PSEUDO_DERECURSE can have values other than 1.
+ifeq (1_.,$(if $(MOZ_PSEUDO_DERECURSE),1)_$(DEPTH))
 
 include root.mk
 
@@ -88,6 +89,12 @@ ifdef BUG_915535_FIXED
 	$(call BUILDSTATUS,TIERDIR_FINISH $(CURRENT_TIER) $(subtier_of_$(subst /,_,$*)) $*)
 endif
 
+# The export tier requires nsinstall, which is built from config. So every
+# subdirectory traversal needs to happen after traversing config.
+ifeq ($(CURRENT_TIER),export)
+$(addsuffix /$(CURRENT_TIER),$(filter-out config,$(CURRENT_DIRS))): config/$(CURRENT_TIER)
+endif
+
 else
 
 # Don't recurse if MAKELEVEL is NO_RECURSE_MAKELEVEL as defined above, but

js/src/config/recurse.mk

@@ -88,6 +88,12 @@ ifdef BUG_915535_FIXED
 	$(call BUILDSTATUS,TIERDIR_FINISH $(CURRENT_TIER) $(subtier_of_$(subst /,_,$*)) $*)
 endif
 
+# The export tier requires nsinstall, which is built from config. So every
+# subdirectory traversal needs to happen after traversing config.
+ifeq ($(CURRENT_TIER),export)
+$(addsuffix /$(CURRENT_TIER),$(filter-out config,$(CURRENT_DIRS))): config/$(CURRENT_TIER)
+endif
+
 else
 
 # Don't recurse if MAKELEVEL is NO_RECURSE_MAKELEVEL as defined above, but

moz.build

@@ -1,3 +1,4 @@
+DEFINES['FOO'] = '1'
 # -*- Mode: python; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 40 -*-
 # vim: set filetype=python:
 # This Source Code Form is subject to the terms of the Mozilla Public

python/mozbuild/mozbuild/backend/recursivemake.py

@@ -294,6 +294,11 @@ class RecursiveMakeBackend(CommonBackend):
 
         self._traversal = RecursiveMakeTraversal()
 
+        derecurse = self.environment.substs.get('MOZ_PSEUDO_DERECURSE', '').split(',')
+        self._parallel_export = False
+        if derecurse != [''] and not 'no-parallel-export' in derecurse:
+            self._parallel_export = True
+
     def _update_from_avoid_write(self, result):
         existed, updated = result
 
@@ -390,15 +395,8 @@ class RecursiveMakeBackend(CommonBackend):
         convenience variables, and the other dependency definitions for a
         hopefully proper directory traversal.
         """
-        # Skip static dirs during export traversal
-        def export_filter(current, subdirs):
-            return current, subdirs.parallel, \
-                subdirs.dirs + subdirs.tests + subdirs.tools
-
-        # compile and tools build everything in parallel, but skip precompile.
-        def other_filter(current, subdirs):
-            if current == 'subtiers/precompile':
-                return None, [], []
+        # Traverse directories in parallel, and skip static dirs
+        def parallel_filter(current, subdirs):
             all_subdirs = subdirs.parallel + subdirs.dirs + \
                           subdirs.tests + subdirs.tools
             # subtiers/*_start and subtiers/*_finish, under subtiers/*, are
@@ -408,6 +406,20 @@ class RecursiveMakeBackend(CommonBackend):
                 return current, [], all_subdirs
             return current, all_subdirs, []
 
+        # Skip static dirs during export traversal, or build everything in
+        # parallel when enabled.
+        def export_filter(current, subdirs):
+            if self._parallel_export:
+                return parallel_filter(current, subdirs)
+            return current, subdirs.parallel, \
+                subdirs.dirs + subdirs.tests + subdirs.tools
+
+        # compile and tools build everything in parallel, but skip precompile.
+        def other_filter(current, subdirs):
+            if current == 'subtiers/precompile':
+                return None, [], []
+            return parallel_filter(current, subdirs)
+
         # Skip tools dirs during libs traversal
         def libs_filter(current, subdirs):
             if current == 'subtiers/precompile':