GN: aix port along with linux_s390x, linux_ppc64 and linux_ppc64le support.

tools/gn/bootstrap/bootstrap.py

Index: tools/gn/bootstrap/bootstrap.py
diff --git a/tools/gn/bootstrap/bootstrap.py b/tools/gn/bootstrap/bootstrap.py
index 937427c6b4ce98e0d3d11bf26bfbc7864517e6da..8a16147ee7c2235a716fa555f3de7879c34d3191 100755
--- a/tools/gn/bootstrap/bootstrap.py
+++ b/tools/gn/bootstrap/bootstrap.py
@@ -32,7 +32,8 @@ SRC_ROOT = os.path.dirname(os.path.dirname(GN_ROOT))
 is_win = sys.platform.startswith('win')
 is_linux = sys.platform.startswith('linux')
 is_mac = sys.platform.startswith('darwin')
-is_posix = is_linux or is_mac
+is_aix = sys.platform.startswith('aix')
+is_posix = is_linux or is_mac or is_aix
 
 def check_call(cmd, **kwargs):
   logging.debug('Running: %s', ' '.join(cmd))
@@ -222,6 +223,8 @@ def write_generic_ninja(path, static_libraries, executables,
     template_filename = 'build_vs.ninja.template'
   elif is_mac:
     template_filename = 'build_mac.ninja.template'
+  elif is_aix:
+    template_filename = 'build_aix.ninja.template'
   else:
     template_filename = 'build.ninja.template'
 
@@ -297,6 +300,11 @@ def write_gn_ninja(path, root_gen_dir, options):
     cxx = os.environ.get('CXX', 'cl.exe')
     ld = os.environ.get('LD', 'link.exe')
     ar = os.environ.get('AR', 'lib.exe')
+  elif is_aix:
+    cc = os.environ.get('CC', 'gcc')
+    cxx = os.environ.get('CXX', 'c++')
+    ld = os.environ.get('LD', cxx)
+    ar = os.environ.get('AR', 'ar -X64')
   else:
     cc = os.environ.get('CC', 'cc')
     cxx = os.environ.get('CXX', 'c++')
@@ -317,6 +325,8 @@ def write_gn_ninja(path, root_gen_dir, options):
     if options.debug:
       cflags.extend(['-O0', '-g'])
     else:
+      # The linux::ppc64 BE binary doesn't "work" when
+      # optimization level is set to 2 (0 works fine).

[Dirk Pranke, 2017/04/14 01:19:33]

This comment confuses me. If this is true, doesn't this mean that there should
be a check for ppc64 BE here somewhere?

[rayb, 2017/04/19 19:51:50]

The current bootstrap script has no way of detecting host architecture. We could
add that logic (not sure if it's worth). This wouldn't be an issue once we start
building GN with a GN binary on the aforementioned platforms(because then this
can be just handled inside build/config/toolchain/). Where we would just be
using the debug binary on ppc64 BE for the first iteration and after that
everything else should be straight forward (once we make the required changes to
build/).
And while we are on that topic, I think the changes required for building GN
using a GN binary should probably go on a separate cl(once these changes go
through).
Also I should probably elaborate a little what I meant by "does not work" for
ppc64 BE. With optimization level at anything greater than 0, we still get a GN
binary. But when running it to build something like v8, the generated .ninja
files would have entries where the right hand side of the assignment would be
missing (of course ninja fails when it comes to using those .ninja files to
build v8). 
So for example 'defines' would look something like "defines = " instead of
"defines = -DV8_DEPRECATION_WARNINGS ..". But things such as 'label_name' or the
required source file entries would come out just fine. Note that that once
optimization level is set to '0', it works completely fine. From my
understanding both the builds follow the exact same code path. 

       cflags.extend(['-O2', '-g0'])
 
     cflags.extend([
@@ -327,6 +337,9 @@ def write_gn_ninja(path, root_gen_dir, options):
         '-fno-exceptions'
     ])
     cflags_cc.extend(['-std=c++11', '-Wno-c++11-narrowing'])
+    if is_aix:
+     cflags.extend(['-maix64'])
+     ldflags.extend([ '-maix64 -Wl,-bbigtoc' ])
   elif is_win:
     if not options.debug:
       cflags.extend(['/Ox', '/DNDEBUG', '/GL'])
@@ -596,8 +609,7 @@ def write_gn_ninja(path, root_gen_dir, options):
         'cflags': cflags + ['-DHAVE_CONFIG_H'],
     }
 
-  if is_linux:
-    libs.extend(['-lrt', '-latomic'])
+  if is_linux or is_aix:
     ldflags.extend(['-pthread'])
 
     static_libraries['xdg_user_dirs'] = {
@@ -624,13 +636,25 @@ def write_gn_ninja(path, root_gen_dir, options):
         'base/threading/platform_thread_linux.cc',
         'base/trace_event/malloc_dump_provider.cc',
     ])
-    static_libraries['libevent']['include_dirs'].extend([
-        os.path.join(SRC_ROOT, 'base', 'third_party', 'libevent', 'linux')
-    ])
-    static_libraries['libevent']['sources'].extend([
-        'base/third_party/libevent/epoll.c',
-    ])
-
+    if is_linux:
+      libs.extend(['-lrt', '-latomic'])
+      static_libraries['libevent']['include_dirs'].extend([
+          os.path.join(SRC_ROOT, 'base', 'third_party', 'libevent', 'linux')
+      ])
+      static_libraries['libevent']['sources'].extend([
+         'base/third_party/libevent/epoll.c',
+      ])
+    else:
+      libs.extend(['-lrt'])
+      static_libraries['base']['sources'].extend([
+          'base/process/internal_aix.cc'
+      ])
+      static_libraries['libevent']['include_dirs'].extend([
+          os.path.join(SRC_ROOT, 'base', 'third_party', 'libevent', 'aix')
+      ])
+      static_libraries['libevent']['include_dirs'].extend([
+          os.path.join(SRC_ROOT, 'base', 'third_party', 'libevent', 'compat')
+      ])
 
   if is_mac:
     static_libraries['base']['sources'].extend([