For building v8 using gn on aix_ppc64, linux_s390x and linux_ppc64.

infra/mb/mb_config.pyl

Index: infra/mb/mb_config.pyl
diff --git a/infra/mb/mb_config.pyl b/infra/mb/mb_config.pyl
index 0df30d457129f96ad03ada3046d669349de1c0cb..ad6508eb3dd7f081af395a846d36140261ec2b85 100644
--- a/infra/mb/mb_config.pyl
+++ b/infra/mb/mb_config.pyl
@@ -65,6 +65,8 @@
       'V8 Linux64 - internal snapshot': 'gn_release_x64_internal',
       'V8 Linux64 - gyp': 'gyp_release_x64',
       'V8 Linux64 - verify csa': 'gn_release_x64_verify_csa',
+      # aix64
+      'V8 Aix64': 'gn_release_ppc64',

[Michael Achenbach, 2017/04/18 13:56:22]

Please do the mb_config.pyl change in a separate CL. After the gn support CL
lands, we can check for flag differences on the bots in:
https://build.chromium.org/p/client.v8.ports/builders/V8%20Linux%20-%20ppc64%...

You should also switch the beta/stable bots in the same CL and remove the
corresponding gyp config. The bots will first really switch when the CL
propagates to the branch.

       # Windows.
       'V8 Win32 - builder': 'gn_release_x86_minimal_symbols',
       'V8 Win32 - debug builder': 'gn_debug_x86_minimal_symbols',
@@ -280,6 +282,8 @@
       'gn', 'debug', 'x64', 'v8_enable_slow_dchecks'],
     'default_release_x64': [
       'gn', 'release', 'x64'],
+    'default_release_ppc64': [
+      'gn', 'release', 'ppc64'],
     'default_debug_x86': [
       'gn', 'debug', 'x86', 'v8_enable_slow_dchecks', 'v8_full_debug'],
     'default_optdebug_x86': [
@@ -370,6 +374,10 @@
       'gn', 'release_bot', 'x64', 'swarming', 'dcheck_always_on',
       'v8_enable_slow_dchecks', 'v8_verify_csa'],
 
+    # GN release configs for ppc64.
+    'gn_release_ppc64': [
+      'gn', 'release_bot', 'ppc64', 'swarming'],
+
     # GN debug configs for x64.
     'gn_debug_x64': [
       'gn', 'debug_bot', 'x64', 'swarming'],
@@ -600,6 +608,10 @@
                       'use_prebuilt_instrumented_libraries=1'),
     },
 
+    'ppc64': {
+       'gn_args': 'target_cpu="ppc64"',
+    },
+
     'release': {
       'gn_args': 'is_debug=false',
     },