[MIPS] Support for MIPS PNaCl in PPAPI

ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_irt_shim.gyp

 # Copyright (c) 2012 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.
 
 {
   'includes': [
     '../../../../../native_client/build/untrusted.gypi',
   ],
   'targets': [
     {
       'target_name': 'pnacl_irt_shim',
       'type': 'none',
       'variables': {
         'nlib_target': 'libpnacl_irt_shim.a',
         'out_newlib_arm': '>(tc_lib_dir_pnacl_translate)/lib-arm/libpnacl_irt_shim.a',
         'out_newlib32': '>(tc_lib_dir_pnacl_translate)/lib-x86-32/libpnacl_irt_shim.a',
         'out_newlib64': '>(tc_lib_dir_pnacl_translate)/lib-x86-64/libpnacl_irt_shim.a',
+        'out_newlib_mips': '>(tc_lib_dir_pnacl_translate)/lib-mips/libpnacl_irt_shim.a',

[jvoung (off chromium), 2014/02/06 00:39:56]

lib-mips32 to be consistent w/ the other part? Doesn't matter much I guess...

[petarj, 2014/02/20 00:23:18]

This line is removed now.

         'build_glibc': 0,
         'build_newlib': 1,
         'force_arm_pnacl': 1,
         'sources': [
           'pnacl_shim.c',
           'shim_entry.c',
           'shim_ppapi.c',
         ],
         'include_dirs': [
           '../../../..',
         ],
         'extra_args': [
           '--strip-debug',
         ],
         'conditions': [
           ['target_arch=="arm"', {
             'compile_flags': [
               '--pnacl-allow-translate',
               '--pnacl-allow-native',
               '-arch', 'arm',
             ],
           }],
+          ['target_arch=="mipsel"', {
+            'compile_flags': [
+              '--pnacl-allow-translate',

[jvoung (off chromium), 2014/02/06 00:39:56]

Currently have a CL to change this a bit. CC'ed you on part one of it.

What is the native ABI for the IRT? Is it based on clang's le32-none-nacl? Are
you also using the pnacl ABI stabilization passes like ExpandByVal when you
build the IRT?

If so, this shim might be a nop and you can use a dummy shim or change the
linker rules to skip the shim.

[petarj, 2014/02/20 00:23:18]

It's le32-unknown-nacl.
Yes, '-expand-byval' is used.
 
You are right. We have just modified the code to use dummy shim.

+              '--pnacl-allow-native',
+              '-arch', 'mips',
+            ],
+          }],
         ],
       },
       'dependencies': [
         '<(DEPTH)/native_client/tools.gyp:prep_toolchain',
       ],
     },
   ],
 }