Split the PNaCl IRT shim into 3 pieces, and include one piece into IRT.

(*) A "for irt" library, that will get linked into the IRT.
That library just has the auto-generated pnacl_shim.c file.
Also modify ppapi_proxy to include a "irt_shim_ppapi.c",
which makes use of the pnacl_shim.c file to define a private
hook, parallel to the hook provided by irt_ppapi.c.

(*) A "for the browser" library, that the browser-tester
and the PNaCl packager will include for PNaCl-in-the-browser.
This is still called "libpnacl_irt_shim.a" so that we don't
need to change the in-browser linker's commandline. However,
it will be placed in a different directory so that the
Chrome PNaCl packager can pick it up separately from
the AOT library. This for-browser library uses the new hook.

(*) A "AOT" library, that will go into the SDK for offline
pexe -> nexe translation. Still called "libpnacl_irt_shim.a"
as well, confusingly enough, so that we don't need to change
the pnacl-nativeld.py commandlines. Placed in a different
directory from the for-browser library. Does not use the
new hook, so that it only depends on stable interfaces.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=3783
R=binji@chromium.org, dmichael@chromium.org, mseaborn@chromium.org

Review URL: https://codereview.chromium.org/164373010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255807 0039d316-1c4b-4281-b951-d872f2087c98

11 files changed, 247 insertions, 80 deletions

diff --git a/ppapi/native_client/native_client.gyp b/ppapi/native_client/native_client.gyp
index d8db2ad..5621cbc 100644
--- a/ppapi/native_client/native_client.gyp
+++ b/ppapi/native_client/native_client.gyp
@@ -119,6 +119,7 @@
             'link_flags': [
               '-Wl,--start-group',
               '-lirt_browser',
+              '-lpnacl_irt_shim_for_irt',
               '-lppapi_proxy_nacl',
               '-lppapi_ipc_nacl',
               '-lppapi_shared_nacl',
@@ -172,6 +173,7 @@
                   '>(tc_lib_dir_irt64)/libipc_nacl.a',
                   '>(tc_lib_dir_irt64)/libbase_nacl.a',
                   '>(tc_lib_dir_irt64)/libirt_browser.a',
+                  '>(tc_lib_dir_irt64)/libpnacl_irt_shim_for_irt.a',
                   '>(tc_lib_dir_irt64)/libshared_memory_support_nacl.a',
                   '>(tc_lib_dir_irt64)/libsrpc.a',
                   '>(tc_lib_dir_irt64)/libplatform.a',
@@ -192,6 +194,7 @@
                   '>(tc_lib_dir_irt32)/libipc_nacl.a',
                   '>(tc_lib_dir_irt32)/libbase_nacl.a',
                   '>(tc_lib_dir_irt32)/libirt_browser.a',
+                  '>(tc_lib_dir_irt32)/libpnacl_irt_shim_for_irt.a',
                   '>(tc_lib_dir_irt32)/libshared_memory_support_nacl.a',
                   '>(tc_lib_dir_irt32)/libsrpc.a',
                   '>(tc_lib_dir_irt32)/libplatform.a',
@@ -214,6 +217,7 @@
                   '>(tc_lib_dir_irt_arm)/libipc_nacl.a',
                   '>(tc_lib_dir_irt_arm)/libbase_nacl.a',
                   '>(tc_lib_dir_irt_arm)/libirt_browser.a',
+                  '>(tc_lib_dir_irt_arm)/libpnacl_irt_shim_for_irt.a',
                   '>(tc_lib_dir_irt_arm)/libshared_memory_support_nacl.a',
                   '>(tc_lib_dir_irt_arm)/libsrpc.a',
                   '>(tc_lib_dir_irt_arm)/libplatform.a',
@@ -236,6 +240,7 @@
                   '>(tc_lib_dir_irt_mips)/libipc_nacl.a',
                   '>(tc_lib_dir_irt_mips)/libbase_nacl.a',
                   '>(tc_lib_dir_irt_mips)/libirt_browser.a',
+                  '>(tc_lib_dir_irt_mips)/libpnacl_irt_shim_for_irt.a',
                   '>(tc_lib_dir_irt_mips)/libshared_memory_support_nacl.a',
                   '>(tc_lib_dir_irt_mips)/libsrpc.a',
                   '>(tc_lib_dir_irt_mips)/libplatform.a',
@@ -246,6 +251,7 @@
             ],
           },
           'dependencies': [
+            'src/untrusted/pnacl_irt_shim/pnacl_irt_shim.gyp:pnacl_irt_shim_for_irt',
             '../ppapi_proxy_nacl.gyp:ppapi_proxy_nacl',
             '../ppapi_ipc_nacl.gyp:ppapi_ipc_nacl',
             '../ppapi_shared_nacl.gyp:ppapi_shared_nacl',
diff --git a/ppapi/native_client/src/untrusted/pnacl_irt_shim/irt_shim_ppapi.c b/ppapi/native_client/src/untrusted/pnacl_irt_shim/irt_shim_ppapi.c
new file mode 100644
index 0000000..eeca8cf
--- /dev/null
+++ b/ppapi/native_client/src/untrusted/pnacl_irt_shim/irt_shim_ppapi.c
@@ -0,0 +1,79 @@
+/*
+ * Copyright 2014 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.
+ */
+
+#include "ppapi/native_client/src/untrusted/pnacl_irt_shim/irt_shim_ppapi.h"
+
+#include "native_client/src/untrusted/irt/irt.h"
+#include "ppapi/nacl_irt/irt_ppapi.h"
+#include "ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_shim.h"
+#include "ppapi/proxy/plugin_main_irt.h"
+
+/*
+ * Defines a version of the version irt_ppapi_start and of the irt_ppapihook
+ * that returns a shimmed GetInterface for PNaCl.
+ *
+ * The hook will be linked into the IRT but it is considered unstable.
+ * Stable nexes should not use that IRT hook (and a filter prevents
+ * it from being used). Instead PNaCl nexes should embed the
+ * irt_shim_ppapi_start and the shim functions directly into the nexe
+ * for ABI stability.
+ */
+
+static struct PP_StartFunctions g_user_start_functions;
+
+static int32_t shim_PPPInitializeModule(PP_Module module_id,
+                                        PPB_GetInterface get_browser_intf) {
+  /* Record the original PPB_GetInterface and provide a shimmed one. */
+  __set_real_Pnacl_PPBGetInterface(get_browser_intf);
+  return (*g_user_start_functions.PPP_InitializeModule)(
+      module_id,
+      &__Pnacl_PPBGetInterface);
+}
+
+static void shim_PPPShutdownModule() {
+  (*g_user_start_functions.PPP_ShutdownModule)();
+}
+
+#ifdef PNACL_SHIM_AOT
+ /*
+  * This will be discovered and set by the shim, since we cannot link
+  * against the IRT directly in the AOT library.
+  */
+int (*real_irt_ppapi_start)(const struct PP_StartFunctions *) = NULL;
+#else
+ /*
+  * Otherwise, when linking directly into the IRT, we can refer to the
+  * real irt_ppapi_start from irt_ppapi.
+  */
+extern int irt_ppapi_start(const struct PP_StartFunctions *);
+static int (* const real_irt_ppapi_start)(const struct PP_StartFunctions *) =
+    &irt_ppapi_start;
+#endif
+
+int irt_shim_ppapi_start(const struct PP_StartFunctions *funcs) {
+  g_user_start_functions = *funcs;
+  /*
+   * Record the original PPP_GetInterface and provide a shimmed one
+   * via wrapped_ppapi_methods.
+   */
+  const struct PP_StartFunctions wrapped_ppapi_methods = {
+    shim_PPPInitializeModule,
+    shim_PPPShutdownModule,
+    __Pnacl_PPPGetInterface
+  };
+  __set_real_Pnacl_PPPGetInterface(g_user_start_functions.PPP_GetInterface);
+  /*
+   * Invoke the IRT's ppapi_start interface with the wrapped interface.
+   */
+  return (*real_irt_ppapi_start)(&wrapped_ppapi_methods);
+}
+
+#ifndef PNACL_SHIM_AOT
+const struct nacl_irt_ppapihook nacl_irt_ppapihook_pnacl_private = {
+  irt_shim_ppapi_start,
+  PpapiPluginRegisterThreadCreator,
+};
+#endif
diff --git a/ppapi/native_client/src/untrusted/pnacl_irt_shim/irt_shim_ppapi.h b/ppapi/native_client/src/untrusted/pnacl_irt_shim/irt_shim_ppapi.h
new file mode 100644
index 0000000..5654dce
--- /dev/null
+++ b/ppapi/native_client/src/untrusted/pnacl_irt_shim/irt_shim_ppapi.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright 2014 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.
+ */
+
+#ifndef PPAPI_NATIVE_CLIENT_SRC_UNTRUSTED_PNACL_IRT_SHIM_IRT_SHIM_PPAPI_H_
+#define PPAPI_NATIVE_CLIENT_SRC_UNTRUSTED_PNACL_IRT_SHIM_IRT_SHIM_PPAPI_H_
+
+#include "ppapi/nacl_irt/irt_ppapi.h"
+
+#ifdef PNACL_SHIM_AOT
+
+/* Given a hook for the real irt ppapi start, get a shimmed ppapi_start. */
+extern int (*real_irt_ppapi_start)(const struct PP_StartFunctions *);
+extern int irt_shim_ppapi_start(const struct PP_StartFunctions *funcs);
+
+#else
+
+/*
+ * A private version of the NACL_IRT_PPAPIHOOK_v0_1, which provides
+ * PNaCl with shimmed IRT interfaces.
+ */
+#define NACL_IRT_PPAPIHOOK_PNACL_PRIVATE_v0_1   \
+  "nacl-irt-ppapihook-pnacl-private-0.1"
+extern const struct nacl_irt_ppapihook nacl_irt_ppapihook_pnacl_private;
+
+#endif
+
+#endif
diff --git a/ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_irt_shim.gyp b/ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_irt_shim.gyp
index 7f2b677..ba115dd 100644
--- a/ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_irt_shim.gyp
+++ b/ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_irt_shim.gyp
@@ -8,7 +8,8 @@
   ],
   'targets': [
     {
-      'target_name': 'pnacl_irt_shim',
+      # The full library, which PNaCl uses for offline .pexe -> .nexe.
+      'target_name': 'pnacl_irt_shim_aot',
       'type': 'none',
       'variables': {
         'nlib_target': 'libpnacl_irt_shim.a',
@@ -25,6 +26,7 @@
         'enable_arm': 1,
         'enable_mips': 1,
         'sources': [
+          'irt_shim_ppapi.c',
           'pnacl_shim.c',
           'shim_entry.c',
           'shim_ppapi.c',
@@ -32,6 +34,68 @@
         'extra_args': [
           '--strip-debug',
         ],
+        # Indicate that shim should not depend on unstable IRT hook interface.
+        'compile_flags': [
+          '-DPNACL_SHIM_AOT',
+        ],
+      },
+      'dependencies': [
+        '<(DEPTH)/native_client/tools.gyp:prep_toolchain',
+      ],
+    },
+    # Smaller shim library for PNaCl in-browser translation.
+    # Uses an unstable IRT hook interface to get the shim from the IRT itself.
+    # If we ever change that hook interface or change the in-IRT shim's ABI,
+    # we would need to clear the translation cache to match the new IRT.
+    {
+      'target_name': 'pnacl_irt_shim_browser',
+      'type': 'none',
+      'variables': {
+        # Same name as pnacl_irt_shim_aot, so that we don't need to change
+        # the linker commandlines, but output to the "for_browser" directory,
+        # and have the pnacl_support_extension copy from that directory.
+        'nlib_target': 'libpnacl_irt_shim.a',
+        'out_pnacl_newlib_arm': '>(tc_lib_dir_pnacl_translate)/lib-arm/for_browser/>(nlib_target)',
+        'out_pnacl_newlib_x86_32': '>(tc_lib_dir_pnacl_translate)/lib-x86-32/for_browser/>(nlib_target)',
+        'out_pnacl_newlib_x86_64': '>(tc_lib_dir_pnacl_translate)/lib-x86-64/for_browser/>(nlib_target)',
+        'out_pnacl_newlib_mips': '>(tc_lib_dir_pnacl_translate)/lib-mips32/for_browser/>(nlib_target)',
+        'build_glibc': 0,
+        'build_newlib': 0,
+        'build_pnacl_newlib': 1,
+        'pnacl_native_biased': 1,
+        'enable_x86_32': 1,
+        'enable_x86_64': 1,
+        'enable_arm': 1,
+        'enable_mips': 1,
+        'sources': [
+          'shim_entry.c',
+          'shim_ppapi.c',
+        ],
+        'extra_args': [
+          '--strip-debug',
+        ],
+      },
+      'dependencies': [
+        '<(DEPTH)/native_client/tools.gyp:prep_toolchain',
+      ],
+    },
+    {
+      # Second half of shim library for PNaCl in-browser translation.
+      # This half goes into the IRT and is returned by the unstable
+      # IRT hook interface.
+      'target_name': 'pnacl_irt_shim_for_irt',
+      'type': 'none',
+      'variables': {
+        'nlib_target': 'libpnacl_irt_shim_for_irt.a',
+        'build_glibc': 0,
+        'build_newlib': 0,
+        # Unlike the above, build this the way the IRT is built so that the
+        # output library directories match the IRT linking search paths.
+        'build_irt': 1,
+        'sources': [
+          'irt_shim_ppapi.c',
+          'pnacl_shim.c',
+        ],
       },
       'dependencies': [
         '<(DEPTH)/native_client/tools.gyp:prep_toolchain',
diff --git a/ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_entry.c b/ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_entry.c
index 4c93c9e..561b0cc 100644
--- a/ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_entry.c
+++ b/ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_entry.c
@@ -28,15 +28,15 @@ void _pnacl_wrapper_start(uint32_t *info) {
 
   if (entry != NULL) {
     /*
-     * Save the real irt interface.
+     * Save the real irt interface query function.
      */
-    __pnacl_real_irt_interface = (TYPE_nacl_irt_query) entry->a_un.a_val;
+    __pnacl_real_irt_query_func = (TYPE_nacl_irt_query) entry->a_un.a_val;
 
     /*
      * Overwrite the auxv slot with the pnacl IRT shim query function.
      */
     entry->a_type = AT_SYSINFO;
-    entry->a_un.a_val = (uintptr_t) __pnacl_irt_interface_wrapper;
+    entry->a_un.a_val = (uintptr_t) __pnacl_wrap_irt_query_func;
   }
 
   /* If entry is NULL still allow startup to continue.  It may be the case
diff --git a/ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_ppapi.c b/ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_ppapi.c
index 5e111c1..76952af 100644
--- a/ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_ppapi.c
+++ b/ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_ppapi.c
@@ -10,6 +10,7 @@
 #include "native_client/src/untrusted/irt/irt.h"
 #include "ppapi/nacl_irt/irt_ppapi.h"
 #include "ppapi/native_client/src/shared/ppapi_proxy/ppruntime.h"
+#include "ppapi/native_client/src/untrusted/pnacl_irt_shim/irt_shim_ppapi.h"
 #include "ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_shim.h"
 
 /* Use local strcmp to avoid dependency on libc. */
@@ -18,55 +19,9 @@ static int mystrcmp(const char* s1, const char *s2) {
   return *(--s1) - *(--s2);
 }
 
-TYPE_nacl_irt_query __pnacl_real_irt_interface = NULL;
+TYPE_nacl_irt_query __pnacl_real_irt_query_func = NULL;
 
-/*
- * These remember the interface pointers the user registers by calling the
- * IRT entry point.
- */
-static struct PP_StartFunctions user_start_functions;
-
-static int32_t wrap_PPPInitializeModule(PP_Module module_id,
-                                        PPB_GetInterface get_browser_intf) {
-  __set_real_Pnacl_PPBGetInterface(get_browser_intf);
-  /*
-   * Calls from user code to the PPB interfaces pass through here and may
-   * require shims to convert the ABI.
-   */
-  return (*user_start_functions.PPP_InitializeModule)(module_id,
-                                                      &__Pnacl_PPBGetInterface);
-}
-
-static void wrap_PPPShutdownModule() {
-  (*user_start_functions.PPP_ShutdownModule)();
-}
-
-static const struct PP_StartFunctions wrapped_ppapi_methods = {
-  wrap_PPPInitializeModule,
-  wrap_PPPShutdownModule,
-  /*
-   * Calls from the IRT to the user plugin pass through here and may require
-   * shims to convert the ABI.
-   */
-  __Pnacl_PPPGetInterface
-};
-
-static struct nacl_irt_ppapihook real_irt_ppapi_hook;
-
-static int wrap_ppapi_start(const struct PP_StartFunctions *funcs) {
-  /*
-   * Save the user's real bindings for the start functions.
-   */
-  user_start_functions = *funcs;
-  __set_real_Pnacl_PPPGetInterface(user_start_functions.PPP_GetInterface);
-
-  /*
-   * Invoke the IRT's ppapi_start interface with the wrapped interface.
-   */
-  return (*real_irt_ppapi_hook.ppapi_start)(&wrapped_ppapi_methods);
-}
-
-size_t __pnacl_irt_interface_wrapper(const char *interface_ident,
+size_t __pnacl_wrap_irt_query_func(const char *interface_ident,
                                      void *table, size_t tablesize) {
   /*
    * Note there is a benign race in initializing the wrapper.
@@ -79,23 +34,39 @@ size_t __pnacl_irt_interface_wrapper(const char *interface_ident,
     /*
      * The interface is not wrapped, so use the real interface.
      */
-    return (*__pnacl_real_irt_interface)(interface_ident, table, tablesize);
+    return (*__pnacl_real_irt_query_func)(interface_ident, table, tablesize);
   }
-  if ((*__pnacl_real_irt_interface)(NACL_IRT_PPAPIHOOK_v0_1,
-                                    &real_irt_ppapi_hook,
-                                    sizeof real_irt_ppapi_hook) !=
+#ifndef PNACL_SHIM_AOT
+  /*
+   * For PNaCl in-the-browser, redirect to using
+   * NACL_IRT_PPAPIHOOK_PNACL_PRIVATE_v0_1 instead of NACL_IRT_PPAPIHOOK_v0_1.
+   */
+  return (*__pnacl_real_irt_query_func)(NACL_IRT_PPAPIHOOK_PNACL_PRIVATE_v0_1,
+                                        table, tablesize);
+#else
+  /*
+   * For offline generated nexes, avoid depending on the private
+   * NACL_IRT_PPAPIHOOK_PNACL_PRIVATE_v0_1 interface, and just do the
+   * overriding here manually.
+   */
+  struct nacl_irt_ppapihook real_irt_ppapi_hook;
+  if ((*__pnacl_real_irt_query_func)(NACL_IRT_PPAPIHOOK_v0_1,
+                                     &real_irt_ppapi_hook,
+                                     sizeof real_irt_ppapi_hook) !=
       sizeof real_irt_ppapi_hook) {
     return 0;
   }
+  real_irt_ppapi_start = real_irt_ppapi_hook.ppapi_start;
   /*
    * Copy the interface structure into the client.
    */
   struct nacl_irt_ppapihook *dest = table;
   if (sizeof *dest <= tablesize) {
-    dest->ppapi_start = wrap_ppapi_start;
+    dest->ppapi_start = irt_shim_ppapi_start;
     dest->ppapi_register_thread_creator =
         real_irt_ppapi_hook.ppapi_register_thread_creator;
     return sizeof *dest;
   }
   return 0;
+#endif
 }
diff --git a/ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_ppapi.h b/ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_ppapi.h
index d5b7e32..6231196 100644
--- a/ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_ppapi.h
+++ b/ppapi/native_client/src/untrusted/pnacl_irt_shim/shim_ppapi.h
@@ -4,8 +4,8 @@
  * found in the LICENSE file.
  */
 
-#ifndef NATIVE_CLIENT_SRC_UNTRUSTED_PNACL_IRT_SHIM_SHIM_PPAPI_H_
-#define NATIVE_CLIENT_SRC_UNTRUSTED_PNACL_IRT_SHIM_SHIM_PPAPI_H_ 1
+#ifndef PPAPI_NATIVE_CLIENT_SRC_UNTRUSTED_PNACL_IRT_SHIM_SHIM_PPAPI_H_
+#define PPAPI_NATIVE_CLIENT_SRC_UNTRUSTED_PNACL_IRT_SHIM_SHIM_PPAPI_H_ 1
 
 #include <stddef.h>
 #include "native_client/src/untrusted/irt/irt.h"
@@ -13,9 +13,12 @@
 /*
  * Remembers the IRT's true interface query function.
  */
-extern TYPE_nacl_irt_query __pnacl_real_irt_interface;
+extern TYPE_nacl_irt_query __pnacl_real_irt_query_func;
 
-size_t __pnacl_irt_interface_wrapper(const char *interface_ident,
-                                     void *table, size_t tablesize);
+/*
+ * Provides a wrapped query function.
+ */
+size_t __pnacl_wrap_irt_query_func(const char *interface_ident,
+                                   void *table, size_t tablesize);
 
-#endif  /* NATIVE_CLIENT_SRC_UNTRUSTED_PNACL_IRT_SHIM_SHIM_PPAPI_H_ */
+#endif  /* PPAPI_NATIVE_CLIENT_SRC_UNTRUSTED_PNACL_IRT_SHIM_SHIM_PPAPI_H_ */
diff --git a/ppapi/native_client/src/untrusted/pnacl_support_extension/pnacl_support_extension.gyp b/ppapi/native_client/src/untrusted/pnacl_support_extension/pnacl_support_extension.gyp
index fa57030..0657e58 100644
--- a/ppapi/native_client/src/untrusted/pnacl_support_extension/pnacl_support_extension.gyp
+++ b/ppapi/native_client/src/untrusted/pnacl_support_extension/pnacl_support_extension.gyp
@@ -15,7 +15,7 @@
     'conditions': [
       ['disable_nacl==0 and disable_pnacl==0 and disable_nacl_untrusted==0', {
         'dependencies': [
-          '../../../../../ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_irt_shim.gyp:pnacl_irt_shim',
+          '../../../../../ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_irt_shim.gyp:pnacl_irt_shim_browser',
           '../../../../../native_client/tools.gyp:prep_toolchain',
         ],
         'sources': [
@@ -54,14 +54,14 @@
                       '<(PRODUCT_DIR)/pnacl/pnacl_public_x86_64_pnacl_llc_nexe',
                     ],
                     'inputs': [
-                      '>(tc_lib_dir_pnacl_translate)/lib-x86-32/libpnacl_irt_shim.a',
-                      '>(tc_lib_dir_pnacl_translate)/lib-x86-64/libpnacl_irt_shim.a',
+                      '>(tc_lib_dir_pnacl_translate)/lib-x86-32/for_browser/libpnacl_irt_shim.a',
+                      '>(tc_lib_dir_pnacl_translate)/lib-x86-64/for_browser/libpnacl_irt_shim.a',
                     ],
                     'variables': {
                       'lib_overrides': [
                         # Use the two freshly generated shims.
-                        '--lib_override=ia32,>(tc_lib_dir_pnacl_translate)/lib-x86-32/libpnacl_irt_shim.a',
-                        '--lib_override=x64,>(tc_lib_dir_pnacl_translate)/lib-x86-64/libpnacl_irt_shim.a',
+                        '--lib_override=ia32,>(tc_lib_dir_pnacl_translate)/lib-x86-32/for_browser/libpnacl_irt_shim.a',
+                        '--lib_override=x64,>(tc_lib_dir_pnacl_translate)/lib-x86-64/for_browser/libpnacl_irt_shim.a',
                       ],
                     },
                 }],
@@ -80,12 +80,12 @@
                           '<(PRODUCT_DIR)/pnacl/pnacl_public_arm_pnacl_llc_nexe',
                         ],
                         'inputs': [
-                          '>(tc_lib_dir_pnacl_translate)/lib-arm/libpnacl_irt_shim.a',
+                          '>(tc_lib_dir_pnacl_translate)/lib-arm/for_browser/libpnacl_irt_shim.a',
                         ],
                         'variables': {
                           'lib_overrides': [
                             # Use the freshly generated shim.
-                            '--lib_override=arm,>(tc_lib_dir_pnacl_translate)/lib-arm/libpnacl_irt_shim.a',
+                            '--lib_override=arm,>(tc_lib_dir_pnacl_translate)/lib-arm/for_browser/libpnacl_irt_shim.a',
                           ],
                         },
                       }],
@@ -101,12 +101,12 @@
                           '<(PRODUCT_DIR)/pnacl/pnacl_public_mips32_llc_nexe',
                         ],
                         'inputs': [
-                          '>(tc_lib_dir_pnacl_translate)/lib-mips32/libpnacl_irt_shim.a',
+                          '>(tc_lib_dir_pnacl_translate)/lib-mips32/for_browser/libpnacl_irt_shim.a',
                         ],
                         'variables': {
                           'lib_overrides': [
                             # Use the freshly generated shim.
-                            '--lib_override=mipsel,>(tc_lib_dir_pnacl_translate)/lib-mips32/libpnacl_irt_shim.a',
+                            '--lib_override=mipsel,>(tc_lib_dir_pnacl_translate)/lib-mips32/for_browser/libpnacl_irt_shim.a',
                           ],
                         },
                       }],
@@ -122,12 +122,12 @@
                           '<(PRODUCT_DIR)/pnacl/pnacl_public_x86_32_pnacl_llc_nexe',
                         ],
                         'inputs': [
-                          '>(tc_lib_dir_pnacl_translate)/lib-x86-32/libpnacl_irt_shim.a',
+                          '>(tc_lib_dir_pnacl_translate)/lib-x86-32/for_browser/libpnacl_irt_shim.a',
                         ],
                         'variables': {
                           'lib_overrides': [
                             # Use the freshly generated shim.
-                            '--lib_override=ia32,>(tc_lib_dir_pnacl_translate)/lib-x86-32/libpnacl_irt_shim.a',
+                            '--lib_override=ia32,>(tc_lib_dir_pnacl_translate)/lib-x86-32/for_browser/libpnacl_irt_shim.a',
                           ],
                         },
                       }],
@@ -143,12 +143,12 @@
                           '<(PRODUCT_DIR)/pnacl/pnacl_public_x86_64_pnacl_llc_nexe',
                         ],
                         'inputs': [
-                          '>(tc_lib_dir_pnacl_translate)/lib-x86-64/libpnacl_irt_shim.a',
+                          '>(tc_lib_dir_pnacl_translate)/lib-x86-64/for_browser/libpnacl_irt_shim.a',
                         ],
                         'variables': {
                           'lib_overrides': [
                             # Use the freshly generated shim.
-                            '--lib_override=x64,>(tc_lib_dir_pnacl_translate)/lib-x86-64/libpnacl_irt_shim.a',
+                            '--lib_override=x64,>(tc_lib_dir_pnacl_translate)/lib-x86-64/for_browser/libpnacl_irt_shim.a',
                           ],
                         },
                       }],
diff --git a/ppapi/ppapi_nacl.gyp b/ppapi/ppapi_nacl.gyp
index ca016ed1..20d40c3 100644
--- a/ppapi/ppapi_nacl.gyp
+++ b/ppapi/ppapi_nacl.gyp
@@ -186,7 +186,7 @@
           },
           # Shim is a dependency for the nexe because we pre-translate.
           'dependencies': [
-            '<(DEPTH)/ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_irt_shim.gyp:pnacl_irt_shim',
+            '<(DEPTH)/ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_irt_shim.gyp:pnacl_irt_shim_aot',
           ],
          'actions': [
             {
@@ -214,7 +214,7 @@
           },
           # Shim is a dependency for the nexe because we pre-translate.
           'dependencies': [
-            '<(DEPTH)/ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_irt_shim.gyp:pnacl_irt_shim',
+            '<(DEPTH)/ppapi/native_client/src/untrusted/pnacl_irt_shim/pnacl_irt_shim.gyp:pnacl_irt_shim_aot',
           ],
           'actions': [
             {
diff --git a/ppapi/proxy/DEPS b/ppapi/proxy/DEPS
index 3920896..0c13d6b 100644
--- a/ppapi/proxy/DEPS
+++ b/ppapi/proxy/DEPS
@@ -20,5 +20,7 @@ include_rules = [
   "+native_client/src/shared/srpc/nacl_srpc.h",
   "+native_client/src/untrusted/irt/irt.h",
   "+native_client/src/untrusted/irt/irt_private.h",
+  # The IRT also needs to know the sysconf enums.
+  "+native_client/src/trusted/service_runtime/include/sys/unistd.h",
 ]
 
diff --git a/ppapi/proxy/irt_ppapi.c b/ppapi/proxy/irt_ppapi.c
index 24dafdb..8bf1233 100644
--- a/ppapi/proxy/irt_ppapi.c
+++ b/ppapi/proxy/irt_ppapi.c
@@ -5,14 +5,16 @@
  */
 
 #include "native_client/src/public/irt_core.h"
+#include "native_client/src/trusted/service_runtime/include/sys/unistd.h"
 #include "native_client/src/untrusted/irt/irt.h"
 #include "native_client/src/untrusted/irt/irt_private.h"
 #include "ppapi/nacl_irt/irt_ppapi.h"
+#include "ppapi/native_client/src/untrusted/pnacl_irt_shim/irt_shim_ppapi.h"
 #include "ppapi/proxy/plugin_main_irt.h"
 
-struct PP_StartFunctions g_pp_functions;
+static struct PP_StartFunctions g_pp_functions;
 
-static int irt_ppapi_start(const struct PP_StartFunctions* funcs) {
+int irt_ppapi_start(const struct PP_StartFunctions* funcs) {
   /* Disable NaCl's open_resource() interface on this thread. */
   g_is_main_thread = 1;
 
@@ -38,9 +40,19 @@ static const struct nacl_irt_ppapihook nacl_irt_ppapihook = {
   PpapiPluginRegisterThreadCreator,
 };
 
+static int ppapihook_pnacl_private_filter(void) {
+  int pnacl_mode = sysconf(NACL_ABI__SC_NACL_PNACL_MODE);
+  if (pnacl_mode == -1)
+    return 0;
+  return pnacl_mode;
+}
+
 static const struct nacl_irt_interface irt_interfaces[] = {
   { NACL_IRT_PPAPIHOOK_v0_1, &nacl_irt_ppapihook, sizeof(nacl_irt_ppapihook),
     NULL },
+  { NACL_IRT_PPAPIHOOK_PNACL_PRIVATE_v0_1,
+    &nacl_irt_ppapihook_pnacl_private, sizeof(nacl_irt_ppapihook_pnacl_private),
+    ppapihook_pnacl_private_filter },
 };
 
 static size_t chrome_irt_query(const char* interface_ident,