For building v8 using gn on aix_ppc64, linux_s390x and linux_ppc64(both LE and BE).

Also add support for host_byteorder logic which is introduced in - https://codereview.chromium.org/2815453004/

Chromium_BUG=706728
R=machenbach@chromium.org, dpranke@chromium.org, adamk@chromium.org

Review-Url: https://codereview.chromium.org/2809963004
Cr-Commit-Position: refs/heads/master@{#45268}

.gn

@@ -21,7 +21,5 @@ check_targets = []
 # These are the list of GN files that run exec_script. This whitelist exists
 # to force additional review for new uses of exec_script, which is strongly
 # discouraged except for gypi_to_gn calls.
-exec_script_whitelist = build_dotfile_settings.exec_script_whitelist + [
-                          "//test/test262/BUILD.gn",
-                          "//BUILD.gn",
-                        ]
+exec_script_whitelist =
+    build_dotfile_settings.exec_script_whitelist + [ "//test/test262/BUILD.gn" ]

BUILD.gn

@@ -5,6 +5,7 @@
 import("//build/config/android/config.gni")
 import("//build/config/arm.gni")
 import("//build/config/dcheck_always_on.gni")
+import("//build/config/host_byteorder.gni")
 import("//build/config/mips.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 
@@ -107,19 +108,6 @@ declare_args() {
   v8_enable_gdbjit = ((v8_current_cpu == "x86" || v8_current_cpu == "x64" ||
                        v8_current_cpu == "x87") && (is_linux || is_mac)) ||
                      (v8_current_cpu == "ppc64" && is_linux)
-
-  # Set v8_host_byteorder
-  v8_host_byteorder = "little"
-
-  # ppc64 can be either BE or LE
-  if (host_cpu == "ppc64") {
-    v8_host_byteorder =
-        exec_script("//tools/get_byteorder.py", [], "trim string")
-  }
-  if (host_cpu == "ppc" || host_cpu == "s390" || host_cpu == "s390x" ||
-      host_cpu == "mips" || host_cpu == "mips64") {
-    v8_host_byteorder = "big"
-  }
 }
 
 # Derived defaults.
@@ -379,7 +367,7 @@ config("toolchain") {
     if (v8_current_cpu == "s390x") {
       defines += [ "V8_TARGET_ARCH_S390X" ]
     }
-    if (v8_host_byteorder == "little") {
+    if (host_byteorder == "little") {
       defines += [ "V8_TARGET_ARCH_S390_LE_SIM" ]
     } else {
       cflags += [ "-march=z196" ]
@@ -390,9 +378,9 @@ config("toolchain") {
     if (v8_current_cpu == "ppc64") {
       defines += [ "V8_TARGET_ARCH_PPC64" ]
     }
-    if (v8_host_byteorder == "little") {
+    if (host_byteorder == "little") {
       defines += [ "V8_TARGET_ARCH_PPC_LE" ]
-    } else if (v8_host_byteorder == "big") {
+    } else if (host_byteorder == "big") {
       defines += [ "V8_TARGET_ARCH_PPC_BE" ]
       if (current_os == "aix") {
         cflags += [
@@ -406,6 +394,7 @@ config("toolchain") {
       }
     }
   }
+
   if (v8_current_cpu == "x86") {
     defines += [ "V8_TARGET_ARCH_IA32" ]
     if (is_win) {
@@ -2508,6 +2497,16 @@ v8_component("v8_libbase") {
       "src/base/platform/platform-linux.cc",
     ]
 
+    libs = [
+      "dl",
+      "rt",
+    ]
+  } else if (current_os == "aix") {
+    sources += [
+      "src/base/debug/stack_trace_posix.cc",
+      "src/base/platform/platform-aix.cc",
+    ]
+
     libs = [
       "dl",
       "rt",

src/base/build_config.h

@@ -35,7 +35,7 @@
 #define V8_HOST_ARCH_32_BIT 1
 #elif defined(__PPC__) || defined(_ARCH_PPC)
 #define V8_HOST_ARCH_PPC 1
-#if defined(__PPC64__) || defined(_ARCH_PPC64)
+#if defined(__PPC64__) || defined(_ARCH_PPC64) || defined(_ARCH_PPCGR)
 #define V8_HOST_ARCH_64_BIT 1
 #else
 #define V8_HOST_ARCH_32_BIT 1
@@ -91,6 +91,8 @@
 #define V8_TARGET_ARCH_MIPS64 1
 #elif defined(__MIPSEB__) || defined(__MIPSEL__)
 #define V8_TARGET_ARCH_MIPS 1
+#elif defined(_ARCH_PPC)
+#define V8_TARGET_ARCH_PPC 1
 #else
 #error Target architecture was not detected as supported by v8
 #endif
@@ -181,6 +183,8 @@
 #endif
 #elif V8_TARGET_ARCH_X87
 #define V8_TARGET_LITTLE_ENDIAN 1
+#elif __BIG_ENDIAN__  // FOR PPCGR on AIX
+#define V8_TARGET_BIG_ENDIAN 1
 #elif V8_TARGET_ARCH_PPC_LE
 #define V8_TARGET_LITTLE_ENDIAN 1
 #elif V8_TARGET_ARCH_PPC_BE

tools/get_byteorder.py

-#!/usr/bin/env python
-#
-# Copyright 2017 the V8 project authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-"""Get Byteorder of host architecture"""
-
-
-import sys
-
-def main():
-  print sys.byteorder
-  return 0
-
-if __name__ == '__main__':
-  sys.exit(main())