Bug 1480558 - part 4 - add icudata support for aarch64 windows; r=mshal

yasm doesn't support aarch64, and trying to use GNU as with an MSVC
build seems like sadness waiting to happen.  Instead, we'll generate our
own assembly file that armasm64 will accept.

build/autoconf/icu.m4

@@ -91,9 +91,16 @@ if test -n "$USE_ICU"; then
     AC_DEFINE(U_USING_ICU_NAMESPACE,0)
 
     if test -z "$MOZ_SYSTEM_ICU"; then
-        if test -z "$YASM" -a -z "$GNU_AS" -a "$COMPILE_ENVIRONMENT"; then
-            AC_MSG_ERROR([Building ICU requires either yasm or a GNU assembler. If you do not have either of those available for this platform you must use --without-intl-api])
-        fi
+        case "$OS_TARGET:$CPU_ARCH" in
+        WINNT:aarch64)
+            dnl we use non-yasm, non-GNU as solutions here.
+            ;;
+        *)
+            if test -z "$YASM" -a -z "$GNU_AS" -a "$COMPILE_ENVIRONMENT"; then
+                AC_MSG_ERROR([Building ICU requires either yasm or a GNU assembler. If you do not have either of those available for this platform you must use --without-intl-api])
+            fi
+            ;;
+        esac
         dnl We build ICU as a static library.
         AC_DEFINE(U_STATIC_IMPLEMENTATION)
     fi

config/external/icu/data/genicudata.py

@@ -0,0 +1,14 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+def main(output, data_file, data_symbol):
+    output.write('''    AREA .rdata,ALIGN=4,DATA,READONLY
+    EXPORT _{data_symbol}[DATA]
+_{data_symbol}
+    INCBIN {data_file}
+    END
+'''.format(data_file=data_file, data_symbol=data_symbol))

config/external/icu/data/moz.build

@@ -14,14 +14,25 @@ if CONFIG['OS_ARCH'] == 'WINNT':
 elif CONFIG['OS_ARCH'] == 'Darwin':
     ASFLAGS += ['-DPREFIX']
 
-ASFLAGS += [
+data_symbol = 'icudt%s_dat' % CONFIG['MOZ_ICU_VERSION']
+asflags = [
     '-DICU_DATA_FILE="%s"' % CONFIG['ICU_DATA_FILE'],
-    '-DICU_DATA_SYMBOL=icudt%s_dat' % CONFIG['MOZ_ICU_VERSION'],
+    '-DICU_DATA_SYMBOL=%s' % data_symbol,
 ]
 LOCAL_INCLUDES += ['.']
 
-if CONFIG['HAVE_YASM']:
+if CONFIG['OS_TARGET'] == 'WINNT' and CONFIG['CPU_ARCH'] == 'aarch64':
+    icudata = 'icudata.asm'
+    GENERATED_FILES += [icudata]
+    SOURCES += ['!%s' % icudata]
+    icudata = GENERATED_FILES[icudata]
+    icudata.script = 'genicudata.py'
+    icudata.inputs = [CONFIG['ICU_DATA_FILE']]
+    icudata.flags = [data_symbol]
+elif CONFIG['HAVE_YASM']:
     USE_YASM = True
     SOURCES += ['icudata.s']
+    ASFLAGS += asflags
 elif CONFIG['GNU_AS']:
     SOURCES += ['icudata_gas.S']
+    ASFLAGS += asflags