Handle ARM "ret void" and function alignment with proper padding.

pydir/run-pnacl-sz.py

 #!/usr/bin/env python2
 
 import argparse
 import itertools
 import os
 import re
 import subprocess
 import sys
 import tempfile
 
 from utils import shellcmd
 
+
+def TargetAssemblerFlags(target):
+  # TODO(stichnot): -triple=i686-nacl should be used for a
+  # sandboxing test.  This means there should be an args.sandbox
+  # argument that also gets passed through to pnacl-sz.
+  flags = { 'x8632': ['-triple=i686'],
+            'arm32': ['-triple=armv7a', '-mcpu=cortex-a9', '-mattr=+neon'] }
+  return flags[target]
+
+
+def TargetDisassemblerFlags(target):
+  flags = { 'x8632': ['-Mintel'],
+            'arm32': [] }
+  return flags[target]
+
+
 def main():
     """Run the pnacl-sz compiler on an llvm file.
 
     Takes an llvm input file, freezes it into a pexe file, converts
     it to a Subzero program, and finally compiles it.
     """
     argparser = argparse.ArgumentParser(
         description='    ' + main.__doc__,
         formatter_class=argparse.ArgumentDefaultsHelpFormatter)
     argparser.add_argument('--input', '-i', required=True,
@@ skipping 26 matching lines @@
                            help='Assemble the output')
     argparser.add_argument('--disassemble', required=False,
                            action='store_true',
                            help='Disassemble the assembled output')
     argparser.add_argument('--dis-flags', required=False,
                            action='append', default=[],
                            help='Add a disassembler flag')
     argparser.add_argument('--filetype', default='iasm', dest='filetype',
                            choices=['obj', 'asm', 'iasm'],
                            help='Output file type.  Default %(default)s.')
+    argparser.add_argument('--target', default='x8632', dest='target',
+                           choices=['x8632','arm32'],
+                           help='Target architecture.  Default %(default)s.')
     argparser.add_argument('--echo-cmd', required=False,
                            action='store_true',
                            help='Trace command that generates ICE instructions')
     argparser.add_argument('--args', '-a', nargs=argparse.REMAINDER,
                            default=[],
                            help='Remaining arguments are passed to pnacl-sz')
 
     args = argparser.parse_args()
     pnacl_bin_path = args.pnacl_bin_path
     llfile = args.input
 
     if args.llvm and args.llvm_source:
       raise RuntimeError("Can't specify both '--llvm' and '--llvm-source'")
 
     if args.llvm_source and args.no_local_syms:
       raise RuntimeError("Can't specify both '--llvm-source' and " +
                          "'--no-local-syms'")
 
     cmd = []
     if not args.llvm_source:
       cmd = [os.path.join(pnacl_bin_path, 'llvm-as'), llfile, '-o', '-', '|',
              os.path.join(pnacl_bin_path, 'pnacl-freeze')]
       if not args.no_local_syms:
         cmd += ['--allow-local-symbol-tables']
       cmd += ['|']
     cmd += [args.pnacl_sz]
+    cmd += ['--target', args.target]
     if args.insts:
       # If the tests are based on '-verbose inst' output, force
       # single-threaded translation because dump output does not get
       # reassembled into order.
       cmd += ['-verbose', 'inst', '-notranslate', '-threads=0']
     if not args.llvm_source:
       cmd += ['--bitcode-format=pnacl']
       if not args.no_local_syms:
         cmd += ['--allow-local-symbol-tables']
     if args.llvm or args.llvm_source:
       cmd += ['--build-on-read=0']
     else:
       cmd += ['--build-on-read=1']
     cmd += ['--filetype=' + args.filetype]
     cmd += args.args
     if args.llvm_source:
       cmd += [llfile]
     asm_temp = None
     if args.assemble or args.disassemble:
       # On windows we may need to close the file first before it can be
       # re-opened by the other tools, so don't do delete-on-close,
       # and instead manually delete.
       asm_temp = tempfile.NamedTemporaryFile(delete=False)
       asm_temp.close()
     if args.assemble and args.filetype != 'obj':
-      cmd += ['|', os.path.join(pnacl_bin_path, 'llvm-mc'),
-              # TODO(stichnot): -triple=i686-nacl should be used for a
-              # sandboxing test.  This means there should be an args.sandbox
-              # argument that also gets passed through to pnacl-sz.
-              '-triple=i686',
-              '-filetype=obj', '-o', asm_temp.name]
+      cmd += (['|', os.path.join(pnacl_bin_path, 'llvm-mc')] +
+              TargetAssemblerFlags(args.target) +
+              ['-filetype=obj', '-o', asm_temp.name])
     elif asm_temp:
       cmd += ['-o', asm_temp.name]
     if args.disassemble:
       # Show wide instruction encodings, diassemble, and show relocs.
       cmd += (['&&', os.path.join(pnacl_bin_path, 'le32-nacl-objdump')] +
               args.dis_flags +
-              ['-w', '-d', '-r', '-Mintel', asm_temp.name])
+              ['-w', '-d', '-r'] + TargetDisassemblerFlags(args.target) +
+              [asm_temp.name])
 
     stdout_result = shellcmd(cmd, echo=args.echo_cmd)
     if not args.echo_cmd:
       sys.stdout.write(stdout_result)
     if asm_temp:
       os.remove(asm_temp.name)
 
 if __name__ == '__main__':
     main()