Subzero: Add Non-SFI support for x86-32.

pydir/szbuild.py

Index: pydir/szbuild.py
diff --git a/pydir/szbuild.py b/pydir/szbuild.py
index 37dbc6eaad8c123df3b6153650b2aa6b47fc1d06..a520d13d6efe68015eda44efd04aded2a2db48ab 100755
--- a/pydir/szbuild.py
+++ b/pydir/szbuild.py
@@ -85,6 +85,8 @@ def AddOptionalArgs(argparser):
                            help='Output file type.  Default %(default)s.')
     argparser.add_argument('--sandbox', dest='sandbox', action='store_true',
                            help='Enable sandboxing in the translator')
+    argparser.add_argument('--nonsfi', dest='nonsfi', action='store_true',
+                           help='Enable Non-SFI in the translator')
     argparser.add_argument('--enable-block-profile',
                            dest='enable_block_profile', action='store_true',
                            help='Enable basic block profiling.')
@@ -183,13 +185,15 @@ def ProcessPexe(args, pexe, exe):
     opt_level = args.optlevel
     opt_level_map = { 'm1':'0', '-1':'0', '0':'0', '1':'1', '2':'2' }
     hybrid = args.include or args.exclude
+    sb_or_nonsfi = args.sandbox or args.nonsfi
 
     if hybrid and (args.force or
                    NewerThanOrNotThere(pexe, obj_llc) or
                    NewerThanOrNotThere(llcbin, obj_llc)):
         arch = {
           'arm32': 'armv7' if args.sandbox else 'arm-nonsfi',
-          'x8632': 'x86-32' if args.sandbox else 'x86-32-linux',
+          'x8632': 'x86-32' if args.sandbox else

[John, 2015/12/22 15:44:38]

this makes me sad. can something be done about this?

[Jim Stichnoth, 2015/12/28 07:54:07]

What is your specific suggestion?  (just to avoid multiple round trips)

Are you thinking that these "target triples" should be tabularized?  to avoid
all the conditionals sprinkled around the various scripts?

+                   'x86-32-nonsfi' if args.nonsfi else 'x86-32-linux',
         }[args.target]
 
         # Only run pnacl-translate in hybrid mode.
@@ -206,7 +210,7 @@ def ProcessPexe(args, pexe, exe):
                  args.llc_args +
                  [pexe],
                  echo=args.verbose)
-        if not args.sandbox:
+        if not sb_or_nonsfi:
             shellcmd((
                 '{objcopy} --redefine-sym _start=_user_start {obj}'
                 ).format(objcopy=objcopy, obj=obj_llc), echo=args.verbose)
@@ -230,6 +234,7 @@ def ProcessPexe(args, pexe, exe):
                        '-ffunction-sections',
                        '-fdata-sections'] if hybrid else []) +
                      (['-sandbox'] if args.sandbox else []) +
+                     (['-nonsfi'] if args.nonsfi else []) +
                      (['-enable-block-profile'] if
                           args.enable_block_profile and not args.sandbox
                           else []) +
@@ -247,7 +252,7 @@ def ProcessPexe(args, pexe, exe):
                 ).format(base=path_addition, asm=asm_sz, obj=obj_sz,
                          triple=triple),
                      echo=args.verbose)
-        if not args.sandbox:
+        if not sb_or_nonsfi:
             shellcmd((
                 '{objcopy} --redefine-sym _start=_user_start {obj}'
                 ).format(objcopy=objcopy, obj=obj_sz), echo=args.verbose)
@@ -313,7 +318,7 @@ def ProcessPexe(args, pexe, exe):
             '{objcopy} --globalize-symbol={start} ' +
             '--globalize-symbol=__Sz_block_profile_info {partial}'
             ).format(objcopy=objcopy, partial=obj_partial,
-                     start='_start' if args.sandbox else '_user_start'),
+                     start='_start' if sb_or_nonsfi else '_user_start'),
                  echo=args.verbose)
 
     # Run the linker regardless of hybrid mode.
@@ -341,6 +346,32 @@ def ProcessPexe(args, pexe, exe):
             ).format(gold=gold, linklib=linklib, partial=obj_partial, exe=exe,
                      root=nacl_root, target=args.target),
                  echo=args.verbose)
+    elif args.nonsfi:
+        # TODO(stichnot): args.nonsfi and args.sandbox branches are nearly
+        # identical; refactor.
+        target_lib_dir = {
+          'arm32': 'arm-nonsfi',
+          'x8632': 'x86-32-nonsfi',
+        }[args.target]
+        linklib = ('{root}/toolchain/linux_x86/pnacl_newlib_raw/translator/' +
+                   '{target_dir}/lib').format(root=nacl_root,
+                                              target_dir=target_lib_dir)
+        shellcmd((
+            '{gold} -nostdlib --no-fix-cortex-a8 --eh-frame-hdr -z text ' +
+            '-z noexecstack ' +
+            '--build-id --entry=__pnacl_start -pie ' +
+            '{linklib}/crtbegin.o {partial} ' +
+            '{root}/toolchain_build/src/subzero/build/runtime/' +
+            'szrt_nonsfi_{target}.o ' +
+            '{linklib}/libpnacl_irt_shim_dummy.a --start-group ' +
+            '{linklib}/libgcc.a {linklib}/libcrt_platform.a ' +
+            '--end-group {linklib}/crtend.o --undefined=_start ' +
+            '--defsym=__Sz_AbsoluteZero=0 ' +
+            '--defsym=_begin=0 ' +
+            '-o {exe}'
+            ).format(gold=gold, linklib=linklib, partial=obj_partial, exe=exe,
+                     root=nacl_root, target=args.target),
+                 echo=args.verbose)
     else:
         linker = {
           'arm32': '/usr/bin/arm-linux-gnueabihf-g++',