PNaCl Dynamic Linking: Added portable dependencies to shared objects.

tests/pnacl_dynamic_loading/nacl.scons

 # -*- python -*-
 # Copyright (c) 2014 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 Import('env')
 
 if not env.Bit('bitcode'):
   Return()
 # Translating the PSO to an ELF DSO doesn't work on x86-64 yet.  The
 # Gold linker complains that the input "requires dynamic R_X86_64_32
 # reloc against <blah> which may overflow at runtime".  (In contrast,
 # the BFD linker in the glibc toolchain does handle this relocation.)
 # TODO(mseaborn): Fix this and enable the test for x86-64.
 if env.Bit('build_x86_64'):
   Return()
 # TODO(sbc): Enable this test for mips.
 if env.Bit('build_mips32'):
   Return()
 # The sandboxed translator does not support translating PSOs yet.
 if env.Bit('use_sandboxed_translator'):
   Return()
 
+def FinalizePso(dest, opt_result):
+  # Finalize to strip debugging info and to emit PNaCl bitcode.
+  return env.Command(dest + '.so', [opt_result],
+                     '${PNACLFINALIZE} ${SOURCES} -o ${TARGET}')
 

[Mark Seaborn, 2016/03/30 23:24:57]

Style nit: In Python it's preferred to have 2 empty lines between top-level
function decls, so can you preserve that when the code has it already?

[Sean Klein, 2016/04/01 23:12:25]

Done.

-def FinalizeAndTranslatePso(dest, opt_result):
-  # Finalize to strip debugging info and to emit PNaCl bitcode.
-  finalized_result = env.Command(
-      dest + '.final.pso', [opt_result],
-      '${PNACLFINALIZE} ${SOURCES} -o ${TARGET}')
+def TranslatePso(dest, finalized_result):
   # Translate to an ELF loadable object.
-  return env.Command(dest + '.so', [finalized_result],
+  return env.Command(dest + '.so.translated', [finalized_result],
                      '${TRANSLATE} -pso ${SOURCES} -o ${TARGET}')
 
 
 def MakeAndTranslatePso(dest, bitcode_file, llvm_passes):
   # Run opt to optionally apply PNaCl ABI simplifications to the IR and to
   # run the PNaCl ABI checker.  We are bypassing pnacl-ld for now because
   # its invocation of Gold internalizes __pnacl_pso_root, which we want to
   # keep externally-visible.
   opt_result = env.Command(
       dest + '.nonfinal.pso', [bitcode_file],
       '${PNACLOPT} ' + llvm_passes + ' '
       '-verify-pnaclabi-module -verify-pnaclabi-functions '
       '-pnaclabi-allow-debug-metadata '
       '${SOURCES} -o ${TARGET}')
-  return FinalizeAndTranslatePso(dest, opt_result)
+  finalized_result = FinalizePso(dest, opt_result)
+  return TranslatePso(dest, finalized_result)
 
 def PsoFromLLVMAssembly(base_name):
   bitcode_file = env.Command(
       '%s.bc' % base_name, ['%s.ll' % base_name],
       [Action('${ASCOM}', '${ASCOMSTR}')])
   return MakeAndTranslatePso(base_name, [bitcode_file],
                              # Skip PNaCl passes because they add TLS functions.
                              llvm_passes='')
 
 
-def MakeAndTranslatePll(dest, source_file):
+def MakePll(dest, source_file, dependencies):
+  deps = ''
+  if dependencies != []:

[Mark Seaborn, 2016/03/30 23:24:57]

"len(dependencies) != 0" is arguably more idiomatic in Python since it works for
any iterable type.

Or you could make this unconditional.

[Sean Klein, 2016/04/01 23:12:25]

Using "len(dependencies) != 0"

+    deps += ' -L' + Dir('.').abspath
+  for d in dependencies:
+    deps += ' -l:' + d[0].name
   nonfinal_pll = env.Command(
       dest + '.nonfinal.pll', [source_file],
-      '${CC} -shared ${SOURCES} -o ${TARGET}')
-  return FinalizeAndTranslatePso(dest, nonfinal_pll)
+      '${CC} -shared ${SOURCES} -o ${TARGET}' + deps)
+  for d in dependencies:

[Mark Seaborn, 2016/03/30 23:24:57]

I think you can do
Depends(nonfinal_pll, dependencies)
for brevity

[Sean Klein, 2016/04/01 23:12:25]

Done.

+    # Linking the nonfinal_pll depends on the untranslated, finalized PLL (.so)
+    # dependencies existing.
+    Depends(nonfinal_pll, d)
+  return FinalizePso(dest, nonfinal_pll)
+
+def MakeAndTranslatePll(dest, source_file, dependencies):
+  finalized_pll = MakePll(dest, source_file, dependencies)
+  return TranslatePso(dest, finalized_pll)
 
 # Under SFI NaCl, the loader currently depends on the allocate_code_data()
 # interface provided by the IRT.
 is_broken = not env.Bit('tests_use_irt') and not env.Bit('nonsfi_nacl')
 
 dso1 = MakeAndTranslatePso(
     'test_pso', [env.ComponentObject('test_pso.c')],
     llvm_passes='-pnacl-abi-simplify-preopt -pnacl-abi-simplify-postopt')
 dso2 = PsoFromLLVMAssembly('data_only_pso')
 dso3 = PsoFromLLVMAssembly('data_only_pso_largebss')
@@ skipping 10 matching lines @@
     node, ['small_tests', 'toolchain_tests'],
     'run_pnacl_dynamic_loading_test', is_broken=is_broken)
 
 
 # Use of the ConvertToPSO pass requires this toolchain version.
 if env['TOOLCHAIN_FEATURE_VERSION'] < 24:
   Return()
 
 # TODO(smklein): These LLVM passes should be automatically applied by the
 # drivers. Once support for dependencies has been plumbed through the drivers,
 # use the "-l" linker flags and don't explicitly declare any LLVM passes.

[Mark Seaborn, 2016/03/30 23:24:57]

Since you're adding "-l" in this change, you could address this TODO.

[Sean Klein, 2016/04/01 23:12:25]

Done. Using "test_pll_a" and "test_pll_b", since MakeAndTranslatePll likes to
operate on real scons nodes.

 test_pll = MakeAndTranslatePso(
     'test_pll', [env.ComponentObject('test_pll.c')],
     llvm_passes='-nacl-global-cleanup -expand-varargs '
     '-rewrite-pnacl-library-calls -rewrite-llvm-intrinsic-calls '
     '-convert-to-pso -convert-to-pso-deps=libfoo.so,libbar.so '
     '-pnacl-abi-simplify-postopt')
-
-test_pll_tls = MakeAndTranslatePll('test_pll_tls', 'test_pll_tls.c')
+test_pll_tls = MakeAndTranslatePll('test_pll_tls', 'test_pll_tls.c', [])
 
 pll_symbols_test = env.ComponentProgram(
     'pll_symbols_test', ['pll_symbols_test.cc'],
     EXTRA_LIBS=['${NONIRT_LIBS}', 'pnacl_dynloader', 'pll_loader_lib'])
 
 node = env.CommandSelLdrTestNacl(
     'pll_symbols_test.out', pll_symbols_test, [test_pll, test_pll_tls],
     # Add '-a' to enable filesystem access for opening DSOs.
     sel_ldr_flags=['-a'])
 env.AddNodeToTestSuite(
     node, ['small_tests', 'toolchain_tests'],
     'run_pll_symbols_test', is_broken=is_broken)
 
 
-test_pll_a = MakeAndTranslatePll('test_pll_a', 'test_pll_a.c')
-test_pll_b = MakeAndTranslatePll('test_pll_b', 'test_pll_b.c')
+test_pll_a_finalized = MakePll('test_pll_a', 'test_pll_a.c', [])
+test_pll_a = TranslatePso('test_pll_a', test_pll_a_finalized)
+test_pll_b_finalized = MakePll('test_pll_b', 'test_pll_b.c',
+                               [test_pll_a_finalized])
+test_pll_b = TranslatePso('test_pll_b', test_pll_b_finalized)
 
 pll_loader_test = env.ComponentProgram(
     'pll_loader_test', ['pll_loader_test.cc'],
     EXTRA_LIBS=['${NONIRT_LIBS}', 'pll_loader_lib'])
 
 node = env.CommandSelLdrTestNacl(
     'pll_loader_test.out', pll_loader_test,
     [Dir('.').abspath, 'test_pll_a.so', 'test_pll_b.so', 'test_pll_tls.so'],
     # Add '-a' to enable filesystem access for opening DSOs.
     sel_ldr_flags=['-a'],
     extra_deps=[test_pll_a, test_pll_b, test_pll_tls])
 env.AddNodeToTestSuite(
     node, ['small_tests', 'toolchain_tests'],
     'run_pll_loader_test', is_broken=is_broken)
 
 
-pll_libc = env.Command(
+pll_libc_nonfinal = env.Command(
     'libc${OBJSUFFIX}',
     # libnacl should come first so that it can override definitions in libc.
     [env.File('${LIB_DIR}/libnacl.a'),
      env.File('${NACL_SDK_LIB}/libc.a'),
      env.ComponentObject('libc_entry.c')],
     '${CC} -shared -Wl,--whole-archive ${SOURCES} -o ${TARGET}')
 
-translated_pll_libc = FinalizeAndTranslatePso('translated_pll_libc', pll_libc)
-translated_pll_hello_world = MakeAndTranslatePll(
-    'translated_pll_hello_world',
-    '../hello_world/hello_world.c')
+pll_libc_finalized = FinalizePso('pll_libc', pll_libc_nonfinal)
+pll_libc = TranslatePso('pll_libc', pll_libc_finalized)
+
+pll_hello_world = MakeAndTranslatePll(
+    'pll_hello_world',
+    '../hello_world/hello_world.c',
+    [pll_libc_finalized])
 
 # Ideally we would have this ComponentProgram() definition in
 # src/untrusted/pll_loader/nacl.scons instead; see the comment there for
 # why we don't.
 pll_loader = env.ComponentProgram(
     'pll_loader', [],
     EXTRA_LIBS=['${NONIRT_LIBS}', 'pll_loader_main', 'pll_loader_lib'])
 
 node = env.CommandSelLdrTestNacl(
     'pll_hello_world_test.out', pll_loader,
-    [translated_pll_libc, translated_pll_hello_world],
+    [Dir('.').abspath, 'pll_hello_world.so'],
     # Add '-a' to enable filesystem access for opening DSOs.
     sel_ldr_flags=['-a'],
-    stdout_golden=env.File('../hello_world/hello_world.stdout'))
+    stdout_golden=env.File('../hello_world/hello_world.stdout'),
+    extra_deps=[pll_libc, pll_hello_world])
 env.AddNodeToTestSuite(
     node, ['small_tests', 'toolchain_tests'],
     'run_pll_hello_world_test', is_broken=is_broken)
+
+
+test_pll_c_finalized = MakePll(
+    'test_pll_c', 'test_pll_c.c', [test_pll_a_finalized, test_pll_b_finalized])
+test_pll_c = TranslatePso('test_pll_c', test_pll_c_finalized)
+
+pll_dependencies_test = MakeAndTranslatePll(
+    'pll_dependencies_test', 'dependencies_test.c',
+    [pll_libc_finalized, test_pll_c_finalized])
+
+node = env.CommandSelLdrTestNacl(
+    'pll_dependencies_test.out', pll_loader,
+    [Dir('.').abspath, 'pll_dependencies_test.so'],
+    # Add '-a' to enable filesystem access for opening DSOs.
+    sel_ldr_flags=['-a'], stdout_golden=env.File('dependencies_test.stdout'),
+    extra_deps=[pll_libc, test_pll_a, test_pll_b, test_pll_c,
+    pll_dependencies_test])

[Mark Seaborn, 2016/03/30 23:24:57]

Nit: indent to align with "["

[Sean Klein, 2016/04/01 23:12:25]

Done.

+env.AddNodeToTestSuite(
+    node, ['small_tests', 'toolchain_tests'], 'run_pll_dependencies_test',
+    is_broken=is_broken)