Adjust pnacl-translate sbtc flag override mechanism to append.

pnacl/driver/pnacl-translate.py

 #!/usr/bin/python
 # Copyright (c) 2012 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.
 #
 # IMPORTANT NOTE: If you make local mods to this file, you must run:
 #   %  pnacl/build.sh driver
 # in order for them to take effect in the scons build.  This command
 # updates the copy in the toolchain/ tree.
 #
@@ skipping 106 matching lines @@
     ('-arm-reserve-r9 -sfi-disable-cp ' +
      '-sfi-load -sfi-store -sfi-stack -sfi-branch -sfi-data ' +
      '-no-inline-jumptables -float-abi=hard'),
 
   'LLC_FLAGS_X8632' : '',
   'LLC_FLAGS_X8664' : '',
 
   'LLC_FLAGS_MIPS32': '-sfi-load -sfi-store -sfi-stack -sfi-branch -sfi-data',
 
   # LLC flags which set the target and output type.
-  # These are handled separately by libLTO.
-  'LLC_FLAGS_TARGET' : '-mcpu=${LLC_MCPU} ' +
-                       '-mtriple=${TRIPLE} ' +
-                       '-filetype=${filetype}',
+  'LLC_FLAGS_TARGET' : '-mtriple=${TRIPLE} -filetype=${filetype}',
+
   # Append additional non-default flags here.
-  'LLC_FLAGS_EXTRA' : '${#OPT_LEVEL ? -O${OPT_LEVEL}} ' +
+  'LLC_FLAGS_EXTRA' : '${FAST_TRANSLATION ? ${LLC_FLAGS_FAST}} ' +
+                      '${#OPT_LEVEL ? -O${OPT_LEVEL}} ' +
                       '${OPT_LEVEL == 0 ? -disable-fp-elim}',
 
   # Opt level from command line (if any)
   'OPT_LEVEL' : '',
 
-  # slower translation == faster code
-  'LLC_FLAGS_SLOW':
-  # Due to a quadratic algorithm used for tail merging
-  # capping it at 50 helps speed up translation
-                     '-tail-merge-threshold=50',
-
   # faster translation == slower code
   'LLC_FLAGS_FAST' : '${LLC_FLAGS_FAST_%ARCH%}',
 
-  'LLC_FLAGS_FAST_X8632':
-                          '-O0 ' +
-  # This, surprisingly, makes a measurable difference
+  'LLC_FLAGS_FAST_X8632': '-O0 ' +
+                          # This, surprisingly, makes a measurable difference
                           '-tail-merge-threshold=20',
-  'LLC_FLAGS_FAST_X8664':
-                          '-O0 ' +
+  'LLC_FLAGS_FAST_X8664': '-O0 ' +
                           '-tail-merge-threshold=20',
-  'LLC_FLAGS_FAST_ARM':
-  # due to slow turn around times ARM settings have not been explored in depth
-                          '-O0 ' +
+  'LLC_FLAGS_FAST_ARM':   '-O0 ' +
                           '-tail-merge-threshold=20',
   'LLC_FLAGS_FAST_MIPS32': '-fast-isel -tail-merge-threshold=20',
 
-  'LLC_FLAGS': '${LLC_FLAGS_TARGET} ' +
-               '${LLC_FLAGS_COMMON} ' +
-               '${LLC_FLAGS_%ARCH%} ' +
-               '${FAST_TRANSLATION ? ${LLC_FLAGS_FAST} : ${LLC_FLAGS_SLOW}} ' +
+  'LLC_FLAGS': '${LLC_FLAGS_TARGET} ${LLC_FLAGS_COMMON} ${LLC_FLAGS_%ARCH%} ' +
                '${LLC_FLAGS_EXTRA}',
 
   # CPU that is representative of baseline feature requirements for NaCl
   # and/or chrome.  We may want to make this more like "-mtune"
   # by specifying both "-mcpu=X" and "-mattr=+feat1,-feat2,...".
   # Note: this may be different from the in-browser translator, which may
   # do auto feature detection based on CPUID, but constrained by what is
   # accepted by NaCl validators.
-  'LLC_MCPU'        : '${LLC_MCPU_%ARCH%}',
+  'LLC_MCPU'        : '-mcpu=${LLC_MCPU_%ARCH%}',
   'LLC_MCPU_ARM'    : 'cortex-a8',
   'LLC_MCPU_X8632'  : 'pentium4',
   'LLC_MCPU_X8664'  : 'core2',
   'LLC_MCPU_MIPS32' : 'mips32r2',
 
   # Note: this is only used in the unsandboxed case
-  'RUN_LLC'       : '${LLVM_LLC} ${LLC_FLAGS} ${input} -o ${output} ' +
+  'RUN_LLC'       : '${LLVM_LLC} ${LLC_FLAGS} ${LLC_MCPU} '
+                    '${input} -o ${output} ' +
                     '-metadata-text ${output}.meta',
   # Rate in bits/sec to stream the bitcode from sel_universal over SRPC
   # for testing. Defaults to 1Gbps (effectively unlimited).
   'BITCODE_STREAM_RATE' : '1000000000',
 }
 
 TranslatorPatterns = [
   ( '-o(.+)',          "env.set('OUTPUT', pathtools.normalize($0))"),
   ( ('-o', '(.+)'),    "env.set('OUTPUT', pathtools.normalize($0))"),
 
   ( '-S',              "env.set('OUTPUT_TYPE', 's')"), # Stop at .s
   ( '-c',              "env.set('OUTPUT_TYPE', 'o')"), # Stop at .o
 
   # Expose a very limited set of llc flags.
   ( '(-sfi-.+)',        "env.append('LLC_FLAGS_EXTRA', $0)"),
   ( '(-mtls-use-call)', "env.append('LLC_FLAGS_EXTRA', $0)"),
   # These flags are usually used for linktime dead code/data
   # removal but also help with reloc overflows on ARM
   ( '(-fdata-sections)',     "env.append('LLC_FLAGS_EXTRA', $0)"),
   ( '(-ffunction-sections)', "env.append('LLC_FLAGS_EXTRA', $0)"),
   ( '(--gc-sections)',       "env.append('LD_FLAGS', $0)"),
   ( '(-mattr=.*)', "env.append('LLC_FLAGS_EXTRA', $0)"),
-  ( '-mcpu=(.*)', "env.set('LLC_MCPU', $0)"),
+  ( '(-mcpu=.*)', "env.set('LLC_MCPU', '')\n"
+                  "env.append('LLC_FLAGS_EXTRA', $0)"),
   # Allow overriding the -O level.
   ( '-O([0-3])', "env.set('OPT_LEVEL', $0)"),
 
   # This adds arch specific flags to the llc invocation aimed at
   # improving translation speed at the expense of code quality.
   ( '-translate-fast',  "env.set('FAST_TRANSLATION', '1')"),
 
   # If translating a .pexe which was linked statically against
   # glibc, then you must do pnacl-translate -static. This will
   # be removed once GLibC is actually statically linked.
@@ skipping 245 matching lines @@
 
 def ToggleDefaultCommandlineLD(inputs, infile):
   if env.getbool('USE_DEFAULT_CMD_LINE'):
     reason, non_standard = RequiresNonStandardLDCommandline(inputs, infile)
     if non_standard:
       Log.Info(reason + ' -- not using default SRPC commandline for LD!')
       inputs.append('--pnacl-driver-set-USE_DEFAULT_CMD_LINE=0')
 
 
 def RequiresNonStandardLLCCommandline():
-  if env.getbool('FAST_TRANSLATION'):
-    return ('FAST_TRANSLATION', True)
-
   extra_flags = env.get('LLC_FLAGS_EXTRA')
   if extra_flags != []:
     reason = 'Has additional llc flags: %s' % extra_flags
     return (reason, True)
 
   return (None, False)
 
 
 def UseDefaultCommandlineLLC():
   if not env.getbool('USE_DEFAULT_CMD_LINE'):
@@ skipping 35 matching lines @@
     # As a side effect, this creates a temporary file
     if not env.getbool('SAVE_TEMPS'):
       TempFiles.add(outfile + '.meta')
     env.pop()
   return 0
 
 def RunLLCSandboxed():
   driver_tools.CheckTranslatorPrerequisites()
   infile = env.getone('input')
   outfile = env.getone('output')
-  flags = env.get('LLC_FLAGS')
   if not driver_tools.IsBitcode(infile):
     Log.Fatal('Input to sandboxed translator must be bitcode')
-  script = MakeSelUniversalScriptForLLC(infile, outfile, flags)
+  script = MakeSelUniversalScriptForLLC(infile, outfile)
   command = ('${SEL_UNIVERSAL_PREFIX} ${SEL_UNIVERSAL} ${SEL_UNIVERSAL_FLAGS} '
     '-- ${LLC_SB}')
   _, stdout, _  = driver_tools.Run(command,
                                 stdin_contents=script,
                                 # stdout/stderr will be automatically dumped
                                 # upon failure
                                 redirect_stderr=subprocess.PIPE,
                                 redirect_stdout=subprocess.PIPE)
   # Get the values returned from the llc RPC to use in input to ld
   is_shared = re.search(r'output\s+0:\s+i\(([0|1])\)', stdout).group(1)
   is_shared = (is_shared == '1')
   soname = re.search(r'output\s+1:\s+s\("(.*)"\)', stdout).group(1)
   needed_str = re.search(r'output\s+2:\s+s\("(.*)"\)', stdout).group(1)
   # If the delimiter changes, this line needs to change
   needed_libs = [ lib for lib in needed_str.split(r'\n') if lib]
   return is_shared, soname, needed_libs
 
-def BuildLLCCommandLine(flags):
+def BuildOverrideLLCCommandLine():
+  extra_flags = env.get('LLC_FLAGS_EXTRA')
+  # The mcpu is not part of the default flags, so append that too.
+  mcpu = env.getone('LLC_MCPU')
+  if mcpu:
+    extra_flags.append(mcpu)
   # command_line is a NUL (\x00) terminated sequence.
   kTerminator = '\0'
-  command_line = kTerminator.join(['llc'] + flags) + kTerminator
+  command_line = kTerminator.join(extra_flags) + kTerminator
   command_line_escaped = command_line.replace(kTerminator, '\\x00')
   return len(command_line), command_line_escaped
 
-def MakeSelUniversalScriptForLLC(infile, outfile, flags):
+def MakeSelUniversalScriptForLLC(infile, outfile):
   script = []
   script.append('readwrite_file objfile %s' % outfile)
   stream_rate = int(env.getraw('BITCODE_STREAM_RATE'))
   assert stream_rate != 0
   if UseDefaultCommandlineLLC():
     script.append('rpc StreamInit h(objfile) * s()')
   else:
-    cmdline_len, cmdline_escaped = BuildLLCCommandLine(flags)
-    script.append('rpc StreamInitWithCommandLine h(objfile) C(%d,%s) * s()' %
+    cmdline_len, cmdline_escaped = BuildOverrideLLCCommandLine()
+    script.append('rpc StreamInitWithOverrides h(objfile) C(%d,%s) * s()' %
                   (cmdline_len, cmdline_escaped))
   # specify filename, chunk size and rate in bits/s
   script.append('stream_file %s %s %s' % (infile, 64 * 1024, stream_rate))
   script.append('rpc StreamEnd * i() s() s() s()')
   script.append('echo "llc complete"')
   script.append('')
   return '\n'.join(script)
 
 def get_help(argv):
   return """
@@ skipping 16 matching lines @@
 
 ADVANCED OPTIONS:
   -mattr=<+feat1,-feat2>  Toggle specific cpu features on and off.
   -mcpu=<cpu-name>        Target a specific cpu type.  Tunes code as well as
                           turns cpu features on and off.
   -S                      Generate native assembly only.
   -c                      Generate native object file only.
   --pnacl-sb              Use the translator which runs inside the NaCl sandbox.
   -O[0-3]                 Change translation-time optimization level.
 """