Add prototype ccc rewrite.
 - Entry point is tools/ccc/xcc until we are a functional replacement
   for ccc.

This is highly experimental (FIXME/LOC ratio of 3.4%), quite crufty,
and barely usable (and then only on my specific Darwin). However, many
of the right ideas are present, and it already fixes a number of
things gcc gets wrong.

The major missing component is argument translation for tools
(translating driver arguments into cc1/ld/as/etc. arguments). This is
a large part of the driver functionality and will probably double the
LOC, but my hope is that the current architecture is relatively
stable.

Documentation & motivation to follow soon...


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@61739 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/ccc/ccclib/Driver.py b/tools/ccc/ccclib/Driver.py
new file mode 100644
index 0000000..4bf0478
--- /dev/null
+++ b/tools/ccc/ccclib/Driver.py
@@ -0,0 +1,666 @@
+import os
+import sys
+import tempfile
+from pprint import pprint
+
+###
+
+import Arguments
+import Jobs
+import Phases
+import Tools
+import Types
+import Util
+
+# FIXME: Clean up naming of options and arguments. Decide whether to
+# rename Option and be consistent about use of Option/Arg.
+
+####
+
+class MissingArgumentError(ValueError):
+    """MissingArgumentError - An option required an argument but none
+    was given."""
+
+###
+
+class Driver(object):
+    def __init__(self):
+        self.parser = Arguments.createOptionParser()
+
+    def run(self, args):
+        # FIXME: Things to support from environment: GCC_EXEC_PREFIX,
+        # COMPILER_PATH, LIBRARY_PATH, LPATH, CC_PRINT_OPTIONS,
+        # QA_OVERRIDE_GCC3_OPTIONS, ...?
+
+        # FIXME: -V and -b processing
+
+        # Handle some special -ccc- options used for testing which are
+        # only allowed at the beginning of the command line.
+        cccPrintOptions = False
+        cccPrintPhases = False
+        cccUseDriverDriver = True
+        while args and args[0].startswith('-ccc-'):
+            opt,args = args[0][5:],args[1:]
+
+            if opt == 'print-options':
+                cccPrintOptions = True
+            elif opt == 'print-phases':
+                cccPrintPhases = True
+            elif opt == 'no-driver-driver':
+                # FIXME: Remove this once we have some way of being a
+                # cross compiler driver (cross driver compiler? compiler
+                # cross driver? etc.).
+                cccUseDriverDriver = False
+            else:
+                raise ValueError,"Invalid ccc option: %r" % cccPrintOptions
+
+        options = self.parser.chunkArgs(args)
+
+        # FIXME: Ho hum I have just realized -Xarch_ is broken. We really
+        # need to reparse the Arguments after they have been expanded by
+        # -Xarch. How is this going to work?
+        #
+        # Scratch that, we aren't going to do that; it really disrupts the
+        # organization, doesn't consistently work with gcc-dd, and is
+        # confusing. Instead we are going to enforce that -Xarch_ is only
+        # used with options which do not alter the driver behavior. Let's
+        # hope this is ok, because the current architecture is a little
+        # tied to it.
+
+        if cccPrintOptions:
+            self.printOptions(args, options)
+            sys.exit(0)
+
+        self.handleImmediateOptions(args, options)
+
+        if cccUseDriverDriver:
+            phases = self.buildPipeline(options, args)
+        else:
+            phases = self.buildNormalPipeline(options, args)
+
+        if cccPrintPhases:
+            self.printPhases(args, phases)
+            sys.exit(0)
+
+        if 0:
+            print Util.pprint(phases)
+
+        jobs = self.bindPhases(phases, options, args)
+
+        # FIXME: We should provide some basic sanity checking of the
+        # pipeline as a "verification" sort of stage. For example, the
+        # pipeline should never end up writing to an output file in two
+        # places (I think). The pipeline should also never end up writing
+        # to an output file that is an input.
+        #
+        # This is intended to just be a "verify" step, not a functionality
+        # step. It should catch things like the driver driver not
+        # preventing -save-temps, but it shouldn't change behavior (so we
+        # can turn it off in Release-Asserts builds).
+
+        # Print in -### syntax.
+        hasHashHashHash = None
+        for oi in options:
+            if oi.opt and oi.opt.name == '-###':
+                hasHashHashHash = oi
+
+        if hasHashHashHash:
+            self.claim(hasHashHashHash)
+            for j in jobs.iterjobs():
+                if isinstance(j, Jobs.Command):
+                    print '"%s"' % '" "'.join(j.render(args))
+                elif isinstance(j, Jobs.PipedJob):
+                    for c in j.commands:
+                        print '"%s" %c' % ('" "'.join(c.render(args)),
+                                           "| "[c is j.commands[-1]])
+                elif not isinstance(j, JobList):
+                    raise ValueError,'Encountered unknown job.'
+            sys.exit(0)
+
+        for j in jobs.iterjobs():
+            if isinstance(j, Jobs.Command):
+                cmd_args = j.render(args)
+                res = os.spawnvp(os.P_WAIT, cmd_args[0], cmd_args)
+                if res:
+                    sys.exit(res)
+            elif isinstance(j, Jobs.PipedJob):
+                raise NotImplementedError,"Piped jobs aren't implemented yet."
+            else:
+                raise ValueError,'Encountered unknown job.'
+
+    def claim(self, option):
+        # FIXME: Move to OptionList once introduced and implement.
+        pass
+
+    def warning(self, message):
+        print >>sys.stderr,'%s: %s' % (sys.argv[0], message)
+
+    def printOptions(self, args, options):
+        for i,oi in enumerate(options):
+            if isinstance(oi, Arguments.InputArg):
+                name = "<input>"
+            elif isinstance(oi, Arguments.UnknownArg):
+                name = "<unknown>"
+            else:
+                assert oi.opt
+                name = oi.opt.name
+            if isinstance(oi, Arguments.MultipleValuesArg):
+                values = list(oi.getValues(args))
+            elif isinstance(oi, Arguments.ValueArg):
+                values = [oi.getValue(args)]
+            elif isinstance(oi, Arguments.JoinedAndSeparateValuesArg):
+                values = [oi.getJoinedValue(args), oi.getSeparateValue(args)]
+            else:
+                values = []
+            print 'Option %d - Name: "%s", Values: {%s}' % (i, name, 
+                                                            ', '.join(['"%s"' % v 
+                                                                       for v in values]))
+
+    def printPhases(self, args, phases):
+        def printPhase(p, f, steps, arch=None):
+            if p in steps:
+                return steps[p]
+            elif isinstance(p, Phases.BindArchAction):
+                for kid in p.inputs:
+                    printPhase(kid, f, steps, p.arch)
+                steps[p] = len(steps)
+                return
+
+            if isinstance(p, Phases.InputAction):
+                phaseName = 'input'
+                inputStr = '"%s"' % p.filename.getValue(args)
+            else:
+                phaseName = p.phase.name
+                inputs = [printPhase(i, f, steps, arch) 
+                          for i in p.inputs]
+                inputStr = '{%s}' % ', '.join(map(str, inputs))
+            if arch is not None:
+                phaseName += '-' + arch.getValue(args)
+            steps[p] = index = len(steps)
+            print "%d: %s, %s, %s" % (index,phaseName,inputStr,p.type.name)
+            return index
+        steps = {}
+        for phase in phases:
+            printPhase(phase, sys.stdout, steps)
+
+    def handleImmediateOptions(self, args, options):
+        # FIXME: Some driver Arguments are consumed right off the bat,
+        # like -dumpversion. Currently the gcc-dd handles these
+        # poorly, so we should be ok handling them upfront instead of
+        # after driver-driver level dispatching.
+        #
+        # FIXME: The actual order of these options in gcc is all over the
+        # place. The -dump ones seem to be first and in specification
+        # order, but there are other levels of precedence. For example,
+        # -print-search-dirs is evaluated before -print-prog-name=,
+        # regardless of order (and the last instance of -print-prog-name=
+        # wins verse itself).
+        #
+        # FIXME: Do we want to report "argument unused" type errors in the
+        # presence of things like -dumpmachine and -print-search-dirs?
+        # Probably not.
+        for oi in options:
+            if oi.opt is not None:
+                if oi.opt.name == '-dumpmachine':
+                    print 'FIXME: %s' % oi.opt.name
+                    sys.exit(1)
+                elif oi.opt.name == '-dumpspecs':
+                    print 'FIXME: %s' % oi.opt.name
+                    sys.exit(1)
+                elif oi.opt.name == '-dumpversion':
+                    print 'FIXME: %s' % oi.opt.name
+                    sys.exit(1)
+                elif oi.opt.name == '-print-file-name=':
+                    print 'FIXME: %s' % oi.opt.name
+                    sys.exit(1)
+                elif oi.opt.name == '-print-multi-directory':
+                    print 'FIXME: %s' % oi.opt.name
+                    sys.exit(1)
+                elif oi.opt.name == '-print-multi-lib':
+                    print 'FIXME: %s' % oi.opt.name
+                    sys.exit(1)
+                elif oi.opt.name == '-print-prog-name=':
+                    print 'FIXME: %s' % oi.opt.name
+                    sys.exit(1)
+                elif oi.opt.name == '-print-libgcc-file-name':
+                    print 'FIXME: %s' % oi.opt.name
+                    sys.exit(1)
+                elif oi.opt.name == '-print-search-dirs':
+                    print 'FIXME: %s' % oi.opt.name
+                    sys.exit(1)
+
+    def buildNormalPipeline(self, args, inputArgs):
+        hasCombine = None
+        hasSyntaxOnly = None
+        hasDashC = hasDashE = hasDashS = None
+
+        inputType = None
+        inputTypeOpt = None
+        inputs = []
+        for a in args:
+            if isinstance(a, Arguments.InputArg):
+                if inputType is None:
+                    base,ext = os.path.splitext(a.getValue(inputArgs))
+                    if ext and ext in Types.kTypeSuffixMap:
+                        klass = Types.kTypeSuffixMap[ext]
+                    else:
+                        # FIXME: Its not clear why we shouldn't just
+                        # revert to unknown. I think this is more likely a
+                        # bug / unintended behavior in gcc. Not very
+                        # important though.
+                        klass = Types.ObjectType
+                else:
+                    assert inputTypeOpt is not None
+                    self.claim(inputTypeOpt)
+                    klass = inputType
+                inputs.append((klass, a))
+            elif a.opt is not None:
+                # FIXME: We should warn about inconsistent and duplicate
+                # usage of these flags.
+                if a.opt.name == '-E':
+                    hasDashE = a
+                elif a.opt.name == '-S':
+                    hasDashS = a
+                elif a.opt.name == '-c':
+                    hasDashC = a
+                elif a.opt.name == '-fsyntax-only':
+                    hasSyntaxOnly = a
+                elif a.opt.name == '-combine':
+                    hasCombine = a
+                elif a.opt.name == '-filelist':
+                    # FIXME: This might not be good enough. We may
+                    # need to introduce another type of InputArg for
+                    # this case, so that other code which needs to
+                    # know the inputs handles this properly. Best not
+                    # to try and lipo this, for example.
+                    #
+                    # Treat as a linker input.
+                    inputs.append((Types.ObjectType, a))
+                elif a.opt.name == '-x':
+                    self.claim(a)
+                    inputTypeOpt = a
+                    value = a.getValue(inputArgs)
+                    if value in Types.kTypeSpecifierMap:
+                        inputType = Types.kTypeSpecifierMap[value]
+                    else:
+                        # FIXME: How are we going to handle diagnostics.
+                        self.warning("language %s not recognized" % value)
+
+                        # FIXME: Its not clear why we shouldn't just
+                        # revert to unknown. I think this is more likely a
+                        # bug / unintended behavior in gcc. Not very
+                        # important though.
+                        inputType = ObjectType
+
+        # We claim things here so that options for which we silently allow
+        # override only ever claim the used option.
+        if hasCombine:
+            self.claim(hasCombine)
+
+        finalPhase = Phases.Phase.eOrderPostAssemble
+        finalPhaseOpt = None
+
+        # Determine what compilation mode we are in.
+        if hasDashE:
+            finalPhase = Phases.Phase.eOrderPreprocess
+            finalPhaseOpt = hasDashE
+        elif hasSyntaxOnly:
+            finalPhase = Phases.Phase.eOrderCompile
+            finalPhaseOpt = hasSyntaxOnly
+        elif hasDashS:
+            finalPhase = Phases.Phase.eOrderCompile
+            finalPhaseOpt = hasDashS
+        elif hasDashC:
+            finalPhase = Phases.Phase.eOrderAssemble
+            finalPhaseOpt = hasDashC    
+
+        if finalPhaseOpt:
+            self.claim(finalPhaseOpt)
+
+        # FIXME: Support -combine.
+        if hasCombine:
+            raise NotImplementedError,"-combine is not yet supported."
+
+        actions = []
+        linkerInputs = []
+        # FIXME: This is gross.
+        linkPhase = Phases.LinkPhase()
+        for klass,input in inputs:
+            # Figure out what step to start at.
+
+            # FIXME: This should be part of the input class probably?
+            # Altough it doesn't quite fit there either, things like
+            # asm-with-preprocess don't easily fit into a linear scheme.
+
+            # FIXME: I think we are going to end up wanting to just build
+            # a simple FSA which we run the inputs down.
+            sequence = []
+            if klass.preprocess:
+                sequence.append(Phases.PreprocessPhase())
+            if klass == Types.ObjectType:
+                sequence.append(linkPhase)
+            elif klass.onlyAssemble:
+                sequence.extend([Phases.AssemblePhase(),
+                                 linkPhase])
+            elif klass.onlyPrecompile:
+                sequence.append(Phases.PrecompilePhase())
+            else:
+                sequence.extend([Phases.CompilePhase(),
+                                 Phases.AssemblePhase(),
+                                 linkPhase])
+
+            if sequence[0].order > finalPhase:
+                assert finalPhaseOpt and finalPhaseOpt.opt
+                # FIXME: Explain what type of input file is. Or just match
+                # gcc warning.
+                self.warning("%s: %s input file unused when %s is present" % (input.getValue(inputArgs),
+                                                                              sequence[0].name,
+                                                                              finalPhaseOpt.opt.name))
+            else:
+                # Build the pipeline for this file.
+
+                current = Phases.InputAction(input, klass)
+                for transition in sequence:
+                    # If the current action produces no output, or we are
+                    # past what the user requested, we are done.
+                    if (current.type is Types.NothingType or
+                        transition.order > finalPhase):
+                        break
+                    else:
+                        if isinstance(transition, Phases.PreprocessPhase):
+                            assert isinstance(klass.preprocess, Types.InputType)
+                            current = Phases.JobAction(transition,
+                                                       [current],
+                                                       klass.preprocess)
+                        elif isinstance(transition, Phases.PrecompilePhase):
+                            current = Phases.JobAction(transition,
+                                                       [current],
+                                                       Types.PCHType)
+                        elif isinstance(transition, Phases.CompilePhase):
+                            if hasSyntaxOnly:
+                                output = Types.NothingType
+                            else:
+                                output = Types.AsmTypeNoPP
+                            current = Phases.JobAction(transition,
+                                                       [current],
+                                                       output)
+                        elif isinstance(transition, Phases.AssemblePhase):
+                            current = Phases.JobAction(transition,
+                                                       [current],
+                                                       Types.ObjectType)
+                        elif transition is linkPhase:
+                            linkerInputs.append(current)
+                            current = None
+                            break
+                        else:
+                            raise RuntimeError,'Unrecognized transition: %s.' % transition
+                        pass
+
+                if current is not None:
+                    assert not isinstance(current, Phases.InputAction)
+                    actions.append(current)
+
+        if linkerInputs:
+            actions.append(Phases.JobAction(linkPhase,
+                                            linkerInputs, 
+                                            Types.ImageType))
+
+        return actions
+
+    def buildPipeline(self, args, inputArgs):
+        # FIXME: We need to handle canonicalization of the specified arch.
+
+        archs = []
+        hasOutput = None
+        hasDashM = hasSaveTemps = None
+        for o in args:
+            if o.opt is None:
+                continue
+
+            if isinstance(o, Arguments.ValueArg):
+                if o.opt.name == '-arch':
+                    archs.append(o)
+            elif o.opt.name.startswith('-M'):
+                hasDashM = o
+            elif o.opt.name in ('-save-temps','--save-temps'):
+                hasSaveTemps = o
+
+        if not archs:
+            # FIXME: Need to infer arch so that we sub -Xarch
+            # correctly.
+            archs.append(Arguments.DerivedArg('i386'))
+
+        actions = self.buildNormalPipeline(args, inputArgs)
+
+        # FIXME: Use custom exception for this.
+        #
+        # FIXME: We killed off some others but these aren't yet detected in
+        # a functional manner. If we added information to jobs about which
+        # "auxiliary" files they wrote then we could detect the conflict
+        # these cause downstream.
+        if len(archs) > 1:
+            if hasDashM:
+                raise ValueError,"Cannot use -M options with multiple arch flags."
+            elif hasSaveTemps:
+                raise ValueError,"Cannot use -save-temps with multiple arch flags."
+
+        # Execute once per arch.
+        finalActions = []
+        for p in actions:
+            #  Make sure we can lipo this kind of output. If not (and it
+            #  is an actual output) then we disallow, since we can't
+            #  create an output file with the right name without
+            #  overwriting it. We could remove this oddity by just
+            #  changing the output names to include the arch, which would
+            #  also fix -save-temps. Compatibility wins for now.
+            #
+            # FIXME: Is this error substantially less useful than
+            # gcc-dd's? The main problem is that "Cannot use compiler
+            # output with multiple arch flags" won't make sense to most
+            # developers.
+            if (len(archs) > 1 and
+                p.type not in (Types.NothingType,Types.ObjectType,Types.ImageType)):
+                raise ValueError,'Cannot use %s output with multiple arch flags.' % p.type.name
+
+            inputs = []
+            for arch in archs:
+                inputs.append(Phases.BindArchAction(p, arch))
+
+            # Lipo if necessary. We do it this way because we need to set
+            # the arch flag so that -Xarch_ gets rewritten.
+            if len(inputs) == 1 or p.type == Types.NothingType:
+                finalActions.extend(inputs)
+            else:
+                finalActions.append(Phases.JobAction(Phases.LipoPhase(),
+                                                     inputs, 
+                                                     p.type))
+
+        # FIXME: We need to add -Wl,arch_multiple and -Wl,final_output in
+        # certain cases. This may be icky because we need to figure out the
+        # mode first. Current plan is to hack on the pipeline once it is built
+        # and we know what is being spit out. This avoids having to handling
+        # things like -c and -combine in multiple places.
+        #
+        # The annoying one of these is -Wl,final_output because it involves
+        # communication across different phases.
+        #
+        # Hopefully we can do this purely as part of the binding, but
+        # leaving comment here for now until it is clear this works.
+
+        return finalActions
+
+    def bindPhases(self, phases, args, inputArgs):
+        jobs = Jobs.JobList()
+
+        finalOutput = None
+        hasSaveTemps = hasNoIntegratedCPP = hasPipe = None
+        forward = []
+        for a in args:
+            if isinstance(a, Arguments.InputArg):
+                pass
+            elif a.opt is not None:
+                if a.opt.name == '-save-temps':
+                    hasSaveTemps = a
+                elif a.opt.name == '-no-integrated-cpp':
+                    hasNoIntegratedCPP = a
+                elif a.opt.name == '-o':
+                    finalOutput = a
+                elif a.opt.name == '-pipe':
+                    hasPipe = a
+                elif a.opt.name in ('-E', '-S', '-c',
+                                    '-arch', '-fsyntax-only', '-combine', '-x',
+                                    '-###'):
+                    pass
+                else:
+                    forward.append(a)
+            else:
+                forward.append(a)
+
+        # We claim things here so that options for which we silently allow
+        # override only ever claim the used option.
+        if hasPipe:
+            self.claim(hasPipe)
+            # FIXME: Hack, override -pipe till we support it.
+            hasPipe = None
+        # Claim these here. Its not completely accurate but any warnings
+        # about these being unused are likely to be noise anyway.
+        if hasSaveTemps:
+            self.claim(hasSaveTemps)
+        if hasNoIntegratedCPP:
+            self.claim(hasNoIntegratedCPP)
+
+        toolMap = {
+            Phases.PreprocessPhase : Tools.GCC_PreprocessTool(),
+            Phases.CompilePhase : Tools.GCC_CompileTool(),
+            Phases.PrecompilePhase : Tools.GCC_PrecompileTool(),
+            Phases.AssemblePhase : Tools.DarwinAssemblerTool(),
+            Phases.LinkPhase : Tools.Collect2Tool(),
+            Phases.LipoPhase : Tools.LipoTool(),
+            }
+
+        class InputInfo:
+            def __init__(self, source, type, baseInput):
+                self.source = source
+                self.type = type
+                self.baseInput = baseInput
+
+            def __repr__(self):
+                return '%s(%r, %r, %r)' % (self.__class__.__name__,
+                                           self.source, self.type, self.baseInput)
+
+        def createJobs(phase, forwardArgs,
+                       canAcceptPipe=False, atTopLevel=False, arch=None):
+            if isinstance(phase, Phases.InputAction):
+                return InputInfo(phase.filename, phase.type, phase.filename)
+            elif isinstance(phase, Phases.BindArchAction):
+                archName = phase.arch.getValue(inputArgs)
+                filteredArgs = []
+                for oi in forwardArgs:
+                    if oi.opt is None:
+                        filteredArgs.append(oi)
+                    elif oi.opt.name == '-arch':
+                        if oi is phase.arch:
+                            filteredArgs.append(oi)
+                    elif oi.opt.name == '-Xarch_':
+                        # FIXME: gcc-dd has another conditional for passing
+                        # through, when the arch conditional array has an empty
+                        # string. Why?
+                        if oi.getJoinedValue(inputArgs) == archName:
+                            # FIXME: This is wrong, we don't want a
+                            # DerivedArg we want an actual parsed version
+                            # of this arg.
+                            filteredArgs.append(Arguments.DerivedArg(oi.getSeparateValue(inputArgs)))
+                    else:
+                        filteredArgs.append(oi)
+                        
+                return createJobs(phase.inputs[0], filteredArgs,
+                                  canAcceptPipe, atTopLevel, phase.arch)
+
+            assert isinstance(phase, Phases.JobAction)
+            tool = toolMap[phase.phase.__class__]
+
+            # See if we should use an integrated CPP. We only use an
+            # integrated cpp when we have exactly one input, since this is
+            # the only use case we care about.
+            useIntegratedCPP = False
+            inputList = phase.inputs
+            if (not hasNoIntegratedCPP and 
+                not hasSaveTemps and
+                tool.hasIntegratedCPP()):
+                if (len(phase.inputs) == 1 and 
+                    isinstance(phase.inputs[0].phase, Phases.PreprocessPhase)):
+                    useIntegratedCPP = True
+                    inputList = phase.inputs[0].inputs
+
+            # Only try to use pipes when exactly one input.
+            canAcceptPipe = len(inputList) == 1 and tool.acceptsPipedInput()
+            inputs = [createJobs(p, forwardArgs, canAcceptPipe, False, arch) for p in inputList]
+
+            # Determine if we should output to a pipe.
+            canOutputToPipe = canAcceptPipe and tool.canPipeOutput()
+            outputToPipe = False
+            if canOutputToPipe:
+                # Some things default to writing to a pipe if the final
+                # phase and there was no user override.  
+                # 
+                # FIXME: What is the best way to handle this?
+                if (atTopLevel and 
+                    isinstance(phase, Phases.PreprocessPhase) and 
+                    not finalOutput):
+                    outputToPipe = True
+                elif hasPipe:
+                    outputToPipe = True
+
+            # Figure out where to put the job (pipes).
+            jobList = jobs
+            if canAcceptPipe and isinstance(inputs[0].source, Jobs.PipedJob):
+                jobList = inputs[0].source
+
+            # Figure out where to put the output.
+            baseInput = inputs[0].baseInput
+            if phase.type == Types.NothingType:
+                output = None            
+            elif outputToPipe:
+                if isinstance(jobList, Jobs.PipedJob):
+                    output = jobList
+                else:
+                    jobList = output = Jobs.PipedJob([])
+                    jobs.addJob(output)
+            else:
+                # Figure out what the derived output location would be.
+                # 
+                # FIXME: gcc has some special case in here so that it doesn't
+                # create output files if they would conflict with an input.
+                inputName = baseInput.getValue(inputArgs)
+                if phase.type is Types.ImageType:
+                    namedOutput = "a.out"
+                else:
+                    base,_ = os.path.splitext(inputName)
+                    assert phase.type.tempSuffix is not None
+                    namedOutput = base + phase.type.tempSuffix
+
+                # Output to user requested destination?
+                if atTopLevel and finalOutput:
+                    output = finalOutput
+                # Contruct a named destination?
+                elif atTopLevel or hasSaveTemps:
+                    output = Arguments.DerivedArg(namedOutput)
+                else:
+                    # Output to temp file...
+                    fd,filename = tempfile.mkstemp(suffix=phase.type.tempSuffix)
+                    output = Arguments.DerivedArg(filename)
+
+            tool.constructJob(phase, arch, jobList, inputs, output, phase.type, forwardArgs)
+
+            return InputInfo(output, phase.type, baseInput)
+
+        # It is an error to provide a -o option if we are making multiple
+        # output files.
+        if finalOutput and len([a for a in phases if a.type is not Types.NothingType]) > 1:
+            # FIXME: Custom exception.
+            raise ValueError,"Cannot specify -o when generating multiple files."
+
+        for phase in phases:
+            createJobs(phase, forward, canAcceptPipe=True, atTopLevel=True)
+
+        return jobs