Merge pull request #6 from delcypher/fixes

Mostly fixes for "as"

Author: travitch

driver/as

@@ -15,6 +15,7 @@ import sys
 from utils import *
 from subprocess import *
 from popenwrapper import Popen
+import logconfig
 
 
 class BCFilter(ArgumentListFilter):
@@ -31,18 +32,30 @@ argFilter = BCFilter(sys.argv[1:])
 try:
     [infile] = argFilter.inputFiles
 except ValueError:
+    logging.debug('Input file argument not detected, assuming stdin.')
     infile = "-"
 
+# set llvm-as
+llvmAssembler='llvm-as'
+if os.getenv(llvmCompilerPathEnv):
+    llvmAssembler = os.path.join(os.getenv(llvmCompilerPathEnv), llvmAssembler)
+
 # Now compile this llvm assembly file into a bitcode file.  The output
 # filename is the same as the object with a .bc appended
-(dirs, filename) = os.path.split(argFilter.outFileName)
+try:
+    (dirs, filename) = os.path.split(argFilter.outFileName)
+except AttributeError as e:
+    logging.error('Output file argument not found.\nException message: ' + str(e))
+    sys.exit(1)
+
 bcfilename = '.{0}.bc'.format(filename)
 bcPath = os.path.join(dirs, bcfilename)
-fakeAssembler = ['llvm-as', infile, '-o', bcPath]
-asmProc = subprocess.Popen(fakeAssembler)
+fakeAssembler = [llvmAssembler, infile, '-o', bcPath]
+asmProc = Popen(fakeAssembler)
 realRet = asmProc.wait()
 
 if realRet != 0:
+    logging.error('llvm-as failed')
     sys.exit(realRet)
 
 attachBitcodePathToObject(bcPath, argFilter.outFileName)

driver/utils.py

@@ -7,12 +7,27 @@
 import re
 import sys
 import tempfile
-from driver.popenwrapper import Popen
 
 fullSelfPath = os.path.realpath(__file__)
 prefix = os.path.dirname(fullSelfPath)
 driverDir = prefix
 
+# This is a bit hacky.
+# We cannot do
+# from .popenwrapper import Popen
+# OR
+# from driver.popenwrapper import Popen
+# because then 'as' will not succesfully import us (wllvm/wllvm++ can
+# successfully import however).
+#
+# Using
+# from popenwrapper import Popen
+# will allow 'as' to import us but then wllvm/wllvm++ will not be able to.
+#
+# The work around is to put this directory in the search path for modules.
+sys.path.insert(0,driverDir)
+from popenwrapper import Popen
+
 # Environmental variable for path to compiler tools (clang/llvm-link etc..)
 llvmCompilerPathEnv = 'LLVM_COMPILER_PATH'
 
@@ -229,6 +244,7 @@ def attachBitcodePathToObject(bcPath, outFileName):
     # that won't work.
     (root, ext) = os.path.splitext(outFileName)
     if ext not in ('.o', '.lo', '.os'):
+        _logger.warning('Cannot attach bitcode path to "{0}"'.format(outFileName))
         return
 
     # Now just build a temporary text file with the full path to the
@@ -327,6 +343,9 @@ def __init__(self, cmd, isCxx, prefixPath=None):
     def getBitcodeCompiler(self):
         pth = os.getenv('LLVM_DRAGONEGG_PLUGIN')
         cc = self.getCompiler()
+        # We use '-B' to tell gcc where to look for an assembler.
+        # When we build LLVM bitcode we do not want to use the GNU assembler,
+        # instead we want gcc to use our own assembler (see driver/as).
         return cc + ['-B', driverDir, '-fplugin={0}'.format(pth),
                      '-fplugin-arg-dragonegg-emit-ir']