Make utils/UpdateTestChecks/common.py Python 2/3 compatible and fix print statements.

[MaskRay]

Summary

Part of D42712 that fixes --verbose (sys is not imported) of utils/update_{,llc_}test_checks.py

[asb]

Adding @modocache as reviewer, who has been responsible for making the opt-viewer tools Py2+Py3 compatible. The changes look sensible to me, but the vast majority of the Python I've written for a long time has been Py3.

[MaskRay]

sys is missing so without the revision, --verbose will complain the name is undefined

[modocache]

Mostly looks good, but I had one suggestion!

utils/UpdateTestChecks/common.py

41 ↗

(On Diff #131910)

I think you can call decode regardless. For example, the following code works on both Python 2 and 3:

from __future__ import print_function
import subprocess

out = subprocess.check_output(['ls']).decode()
print(out)

Here it is in an online Python 2 and Python 3 interpreter. (I don't think there's much overhead to doing so on Python 2, but if you're worried about that it might be worth looking into.)

[MaskRay]

In D42674#995403, @modocache wrote:

Mostly looks good, but I had one suggestion!

In Python 2, str.decode returns unicode. I just want to ensure everything is str in both Python 2 and Python 3.

[modocache]

Oh I see! Thanks for the tip, I didn't know that.

[modocache]

Oops, sorry, I should have accepted this revision along with my last comment. Thanks for making this change!

llvm/trunk/utils/UpdateTestChecks/common.py

+from __future__ import print_function
 import re
 import subprocess
+import sys
 
 RUN_LINE_RE = re.compile('^\s*;\s*RUN:\s*(.*)$')
 CHECK_PREFIX_RE = re.compile('--?check-prefix(?:es)?=(\S+)')
 CHECK_RE = re.compile(r'^\s*;\s*([^:]+?)(?:-NEXT|-NOT|-DAG|-LABEL)?:')
 
 IR_FUNCTION_RE = re.compile('^\s*define\s+(?:internal\s+)?[^@]*@(\w+)\s*\(')
 TRIPLE_IR_RE = re.compile(r'^target\s+triple\s*=\s*"([^"]+)"$')
 TRIPLE_ARG_RE = re.compile(r'-mtriple=([^ ]+)')
def should_add_line_to_output(input_line, prefix_set):
 
   return True
 
 # Invoke the tool that is being tested.
 def invoke_tool(exe, cmd_args, ir):
   with open(ir) as ir_file:
     stdout = subprocess.check_output(exe + ' ' + cmd_args,
                                      shell=True, stdin=ir_file)
+    if sys.version_info[0] > 2:
+      stdout = stdout.decode()
   # Fix line endings to unix CR style.
-  stdout = stdout.replace('\r\n', '\n')
-  return stdout
+  return stdout.replace('\r\n', '\n')
 
 # Build up a dictionary of all the function bodies.
 def build_function_body_dictionary(function_re, scrubber, scrubber_args, raw_tool_output, prefixes, func_dict, verbose):
   for m in function_re.finditer(raw_tool_output):
     if not m:
       continue
     func = m.group('func')
     scrubbed_body = scrubber(m.group('body'), *scrubber_args)
     if func.startswith('stress'):
       # We only use the last line of the function body for stress tests.
       scrubbed_body = '\n'.join(scrubbed_body.splitlines()[-1:])
     if verbose:
-      print >>sys.stderr, 'Processing function: ' + func
+      print('Processing function: ' + func, file=sys.stderr)
       for l in scrubbed_body.splitlines():
-        print >>sys.stderr, '  ' + l
+        print('  ' + l, file=sys.stderr)
     for prefix in prefixes:
       if func in func_dict[prefix] and func_dict[prefix][func] != scrubbed_body:
         if prefix == prefixes[-1]:
-          print >>sys.stderr, ('WARNING: Found conflicting asm under the '
-                               'same prefix: %r!' % (prefix,))
+          print('WARNING: Found conflicting asm under the '
+                               'same prefix: %r!' % (prefix,), file=sys.stderr)
         else:
           func_dict[prefix][func] = None
           continue
 
       func_dict[prefix][func] = scrubbed_body