[UpdateTestUtils] Print test filename when complaining about conflicting prefix

Now that FileCheck eagerly complains when prefixes are unused,
the update script does the same, and  is becoming very common
to need to drop some prefixes, yet figuring out the file
it complains about isn't obvious unless it actually tells us.

1 files changed, 3 insertions, 2 deletions

diff --git a/llvm/utils/UpdateTestChecks/common.py b/llvm/utils/UpdateTestChecks/common.py
index 358a06da..80b0c84 100644
--- a/llvm/utils/UpdateTestChecks/common.py
+++ b/llvm/utils/UpdateTestChecks/common.py
@@ -291,11 +291,12 @@ class function_body(object):
     return self.scrub
 
 class FunctionTestBuilder:
-  def __init__(self, run_list, flags, scrubber_args):
+  def __init__(self, run_list, flags, scrubber_args, path):
     self._verbose = flags.verbose
     self._record_args = flags.function_signature
     self._check_attributes = flags.check_attributes
     self._scrubber_args = scrubber_args
+    self._path = path
     # Strip double-quotes if input was read by UTC_ARGS
     self._replace_value_regex = list(map(lambda x: x.strip('"'), flags.replace_value_regex))
     self._func_dict = {}
@@ -309,7 +310,7 @@ class FunctionTestBuilder:
 
   def finish_and_get_func_dict(self):
     for prefix in self._get_failed_prefixes():
-      warn('Prefix %s had conflicting output from different RUN lines for all functions' % (prefix,))
+      warn('Prefix %s had conflicting output from different RUN lines for all functions in test %s' % (prefix,self._path,))
     return self._func_dict
 
   def func_order(self):