[PATCH] D47697: [llvm-mca] Make sure not to end the test files with an empty line.

[Greg Bedwell via Phabricator via llvm-commits]

gbedwell added a comment.

Thanks for the patch!  Annoying that my git client never complained about this one to me.



================
Comment at: utils/update_mca_test_checks.py:445
+  # The file should not end with two newlines. It creates unnecessary churn.
+  while len(output_lines) > 0 and output_lines[-1] == '':
+    output_lines.pop()
----------------
can be simplified to 
```while output_lines and output_lines[-1] == '':```
I think.


================
Comment at: utils/update_mca_test_checks.py:458
   with open(test_path, 'wb') as f:
-    for line in output_lines:
-      f.write('{}\n'.format(line.rstrip()).encode())
-
+    f.writelines([l + '\n' for l in output_lines])
 
----------------
I've been trying to keep this file compatible with Python 2 and 3, ready for inevitably switching the default at some point hence jumping through a few weird hoops with this sort of stuff.  Python 3 now produces:

```
e:\work\upstream-llvm\llvm\utils>py -3 update_mca_test_checks.py ..\test\tools\llvm-mca\*\*.s
Test: ..\test\tools\llvm-mca\ARM\simple-test-cortex-a9.s
      [38 lines total]
Traceback (most recent call last):
  File "update_mca_test_checks.py", line 499, in <module>
    sys.exit(main())
  File "update_mca_test_checks.py", line 491, in main
    prefix_pad)
  File "update_mca_test_checks.py", line 458, in _write_output
    f.writelines([l + '\n' for l in output_lines])
TypeError: a bytes-like object is required, not 'str'
```


Repository:
  rL LLVM

https://reviews.llvm.org/D47697